Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

80 files changed, 41524 insertions, 0 deletions

diff --git a/arch/x86/kernel/cpu/.gitignore b/arch/x86/kernel/cpu/.gitignore
new file mode 100644
index 0000000000..0bca7ef742
--- /dev/null
+++ b/arch/x86/kernel/cpu/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+capflags.c
diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile
new file mode 100644
index 0000000000..4350f6bfc0
--- /dev/null
+++ b/arch/x86/kernel/cpu/Makefile
@@ -0,0 +1,65 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for x86-compatible CPU details, features and quirks
+#
+
+# Don't trace early stages of a secondary CPU boot
+ifdef CONFIG_FUNCTION_TRACER
+CFLAGS_REMOVE_common.o = -pg
+CFLAGS_REMOVE_perf_event.o = -pg
+endif
+
+# If these files are instrumented, boot hangs during the first second.
+KCOV_INSTRUMENT_common.o := n
+KCOV_INSTRUMENT_perf_event.o := n
+KMSAN_SANITIZE_common.o := n
+
+# As above, instrumenting secondary CPU boot code causes boot hangs.
+KCSAN_SANITIZE_common.o := n
+
+obj-y			:= cacheinfo.o scattered.o topology.o
+obj-y			+= common.o
+obj-y			+= rdrand.o
+obj-y			+= match.o
+obj-y			+= bugs.o
+obj-y			+= aperfmperf.o
+obj-y			+= cpuid-deps.o
+obj-y			+= umwait.o
+
+obj-$(CONFIG_PROC_FS)	+= proc.o
+obj-y += capflags.o powerflags.o
+
+obj-$(CONFIG_IA32_FEAT_CTL) += feat_ctl.o
+ifdef CONFIG_CPU_SUP_INTEL
+obj-y			+= intel.o intel_pconfig.o tsx.o
+obj-$(CONFIG_PM)	+= intel_epb.o
+endif
+obj-$(CONFIG_CPU_SUP_AMD)		+= amd.o
+obj-$(CONFIG_CPU_SUP_HYGON)		+= hygon.o
+obj-$(CONFIG_CPU_SUP_CYRIX_32)		+= cyrix.o
+obj-$(CONFIG_CPU_SUP_CENTAUR)		+= centaur.o
+obj-$(CONFIG_CPU_SUP_TRANSMETA_32)	+= transmeta.o
+obj-$(CONFIG_CPU_SUP_UMC_32)		+= umc.o
+obj-$(CONFIG_CPU_SUP_ZHAOXIN)		+= zhaoxin.o
+obj-$(CONFIG_CPU_SUP_VORTEX_32)		+= vortex.o
+
+obj-$(CONFIG_X86_MCE)			+= mce/
+obj-$(CONFIG_MTRR)			+= mtrr/
+obj-$(CONFIG_MICROCODE)			+= microcode/
+obj-$(CONFIG_X86_CPU_RESCTRL)		+= resctrl/
+obj-$(CONFIG_X86_SGX)			+= sgx/
+
+obj-$(CONFIG_X86_LOCAL_APIC)		+= perfctr-watchdog.o
+
+obj-$(CONFIG_HYPERVISOR_GUEST)		+= vmware.o hypervisor.o mshyperv.o
+obj-$(CONFIG_ACRN_GUEST)		+= acrn.o
+
+quiet_cmd_mkcapflags = MKCAP   $@
+      cmd_mkcapflags = $(CONFIG_SHELL) $(srctree)/$(src)/mkcapflags.sh $@ $^
+
+cpufeature = $(src)/../../include/asm/cpufeatures.h
+vmxfeature = $(src)/../../include/asm/vmxfeatures.h
+
+$(obj)/capflags.c: $(cpufeature) $(vmxfeature) $(src)/mkcapflags.sh FORCE
+	$(call if_changed,mkcapflags)
+targets += capflags.c
diff --git a/arch/x86/kernel/cpu/acrn.c b/arch/x86/kernel/cpu/acrn.c
new file mode 100644
index 0000000000..bfeb18fad6
--- /dev/null
+++ b/arch/x86/kernel/cpu/acrn.c
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ACRN detection support
+ *
+ * Copyright (C) 2019 Intel Corporation. All rights reserved.
+ *
+ * Jason Chen CJ <jason.cj.chen@intel.com>
+ * Zhao Yakui <yakui.zhao@intel.com>
+ *
+ */
+
+#include <linux/interrupt.h>
+
+#include <asm/acrn.h>
+#include <asm/apic.h>
+#include <asm/cpufeatures.h>
+#include <asm/desc.h>
+#include <asm/hypervisor.h>
+#include <asm/idtentry.h>
+#include <asm/irq_regs.h>
+
+static u32 __init acrn_detect(void)
+{
+	return acrn_cpuid_base();
+}
+
+static void __init acrn_init_platform(void)
+{
+	/* Setup the IDT for ACRN hypervisor callback */
+	alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_acrn_hv_callback);
+
+	x86_platform.calibrate_tsc = acrn_get_tsc_khz;
+	x86_platform.calibrate_cpu = acrn_get_tsc_khz;
+}
+
+static bool acrn_x2apic_available(void)
+{
+	return boot_cpu_has(X86_FEATURE_X2APIC);
+}
+
+static void (*acrn_intr_handler)(void);
+
+DEFINE_IDTENTRY_SYSVEC(sysvec_acrn_hv_callback)
+{
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
+	/*
+	 * The hypervisor requires that the APIC EOI should be acked.
+	 * If the APIC EOI is not acked, the APIC ISR bit for the
+	 * HYPERVISOR_CALLBACK_VECTOR will not be cleared and then it
+	 * will block the interrupt whose vector is lower than
+	 * HYPERVISOR_CALLBACK_VECTOR.
+	 */
+	apic_eoi();
+	inc_irq_stat(irq_hv_callback_count);
+
+	if (acrn_intr_handler)
+		acrn_intr_handler();
+
+	set_irq_regs(old_regs);
+}
+
+void acrn_setup_intr_handler(void (*handler)(void))
+{
+	acrn_intr_handler = handler;
+}
+EXPORT_SYMBOL_GPL(acrn_setup_intr_handler);
+
+void acrn_remove_intr_handler(void)
+{
+	acrn_intr_handler = NULL;
+}
+EXPORT_SYMBOL_GPL(acrn_remove_intr_handler);
+
+const __initconst struct hypervisor_x86 x86_hyper_acrn = {
+	.name                   = "ACRN",
+	.detect                 = acrn_detect,
+	.type			= X86_HYPER_ACRN,
+	.init.init_platform     = acrn_init_platform,
+	.init.x2apic_available  = acrn_x2apic_available,
+};
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
new file mode 100644
index 0000000000..6e4f23f314
--- /dev/null
+++ b/arch/x86/kernel/cpu/amd.c
@@ -0,0 +1,1333 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/export.h>
+#include <linux/bitops.h>
+#include <linux/elf.h>
+#include <linux/mm.h>
+
+#include <linux/io.h>
+#include <linux/sched.h>
+#include <linux/sched/clock.h>
+#include <linux/random.h>
+#include <linux/topology.h>
+#include <asm/processor.h>
+#include <asm/apic.h>
+#include <asm/cacheinfo.h>
+#include <asm/cpu.h>
+#include <asm/spec-ctrl.h>
+#include <asm/smp.h>
+#include <asm/numa.h>
+#include <asm/pci-direct.h>
+#include <asm/delay.h>
+#include <asm/debugreg.h>
+#include <asm/resctrl.h>
+
+#ifdef CONFIG_X86_64
+# include <asm/mmconfig.h>
+#endif
+
+#include "cpu.h"
+
+/*
+ * nodes_per_socket: Stores the number of nodes per socket.
+ * Refer to Fam15h Models 00-0fh BKDG - CPUID Fn8000_001E_ECX
+ * Node Identifiers[10:8]
+ */
+static u32 nodes_per_socket = 1;
+
+/*
+ * AMD errata checking
+ *
+ * Errata are defined as arrays of ints using the AMD_LEGACY_ERRATUM() or
+ * AMD_OSVW_ERRATUM() macros. The latter is intended for newer errata that
+ * have an OSVW id assigned, which it takes as first argument. Both take a
+ * variable number of family-specific model-stepping ranges created by
+ * AMD_MODEL_RANGE().
+ *
+ * Example:
+ *
+ * const int amd_erratum_319[] =
+ *	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0x4, 0x2),
+ *			   AMD_MODEL_RANGE(0x10, 0x8, 0x0, 0x8, 0x0),
+ *			   AMD_MODEL_RANGE(0x10, 0x9, 0x0, 0x9, 0x0));
+ */
+
+#define AMD_LEGACY_ERRATUM(...)		{ -1, __VA_ARGS__, 0 }
+#define AMD_OSVW_ERRATUM(osvw_id, ...)	{ osvw_id, __VA_ARGS__, 0 }
+#define AMD_MODEL_RANGE(f, m_start, s_start, m_end, s_end) \
+	((f << 24) | (m_start << 16) | (s_start << 12) | (m_end << 4) | (s_end))
+#define AMD_MODEL_RANGE_FAMILY(range)	(((range) >> 24) & 0xff)
+#define AMD_MODEL_RANGE_START(range)	(((range) >> 12) & 0xfff)
+#define AMD_MODEL_RANGE_END(range)	((range) & 0xfff)
+
+static const int amd_erratum_400[] =
+	AMD_OSVW_ERRATUM(1, AMD_MODEL_RANGE(0xf, 0x41, 0x2, 0xff, 0xf),
+			    AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0xff, 0xf));
+
+static const int amd_erratum_383[] =
+	AMD_OSVW_ERRATUM(3, AMD_MODEL_RANGE(0x10, 0, 0, 0xff, 0xf));
+
+/* #1054: Instructions Retired Performance Counter May Be Inaccurate */
+static const int amd_erratum_1054[] =
+	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0, 0, 0x2f, 0xf));
+
+static const int amd_zenbleed[] =
+	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x30, 0x0, 0x4f, 0xf),
+			   AMD_MODEL_RANGE(0x17, 0x60, 0x0, 0x7f, 0xf),
+			   AMD_MODEL_RANGE(0x17, 0x90, 0x0, 0x91, 0xf),
+			   AMD_MODEL_RANGE(0x17, 0xa0, 0x0, 0xaf, 0xf));
+
+static const int amd_div0[] =
+	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x00, 0x0, 0x2f, 0xf),
+			   AMD_MODEL_RANGE(0x17, 0x50, 0x0, 0x5f, 0xf));
+
+static const int amd_erratum_1485[] =
+	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x19, 0x10, 0x0, 0x1f, 0xf),
+			   AMD_MODEL_RANGE(0x19, 0x60, 0x0, 0xaf, 0xf));
+
+static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
+{
+	int osvw_id = *erratum++;
+	u32 range;
+	u32 ms;
+
+	if (osvw_id >= 0 && osvw_id < 65536 &&
+	    cpu_has(cpu, X86_FEATURE_OSVW)) {
+		u64 osvw_len;
+
+		rdmsrl(MSR_AMD64_OSVW_ID_LENGTH, osvw_len);
+		if (osvw_id < osvw_len) {
+			u64 osvw_bits;
+
+			rdmsrl(MSR_AMD64_OSVW_STATUS + (osvw_id >> 6),
+			    osvw_bits);
+			return osvw_bits & (1ULL << (osvw_id & 0x3f));
+		}
+	}
+
+	/* OSVW unavailable or ID unknown, match family-model-stepping range */
+	ms = (cpu->x86_model << 4) | cpu->x86_stepping;
+	while ((range = *erratum++))
+		if ((cpu->x86 == AMD_MODEL_RANGE_FAMILY(range)) &&
+		    (ms >= AMD_MODEL_RANGE_START(range)) &&
+		    (ms <= AMD_MODEL_RANGE_END(range)))
+			return true;
+
+	return false;
+}
+
+static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
+{
+	u32 gprs[8] = { 0 };
+	int err;
+
+	WARN_ONCE((boot_cpu_data.x86 != 0xf),
+		  "%s should only be used on K8!\n", __func__);
+
+	gprs[1] = msr;
+	gprs[7] = 0x9c5a203a;
+
+	err = rdmsr_safe_regs(gprs);
+
+	*p = gprs[0] | ((u64)gprs[2] << 32);
+
+	return err;
+}
+
+static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
+{
+	u32 gprs[8] = { 0 };
+
+	WARN_ONCE((boot_cpu_data.x86 != 0xf),
+		  "%s should only be used on K8!\n", __func__);
+
+	gprs[0] = (u32)val;
+	gprs[1] = msr;
+	gprs[2] = val >> 32;
+	gprs[7] = 0x9c5a203a;
+
+	return wrmsr_safe_regs(gprs);
+}
+
+/*
+ *	B step AMD K6 before B 9730xxxx have hardware bugs that can cause
+ *	misexecution of code under Linux. Owners of such processors should
+ *	contact AMD for precise details and a CPU swap.
+ *
+ *	See	http://www.multimania.com/poulot/k6bug.html
+ *	and	section 2.6.2 of "AMD-K6 Processor Revision Guide - Model 6"
+ *		(Publication # 21266  Issue Date: August 1998)
+ *
+ *	The following test is erm.. interesting. AMD neglected to up
+ *	the chip setting when fixing the bug but they also tweaked some
+ *	performance at the same time..
+ */
+
+#ifdef CONFIG_X86_32
+extern __visible void vide(void);
+__asm__(".text\n"
+	".globl vide\n"
+	".type vide, @function\n"
+	".align 4\n"
+	"vide: ret\n");
+#endif
+
+static void init_amd_k5(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_X86_32
+/*
+ * General Systems BIOSen alias the cpu frequency registers
+ * of the Elan at 0x000df000. Unfortunately, one of the Linux
+ * drivers subsequently pokes it, and changes the CPU speed.
+ * Workaround : Remove the unneeded alias.
+ */
+#define CBAR		(0xfffc) /* Configuration Base Address  (32-bit) */
+#define CBAR_ENB	(0x80000000)
+#define CBAR_KEY	(0X000000CB)
+	if (c->x86_model == 9 || c->x86_model == 10) {
+		if (inl(CBAR) & CBAR_ENB)
+			outl(0 | CBAR_KEY, CBAR);
+	}
+#endif
+}
+
+static void init_amd_k6(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_X86_32
+	u32 l, h;
+	int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);
+
+	if (c->x86_model < 6) {
+		/* Based on AMD doc 20734R - June 2000 */
+		if (c->x86_model == 0) {
+			clear_cpu_cap(c, X86_FEATURE_APIC);
+			set_cpu_cap(c, X86_FEATURE_PGE);
+		}
+		return;
+	}
+
+	if (c->x86_model == 6 && c->x86_stepping == 1) {
+		const int K6_BUG_LOOP = 1000000;
+		int n;
+		void (*f_vide)(void);
+		u64 d, d2;
+
+		pr_info("AMD K6 stepping B detected - ");
+
+		/*
+		 * It looks like AMD fixed the 2.6.2 bug and improved indirect
+		 * calls at the same time.
+		 */
+
+		n = K6_BUG_LOOP;
+		f_vide = vide;
+		OPTIMIZER_HIDE_VAR(f_vide);
+		d = rdtsc();
+		while (n--)
+			f_vide();
+		d2 = rdtsc();
+		d = d2-d;
+
+		if (d > 20*K6_BUG_LOOP)
+			pr_cont("system stability may be impaired when more than 32 MB are used.\n");
+		else
+			pr_cont("probably OK (after B9730xxxx).\n");
+	}
+
+	/* K6 with old style WHCR */
+	if (c->x86_model < 8 ||
+	   (c->x86_model == 8 && c->x86_stepping < 8)) {
+		/* We can only write allocate on the low 508Mb */
+		if (mbytes > 508)
+			mbytes = 508;
+
+		rdmsr(MSR_K6_WHCR, l, h);
+		if ((l&0x0000FFFF) == 0) {
+			unsigned long flags;
+			l = (1<<0)|((mbytes/4)<<1);
+			local_irq_save(flags);
+			wbinvd();
+			wrmsr(MSR_K6_WHCR, l, h);
+			local_irq_restore(flags);
+			pr_info("Enabling old style K6 write allocation for %d Mb\n",
+				mbytes);
+		}
+		return;
+	}
+
+	if ((c->x86_model == 8 && c->x86_stepping > 7) ||
+	     c->x86_model == 9 || c->x86_model == 13) {
+		/* The more serious chips .. */
+
+		if (mbytes > 4092)
+			mbytes = 4092;
+
+		rdmsr(MSR_K6_WHCR, l, h);
+		if ((l&0xFFFF0000) == 0) {
+			unsigned long flags;
+			l = ((mbytes>>2)<<22)|(1<<16);
+			local_irq_save(flags);
+			wbinvd();
+			wrmsr(MSR_K6_WHCR, l, h);
+			local_irq_restore(flags);
+			pr_info("Enabling new style K6 write allocation for %d Mb\n",
+				mbytes);
+		}
+
+		return;
+	}
+
+	if (c->x86_model == 10) {
+		/* AMD Geode LX is model 10 */
+		/* placeholder for any needed mods */
+		return;
+	}
+#endif
+}
+
+static void init_amd_k7(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_X86_32
+	u32 l, h;
+
+	/*
+	 * Bit 15 of Athlon specific MSR 15, needs to be 0
+	 * to enable SSE on Palomino/Morgan/Barton CPU's.
+	 * If the BIOS didn't enable it already, enable it here.
+	 */
+	if (c->x86_model >= 6 && c->x86_model <= 10) {
+		if (!cpu_has(c, X86_FEATURE_XMM)) {
+			pr_info("Enabling disabled K7/SSE Support.\n");
+			msr_clear_bit(MSR_K7_HWCR, 15);
+			set_cpu_cap(c, X86_FEATURE_XMM);
+		}
+	}
+
+	/*
+	 * It's been determined by AMD that Athlons since model 8 stepping 1
+	 * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
+	 * As per AMD technical note 27212 0.2
+	 */
+	if ((c->x86_model == 8 && c->x86_stepping >= 1) || (c->x86_model > 8)) {
+		rdmsr(MSR_K7_CLK_CTL, l, h);
+		if ((l & 0xfff00000) != 0x20000000) {
+			pr_info("CPU: CLK_CTL MSR was %x. Reprogramming to %x\n",
+				l, ((l & 0x000fffff)|0x20000000));
+			wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
+		}
+	}
+
+	/* calling is from identify_secondary_cpu() ? */
+	if (!c->cpu_index)
+		return;
+
+	/*
+	 * Certain Athlons might work (for various values of 'work') in SMP
+	 * but they are not certified as MP capable.
+	 */
+	/* Athlon 660/661 is valid. */
+	if ((c->x86_model == 6) && ((c->x86_stepping == 0) ||
+	    (c->x86_stepping == 1)))
+		return;
+
+	/* Duron 670 is valid */
+	if ((c->x86_model == 7) && (c->x86_stepping == 0))
+		return;
+
+	/*
+	 * Athlon 662, Duron 671, and Athlon >model 7 have capability
+	 * bit. It's worth noting that the A5 stepping (662) of some
+	 * Athlon XP's have the MP bit set.
+	 * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
+	 * more.
+	 */
+	if (((c->x86_model == 6) && (c->x86_stepping >= 2)) ||
+	    ((c->x86_model == 7) && (c->x86_stepping >= 1)) ||
+	     (c->x86_model > 7))
+		if (cpu_has(c, X86_FEATURE_MP))
+			return;
+
+	/* If we get here, not a certified SMP capable AMD system. */
+
+	/*
+	 * Don't taint if we are running SMP kernel on a single non-MP
+	 * approved Athlon
+	 */
+	WARN_ONCE(1, "WARNING: This combination of AMD"
+		" processors is not suitable for SMP.\n");
+	add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
+#endif
+}
+
+#ifdef CONFIG_NUMA
+/*
+ * To workaround broken NUMA config.  Read the comment in
+ * srat_detect_node().
+ */
+static int nearby_node(int apicid)
+{
+	int i, node;
+
+	for (i = apicid - 1; i >= 0; i--) {
+		node = __apicid_to_node[i];
+		if (node != NUMA_NO_NODE && node_online(node))
+			return node;
+	}
+	for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
+		node = __apicid_to_node[i];
+		if (node != NUMA_NO_NODE && node_online(node))
+			return node;
+	}
+	return first_node(node_online_map); /* Shouldn't happen */
+}
+#endif
+
+/*
+ * Fix up cpu_core_id for pre-F17h systems to be in the
+ * [0 .. cores_per_node - 1] range. Not really needed but
+ * kept so as not to break existing setups.
+ */
+static void legacy_fixup_core_id(struct cpuinfo_x86 *c)
+{
+	u32 cus_per_node;
+
+	if (c->x86 >= 0x17)
+		return;
+
+	cus_per_node = c->x86_max_cores / nodes_per_socket;
+	c->cpu_core_id %= cus_per_node;
+}
+
+/*
+ * Fixup core topology information for
+ * (1) AMD multi-node processors
+ *     Assumption: Number of cores in each internal node is the same.
+ * (2) AMD processors supporting compute units
+ */
+static void amd_get_topology(struct cpuinfo_x86 *c)
+{
+	int cpu = smp_processor_id();
+
+	/* get information required for multi-node processors */
+	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
+		int err;
+		u32 eax, ebx, ecx, edx;
+
+		cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
+
+		c->cpu_die_id  = ecx & 0xff;
+
+		if (c->x86 == 0x15)
+			c->cu_id = ebx & 0xff;
+
+		if (c->x86 >= 0x17) {
+			c->cpu_core_id = ebx & 0xff;
+
+			if (smp_num_siblings > 1)
+				c->x86_max_cores /= smp_num_siblings;
+		}
+
+		/*
+		 * In case leaf B is available, use it to derive
+		 * topology information.
+		 */
+		err = detect_extended_topology(c);
+		if (!err)
+			c->x86_coreid_bits = get_count_order(c->x86_max_cores);
+
+		cacheinfo_amd_init_llc_id(c, cpu);
+
+	} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
+		u64 value;
+
+		rdmsrl(MSR_FAM10H_NODE_ID, value);
+		c->cpu_die_id = value & 7;
+
+		per_cpu(cpu_llc_id, cpu) = c->cpu_die_id;
+	} else
+		return;
+
+	if (nodes_per_socket > 1) {
+		set_cpu_cap(c, X86_FEATURE_AMD_DCM);
+		legacy_fixup_core_id(c);
+	}
+}
+
+/*
+ * On a AMD dual core setup the lower bits of the APIC id distinguish the cores.
+ * Assumes number of cores is a power of two.
+ */
+static void amd_detect_cmp(struct cpuinfo_x86 *c)
+{
+	unsigned bits;
+	int cpu = smp_processor_id();
+
+	bits = c->x86_coreid_bits;
+	/* Low order bits define the core id (index of core in socket) */
+	c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
+	/* Convert the initial APIC ID into the socket ID */
+	c->phys_proc_id = c->initial_apicid >> bits;
+	/* use socket ID also for last level cache */
+	per_cpu(cpu_llc_id, cpu) = c->cpu_die_id = c->phys_proc_id;
+}
+
+u32 amd_get_nodes_per_socket(void)
+{
+	return nodes_per_socket;
+}
+EXPORT_SYMBOL_GPL(amd_get_nodes_per_socket);
+
+static void srat_detect_node(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_NUMA
+	int cpu = smp_processor_id();
+	int node;
+	unsigned apicid = c->apicid;
+
+	node = numa_cpu_node(cpu);
+	if (node == NUMA_NO_NODE)
+		node = get_llc_id(cpu);
+
+	/*
+	 * On multi-fabric platform (e.g. Numascale NumaChip) a
+	 * platform-specific handler needs to be called to fixup some
+	 * IDs of the CPU.
+	 */
+	if (x86_cpuinit.fixup_cpu_id)
+		x86_cpuinit.fixup_cpu_id(c, node);
+
+	if (!node_online(node)) {
+		/*
+		 * Two possibilities here:
+		 *
+		 * - The CPU is missing memory and no node was created.  In
+		 *   that case try picking one from a nearby CPU.
+		 *
+		 * - The APIC IDs differ from the HyperTransport node IDs
+		 *   which the K8 northbridge parsing fills in.  Assume
+		 *   they are all increased by a constant offset, but in
+		 *   the same order as the HT nodeids.  If that doesn't
+		 *   result in a usable node fall back to the path for the
+		 *   previous case.
+		 *
+		 * This workaround operates directly on the mapping between
+		 * APIC ID and NUMA node, assuming certain relationship
+		 * between APIC ID, HT node ID and NUMA topology.  As going
+		 * through CPU mapping may alter the outcome, directly
+		 * access __apicid_to_node[].
+		 */
+		int ht_nodeid = c->initial_apicid;
+
+		if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
+			node = __apicid_to_node[ht_nodeid];
+		/* Pick a nearby node */
+		if (!node_online(node))
+			node = nearby_node(apicid);
+	}
+	numa_set_node(cpu, node);
+#endif
+}
+
+static void early_init_amd_mc(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_SMP
+	unsigned bits, ecx;
+
+	/* Multi core CPU? */
+	if (c->extended_cpuid_level < 0x80000008)
+		return;
+
+	ecx = cpuid_ecx(0x80000008);
+
+	c->x86_max_cores = (ecx & 0xff) + 1;
+
+	/* CPU telling us the core id bits shift? */
+	bits = (ecx >> 12) & 0xF;
+
+	/* Otherwise recompute */
+	if (bits == 0) {
+		while ((1 << bits) < c->x86_max_cores)
+			bits++;
+	}
+
+	c->x86_coreid_bits = bits;
+#endif
+}
+
+static void bsp_init_amd(struct cpuinfo_x86 *c)
+{
+	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
+
+		if (c->x86 > 0x10 ||
+		    (c->x86 == 0x10 && c->x86_model >= 0x2)) {
+			u64 val;
+
+			rdmsrl(MSR_K7_HWCR, val);
+			if (!(val & BIT(24)))
+				pr_warn(FW_BUG "TSC doesn't count with P0 frequency!\n");
+		}
+	}
+
+	if (c->x86 == 0x15) {
+		unsigned long upperbit;
+		u32 cpuid, assoc;
+
+		cpuid	 = cpuid_edx(0x80000005);
+		assoc	 = cpuid >> 16 & 0xff;
+		upperbit = ((cpuid >> 24) << 10) / assoc;
+
+		va_align.mask	  = (upperbit - 1) & PAGE_MASK;
+		va_align.flags    = ALIGN_VA_32 | ALIGN_VA_64;
+
+		/* A random value per boot for bit slice [12:upper_bit) */
+		va_align.bits = get_random_u32() & va_align.mask;
+	}
+
+	if (cpu_has(c, X86_FEATURE_MWAITX))
+		use_mwaitx_delay();
+
+	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
+		u32 ecx;
+
+		ecx = cpuid_ecx(0x8000001e);
+		__max_die_per_package = nodes_per_socket = ((ecx >> 8) & 7) + 1;
+	} else if (boot_cpu_has(X86_FEATURE_NODEID_MSR)) {
+		u64 value;
+
+		rdmsrl(MSR_FAM10H_NODE_ID, value);
+		__max_die_per_package = nodes_per_socket = ((value >> 3) & 7) + 1;
+	}
+
+	if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&
+	    !boot_cpu_has(X86_FEATURE_VIRT_SSBD) &&
+	    c->x86 >= 0x15 && c->x86 <= 0x17) {
+		unsigned int bit;
+
+		switch (c->x86) {
+		case 0x15: bit = 54; break;
+		case 0x16: bit = 33; break;
+		case 0x17: bit = 10; break;
+		default: return;
+		}
+		/*
+		 * Try to cache the base value so further operations can
+		 * avoid RMW. If that faults, do not enable SSBD.
+		 */
+		if (!rdmsrl_safe(MSR_AMD64_LS_CFG, &x86_amd_ls_cfg_base)) {
+			setup_force_cpu_cap(X86_FEATURE_LS_CFG_SSBD);
+			setup_force_cpu_cap(X86_FEATURE_SSBD);
+			x86_amd_ls_cfg_ssbd_mask = 1ULL << bit;
+		}
+	}
+
+	resctrl_cpu_detect(c);
+}
+
+static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
+{
+	u64 msr;
+
+	/*
+	 * BIOS support is required for SME and SEV.
+	 *   For SME: If BIOS has enabled SME then adjust x86_phys_bits by
+	 *	      the SME physical address space reduction value.
+	 *	      If BIOS has not enabled SME then don't advertise the
+	 *	      SME feature (set in scattered.c).
+	 *	      If the kernel has not enabled SME via any means then
+	 *	      don't advertise the SME feature.
+	 *   For SEV: If BIOS has not enabled SEV then don't advertise the
+	 *            SEV and SEV_ES feature (set in scattered.c).
+	 *
+	 *   In all cases, since support for SME and SEV requires long mode,
+	 *   don't advertise the feature under CONFIG_X86_32.
+	 */
+	if (cpu_has(c, X86_FEATURE_SME) || cpu_has(c, X86_FEATURE_SEV)) {
+		/* Check if memory encryption is enabled */
+		rdmsrl(MSR_AMD64_SYSCFG, msr);
+		if (!(msr & MSR_AMD64_SYSCFG_MEM_ENCRYPT))
+			goto clear_all;
+
+		/*
+		 * Always adjust physical address bits. Even though this
+		 * will be a value above 32-bits this is still done for
+		 * CONFIG_X86_32 so that accurate values are reported.
+		 */
+		c->x86_phys_bits -= (cpuid_ebx(0x8000001f) >> 6) & 0x3f;
+
+		if (IS_ENABLED(CONFIG_X86_32))
+			goto clear_all;
+
+		if (!sme_me_mask)
+			setup_clear_cpu_cap(X86_FEATURE_SME);
+
+		rdmsrl(MSR_K7_HWCR, msr);
+		if (!(msr & MSR_K7_HWCR_SMMLOCK))
+			goto clear_sev;
+
+		return;
+
+clear_all:
+		setup_clear_cpu_cap(X86_FEATURE_SME);
+clear_sev:
+		setup_clear_cpu_cap(X86_FEATURE_SEV);
+		setup_clear_cpu_cap(X86_FEATURE_SEV_ES);
+	}
+}
+
+static void early_init_amd(struct cpuinfo_x86 *c)
+{
+	u64 value;
+	u32 dummy;
+
+	early_init_amd_mc(c);
+
+	if (c->x86 >= 0xf)
+		set_cpu_cap(c, X86_FEATURE_K8);
+
+	rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
+
+	/*
+	 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
+	 * with P/T states and does not stop in deep C-states
+	 */
+	if (c->x86_power & (1 << 8)) {
+		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
+		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
+	}
+
+	/* Bit 12 of 8000_0007 edx is accumulated power mechanism. */
+	if (c->x86_power & BIT(12))
+		set_cpu_cap(c, X86_FEATURE_ACC_POWER);
+
+	/* Bit 14 indicates the Runtime Average Power Limit interface. */
+	if (c->x86_power & BIT(14))
+		set_cpu_cap(c, X86_FEATURE_RAPL);
+
+#ifdef CONFIG_X86_64
+	set_cpu_cap(c, X86_FEATURE_SYSCALL32);
+#else
+	/*  Set MTRR capability flag if appropriate */
+	if (c->x86 == 5)
+		if (c->x86_model == 13 || c->x86_model == 9 ||
+		    (c->x86_model == 8 && c->x86_stepping >= 8))
+			set_cpu_cap(c, X86_FEATURE_K6_MTRR);
+#endif
+#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
+	/*
+	 * ApicID can always be treated as an 8-bit value for AMD APIC versions
+	 * >= 0x10, but even old K8s came out of reset with version 0x10. So, we
+	 * can safely set X86_FEATURE_EXTD_APICID unconditionally for families
+	 * after 16h.
+	 */
+	if (boot_cpu_has(X86_FEATURE_APIC)) {
+		if (c->x86 > 0x16)
+			set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
+		else if (c->x86 >= 0xf) {
+			/* check CPU config space for extended APIC ID */
+			unsigned int val;
+
+			val = read_pci_config(0, 24, 0, 0x68);
+			if ((val >> 17 & 0x3) == 0x3)
+				set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
+		}
+	}
+#endif
+
+	/*
+	 * This is only needed to tell the kernel whether to use VMCALL
+	 * and VMMCALL.  VMMCALL is never executed except under virt, so
+	 * we can set it unconditionally.
+	 */
+	set_cpu_cap(c, X86_FEATURE_VMMCALL);
+
+	/* F16h erratum 793, CVE-2013-6885 */
+	if (c->x86 == 0x16 && c->x86_model <= 0xf)
+		msr_set_bit(MSR_AMD64_LS_CFG, 15);
+
+	/*
+	 * Check whether the machine is affected by erratum 400. This is
+	 * used to select the proper idle routine and to enable the check
+	 * whether the machine is affected in arch_post_acpi_init(), which
+	 * sets the X86_BUG_AMD_APIC_C1E bug depending on the MSR check.
+	 */
+	if (cpu_has_amd_erratum(c, amd_erratum_400))
+		set_cpu_bug(c, X86_BUG_AMD_E400);
+
+	early_detect_mem_encrypt(c);
+
+	/* Re-enable TopologyExtensions if switched off by BIOS */
+	if (c->x86 == 0x15 &&
+	    (c->x86_model >= 0x10 && c->x86_model <= 0x6f) &&
+	    !cpu_has(c, X86_FEATURE_TOPOEXT)) {
+
+		if (msr_set_bit(0xc0011005, 54) > 0) {
+			rdmsrl(0xc0011005, value);
+			if (value & BIT_64(54)) {
+				set_cpu_cap(c, X86_FEATURE_TOPOEXT);
+				pr_info_once(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n");
+			}
+		}
+	}
+
+	if (cpu_has(c, X86_FEATURE_TOPOEXT))
+		smp_num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1;
+
+	if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && !cpu_has(c, X86_FEATURE_IBPB_BRTYPE)) {
+		if (c->x86 == 0x17 && boot_cpu_has(X86_FEATURE_AMD_IBPB))
+			setup_force_cpu_cap(X86_FEATURE_IBPB_BRTYPE);
+		else if (c->x86 >= 0x19 && !wrmsrl_safe(MSR_IA32_PRED_CMD, PRED_CMD_SBPB)) {
+			setup_force_cpu_cap(X86_FEATURE_IBPB_BRTYPE);
+			setup_force_cpu_cap(X86_FEATURE_SBPB);
+		}
+	}
+}
+
+static void init_amd_k8(struct cpuinfo_x86 *c)
+{
+	u32 level;
+	u64 value;
+
+	/* On C+ stepping K8 rep microcode works well for copy/memset */
+	level = cpuid_eax(1);
+	if ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
+		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
+
+	/*
+	 * Some BIOSes incorrectly force this feature, but only K8 revision D
+	 * (model = 0x14) and later actually support it.
+	 * (AMD Erratum #110, docId: 25759).
+	 */
+	if (c->x86_model < 0x14 && cpu_has(c, X86_FEATURE_LAHF_LM)) {
+		clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
+		if (!rdmsrl_amd_safe(0xc001100d, &value)) {
+			value &= ~BIT_64(32);
+			wrmsrl_amd_safe(0xc001100d, value);
+		}
+	}
+
+	if (!c->x86_model_id[0])
+		strcpy(c->x86_model_id, "Hammer");
+
+#ifdef CONFIG_SMP
+	/*
+	 * Disable TLB flush filter by setting HWCR.FFDIS on K8
+	 * bit 6 of msr C001_0015
+	 *
+	 * Errata 63 for SH-B3 steppings
+	 * Errata 122 for all steppings (F+ have it disabled by default)
+	 */
+	msr_set_bit(MSR_K7_HWCR, 6);
+#endif
+	set_cpu_bug(c, X86_BUG_SWAPGS_FENCE);
+}
+
+static void init_amd_gh(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_MMCONF_FAM10H
+	/* do this for boot cpu */
+	if (c == &boot_cpu_data)
+		check_enable_amd_mmconf_dmi();
+
+	fam10h_check_enable_mmcfg();
+#endif
+
+	/*
+	 * Disable GART TLB Walk Errors on Fam10h. We do this here because this
+	 * is always needed when GART is enabled, even in a kernel which has no
+	 * MCE support built in. BIOS should disable GartTlbWlk Errors already.
+	 * If it doesn't, we do it here as suggested by the BKDG.
+	 *
+	 * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
+	 */
+	msr_set_bit(MSR_AMD64_MCx_MASK(4), 10);
+
+	/*
+	 * On family 10h BIOS may not have properly enabled WC+ support, causing
+	 * it to be converted to CD memtype. This may result in performance
+	 * degradation for certain nested-paging guests. Prevent this conversion
+	 * by clearing bit 24 in MSR_AMD64_BU_CFG2.
+	 *
+	 * NOTE: we want to use the _safe accessors so as not to #GP kvm
+	 * guests on older kvm hosts.
+	 */
+	msr_clear_bit(MSR_AMD64_BU_CFG2, 24);
+
+	if (cpu_has_amd_erratum(c, amd_erratum_383))
+		set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH);
+}
+
+static void init_amd_ln(struct cpuinfo_x86 *c)
+{
+	/*
+	 * Apply erratum 665 fix unconditionally so machines without a BIOS
+	 * fix work.
+	 */
+	msr_set_bit(MSR_AMD64_DE_CFG, 31);
+}
+
+static bool rdrand_force;
+
+static int __init rdrand_cmdline(char *str)
+{
+	if (!str)
+		return -EINVAL;
+
+	if (!strcmp(str, "force"))
+		rdrand_force = true;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+early_param("rdrand", rdrand_cmdline);
+
+static void clear_rdrand_cpuid_bit(struct cpuinfo_x86 *c)
+{
+	/*
+	 * Saving of the MSR used to hide the RDRAND support during
+	 * suspend/resume is done by arch/x86/power/cpu.c, which is
+	 * dependent on CONFIG_PM_SLEEP.
+	 */
+	if (!IS_ENABLED(CONFIG_PM_SLEEP))
+		return;
+
+	/*
+	 * The self-test can clear X86_FEATURE_RDRAND, so check for
+	 * RDRAND support using the CPUID function directly.
+	 */
+	if (!(cpuid_ecx(1) & BIT(30)) || rdrand_force)
+		return;
+
+	msr_clear_bit(MSR_AMD64_CPUID_FN_1, 62);
+
+	/*
+	 * Verify that the CPUID change has occurred in case the kernel is
+	 * running virtualized and the hypervisor doesn't support the MSR.
+	 */
+	if (cpuid_ecx(1) & BIT(30)) {
+		pr_info_once("BIOS may not properly restore RDRAND after suspend, but hypervisor does not support hiding RDRAND via CPUID.\n");
+		return;
+	}
+
+	clear_cpu_cap(c, X86_FEATURE_RDRAND);
+	pr_info_once("BIOS may not properly restore RDRAND after suspend, hiding RDRAND via CPUID. Use rdrand=force to reenable.\n");
+}
+
+static void init_amd_jg(struct cpuinfo_x86 *c)
+{
+	/*
+	 * Some BIOS implementations do not restore proper RDRAND support
+	 * across suspend and resume. Check on whether to hide the RDRAND
+	 * instruction support via CPUID.
+	 */
+	clear_rdrand_cpuid_bit(c);
+}
+
+static void init_amd_bd(struct cpuinfo_x86 *c)
+{
+	u64 value;
+
+	/*
+	 * The way access filter has a performance penalty on some workloads.
+	 * Disable it on the affected CPUs.
+	 */
+	if ((c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
+		if (!rdmsrl_safe(MSR_F15H_IC_CFG, &value) && !(value & 0x1E)) {
+			value |= 0x1E;
+			wrmsrl_safe(MSR_F15H_IC_CFG, value);
+		}
+	}
+
+	/*
+	 * Some BIOS implementations do not restore proper RDRAND support
+	 * across suspend and resume. Check on whether to hide the RDRAND
+	 * instruction support via CPUID.
+	 */
+	clear_rdrand_cpuid_bit(c);
+}
+
+void init_spectral_chicken(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_CPU_UNRET_ENTRY
+	u64 value;
+
+	/*
+	 * On Zen2 we offer this chicken (bit) on the altar of Speculation.
+	 *
+	 * This suppresses speculation from the middle of a basic block, i.e. it
+	 * suppresses non-branch predictions.
+	 *
+	 * We use STIBP as a heuristic to filter out Zen2 from the rest of F17H
+	 */
+	if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && cpu_has(c, X86_FEATURE_AMD_STIBP)) {
+		if (!rdmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, &value)) {
+			value |= MSR_ZEN2_SPECTRAL_CHICKEN_BIT;
+			wrmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, value);
+		}
+	}
+#endif
+	/*
+	 * Work around Erratum 1386.  The XSAVES instruction malfunctions in
+	 * certain circumstances on Zen1/2 uarch, and not all parts have had
+	 * updated microcode at the time of writing (March 2023).
+	 *
+	 * Affected parts all have no supervisor XSAVE states, meaning that
+	 * the XSAVEC instruction (which works fine) is equivalent.
+	 */
+	clear_cpu_cap(c, X86_FEATURE_XSAVES);
+}
+
+static void init_amd_zn(struct cpuinfo_x86 *c)
+{
+	set_cpu_cap(c, X86_FEATURE_ZEN);
+
+#ifdef CONFIG_NUMA
+	node_reclaim_distance = 32;
+#endif
+
+	/* Fix up CPUID bits, but only if not virtualised. */
+	if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
+
+		/* Erratum 1076: CPB feature bit not being set in CPUID. */
+		if (!cpu_has(c, X86_FEATURE_CPB))
+			set_cpu_cap(c, X86_FEATURE_CPB);
+
+		/*
+		 * Zen3 (Fam19 model < 0x10) parts are not susceptible to
+		 * Branch Type Confusion, but predate the allocation of the
+		 * BTC_NO bit.
+		 */
+		if (c->x86 == 0x19 && !cpu_has(c, X86_FEATURE_BTC_NO))
+			set_cpu_cap(c, X86_FEATURE_BTC_NO);
+	}
+}
+
+static bool cpu_has_zenbleed_microcode(void)
+{
+	u32 good_rev = 0;
+
+	switch (boot_cpu_data.x86_model) {
+	case 0x30 ... 0x3f: good_rev = 0x0830107a; break;
+	case 0x60 ... 0x67: good_rev = 0x0860010b; break;
+	case 0x68 ... 0x6f: good_rev = 0x08608105; break;
+	case 0x70 ... 0x7f: good_rev = 0x08701032; break;
+	case 0xa0 ... 0xaf: good_rev = 0x08a00008; break;
+
+	default:
+		return false;
+		break;
+	}
+
+	if (boot_cpu_data.microcode < good_rev)
+		return false;
+
+	return true;
+}
+
+static void zenbleed_check(struct cpuinfo_x86 *c)
+{
+	if (!cpu_has_amd_erratum(c, amd_zenbleed))
+		return;
+
+	if (cpu_has(c, X86_FEATURE_HYPERVISOR))
+		return;
+
+	if (!cpu_has(c, X86_FEATURE_AVX))
+		return;
+
+	if (!cpu_has_zenbleed_microcode()) {
+		pr_notice_once("Zenbleed: please update your microcode for the most optimal fix\n");
+		msr_set_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
+	} else {
+		msr_clear_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
+	}
+}
+
+static void init_amd(struct cpuinfo_x86 *c)
+{
+	early_init_amd(c);
+
+	/*
+	 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
+	 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
+	 */
+	clear_cpu_cap(c, 0*32+31);
+
+	if (c->x86 >= 0x10)
+		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
+
+	/* AMD FSRM also implies FSRS */
+	if (cpu_has(c, X86_FEATURE_FSRM))
+		set_cpu_cap(c, X86_FEATURE_FSRS);
+
+	/* get apicid instead of initial apic id from cpuid */
+	c->apicid = read_apic_id();
+
+	/* K6s reports MCEs but don't actually have all the MSRs */
+	if (c->x86 < 6)
+		clear_cpu_cap(c, X86_FEATURE_MCE);
+
+	switch (c->x86) {
+	case 4:    init_amd_k5(c); break;
+	case 5:    init_amd_k6(c); break;
+	case 6:	   init_amd_k7(c); break;
+	case 0xf:  init_amd_k8(c); break;
+	case 0x10: init_amd_gh(c); break;
+	case 0x12: init_amd_ln(c); break;
+	case 0x15: init_amd_bd(c); break;
+	case 0x16: init_amd_jg(c); break;
+	case 0x17: init_spectral_chicken(c);
+		   fallthrough;
+	case 0x19: init_amd_zn(c); break;
+	}
+
+	/*
+	 * Enable workaround for FXSAVE leak on CPUs
+	 * without a XSaveErPtr feature
+	 */
+	if ((c->x86 >= 6) && (!cpu_has(c, X86_FEATURE_XSAVEERPTR)))
+		set_cpu_bug(c, X86_BUG_FXSAVE_LEAK);
+
+	cpu_detect_cache_sizes(c);
+
+	amd_detect_cmp(c);
+	amd_get_topology(c);
+	srat_detect_node(c);
+
+	init_amd_cacheinfo(c);
+
+	if (!cpu_has(c, X86_FEATURE_LFENCE_RDTSC) && cpu_has(c, X86_FEATURE_XMM2)) {
+		/*
+		 * Use LFENCE for execution serialization.  On families which
+		 * don't have that MSR, LFENCE is already serializing.
+		 * msr_set_bit() uses the safe accessors, too, even if the MSR
+		 * is not present.
+		 */
+		msr_set_bit(MSR_AMD64_DE_CFG,
+			    MSR_AMD64_DE_CFG_LFENCE_SERIALIZE_BIT);
+
+		/* A serializing LFENCE stops RDTSC speculation */
+		set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
+	}
+
+	/*
+	 * Family 0x12 and above processors have APIC timer
+	 * running in deep C states.
+	 */
+	if (c->x86 > 0x11)
+		set_cpu_cap(c, X86_FEATURE_ARAT);
+
+	/* 3DNow or LM implies PREFETCHW */
+	if (!cpu_has(c, X86_FEATURE_3DNOWPREFETCH))
+		if (cpu_has(c, X86_FEATURE_3DNOW) || cpu_has(c, X86_FEATURE_LM))
+			set_cpu_cap(c, X86_FEATURE_3DNOWPREFETCH);
+
+	/* AMD CPUs don't reset SS attributes on SYSRET, Xen does. */
+	if (!cpu_feature_enabled(X86_FEATURE_XENPV))
+		set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
+
+	/*
+	 * Turn on the Instructions Retired free counter on machines not
+	 * susceptible to erratum #1054 "Instructions Retired Performance
+	 * Counter May Be Inaccurate".
+	 */
+	if (cpu_has(c, X86_FEATURE_IRPERF) &&
+	    !cpu_has_amd_erratum(c, amd_erratum_1054))
+		msr_set_bit(MSR_K7_HWCR, MSR_K7_HWCR_IRPERF_EN_BIT);
+
+	check_null_seg_clears_base(c);
+
+	/*
+	 * Make sure EFER[AIBRSE - Automatic IBRS Enable] is set. The APs are brought up
+	 * using the trampoline code and as part of it, MSR_EFER gets prepared there in
+	 * order to be replicated onto them. Regardless, set it here again, if not set,
+	 * to protect against any future refactoring/code reorganization which might
+	 * miss setting this important bit.
+	 */
+	if (spectre_v2_in_eibrs_mode(spectre_v2_enabled) &&
+	    cpu_has(c, X86_FEATURE_AUTOIBRS))
+		WARN_ON_ONCE(msr_set_bit(MSR_EFER, _EFER_AUTOIBRS));
+
+	zenbleed_check(c);
+
+	if (cpu_has_amd_erratum(c, amd_div0)) {
+		pr_notice_once("AMD Zen1 DIV0 bug detected. Disable SMT for full protection.\n");
+		setup_force_cpu_bug(X86_BUG_DIV0);
+	}
+
+	if (!cpu_has(c, X86_FEATURE_HYPERVISOR) &&
+	     cpu_has_amd_erratum(c, amd_erratum_1485))
+		msr_set_bit(MSR_ZEN4_BP_CFG, MSR_ZEN4_BP_CFG_SHARED_BTB_FIX_BIT);
+}
+
+#ifdef CONFIG_X86_32
+static unsigned int amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
+{
+	/* AMD errata T13 (order #21922) */
+	if (c->x86 == 6) {
+		/* Duron Rev A0 */
+		if (c->x86_model == 3 && c->x86_stepping == 0)
+			size = 64;
+		/* Tbird rev A1/A2 */
+		if (c->x86_model == 4 &&
+			(c->x86_stepping == 0 || c->x86_stepping == 1))
+			size = 256;
+	}
+	return size;
+}
+#endif
+
+static void cpu_detect_tlb_amd(struct cpuinfo_x86 *c)
+{
+	u32 ebx, eax, ecx, edx;
+	u16 mask = 0xfff;
+
+	if (c->x86 < 0xf)
+		return;
+
+	if (c->extended_cpuid_level < 0x80000006)
+		return;
+
+	cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
+
+	tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
+	tlb_lli_4k[ENTRIES] = ebx & mask;
+
+	/*
+	 * K8 doesn't have 2M/4M entries in the L2 TLB so read out the L1 TLB
+	 * characteristics from the CPUID function 0x80000005 instead.
+	 */
+	if (c->x86 == 0xf) {
+		cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
+		mask = 0xff;
+	}
+
+	/* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
+	if (!((eax >> 16) & mask))
+		tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff;
+	else
+		tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
+
+	/* a 4M entry uses two 2M entries */
+	tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
+
+	/* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
+	if (!(eax & mask)) {
+		/* Erratum 658 */
+		if (c->x86 == 0x15 && c->x86_model <= 0x1f) {
+			tlb_lli_2m[ENTRIES] = 1024;
+		} else {
+			cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
+			tlb_lli_2m[ENTRIES] = eax & 0xff;
+		}
+	} else
+		tlb_lli_2m[ENTRIES] = eax & mask;
+
+	tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
+}
+
+static const struct cpu_dev amd_cpu_dev = {
+	.c_vendor	= "AMD",
+	.c_ident	= { "AuthenticAMD" },
+#ifdef CONFIG_X86_32
+	.legacy_models = {
+		{ .family = 4, .model_names =
+		  {
+			  [3] = "486 DX/2",
+			  [7] = "486 DX/2-WB",
+			  [8] = "486 DX/4",
+			  [9] = "486 DX/4-WB",
+			  [14] = "Am5x86-WT",
+			  [15] = "Am5x86-WB"
+		  }
+		},
+	},
+	.legacy_cache_size = amd_size_cache,
+#endif
+	.c_early_init   = early_init_amd,
+	.c_detect_tlb	= cpu_detect_tlb_amd,
+	.c_bsp_init	= bsp_init_amd,
+	.c_init		= init_amd,
+	.c_x86_vendor	= X86_VENDOR_AMD,
+};
+
+cpu_dev_register(amd_cpu_dev);
+
+static DEFINE_PER_CPU_READ_MOSTLY(unsigned long[4], amd_dr_addr_mask);
+
+static unsigned int amd_msr_dr_addr_masks[] = {
+	MSR_F16H_DR0_ADDR_MASK,
+	MSR_F16H_DR1_ADDR_MASK,
+	MSR_F16H_DR1_ADDR_MASK + 1,
+	MSR_F16H_DR1_ADDR_MASK + 2
+};
+
+void amd_set_dr_addr_mask(unsigned long mask, unsigned int dr)
+{
+	int cpu = smp_processor_id();
+
+	if (!cpu_feature_enabled(X86_FEATURE_BPEXT))
+		return;
+
+	if (WARN_ON_ONCE(dr >= ARRAY_SIZE(amd_msr_dr_addr_masks)))
+		return;
+
+	if (per_cpu(amd_dr_addr_mask, cpu)[dr] == mask)
+		return;
+
+	wrmsr(amd_msr_dr_addr_masks[dr], mask, 0);
+	per_cpu(amd_dr_addr_mask, cpu)[dr] = mask;
+}
+
+unsigned long amd_get_dr_addr_mask(unsigned int dr)
+{
+	if (!cpu_feature_enabled(X86_FEATURE_BPEXT))
+		return 0;
+
+	if (WARN_ON_ONCE(dr >= ARRAY_SIZE(amd_msr_dr_addr_masks)))
+		return 0;
+
+	return per_cpu(amd_dr_addr_mask[dr], smp_processor_id());
+}
+EXPORT_SYMBOL_GPL(amd_get_dr_addr_mask);
+
+u32 amd_get_highest_perf(void)
+{
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+
+	if (c->x86 == 0x17 && ((c->x86_model >= 0x30 && c->x86_model < 0x40) ||
+			       (c->x86_model >= 0x70 && c->x86_model < 0x80)))
+		return 166;
+
+	if (c->x86 == 0x19 && ((c->x86_model >= 0x20 && c->x86_model < 0x30) ||
+			       (c->x86_model >= 0x40 && c->x86_model < 0x70)))
+		return 166;
+
+	return 255;
+}
+EXPORT_SYMBOL_GPL(amd_get_highest_perf);
+
+static void zenbleed_check_cpu(void *unused)
+{
+	struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
+
+	zenbleed_check(c);
+}
+
+void amd_check_microcode(void)
+{
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
+		return;
+
+	on_each_cpu(zenbleed_check_cpu, NULL, 1);
+}
+
+/*
+ * Issue a DIV 0/1 insn to clear any division data from previous DIV
+ * operations.
+ */
+void noinstr amd_clear_divider(void)
+{
+	asm volatile(ALTERNATIVE("", "div %2\n\t", X86_BUG_DIV0)
+		     :: "a" (0), "d" (0), "r" (1));
+}
+EXPORT_SYMBOL_GPL(amd_clear_divider);
diff --git a/arch/x86/kernel/cpu/aperfmperf.c b/arch/x86/kernel/cpu/aperfmperf.c
new file mode 100644
index 0000000000..fdbb5f0744
--- /dev/null
+++ b/arch/x86/kernel/cpu/aperfmperf.c
@@ -0,0 +1,460 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * x86 APERF/MPERF KHz calculation for
+ * /sys/.../cpufreq/scaling_cur_freq
+ *
+ * Copyright (C) 2017 Intel Corp.
+ * Author: Len Brown <len.brown@intel.com>
+ */
+#include <linux/cpufreq.h>
+#include <linux/delay.h>
+#include <linux/ktime.h>
+#include <linux/math64.h>
+#include <linux/percpu.h>
+#include <linux/rcupdate.h>
+#include <linux/sched/isolation.h>
+#include <linux/sched/topology.h>
+#include <linux/smp.h>
+#include <linux/syscore_ops.h>
+
+#include <asm/cpu.h>
+#include <asm/cpu_device_id.h>
+#include <asm/intel-family.h>
+
+#include "cpu.h"
+
+struct aperfmperf {
+	seqcount_t	seq;
+	unsigned long	last_update;
+	u64		acnt;
+	u64		mcnt;
+	u64		aperf;
+	u64		mperf;
+};
+
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct aperfmperf, cpu_samples) = {
+	.seq = SEQCNT_ZERO(cpu_samples.seq)
+};
+
+static void init_counter_refs(void)
+{
+	u64 aperf, mperf;
+
+	rdmsrl(MSR_IA32_APERF, aperf);
+	rdmsrl(MSR_IA32_MPERF, mperf);
+
+	this_cpu_write(cpu_samples.aperf, aperf);
+	this_cpu_write(cpu_samples.mperf, mperf);
+}
+
+#if defined(CONFIG_X86_64) && defined(CONFIG_SMP)
+/*
+ * APERF/MPERF frequency ratio computation.
+ *
+ * The scheduler wants to do frequency invariant accounting and needs a <1
+ * ratio to account for the 'current' frequency, corresponding to
+ * freq_curr / freq_max.
+ *
+ * Since the frequency freq_curr on x86 is controlled by micro-controller and
+ * our P-state setting is little more than a request/hint, we need to observe
+ * the effective frequency 'BusyMHz', i.e. the average frequency over a time
+ * interval after discarding idle time. This is given by:
+ *
+ *   BusyMHz = delta_APERF / delta_MPERF * freq_base
+ *
+ * where freq_base is the max non-turbo P-state.
+ *
+ * The freq_max term has to be set to a somewhat arbitrary value, because we
+ * can't know which turbo states will be available at a given point in time:
+ * it all depends on the thermal headroom of the entire package. We set it to
+ * the turbo level with 4 cores active.
+ *
+ * Benchmarks show that's a good compromise between the 1C turbo ratio
+ * (freq_curr/freq_max would rarely reach 1) and something close to freq_base,
+ * which would ignore the entire turbo range (a conspicuous part, making
+ * freq_curr/freq_max always maxed out).
+ *
+ * An exception to the heuristic above is the Atom uarch, where we choose the
+ * highest turbo level for freq_max since Atom's are generally oriented towards
+ * power efficiency.
+ *
+ * Setting freq_max to anything less than the 1C turbo ratio makes the ratio
+ * freq_curr / freq_max to eventually grow >1, in which case we clip it to 1.
+ */
+
+DEFINE_STATIC_KEY_FALSE(arch_scale_freq_key);
+
+static u64 arch_turbo_freq_ratio = SCHED_CAPACITY_SCALE;
+static u64 arch_max_freq_ratio = SCHED_CAPACITY_SCALE;
+
+void arch_set_max_freq_ratio(bool turbo_disabled)
+{
+	arch_max_freq_ratio = turbo_disabled ? SCHED_CAPACITY_SCALE :
+					arch_turbo_freq_ratio;
+}
+EXPORT_SYMBOL_GPL(arch_set_max_freq_ratio);
+
+static bool __init turbo_disabled(void)
+{
+	u64 misc_en;
+	int err;
+
+	err = rdmsrl_safe(MSR_IA32_MISC_ENABLE, &misc_en);
+	if (err)
+		return false;
+
+	return (misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
+}
+
+static bool __init slv_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq)
+{
+	int err;
+
+	err = rdmsrl_safe(MSR_ATOM_CORE_RATIOS, base_freq);
+	if (err)
+		return false;
+
+	err = rdmsrl_safe(MSR_ATOM_CORE_TURBO_RATIOS, turbo_freq);
+	if (err)
+		return false;
+
+	*base_freq = (*base_freq >> 16) & 0x3F;     /* max P state */
+	*turbo_freq = *turbo_freq & 0x3F;           /* 1C turbo    */
+
+	return true;
+}
+
+#define X86_MATCH(model)					\
+	X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6,		\
+		INTEL_FAM6_##model, X86_FEATURE_APERFMPERF, NULL)
+
+static const struct x86_cpu_id has_knl_turbo_ratio_limits[] __initconst = {
+	X86_MATCH(XEON_PHI_KNL),
+	X86_MATCH(XEON_PHI_KNM),
+	{}
+};
+
+static const struct x86_cpu_id has_skx_turbo_ratio_limits[] __initconst = {
+	X86_MATCH(SKYLAKE_X),
+	{}
+};
+
+static const struct x86_cpu_id has_glm_turbo_ratio_limits[] __initconst = {
+	X86_MATCH(ATOM_GOLDMONT),
+	X86_MATCH(ATOM_GOLDMONT_D),
+	X86_MATCH(ATOM_GOLDMONT_PLUS),
+	{}
+};
+
+static bool __init knl_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq,
+					  int num_delta_fratio)
+{
+	int fratio, delta_fratio, found;
+	int err, i;
+	u64 msr;
+
+	err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq);
+	if (err)
+		return false;
+
+	*base_freq = (*base_freq >> 8) & 0xFF;	    /* max P state */
+
+	err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &msr);
+	if (err)
+		return false;
+
+	fratio = (msr >> 8) & 0xFF;
+	i = 16;
+	found = 0;
+	do {
+		if (found >= num_delta_fratio) {
+			*turbo_freq = fratio;
+			return true;
+		}
+
+		delta_fratio = (msr >> (i + 5)) & 0x7;
+
+		if (delta_fratio) {
+			found += 1;
+			fratio -= delta_fratio;
+		}
+
+		i += 8;
+	} while (i < 64);
+
+	return true;
+}
+
+static bool __init skx_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq, int size)
+{
+	u64 ratios, counts;
+	u32 group_size;
+	int err, i;
+
+	err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq);
+	if (err)
+		return false;
+
+	*base_freq = (*base_freq >> 8) & 0xFF;      /* max P state */
+
+	err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &ratios);
+	if (err)
+		return false;
+
+	err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT1, &counts);
+	if (err)
+		return false;
+
+	for (i = 0; i < 64; i += 8) {
+		group_size = (counts >> i) & 0xFF;
+		if (group_size >= size) {
+			*turbo_freq = (ratios >> i) & 0xFF;
+			return true;
+		}
+	}
+
+	return false;
+}
+
+static bool __init core_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq)
+{
+	u64 msr;
+	int err;
+
+	err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq);
+	if (err)
+		return false;
+
+	err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &msr);
+	if (err)
+		return false;
+
+	*base_freq = (*base_freq >> 8) & 0xFF;    /* max P state */
+	*turbo_freq = (msr >> 24) & 0xFF;         /* 4C turbo    */
+
+	/* The CPU may have less than 4 cores */
+	if (!*turbo_freq)
+		*turbo_freq = msr & 0xFF;         /* 1C turbo    */
+
+	return true;
+}
+
+static bool __init intel_set_max_freq_ratio(void)
+{
+	u64 base_freq, turbo_freq;
+	u64 turbo_ratio;
+
+	if (slv_set_max_freq_ratio(&base_freq, &turbo_freq))
+		goto out;
+
+	if (x86_match_cpu(has_glm_turbo_ratio_limits) &&
+	    skx_set_max_freq_ratio(&base_freq, &turbo_freq, 1))
+		goto out;
+
+	if (x86_match_cpu(has_knl_turbo_ratio_limits) &&
+	    knl_set_max_freq_ratio(&base_freq, &turbo_freq, 1))
+		goto out;
+
+	if (x86_match_cpu(has_skx_turbo_ratio_limits) &&
+	    skx_set_max_freq_ratio(&base_freq, &turbo_freq, 4))
+		goto out;
+
+	if (core_set_max_freq_ratio(&base_freq, &turbo_freq))
+		goto out;
+
+	return false;
+
+out:
+	/*
+	 * Some hypervisors advertise X86_FEATURE_APERFMPERF
+	 * but then fill all MSR's with zeroes.
+	 * Some CPUs have turbo boost but don't declare any turbo ratio
+	 * in MSR_TURBO_RATIO_LIMIT.
+	 */
+	if (!base_freq || !turbo_freq) {
+		pr_debug("Couldn't determine cpu base or turbo frequency, necessary for scale-invariant accounting.\n");
+		return false;
+	}
+
+	turbo_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE, base_freq);
+	if (!turbo_ratio) {
+		pr_debug("Non-zero turbo and base frequencies led to a 0 ratio.\n");
+		return false;
+	}
+
+	arch_turbo_freq_ratio = turbo_ratio;
+	arch_set_max_freq_ratio(turbo_disabled());
+
+	return true;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static struct syscore_ops freq_invariance_syscore_ops = {
+	.resume = init_counter_refs,
+};
+
+static void register_freq_invariance_syscore_ops(void)
+{
+	register_syscore_ops(&freq_invariance_syscore_ops);
+}
+#else
+static inline void register_freq_invariance_syscore_ops(void) {}
+#endif
+
+static void freq_invariance_enable(void)
+{
+	if (static_branch_unlikely(&arch_scale_freq_key)) {
+		WARN_ON_ONCE(1);
+		return;
+	}
+	static_branch_enable(&arch_scale_freq_key);
+	register_freq_invariance_syscore_ops();
+	pr_info("Estimated ratio of average max frequency by base frequency (times 1024): %llu\n", arch_max_freq_ratio);
+}
+
+void freq_invariance_set_perf_ratio(u64 ratio, bool turbo_disabled)
+{
+	arch_turbo_freq_ratio = ratio;
+	arch_set_max_freq_ratio(turbo_disabled);
+	freq_invariance_enable();
+}
+
+static void __init bp_init_freq_invariance(void)
+{
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
+		return;
+
+	if (intel_set_max_freq_ratio())
+		freq_invariance_enable();
+}
+
+static void disable_freq_invariance_workfn(struct work_struct *work)
+{
+	int cpu;
+
+	static_branch_disable(&arch_scale_freq_key);
+
+	/*
+	 * Set arch_freq_scale to a default value on all cpus
+	 * This negates the effect of scaling
+	 */
+	for_each_possible_cpu(cpu)
+		per_cpu(arch_freq_scale, cpu) = SCHED_CAPACITY_SCALE;
+}
+
+static DECLARE_WORK(disable_freq_invariance_work,
+		    disable_freq_invariance_workfn);
+
+DEFINE_PER_CPU(unsigned long, arch_freq_scale) = SCHED_CAPACITY_SCALE;
+
+static void scale_freq_tick(u64 acnt, u64 mcnt)
+{
+	u64 freq_scale;
+
+	if (!arch_scale_freq_invariant())
+		return;
+
+	if (check_shl_overflow(acnt, 2*SCHED_CAPACITY_SHIFT, &acnt))
+		goto error;
+
+	if (check_mul_overflow(mcnt, arch_max_freq_ratio, &mcnt) || !mcnt)
+		goto error;
+
+	freq_scale = div64_u64(acnt, mcnt);
+	if (!freq_scale)
+		goto error;
+
+	if (freq_scale > SCHED_CAPACITY_SCALE)
+		freq_scale = SCHED_CAPACITY_SCALE;
+
+	this_cpu_write(arch_freq_scale, freq_scale);
+	return;
+
+error:
+	pr_warn("Scheduler frequency invariance went wobbly, disabling!\n");
+	schedule_work(&disable_freq_invariance_work);
+}
+#else
+static inline void bp_init_freq_invariance(void) { }
+static inline void scale_freq_tick(u64 acnt, u64 mcnt) { }
+#endif /* CONFIG_X86_64 && CONFIG_SMP */
+
+void arch_scale_freq_tick(void)
+{
+	struct aperfmperf *s = this_cpu_ptr(&cpu_samples);
+	u64 acnt, mcnt, aperf, mperf;
+
+	if (!cpu_feature_enabled(X86_FEATURE_APERFMPERF))
+		return;
+
+	rdmsrl(MSR_IA32_APERF, aperf);
+	rdmsrl(MSR_IA32_MPERF, mperf);
+	acnt = aperf - s->aperf;
+	mcnt = mperf - s->mperf;
+
+	s->aperf = aperf;
+	s->mperf = mperf;
+
+	raw_write_seqcount_begin(&s->seq);
+	s->last_update = jiffies;
+	s->acnt = acnt;
+	s->mcnt = mcnt;
+	raw_write_seqcount_end(&s->seq);
+
+	scale_freq_tick(acnt, mcnt);
+}
+
+/*
+ * Discard samples older than the define maximum sample age of 20ms. There
+ * is no point in sending IPIs in such a case. If the scheduler tick was
+ * not running then the CPU is either idle or isolated.
+ */
+#define MAX_SAMPLE_AGE	((unsigned long)HZ / 50)
+
+unsigned int arch_freq_get_on_cpu(int cpu)
+{
+	struct aperfmperf *s = per_cpu_ptr(&cpu_samples, cpu);
+	unsigned int seq, freq;
+	unsigned long last;
+	u64 acnt, mcnt;
+
+	if (!cpu_feature_enabled(X86_FEATURE_APERFMPERF))
+		goto fallback;
+
+	do {
+		seq = raw_read_seqcount_begin(&s->seq);
+		last = s->last_update;
+		acnt = s->acnt;
+		mcnt = s->mcnt;
+	} while (read_seqcount_retry(&s->seq, seq));
+
+	/*
+	 * Bail on invalid count and when the last update was too long ago,
+	 * which covers idle and NOHZ full CPUs.
+	 */
+	if (!mcnt || (jiffies - last) > MAX_SAMPLE_AGE)
+		goto fallback;
+
+	return div64_u64((cpu_khz * acnt), mcnt);
+
+fallback:
+	freq = cpufreq_quick_get(cpu);
+	return freq ? freq : cpu_khz;
+}
+
+static int __init bp_init_aperfmperf(void)
+{
+	if (!cpu_feature_enabled(X86_FEATURE_APERFMPERF))
+		return 0;
+
+	init_counter_refs();
+	bp_init_freq_invariance();
+	return 0;
+}
+early_initcall(bp_init_aperfmperf);
+
+void ap_init_aperfmperf(void)
+{
+	if (cpu_feature_enabled(X86_FEATURE_APERFMPERF))
+		init_counter_refs();
+}
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
new file mode 100644
index 0000000000..0bc55472f3
--- /dev/null
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -0,0 +1,2852 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  Copyright (C) 1994  Linus Torvalds
+ *
+ *  Cyrix stuff, June 1998 by:
+ *	- Rafael R. Reilova (moved everything from head.S),
+ *        <rreilova@ececs.uc.edu>
+ *	- Channing Corn (tests & fixes),
+ *	- Andrew D. Balsa (code cleanup).
+ */
+#include <linux/init.h>
+#include <linux/cpu.h>
+#include <linux/module.h>
+#include <linux/nospec.h>
+#include <linux/prctl.h>
+#include <linux/sched/smt.h>
+#include <linux/pgtable.h>
+#include <linux/bpf.h>
+
+#include <asm/spec-ctrl.h>
+#include <asm/cmdline.h>
+#include <asm/bugs.h>
+#include <asm/processor.h>
+#include <asm/processor-flags.h>
+#include <asm/fpu/api.h>
+#include <asm/msr.h>
+#include <asm/vmx.h>
+#include <asm/paravirt.h>
+#include <asm/intel-family.h>
+#include <asm/e820/api.h>
+#include <asm/hypervisor.h>
+#include <asm/tlbflush.h>
+#include <asm/cpu.h>
+
+#include "cpu.h"
+
+static void __init spectre_v1_select_mitigation(void);
+static void __init spectre_v2_select_mitigation(void);
+static void __init retbleed_select_mitigation(void);
+static void __init spectre_v2_user_select_mitigation(void);
+static void __init ssb_select_mitigation(void);
+static void __init l1tf_select_mitigation(void);
+static void __init mds_select_mitigation(void);
+static void __init md_clear_update_mitigation(void);
+static void __init md_clear_select_mitigation(void);
+static void __init taa_select_mitigation(void);
+static void __init mmio_select_mitigation(void);
+static void __init srbds_select_mitigation(void);
+static void __init l1d_flush_select_mitigation(void);
+static void __init srso_select_mitigation(void);
+static void __init gds_select_mitigation(void);
+
+/* The base value of the SPEC_CTRL MSR without task-specific bits set */
+u64 x86_spec_ctrl_base;
+EXPORT_SYMBOL_GPL(x86_spec_ctrl_base);
+
+/* The current value of the SPEC_CTRL MSR with task-specific bits set */
+DEFINE_PER_CPU(u64, x86_spec_ctrl_current);
+EXPORT_SYMBOL_GPL(x86_spec_ctrl_current);
+
+u64 x86_pred_cmd __ro_after_init = PRED_CMD_IBPB;
+EXPORT_SYMBOL_GPL(x86_pred_cmd);
+
+static DEFINE_MUTEX(spec_ctrl_mutex);
+
+void (*x86_return_thunk)(void) __ro_after_init = &__x86_return_thunk;
+
+/* Update SPEC_CTRL MSR and its cached copy unconditionally */
+static void update_spec_ctrl(u64 val)
+{
+	this_cpu_write(x86_spec_ctrl_current, val);
+	wrmsrl(MSR_IA32_SPEC_CTRL, val);
+}
+
+/*
+ * Keep track of the SPEC_CTRL MSR value for the current task, which may differ
+ * from x86_spec_ctrl_base due to STIBP/SSB in __speculation_ctrl_update().
+ */
+void update_spec_ctrl_cond(u64 val)
+{
+	if (this_cpu_read(x86_spec_ctrl_current) == val)
+		return;
+
+	this_cpu_write(x86_spec_ctrl_current, val);
+
+	/*
+	 * When KERNEL_IBRS this MSR is written on return-to-user, unless
+	 * forced the update can be delayed until that time.
+	 */
+	if (!cpu_feature_enabled(X86_FEATURE_KERNEL_IBRS))
+		wrmsrl(MSR_IA32_SPEC_CTRL, val);
+}
+
+noinstr u64 spec_ctrl_current(void)
+{
+	return this_cpu_read(x86_spec_ctrl_current);
+}
+EXPORT_SYMBOL_GPL(spec_ctrl_current);
+
+/*
+ * AMD specific MSR info for Speculative Store Bypass control.
+ * x86_amd_ls_cfg_ssbd_mask is initialized in identify_boot_cpu().
+ */
+u64 __ro_after_init x86_amd_ls_cfg_base;
+u64 __ro_after_init x86_amd_ls_cfg_ssbd_mask;
+
+/* Control conditional STIBP in switch_to() */
+DEFINE_STATIC_KEY_FALSE(switch_to_cond_stibp);
+/* Control conditional IBPB in switch_mm() */
+DEFINE_STATIC_KEY_FALSE(switch_mm_cond_ibpb);
+/* Control unconditional IBPB in switch_mm() */
+DEFINE_STATIC_KEY_FALSE(switch_mm_always_ibpb);
+
+/* Control MDS CPU buffer clear before returning to user space */
+DEFINE_STATIC_KEY_FALSE(mds_user_clear);
+EXPORT_SYMBOL_GPL(mds_user_clear);
+/* Control MDS CPU buffer clear before idling (halt, mwait) */
+DEFINE_STATIC_KEY_FALSE(mds_idle_clear);
+EXPORT_SYMBOL_GPL(mds_idle_clear);
+
+/*
+ * Controls whether l1d flush based mitigations are enabled,
+ * based on hw features and admin setting via boot parameter
+ * defaults to false
+ */
+DEFINE_STATIC_KEY_FALSE(switch_mm_cond_l1d_flush);
+
+/* Controls CPU Fill buffer clear before KVM guest MMIO accesses */
+DEFINE_STATIC_KEY_FALSE(mmio_stale_data_clear);
+EXPORT_SYMBOL_GPL(mmio_stale_data_clear);
+
+void __init cpu_select_mitigations(void)
+{
+	/*
+	 * Read the SPEC_CTRL MSR to account for reserved bits which may
+	 * have unknown values. AMD64_LS_CFG MSR is cached in the early AMD
+	 * init code as it is not enumerated and depends on the family.
+	 */
+	if (cpu_feature_enabled(X86_FEATURE_MSR_SPEC_CTRL)) {
+		rdmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);
+
+		/*
+		 * Previously running kernel (kexec), may have some controls
+		 * turned ON. Clear them and let the mitigations setup below
+		 * rediscover them based on configuration.
+		 */
+		x86_spec_ctrl_base &= ~SPEC_CTRL_MITIGATIONS_MASK;
+	}
+
+	/* Select the proper CPU mitigations before patching alternatives: */
+	spectre_v1_select_mitigation();
+	spectre_v2_select_mitigation();
+	/*
+	 * retbleed_select_mitigation() relies on the state set by
+	 * spectre_v2_select_mitigation(); specifically it wants to know about
+	 * spectre_v2=ibrs.
+	 */
+	retbleed_select_mitigation();
+	/*
+	 * spectre_v2_user_select_mitigation() relies on the state set by
+	 * retbleed_select_mitigation(); specifically the STIBP selection is
+	 * forced for UNRET or IBPB.
+	 */
+	spectre_v2_user_select_mitigation();
+	ssb_select_mitigation();
+	l1tf_select_mitigation();
+	md_clear_select_mitigation();
+	srbds_select_mitigation();
+	l1d_flush_select_mitigation();
+
+	/*
+	 * srso_select_mitigation() depends and must run after
+	 * retbleed_select_mitigation().
+	 */
+	srso_select_mitigation();
+	gds_select_mitigation();
+}
+
+/*
+ * NOTE: This function is *only* called for SVM, since Intel uses
+ * MSR_IA32_SPEC_CTRL for SSBD.
+ */
+void
+x86_virt_spec_ctrl(u64 guest_virt_spec_ctrl, bool setguest)
+{
+	u64 guestval, hostval;
+	struct thread_info *ti = current_thread_info();
+
+	/*
+	 * If SSBD is not handled in MSR_SPEC_CTRL on AMD, update
+	 * MSR_AMD64_L2_CFG or MSR_VIRT_SPEC_CTRL if supported.
+	 */
+	if (!static_cpu_has(X86_FEATURE_LS_CFG_SSBD) &&
+	    !static_cpu_has(X86_FEATURE_VIRT_SSBD))
+		return;
+
+	/*
+	 * If the host has SSBD mitigation enabled, force it in the host's
+	 * virtual MSR value. If its not permanently enabled, evaluate
+	 * current's TIF_SSBD thread flag.
+	 */
+	if (static_cpu_has(X86_FEATURE_SPEC_STORE_BYPASS_DISABLE))
+		hostval = SPEC_CTRL_SSBD;
+	else
+		hostval = ssbd_tif_to_spec_ctrl(ti->flags);
+
+	/* Sanitize the guest value */
+	guestval = guest_virt_spec_ctrl & SPEC_CTRL_SSBD;
+
+	if (hostval != guestval) {
+		unsigned long tif;
+
+		tif = setguest ? ssbd_spec_ctrl_to_tif(guestval) :
+				 ssbd_spec_ctrl_to_tif(hostval);
+
+		speculation_ctrl_update(tif);
+	}
+}
+EXPORT_SYMBOL_GPL(x86_virt_spec_ctrl);
+
+static void x86_amd_ssb_disable(void)
+{
+	u64 msrval = x86_amd_ls_cfg_base | x86_amd_ls_cfg_ssbd_mask;
+
+	if (boot_cpu_has(X86_FEATURE_VIRT_SSBD))
+		wrmsrl(MSR_AMD64_VIRT_SPEC_CTRL, SPEC_CTRL_SSBD);
+	else if (boot_cpu_has(X86_FEATURE_LS_CFG_SSBD))
+		wrmsrl(MSR_AMD64_LS_CFG, msrval);
+}
+
+#undef pr_fmt
+#define pr_fmt(fmt)	"MDS: " fmt
+
+/* Default mitigation for MDS-affected CPUs */
+static enum mds_mitigations mds_mitigation __ro_after_init = MDS_MITIGATION_FULL;
+static bool mds_nosmt __ro_after_init = false;
+
+static const char * const mds_strings[] = {
+	[MDS_MITIGATION_OFF]	= "Vulnerable",
+	[MDS_MITIGATION_FULL]	= "Mitigation: Clear CPU buffers",
+	[MDS_MITIGATION_VMWERV]	= "Vulnerable: Clear CPU buffers attempted, no microcode",
+};
+
+static void __init mds_select_mitigation(void)
+{
+	if (!boot_cpu_has_bug(X86_BUG_MDS) || cpu_mitigations_off()) {
+		mds_mitigation = MDS_MITIGATION_OFF;
+		return;
+	}
+
+	if (mds_mitigation == MDS_MITIGATION_FULL) {
+		if (!boot_cpu_has(X86_FEATURE_MD_CLEAR))
+			mds_mitigation = MDS_MITIGATION_VMWERV;
+
+		static_branch_enable(&mds_user_clear);
+
+		if (!boot_cpu_has(X86_BUG_MSBDS_ONLY) &&
+		    (mds_nosmt || cpu_mitigations_auto_nosmt()))
+			cpu_smt_disable(false);
+	}
+}
+
+static int __init mds_cmdline(char *str)
+{
+	if (!boot_cpu_has_bug(X86_BUG_MDS))
+		return 0;
+
+	if (!str)
+		return -EINVAL;
+
+	if (!strcmp(str, "off"))
+		mds_mitigation = MDS_MITIGATION_OFF;
+	else if (!strcmp(str, "full"))
+		mds_mitigation = MDS_MITIGATION_FULL;
+	else if (!strcmp(str, "full,nosmt")) {
+		mds_mitigation = MDS_MITIGATION_FULL;
+		mds_nosmt = true;
+	}
+
+	return 0;
+}
+early_param("mds", mds_cmdline);
+
+#undef pr_fmt
+#define pr_fmt(fmt)	"TAA: " fmt
+
+enum taa_mitigations {
+	TAA_MITIGATION_OFF,
+	TAA_MITIGATION_UCODE_NEEDED,
+	TAA_MITIGATION_VERW,
+	TAA_MITIGATION_TSX_DISABLED,
+};
+
+/* Default mitigation for TAA-affected CPUs */
+static enum taa_mitigations taa_mitigation __ro_after_init = TAA_MITIGATION_VERW;
+static bool taa_nosmt __ro_after_init;
+
+static const char * const taa_strings[] = {
+	[TAA_MITIGATION_OFF]		= "Vulnerable",
+	[TAA_MITIGATION_UCODE_NEEDED]	= "Vulnerable: Clear CPU buffers attempted, no microcode",
+	[TAA_MITIGATION_VERW]		= "Mitigation: Clear CPU buffers",
+	[TAA_MITIGATION_TSX_DISABLED]	= "Mitigation: TSX disabled",
+};
+
+static void __init taa_select_mitigation(void)
+{
+	u64 ia32_cap;
+
+	if (!boot_cpu_has_bug(X86_BUG_TAA)) {
+		taa_mitigation = TAA_MITIGATION_OFF;
+		return;
+	}
+
+	/* TSX previously disabled by tsx=off */
+	if (!boot_cpu_has(X86_FEATURE_RTM)) {
+		taa_mitigation = TAA_MITIGATION_TSX_DISABLED;
+		return;
+	}
+
+	if (cpu_mitigations_off()) {
+		taa_mitigation = TAA_MITIGATION_OFF;
+		return;
+	}
+
+	/*
+	 * TAA mitigation via VERW is turned off if both
+	 * tsx_async_abort=off and mds=off are specified.
+	 */
+	if (taa_mitigation == TAA_MITIGATION_OFF &&
+	    mds_mitigation == MDS_MITIGATION_OFF)
+		return;
+
+	if (boot_cpu_has(X86_FEATURE_MD_CLEAR))
+		taa_mitigation = TAA_MITIGATION_VERW;
+	else
+		taa_mitigation = TAA_MITIGATION_UCODE_NEEDED;
+
+	/*
+	 * VERW doesn't clear the CPU buffers when MD_CLEAR=1 and MDS_NO=1.
+	 * A microcode update fixes this behavior to clear CPU buffers. It also
+	 * adds support for MSR_IA32_TSX_CTRL which is enumerated by the
+	 * ARCH_CAP_TSX_CTRL_MSR bit.
+	 *
+	 * On MDS_NO=1 CPUs if ARCH_CAP_TSX_CTRL_MSR is not set, microcode
+	 * update is required.
+	 */
+	ia32_cap = x86_read_arch_cap_msr();
+	if ( (ia32_cap & ARCH_CAP_MDS_NO) &&
+	    !(ia32_cap & ARCH_CAP_TSX_CTRL_MSR))
+		taa_mitigation = TAA_MITIGATION_UCODE_NEEDED;
+
+	/*
+	 * TSX is enabled, select alternate mitigation for TAA which is
+	 * the same as MDS. Enable MDS static branch to clear CPU buffers.
+	 *
+	 * For guests that can't determine whether the correct microcode is
+	 * present on host, enable the mitigation for UCODE_NEEDED as well.
+	 */
+	static_branch_enable(&mds_user_clear);
+
+	if (taa_nosmt || cpu_mitigations_auto_nosmt())
+		cpu_smt_disable(false);
+}
+
+static int __init tsx_async_abort_parse_cmdline(char *str)
+{
+	if (!boot_cpu_has_bug(X86_BUG_TAA))
+		return 0;
+
+	if (!str)
+		return -EINVAL;
+
+	if (!strcmp(str, "off")) {
+		taa_mitigation = TAA_MITIGATION_OFF;
+	} else if (!strcmp(str, "full")) {
+		taa_mitigation = TAA_MITIGATION_VERW;
+	} else if (!strcmp(str, "full,nosmt")) {
+		taa_mitigation = TAA_MITIGATION_VERW;
+		taa_nosmt = true;
+	}
+
+	return 0;
+}
+early_param("tsx_async_abort", tsx_async_abort_parse_cmdline);
+
+#undef pr_fmt
+#define pr_fmt(fmt)	"MMIO Stale Data: " fmt
+
+enum mmio_mitigations {
+	MMIO_MITIGATION_OFF,
+	MMIO_MITIGATION_UCODE_NEEDED,
+	MMIO_MITIGATION_VERW,
+};
+
+/* Default mitigation for Processor MMIO Stale Data vulnerabilities */
+static enum mmio_mitigations mmio_mitigation __ro_after_init = MMIO_MITIGATION_VERW;
+static bool mmio_nosmt __ro_after_init = false;
+
+static const char * const mmio_strings[] = {
+	[MMIO_MITIGATION_OFF]		= "Vulnerable",
+	[MMIO_MITIGATION_UCODE_NEEDED]	= "Vulnerable: Clear CPU buffers attempted, no microcode",
+	[MMIO_MITIGATION_VERW]		= "Mitigation: Clear CPU buffers",
+};
+
+static void __init mmio_select_mitigation(void)
+{
+	u64 ia32_cap;
+
+	if (!boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA) ||
+	     boot_cpu_has_bug(X86_BUG_MMIO_UNKNOWN) ||
+	     cpu_mitigations_off()) {
+		mmio_mitigation = MMIO_MITIGATION_OFF;
+		return;
+	}
+
+	if (mmio_mitigation == MMIO_MITIGATION_OFF)
+		return;
+
+	ia32_cap = x86_read_arch_cap_msr();
+
+	/*
+	 * Enable CPU buffer clear mitigation for host and VMM, if also affected
+	 * by MDS or TAA. Otherwise, enable mitigation for VMM only.
+	 */
+	if (boot_cpu_has_bug(X86_BUG_MDS) || (boot_cpu_has_bug(X86_BUG_TAA) &&
+					      boot_cpu_has(X86_FEATURE_RTM)))
+		static_branch_enable(&mds_user_clear);
+	else
+		static_branch_enable(&mmio_stale_data_clear);
+
+	/*
+	 * If Processor-MMIO-Stale-Data bug is present and Fill Buffer data can
+	 * be propagated to uncore buffers, clearing the Fill buffers on idle
+	 * is required irrespective of SMT state.
+	 */
+	if (!(ia32_cap & ARCH_CAP_FBSDP_NO))
+		static_branch_enable(&mds_idle_clear);
+
+	/*
+	 * Check if the system has the right microcode.
+	 *
+	 * CPU Fill buffer clear mitigation is enumerated by either an explicit
+	 * FB_CLEAR or by the presence of both MD_CLEAR and L1D_FLUSH on MDS
+	 * affected systems.
+	 */
+	if ((ia32_cap & ARCH_CAP_FB_CLEAR) ||
+	    (boot_cpu_has(X86_FEATURE_MD_CLEAR) &&
+	     boot_cpu_has(X86_FEATURE_FLUSH_L1D) &&
+	     !(ia32_cap & ARCH_CAP_MDS_NO)))
+		mmio_mitigation = MMIO_MITIGATION_VERW;
+	else
+		mmio_mitigation = MMIO_MITIGATION_UCODE_NEEDED;
+
+	if (mmio_nosmt || cpu_mitigations_auto_nosmt())
+		cpu_smt_disable(false);
+}
+
+static int __init mmio_stale_data_parse_cmdline(char *str)
+{
+	if (!boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA))
+		return 0;
+
+	if (!str)
+		return -EINVAL;
+
+	if (!strcmp(str, "off")) {
+		mmio_mitigation = MMIO_MITIGATION_OFF;
+	} else if (!strcmp(str, "full")) {
+		mmio_mitigation = MMIO_MITIGATION_VERW;
+	} else if (!strcmp(str, "full,nosmt")) {
+		mmio_mitigation = MMIO_MITIGATION_VERW;
+		mmio_nosmt = true;
+	}
+
+	return 0;
+}
+early_param("mmio_stale_data", mmio_stale_data_parse_cmdline);
+
+#undef pr_fmt
+#define pr_fmt(fmt)     "" fmt
+
+static void __init md_clear_update_mitigation(void)
+{
+	if (cpu_mitigations_off())
+		return;
+
+	if (!static_key_enabled(&mds_user_clear))
+		goto out;
+
+	/*
+	 * mds_user_clear is now enabled. Update MDS, TAA and MMIO Stale Data
+	 * mitigation, if necessary.
+	 */
+	if (mds_mitigation == MDS_MITIGATION_OFF &&
+	    boot_cpu_has_bug(X86_BUG_MDS)) {
+		mds_mitigation = MDS_MITIGATION_FULL;
+		mds_select_mitigation();
+	}
+	if (taa_mitigation == TAA_MITIGATION_OFF &&
+	    boot_cpu_has_bug(X86_BUG_TAA)) {
+		taa_mitigation = TAA_MITIGATION_VERW;
+		taa_select_mitigation();
+	}
+	if (mmio_mitigation == MMIO_MITIGATION_OFF &&
+	    boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA)) {
+		mmio_mitigation = MMIO_MITIGATION_VERW;
+		mmio_select_mitigation();
+	}
+out:
+	if (boot_cpu_has_bug(X86_BUG_MDS))
+		pr_info("MDS: %s\n", mds_strings[mds_mitigation]);
+	if (boot_cpu_has_bug(X86_BUG_TAA))
+		pr_info("TAA: %s\n", taa_strings[taa_mitigation]);
+	if (boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA))
+		pr_info("MMIO Stale Data: %s\n", mmio_strings[mmio_mitigation]);
+	else if (boot_cpu_has_bug(X86_BUG_MMIO_UNKNOWN))
+		pr_info("MMIO Stale Data: Unknown: No mitigations\n");
+}
+
+static void __init md_clear_select_mitigation(void)
+{
+	mds_select_mitigation();
+	taa_select_mitigation();
+	mmio_select_mitigation();
+
+	/*
+	 * As MDS, TAA and MMIO Stale Data mitigations are inter-related, update
+	 * and print their mitigation after MDS, TAA and MMIO Stale Data
+	 * mitigation selection is done.
+	 */
+	md_clear_update_mitigation();
+}
+
+#undef pr_fmt
+#define pr_fmt(fmt)	"SRBDS: " fmt
+
+enum srbds_mitigations {
+	SRBDS_MITIGATION_OFF,
+	SRBDS_MITIGATION_UCODE_NEEDED,
+	SRBDS_MITIGATION_FULL,
+	SRBDS_MITIGATION_TSX_OFF,
+	SRBDS_MITIGATION_HYPERVISOR,
+};
+
+static enum srbds_mitigations srbds_mitigation __ro_after_init = SRBDS_MITIGATION_FULL;
+
+static const char * const srbds_strings[] = {
+	[SRBDS_MITIGATION_OFF]		= "Vulnerable",
+	[SRBDS_MITIGATION_UCODE_NEEDED]	= "Vulnerable: No microcode",
+	[SRBDS_MITIGATION_FULL]		= "Mitigation: Microcode",
+	[SRBDS_MITIGATION_TSX_OFF]	= "Mitigation: TSX disabled",
+	[SRBDS_MITIGATION_HYPERVISOR]	= "Unknown: Dependent on hypervisor status",
+};
+
+static bool srbds_off;
+
+void update_srbds_msr(void)
+{
+	u64 mcu_ctrl;
+
+	if (!boot_cpu_has_bug(X86_BUG_SRBDS))
+		return;
+
+	if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
+		return;
+
+	if (srbds_mitigation == SRBDS_MITIGATION_UCODE_NEEDED)
+		return;
+
+	/*
+	 * A MDS_NO CPU for which SRBDS mitigation is not needed due to TSX
+	 * being disabled and it hasn't received the SRBDS MSR microcode.
+	 */
+	if (!boot_cpu_has(X86_FEATURE_SRBDS_CTRL))
+		return;
+
+	rdmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
+
+	switch (srbds_mitigation) {
+	case SRBDS_MITIGATION_OFF:
+	case SRBDS_MITIGATION_TSX_OFF:
+		mcu_ctrl |= RNGDS_MITG_DIS;
+		break;
+	case SRBDS_MITIGATION_FULL:
+		mcu_ctrl &= ~RNGDS_MITG_DIS;
+		break;
+	default:
+		break;
+	}
+
+	wrmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
+}
+
+static void __init srbds_select_mitigation(void)
+{
+	u64 ia32_cap;
+
+	if (!boot_cpu_has_bug(X86_BUG_SRBDS))
+		return;
+
+	/*
+	 * Check to see if this is one of the MDS_NO systems supporting TSX that
+	 * are only exposed to SRBDS when TSX is enabled or when CPU is affected
+	 * by Processor MMIO Stale Data vulnerability.
+	 */
+	ia32_cap = x86_read_arch_cap_msr();
+	if ((ia32_cap & ARCH_CAP_MDS_NO) && !boot_cpu_has(X86_FEATURE_RTM) &&
+	    !boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA))
+		srbds_mitigation = SRBDS_MITIGATION_TSX_OFF;
+	else if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
+		srbds_mitigation = SRBDS_MITIGATION_HYPERVISOR;
+	else if (!boot_cpu_has(X86_FEATURE_SRBDS_CTRL))
+		srbds_mitigation = SRBDS_MITIGATION_UCODE_NEEDED;
+	else if (cpu_mitigations_off() || srbds_off)
+		srbds_mitigation = SRBDS_MITIGATION_OFF;
+
+	update_srbds_msr();
+	pr_info("%s\n", srbds_strings[srbds_mitigation]);
+}
+
+static int __init srbds_parse_cmdline(char *str)
+{
+	if (!str)
+		return -EINVAL;
+
+	if (!boot_cpu_has_bug(X86_BUG_SRBDS))
+		return 0;
+
+	srbds_off = !strcmp(str, "off");
+	return 0;
+}
+early_param("srbds", srbds_parse_cmdline);
+
+#undef pr_fmt
+#define pr_fmt(fmt)     "L1D Flush : " fmt
+
+enum l1d_flush_mitigations {
+	L1D_FLUSH_OFF = 0,
+	L1D_FLUSH_ON,
+};
+
+static enum l1d_flush_mitigations l1d_flush_mitigation __initdata = L1D_FLUSH_OFF;
+
+static void __init l1d_flush_select_mitigation(void)
+{
+	if (!l1d_flush_mitigation || !boot_cpu_has(X86_FEATURE_FLUSH_L1D))
+		return;
+
+	static_branch_enable(&switch_mm_cond_l1d_flush);
+	pr_info("Conditional flush on switch_mm() enabled\n");
+}
+
+static int __init l1d_flush_parse_cmdline(char *str)
+{
+	if (!strcmp(str, "on"))
+		l1d_flush_mitigation = L1D_FLUSH_ON;
+
+	return 0;
+}
+early_param("l1d_flush", l1d_flush_parse_cmdline);
+
+#undef pr_fmt
+#define pr_fmt(fmt)	"GDS: " fmt
+
+enum gds_mitigations {
+	GDS_MITIGATION_OFF,
+	GDS_MITIGATION_UCODE_NEEDED,
+	GDS_MITIGATION_FORCE,
+	GDS_MITIGATION_FULL,
+	GDS_MITIGATION_FULL_LOCKED,
+	GDS_MITIGATION_HYPERVISOR,
+};
+
+#if IS_ENABLED(CONFIG_GDS_FORCE_MITIGATION)
+static enum gds_mitigations gds_mitigation __ro_after_init = GDS_MITIGATION_FORCE;
+#else
+static enum gds_mitigations gds_mitigation __ro_after_init = GDS_MITIGATION_FULL;
+#endif
+
+static const char * const gds_strings[] = {
+	[GDS_MITIGATION_OFF]		= "Vulnerable",
+	[GDS_MITIGATION_UCODE_NEEDED]	= "Vulnerable: No microcode",
+	[GDS_MITIGATION_FORCE]		= "Mitigation: AVX disabled, no microcode",
+	[GDS_MITIGATION_FULL]		= "Mitigation: Microcode",
+	[GDS_MITIGATION_FULL_LOCKED]	= "Mitigation: Microcode (locked)",
+	[GDS_MITIGATION_HYPERVISOR]	= "Unknown: Dependent on hypervisor status",
+};
+
+bool gds_ucode_mitigated(void)
+{
+	return (gds_mitigation == GDS_MITIGATION_FULL ||
+		gds_mitigation == GDS_MITIGATION_FULL_LOCKED);
+}
+EXPORT_SYMBOL_GPL(gds_ucode_mitigated);
+
+void update_gds_msr(void)
+{
+	u64 mcu_ctrl_after;
+	u64 mcu_ctrl;
+
+	switch (gds_mitigation) {
+	case GDS_MITIGATION_OFF:
+		rdmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
+		mcu_ctrl |= GDS_MITG_DIS;
+		break;
+	case GDS_MITIGATION_FULL_LOCKED:
+		/*
+		 * The LOCKED state comes from the boot CPU. APs might not have
+		 * the same state. Make sure the mitigation is enabled on all
+		 * CPUs.
+		 */
+	case GDS_MITIGATION_FULL:
+		rdmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
+		mcu_ctrl &= ~GDS_MITG_DIS;
+		break;
+	case GDS_MITIGATION_FORCE:
+	case GDS_MITIGATION_UCODE_NEEDED:
+	case GDS_MITIGATION_HYPERVISOR:
+		return;
+	};
+
+	wrmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
+
+	/*
+	 * Check to make sure that the WRMSR value was not ignored. Writes to
+	 * GDS_MITG_DIS will be ignored if this processor is locked but the boot
+	 * processor was not.
+	 */
+	rdmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl_after);
+	WARN_ON_ONCE(mcu_ctrl != mcu_ctrl_after);
+}
+
+static void __init gds_select_mitigation(void)
+{
+	u64 mcu_ctrl;
+
+	if (!boot_cpu_has_bug(X86_BUG_GDS))
+		return;
+
+	if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
+		gds_mitigation = GDS_MITIGATION_HYPERVISOR;
+		goto out;
+	}
+
+	if (cpu_mitigations_off())
+		gds_mitigation = GDS_MITIGATION_OFF;
+	/* Will verify below that mitigation _can_ be disabled */
+
+	/* No microcode */
+	if (!(x86_read_arch_cap_msr() & ARCH_CAP_GDS_CTRL)) {
+		if (gds_mitigation == GDS_MITIGATION_FORCE) {
+			/*
+			 * This only needs to be done on the boot CPU so do it
+			 * here rather than in update_gds_msr()
+			 */
+			setup_clear_cpu_cap(X86_FEATURE_AVX);
+			pr_warn("Microcode update needed! Disabling AVX as mitigation.\n");
+		} else {
+			gds_mitigation = GDS_MITIGATION_UCODE_NEEDED;
+		}
+		goto out;
+	}
+
+	/* Microcode has mitigation, use it */
+	if (gds_mitigation == GDS_MITIGATION_FORCE)
+		gds_mitigation = GDS_MITIGATION_FULL;
+
+	rdmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
+	if (mcu_ctrl & GDS_MITG_LOCKED) {
+		if (gds_mitigation == GDS_MITIGATION_OFF)
+			pr_warn("Mitigation locked. Disable failed.\n");
+
+		/*
+		 * The mitigation is selected from the boot CPU. All other CPUs
+		 * _should_ have the same state. If the boot CPU isn't locked
+		 * but others are then update_gds_msr() will WARN() of the state
+		 * mismatch. If the boot CPU is locked update_gds_msr() will
+		 * ensure the other CPUs have the mitigation enabled.
+		 */
+		gds_mitigation = GDS_MITIGATION_FULL_LOCKED;
+	}
+
+	update_gds_msr();
+out:
+	pr_info("%s\n", gds_strings[gds_mitigation]);
+}
+
+static int __init gds_parse_cmdline(char *str)
+{
+	if (!str)
+		return -EINVAL;
+
+	if (!boot_cpu_has_bug(X86_BUG_GDS))
+		return 0;
+
+	if (!strcmp(str, "off"))
+		gds_mitigation = GDS_MITIGATION_OFF;
+	else if (!strcmp(str, "force"))
+		gds_mitigation = GDS_MITIGATION_FORCE;
+
+	return 0;
+}
+early_param("gather_data_sampling", gds_parse_cmdline);
+
+#undef pr_fmt
+#define pr_fmt(fmt)     "Spectre V1 : " fmt
+
+enum spectre_v1_mitigation {
+	SPECTRE_V1_MITIGATION_NONE,
+	SPECTRE_V1_MITIGATION_AUTO,
+};
+
+static enum spectre_v1_mitigation spectre_v1_mitigation __ro_after_init =
+	SPECTRE_V1_MITIGATION_AUTO;
+
+static const char * const spectre_v1_strings[] = {
+	[SPECTRE_V1_MITIGATION_NONE] = "Vulnerable: __user pointer sanitization and usercopy barriers only; no swapgs barriers",
+	[SPECTRE_V1_MITIGATION_AUTO] = "Mitigation: usercopy/swapgs barriers and __user pointer sanitization",
+};
+
+/*
+ * Does SMAP provide full mitigation against speculative kernel access to
+ * userspace?
+ */
+static bool smap_works_speculatively(void)
+{
+	if (!boot_cpu_has(X86_FEATURE_SMAP))
+		return false;
+
+	/*
+	 * On CPUs which are vulnerable to Meltdown, SMAP does not
+	 * prevent speculative access to user data in the L1 cache.
+	 * Consider SMAP to be non-functional as a mitigation on these
+	 * CPUs.
+	 */
+	if (boot_cpu_has(X86_BUG_CPU_MELTDOWN))
+		return false;
+
+	return true;
+}
+
+static void __init spectre_v1_select_mitigation(void)
+{
+	if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1) || cpu_mitigations_off()) {
+		spectre_v1_mitigation = SPECTRE_V1_MITIGATION_NONE;
+		return;
+	}
+
+	if (spectre_v1_mitigation == SPECTRE_V1_MITIGATION_AUTO) {
+		/*
+		 * With Spectre v1, a user can speculatively control either
+		 * path of a conditional swapgs with a user-controlled GS
+		 * value.  The mitigation is to add lfences to both code paths.
+		 *
+		 * If FSGSBASE is enabled, the user can put a kernel address in
+		 * GS, in which case SMAP provides no protection.
+		 *
+		 * If FSGSBASE is disabled, the user can only put a user space
+		 * address in GS.  That makes an attack harder, but still
+		 * possible if there's no SMAP protection.
+		 */
+		if (boot_cpu_has(X86_FEATURE_FSGSBASE) ||
+		    !smap_works_speculatively()) {
+			/*
+			 * Mitigation can be provided from SWAPGS itself or
+			 * PTI as the CR3 write in the Meltdown mitigation
+			 * is serializing.
+			 *
+			 * If neither is there, mitigate with an LFENCE to
+			 * stop speculation through swapgs.
+			 */
+			if (boot_cpu_has_bug(X86_BUG_SWAPGS) &&
+			    !boot_cpu_has(X86_FEATURE_PTI))
+				setup_force_cpu_cap(X86_FEATURE_FENCE_SWAPGS_USER);
+
+			/*
+			 * Enable lfences in the kernel entry (non-swapgs)
+			 * paths, to prevent user entry from speculatively
+			 * skipping swapgs.
+			 */
+			setup_force_cpu_cap(X86_FEATURE_FENCE_SWAPGS_KERNEL);
+		}
+	}
+
+	pr_info("%s\n", spectre_v1_strings[spectre_v1_mitigation]);
+}
+
+static int __init nospectre_v1_cmdline(char *str)
+{
+	spectre_v1_mitigation = SPECTRE_V1_MITIGATION_NONE;
+	return 0;
+}
+early_param("nospectre_v1", nospectre_v1_cmdline);
+
+enum spectre_v2_mitigation spectre_v2_enabled __ro_after_init = SPECTRE_V2_NONE;
+
+#undef pr_fmt
+#define pr_fmt(fmt)     "RETBleed: " fmt
+
+enum retbleed_mitigation {
+	RETBLEED_MITIGATION_NONE,
+	RETBLEED_MITIGATION_UNRET,
+	RETBLEED_MITIGATION_IBPB,
+	RETBLEED_MITIGATION_IBRS,
+	RETBLEED_MITIGATION_EIBRS,
+	RETBLEED_MITIGATION_STUFF,
+};
+
+enum retbleed_mitigation_cmd {
+	RETBLEED_CMD_OFF,
+	RETBLEED_CMD_AUTO,
+	RETBLEED_CMD_UNRET,
+	RETBLEED_CMD_IBPB,
+	RETBLEED_CMD_STUFF,
+};
+
+static const char * const retbleed_strings[] = {
+	[RETBLEED_MITIGATION_NONE]	= "Vulnerable",
+	[RETBLEED_MITIGATION_UNRET]	= "Mitigation: untrained return thunk",
+	[RETBLEED_MITIGATION_IBPB]	= "Mitigation: IBPB",
+	[RETBLEED_MITIGATION_IBRS]	= "Mitigation: IBRS",
+	[RETBLEED_MITIGATION_EIBRS]	= "Mitigation: Enhanced IBRS",
+	[RETBLEED_MITIGATION_STUFF]	= "Mitigation: Stuffing",
+};
+
+static enum retbleed_mitigation retbleed_mitigation __ro_after_init =
+	RETBLEED_MITIGATION_NONE;
+static enum retbleed_mitigation_cmd retbleed_cmd __ro_after_init =
+	RETBLEED_CMD_AUTO;
+
+static int __ro_after_init retbleed_nosmt = false;
+
+static int __init retbleed_parse_cmdline(char *str)
+{
+	if (!str)
+		return -EINVAL;
+
+	while (str) {
+		char *next = strchr(str, ',');
+		if (next) {
+			*next = 0;
+			next++;
+		}
+
+		if (!strcmp(str, "off")) {
+			retbleed_cmd = RETBLEED_CMD_OFF;
+		} else if (!strcmp(str, "auto")) {
+			retbleed_cmd = RETBLEED_CMD_AUTO;
+		} else if (!strcmp(str, "unret")) {
+			retbleed_cmd = RETBLEED_CMD_UNRET;
+		} else if (!strcmp(str, "ibpb")) {
+			retbleed_cmd = RETBLEED_CMD_IBPB;
+		} else if (!strcmp(str, "stuff")) {
+			retbleed_cmd = RETBLEED_CMD_STUFF;
+		} else if (!strcmp(str, "nosmt")) {
+			retbleed_nosmt = true;
+		} else if (!strcmp(str, "force")) {
+			setup_force_cpu_bug(X86_BUG_RETBLEED);
+		} else {
+			pr_err("Ignoring unknown retbleed option (%s).", str);
+		}
+
+		str = next;
+	}
+
+	return 0;
+}
+early_param("retbleed", retbleed_parse_cmdline);
+
+#define RETBLEED_UNTRAIN_MSG "WARNING: BTB untrained return thunk mitigation is only effective on AMD/Hygon!\n"
+#define RETBLEED_INTEL_MSG "WARNING: Spectre v2 mitigation leaves CPU vulnerable to RETBleed attacks, data leaks possible!\n"
+
+static void __init retbleed_select_mitigation(void)
+{
+	bool mitigate_smt = false;
+
+	if (!boot_cpu_has_bug(X86_BUG_RETBLEED) || cpu_mitigations_off())
+		return;
+
+	switch (retbleed_cmd) {
+	case RETBLEED_CMD_OFF:
+		return;
+
+	case RETBLEED_CMD_UNRET:
+		if (IS_ENABLED(CONFIG_CPU_UNRET_ENTRY)) {
+			retbleed_mitigation = RETBLEED_MITIGATION_UNRET;
+		} else {
+			pr_err("WARNING: kernel not compiled with CPU_UNRET_ENTRY.\n");
+			goto do_cmd_auto;
+		}
+		break;
+
+	case RETBLEED_CMD_IBPB:
+		if (!boot_cpu_has(X86_FEATURE_IBPB)) {
+			pr_err("WARNING: CPU does not support IBPB.\n");
+			goto do_cmd_auto;
+		} else if (IS_ENABLED(CONFIG_CPU_IBPB_ENTRY)) {
+			retbleed_mitigation = RETBLEED_MITIGATION_IBPB;
+		} else {
+			pr_err("WARNING: kernel not compiled with CPU_IBPB_ENTRY.\n");
+			goto do_cmd_auto;
+		}
+		break;
+
+	case RETBLEED_CMD_STUFF:
+		if (IS_ENABLED(CONFIG_CALL_DEPTH_TRACKING) &&
+		    spectre_v2_enabled == SPECTRE_V2_RETPOLINE) {
+			retbleed_mitigation = RETBLEED_MITIGATION_STUFF;
+
+		} else {
+			if (IS_ENABLED(CONFIG_CALL_DEPTH_TRACKING))
+				pr_err("WARNING: retbleed=stuff depends on spectre_v2=retpoline\n");
+			else
+				pr_err("WARNING: kernel not compiled with CALL_DEPTH_TRACKING.\n");
+
+			goto do_cmd_auto;
+		}
+		break;
+
+do_cmd_auto:
+	case RETBLEED_CMD_AUTO:
+	default:
+		if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
+		    boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
+			if (IS_ENABLED(CONFIG_CPU_UNRET_ENTRY))
+				retbleed_mitigation = RETBLEED_MITIGATION_UNRET;
+			else if (IS_ENABLED(CONFIG_CPU_IBPB_ENTRY) && boot_cpu_has(X86_FEATURE_IBPB))
+				retbleed_mitigation = RETBLEED_MITIGATION_IBPB;
+		}
+
+		/*
+		 * The Intel mitigation (IBRS or eIBRS) was already selected in
+		 * spectre_v2_select_mitigation().  'retbleed_mitigation' will
+		 * be set accordingly below.
+		 */
+
+		break;
+	}
+
+	switch (retbleed_mitigation) {
+	case RETBLEED_MITIGATION_UNRET:
+		setup_force_cpu_cap(X86_FEATURE_RETHUNK);
+		setup_force_cpu_cap(X86_FEATURE_UNRET);
+
+		if (IS_ENABLED(CONFIG_RETHUNK))
+			x86_return_thunk = retbleed_return_thunk;
+
+		if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
+		    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
+			pr_err(RETBLEED_UNTRAIN_MSG);
+
+		mitigate_smt = true;
+		break;
+
+	case RETBLEED_MITIGATION_IBPB:
+		setup_force_cpu_cap(X86_FEATURE_ENTRY_IBPB);
+		setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT);
+		mitigate_smt = true;
+		break;
+
+	case RETBLEED_MITIGATION_STUFF:
+		setup_force_cpu_cap(X86_FEATURE_RETHUNK);
+		setup_force_cpu_cap(X86_FEATURE_CALL_DEPTH);
+		x86_set_skl_return_thunk();
+		break;
+
+	default:
+		break;
+	}
+
+	if (mitigate_smt && !boot_cpu_has(X86_FEATURE_STIBP) &&
+	    (retbleed_nosmt || cpu_mitigations_auto_nosmt()))
+		cpu_smt_disable(false);
+
+	/*
+	 * Let IBRS trump all on Intel without affecting the effects of the
+	 * retbleed= cmdline option except for call depth based stuffing
+	 */
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) {
+		switch (spectre_v2_enabled) {
+		case SPECTRE_V2_IBRS:
+			retbleed_mitigation = RETBLEED_MITIGATION_IBRS;
+			break;
+		case SPECTRE_V2_EIBRS:
+		case SPECTRE_V2_EIBRS_RETPOLINE:
+		case SPECTRE_V2_EIBRS_LFENCE:
+			retbleed_mitigation = RETBLEED_MITIGATION_EIBRS;
+			break;
+		default:
+			if (retbleed_mitigation != RETBLEED_MITIGATION_STUFF)
+				pr_err(RETBLEED_INTEL_MSG);
+		}
+	}
+
+	pr_info("%s\n", retbleed_strings[retbleed_mitigation]);
+}
+
+#undef pr_fmt
+#define pr_fmt(fmt)     "Spectre V2 : " fmt
+
+static enum spectre_v2_user_mitigation spectre_v2_user_stibp __ro_after_init =
+	SPECTRE_V2_USER_NONE;
+static enum spectre_v2_user_mitigation spectre_v2_user_ibpb __ro_after_init =
+	SPECTRE_V2_USER_NONE;
+
+#ifdef CONFIG_RETPOLINE
+static bool spectre_v2_bad_module;
+
+bool retpoline_module_ok(bool has_retpoline)
+{
+	if (spectre_v2_enabled == SPECTRE_V2_NONE || has_retpoline)
+		return true;
+
+	pr_err("System may be vulnerable to spectre v2\n");
+	spectre_v2_bad_module = true;
+	return false;
+}
+
+static inline const char *spectre_v2_module_string(void)
+{
+	return spectre_v2_bad_module ? " - vulnerable module loaded" : "";
+}
+#else
+static inline const char *spectre_v2_module_string(void) { return ""; }
+#endif
+
+#define SPECTRE_V2_LFENCE_MSG "WARNING: LFENCE mitigation is not recommended for this CPU, data leaks possible!\n"
+#define SPECTRE_V2_EIBRS_EBPF_MSG "WARNING: Unprivileged eBPF is enabled with eIBRS on, data leaks possible via Spectre v2 BHB attacks!\n"
+#define SPECTRE_V2_EIBRS_LFENCE_EBPF_SMT_MSG "WARNING: Unprivileged eBPF is enabled with eIBRS+LFENCE mitigation and SMT, data leaks possible via Spectre v2 BHB attacks!\n"
+#define SPECTRE_V2_IBRS_PERF_MSG "WARNING: IBRS mitigation selected on Enhanced IBRS CPU, this may cause unnecessary performance loss\n"
+
+#ifdef CONFIG_BPF_SYSCALL
+void unpriv_ebpf_notify(int new_state)
+{
+	if (new_state)
+		return;
+
+	/* Unprivileged eBPF is enabled */
+
+	switch (spectre_v2_enabled) {
+	case SPECTRE_V2_EIBRS:
+		pr_err(SPECTRE_V2_EIBRS_EBPF_MSG);
+		break;
+	case SPECTRE_V2_EIBRS_LFENCE:
+		if (sched_smt_active())
+			pr_err(SPECTRE_V2_EIBRS_LFENCE_EBPF_SMT_MSG);
+		break;
+	default:
+		break;
+	}
+}
+#endif
+
+static inline bool match_option(const char *arg, int arglen, const char *opt)
+{
+	int len = strlen(opt);
+
+	return len == arglen && !strncmp(arg, opt, len);
+}
+
+/* The kernel command line selection for spectre v2 */
+enum spectre_v2_mitigation_cmd {
+	SPECTRE_V2_CMD_NONE,
+	SPECTRE_V2_CMD_AUTO,
+	SPECTRE_V2_CMD_FORCE,
+	SPECTRE_V2_CMD_RETPOLINE,
+	SPECTRE_V2_CMD_RETPOLINE_GENERIC,
+	SPECTRE_V2_CMD_RETPOLINE_LFENCE,
+	SPECTRE_V2_CMD_EIBRS,
+	SPECTRE_V2_CMD_EIBRS_RETPOLINE,
+	SPECTRE_V2_CMD_EIBRS_LFENCE,
+	SPECTRE_V2_CMD_IBRS,
+};
+
+enum spectre_v2_user_cmd {
+	SPECTRE_V2_USER_CMD_NONE,
+	SPECTRE_V2_USER_CMD_AUTO,
+	SPECTRE_V2_USER_CMD_FORCE,
+	SPECTRE_V2_USER_CMD_PRCTL,
+	SPECTRE_V2_USER_CMD_PRCTL_IBPB,
+	SPECTRE_V2_USER_CMD_SECCOMP,
+	SPECTRE_V2_USER_CMD_SECCOMP_IBPB,
+};
+
+static const char * const spectre_v2_user_strings[] = {
+	[SPECTRE_V2_USER_NONE]			= "User space: Vulnerable",
+	[SPECTRE_V2_USER_STRICT]		= "User space: Mitigation: STIBP protection",
+	[SPECTRE_V2_USER_STRICT_PREFERRED]	= "User space: Mitigation: STIBP always-on protection",
+	[SPECTRE_V2_USER_PRCTL]			= "User space: Mitigation: STIBP via prctl",
+	[SPECTRE_V2_USER_SECCOMP]		= "User space: Mitigation: STIBP via seccomp and prctl",
+};
+
+static const struct {
+	const char			*option;
+	enum spectre_v2_user_cmd	cmd;
+	bool				secure;
+} v2_user_options[] __initconst = {
+	{ "auto",		SPECTRE_V2_USER_CMD_AUTO,		false },
+	{ "off",		SPECTRE_V2_USER_CMD_NONE,		false },
+	{ "on",			SPECTRE_V2_USER_CMD_FORCE,		true  },
+	{ "prctl",		SPECTRE_V2_USER_CMD_PRCTL,		false },
+	{ "prctl,ibpb",		SPECTRE_V2_USER_CMD_PRCTL_IBPB,		false },
+	{ "seccomp",		SPECTRE_V2_USER_CMD_SECCOMP,		false },
+	{ "seccomp,ibpb",	SPECTRE_V2_USER_CMD_SECCOMP_IBPB,	false },
+};
+
+static void __init spec_v2_user_print_cond(const char *reason, bool secure)
+{
+	if (boot_cpu_has_bug(X86_BUG_SPECTRE_V2) != secure)
+		pr_info("spectre_v2_user=%s forced on command line.\n", reason);
+}
+
+static __ro_after_init enum spectre_v2_mitigation_cmd spectre_v2_cmd;
+
+static enum spectre_v2_user_cmd __init
+spectre_v2_parse_user_cmdline(void)
+{
+	char arg[20];
+	int ret, i;
+
+	switch (spectre_v2_cmd) {
+	case SPECTRE_V2_CMD_NONE:
+		return SPECTRE_V2_USER_CMD_NONE;
+	case SPECTRE_V2_CMD_FORCE:
+		return SPECTRE_V2_USER_CMD_FORCE;
+	default:
+		break;
+	}
+
+	ret = cmdline_find_option(boot_command_line, "spectre_v2_user",
+				  arg, sizeof(arg));
+	if (ret < 0)
+		return SPECTRE_V2_USER_CMD_AUTO;
+
+	for (i = 0; i < ARRAY_SIZE(v2_user_options); i++) {
+		if (match_option(arg, ret, v2_user_options[i].option)) {
+			spec_v2_user_print_cond(v2_user_options[i].option,
+						v2_user_options[i].secure);
+			return v2_user_options[i].cmd;
+		}
+	}
+
+	pr_err("Unknown user space protection option (%s). Switching to AUTO select\n", arg);
+	return SPECTRE_V2_USER_CMD_AUTO;
+}
+
+static inline bool spectre_v2_in_ibrs_mode(enum spectre_v2_mitigation mode)
+{
+	return spectre_v2_in_eibrs_mode(mode) || mode == SPECTRE_V2_IBRS;
+}
+
+static void __init
+spectre_v2_user_select_mitigation(void)
+{
+	enum spectre_v2_user_mitigation mode = SPECTRE_V2_USER_NONE;
+	bool smt_possible = IS_ENABLED(CONFIG_SMP);
+	enum spectre_v2_user_cmd cmd;
+
+	if (!boot_cpu_has(X86_FEATURE_IBPB) && !boot_cpu_has(X86_FEATURE_STIBP))
+		return;
+
+	if (cpu_smt_control == CPU_SMT_FORCE_DISABLED ||
+	    cpu_smt_control == CPU_SMT_NOT_SUPPORTED)
+		smt_possible = false;
+
+	cmd = spectre_v2_parse_user_cmdline();
+	switch (cmd) {
+	case SPECTRE_V2_USER_CMD_NONE:
+		goto set_mode;
+	case SPECTRE_V2_USER_CMD_FORCE:
+		mode = SPECTRE_V2_USER_STRICT;
+		break;
+	case SPECTRE_V2_USER_CMD_AUTO:
+	case SPECTRE_V2_USER_CMD_PRCTL:
+	case SPECTRE_V2_USER_CMD_PRCTL_IBPB:
+		mode = SPECTRE_V2_USER_PRCTL;
+		break;
+	case SPECTRE_V2_USER_CMD_SECCOMP:
+	case SPECTRE_V2_USER_CMD_SECCOMP_IBPB:
+		if (IS_ENABLED(CONFIG_SECCOMP))
+			mode = SPECTRE_V2_USER_SECCOMP;
+		else
+			mode = SPECTRE_V2_USER_PRCTL;
+		break;
+	}
+
+	/* Initialize Indirect Branch Prediction Barrier */
+	if (boot_cpu_has(X86_FEATURE_IBPB)) {
+		setup_force_cpu_cap(X86_FEATURE_USE_IBPB);
+
+		spectre_v2_user_ibpb = mode;
+		switch (cmd) {
+		case SPECTRE_V2_USER_CMD_FORCE:
+		case SPECTRE_V2_USER_CMD_PRCTL_IBPB:
+		case SPECTRE_V2_USER_CMD_SECCOMP_IBPB:
+			static_branch_enable(&switch_mm_always_ibpb);
+			spectre_v2_user_ibpb = SPECTRE_V2_USER_STRICT;
+			break;
+		case SPECTRE_V2_USER_CMD_PRCTL:
+		case SPECTRE_V2_USER_CMD_AUTO:
+		case SPECTRE_V2_USER_CMD_SECCOMP:
+			static_branch_enable(&switch_mm_cond_ibpb);
+			break;
+		default:
+			break;
+		}
+
+		pr_info("mitigation: Enabling %s Indirect Branch Prediction Barrier\n",
+			static_key_enabled(&switch_mm_always_ibpb) ?
+			"always-on" : "conditional");
+	}
+
+	/*
+	 * If no STIBP, Intel enhanced IBRS is enabled, or SMT impossible, STIBP
+	 * is not required.
+	 *
+	 * Intel's Enhanced IBRS also protects against cross-thread branch target
+	 * injection in user-mode as the IBRS bit remains always set which
+	 * implicitly enables cross-thread protections.  However, in legacy IBRS
+	 * mode, the IBRS bit is set only on kernel entry and cleared on return
+	 * to userspace.  AMD Automatic IBRS also does not protect userspace.
+	 * These modes therefore disable the implicit cross-thread protection,
+	 * so allow for STIBP to be selected in those cases.
+	 */
+	if (!boot_cpu_has(X86_FEATURE_STIBP) ||
+	    !smt_possible ||
+	    (spectre_v2_in_eibrs_mode(spectre_v2_enabled) &&
+	     !boot_cpu_has(X86_FEATURE_AUTOIBRS)))
+		return;
+
+	/*
+	 * At this point, an STIBP mode other than "off" has been set.
+	 * If STIBP support is not being forced, check if STIBP always-on
+	 * is preferred.
+	 */
+	if (mode != SPECTRE_V2_USER_STRICT &&
+	    boot_cpu_has(X86_FEATURE_AMD_STIBP_ALWAYS_ON))
+		mode = SPECTRE_V2_USER_STRICT_PREFERRED;
+
+	if (retbleed_mitigation == RETBLEED_MITIGATION_UNRET ||
+	    retbleed_mitigation == RETBLEED_MITIGATION_IBPB) {
+		if (mode != SPECTRE_V2_USER_STRICT &&
+		    mode != SPECTRE_V2_USER_STRICT_PREFERRED)
+			pr_info("Selecting STIBP always-on mode to complement retbleed mitigation\n");
+		mode = SPECTRE_V2_USER_STRICT_PREFERRED;
+	}
+
+	spectre_v2_user_stibp = mode;
+
+set_mode:
+	pr_info("%s\n", spectre_v2_user_strings[mode]);
+}
+
+static const char * const spectre_v2_strings[] = {
+	[SPECTRE_V2_NONE]			= "Vulnerable",
+	[SPECTRE_V2_RETPOLINE]			= "Mitigation: Retpolines",
+	[SPECTRE_V2_LFENCE]			= "Mitigation: LFENCE",
+	[SPECTRE_V2_EIBRS]			= "Mitigation: Enhanced / Automatic IBRS",
+	[SPECTRE_V2_EIBRS_LFENCE]		= "Mitigation: Enhanced / Automatic IBRS + LFENCE",
+	[SPECTRE_V2_EIBRS_RETPOLINE]		= "Mitigation: Enhanced / Automatic IBRS + Retpolines",
+	[SPECTRE_V2_IBRS]			= "Mitigation: IBRS",
+};
+
+static const struct {
+	const char *option;
+	enum spectre_v2_mitigation_cmd cmd;
+	bool secure;
+} mitigation_options[] __initconst = {
+	{ "off",		SPECTRE_V2_CMD_NONE,		  false },
+	{ "on",			SPECTRE_V2_CMD_FORCE,		  true  },
+	{ "retpoline",		SPECTRE_V2_CMD_RETPOLINE,	  false },
+	{ "retpoline,amd",	SPECTRE_V2_CMD_RETPOLINE_LFENCE,  false },
+	{ "retpoline,lfence",	SPECTRE_V2_CMD_RETPOLINE_LFENCE,  false },
+	{ "retpoline,generic",	SPECTRE_V2_CMD_RETPOLINE_GENERIC, false },
+	{ "eibrs",		SPECTRE_V2_CMD_EIBRS,		  false },
+	{ "eibrs,lfence",	SPECTRE_V2_CMD_EIBRS_LFENCE,	  false },
+	{ "eibrs,retpoline",	SPECTRE_V2_CMD_EIBRS_RETPOLINE,	  false },
+	{ "auto",		SPECTRE_V2_CMD_AUTO,		  false },
+	{ "ibrs",		SPECTRE_V2_CMD_IBRS,              false },
+};
+
+static void __init spec_v2_print_cond(const char *reason, bool secure)
+{
+	if (boot_cpu_has_bug(X86_BUG_SPECTRE_V2) != secure)
+		pr_info("%s selected on command line.\n", reason);
+}
+
+static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void)
+{
+	enum spectre_v2_mitigation_cmd cmd = SPECTRE_V2_CMD_AUTO;
+	char arg[20];
+	int ret, i;
+
+	if (cmdline_find_option_bool(boot_command_line, "nospectre_v2") ||
+	    cpu_mitigations_off())
+		return SPECTRE_V2_CMD_NONE;
+
+	ret = cmdline_find_option(boot_command_line, "spectre_v2", arg, sizeof(arg));
+	if (ret < 0)
+		return SPECTRE_V2_CMD_AUTO;
+
+	for (i = 0; i < ARRAY_SIZE(mitigation_options); i++) {
+		if (!match_option(arg, ret, mitigation_options[i].option))
+			continue;
+		cmd = mitigation_options[i].cmd;
+		break;
+	}
+
+	if (i >= ARRAY_SIZE(mitigation_options)) {
+		pr_err("unknown option (%s). Switching to AUTO select\n", arg);
+		return SPECTRE_V2_CMD_AUTO;
+	}
+
+	if ((cmd == SPECTRE_V2_CMD_RETPOLINE ||
+	     cmd == SPECTRE_V2_CMD_RETPOLINE_LFENCE ||
+	     cmd == SPECTRE_V2_CMD_RETPOLINE_GENERIC ||
+	     cmd == SPECTRE_V2_CMD_EIBRS_LFENCE ||
+	     cmd == SPECTRE_V2_CMD_EIBRS_RETPOLINE) &&
+	    !IS_ENABLED(CONFIG_RETPOLINE)) {
+		pr_err("%s selected but not compiled in. Switching to AUTO select\n",
+		       mitigation_options[i].option);
+		return SPECTRE_V2_CMD_AUTO;
+	}
+
+	if ((cmd == SPECTRE_V2_CMD_EIBRS ||
+	     cmd == SPECTRE_V2_CMD_EIBRS_LFENCE ||
+	     cmd == SPECTRE_V2_CMD_EIBRS_RETPOLINE) &&
+	    !boot_cpu_has(X86_FEATURE_IBRS_ENHANCED)) {
+		pr_err("%s selected but CPU doesn't have Enhanced or Automatic IBRS. Switching to AUTO select\n",
+		       mitigation_options[i].option);
+		return SPECTRE_V2_CMD_AUTO;
+	}
+
+	if ((cmd == SPECTRE_V2_CMD_RETPOLINE_LFENCE ||
+	     cmd == SPECTRE_V2_CMD_EIBRS_LFENCE) &&
+	    !boot_cpu_has(X86_FEATURE_LFENCE_RDTSC)) {
+		pr_err("%s selected, but CPU doesn't have a serializing LFENCE. Switching to AUTO select\n",
+		       mitigation_options[i].option);
+		return SPECTRE_V2_CMD_AUTO;
+	}
+
+	if (cmd == SPECTRE_V2_CMD_IBRS && !IS_ENABLED(CONFIG_CPU_IBRS_ENTRY)) {
+		pr_err("%s selected but not compiled in. Switching to AUTO select\n",
+		       mitigation_options[i].option);
+		return SPECTRE_V2_CMD_AUTO;
+	}
+
+	if (cmd == SPECTRE_V2_CMD_IBRS && boot_cpu_data.x86_vendor != X86_VENDOR_INTEL) {
+		pr_err("%s selected but not Intel CPU. Switching to AUTO select\n",
+		       mitigation_options[i].option);
+		return SPECTRE_V2_CMD_AUTO;
+	}
+
+	if (cmd == SPECTRE_V2_CMD_IBRS && !boot_cpu_has(X86_FEATURE_IBRS)) {
+		pr_err("%s selected but CPU doesn't have IBRS. Switching to AUTO select\n",
+		       mitigation_options[i].option);
+		return SPECTRE_V2_CMD_AUTO;
+	}
+
+	if (cmd == SPECTRE_V2_CMD_IBRS && cpu_feature_enabled(X86_FEATURE_XENPV)) {
+		pr_err("%s selected but running as XenPV guest. Switching to AUTO select\n",
+		       mitigation_options[i].option);
+		return SPECTRE_V2_CMD_AUTO;
+	}
+
+	spec_v2_print_cond(mitigation_options[i].option,
+			   mitigation_options[i].secure);
+	return cmd;
+}
+
+static enum spectre_v2_mitigation __init spectre_v2_select_retpoline(void)
+{
+	if (!IS_ENABLED(CONFIG_RETPOLINE)) {
+		pr_err("Kernel not compiled with retpoline; no mitigation available!");
+		return SPECTRE_V2_NONE;
+	}
+
+	return SPECTRE_V2_RETPOLINE;
+}
+
+/* Disable in-kernel use of non-RSB RET predictors */
+static void __init spec_ctrl_disable_kernel_rrsba(void)
+{
+	u64 ia32_cap;
+
+	if (!boot_cpu_has(X86_FEATURE_RRSBA_CTRL))
+		return;
+
+	ia32_cap = x86_read_arch_cap_msr();
+
+	if (ia32_cap & ARCH_CAP_RRSBA) {
+		x86_spec_ctrl_base |= SPEC_CTRL_RRSBA_DIS_S;
+		update_spec_ctrl(x86_spec_ctrl_base);
+	}
+}
+
+static void __init spectre_v2_determine_rsb_fill_type_at_vmexit(enum spectre_v2_mitigation mode)
+{
+	/*
+	 * Similar to context switches, there are two types of RSB attacks
+	 * after VM exit:
+	 *
+	 * 1) RSB underflow
+	 *
+	 * 2) Poisoned RSB entry
+	 *
+	 * When retpoline is enabled, both are mitigated by filling/clearing
+	 * the RSB.
+	 *
+	 * When IBRS is enabled, while #1 would be mitigated by the IBRS branch
+	 * prediction isolation protections, RSB still needs to be cleared
+	 * because of #2.  Note that SMEP provides no protection here, unlike
+	 * user-space-poisoned RSB entries.
+	 *
+	 * eIBRS should protect against RSB poisoning, but if the EIBRS_PBRSB
+	 * bug is present then a LITE version of RSB protection is required,
+	 * just a single call needs to retire before a RET is executed.
+	 */
+	switch (mode) {
+	case SPECTRE_V2_NONE:
+		return;
+
+	case SPECTRE_V2_EIBRS_LFENCE:
+	case SPECTRE_V2_EIBRS:
+		if (boot_cpu_has_bug(X86_BUG_EIBRS_PBRSB)) {
+			setup_force_cpu_cap(X86_FEATURE_RSB_VMEXIT_LITE);
+			pr_info("Spectre v2 / PBRSB-eIBRS: Retire a single CALL on VMEXIT\n");
+		}
+		return;
+
+	case SPECTRE_V2_EIBRS_RETPOLINE:
+	case SPECTRE_V2_RETPOLINE:
+	case SPECTRE_V2_LFENCE:
+	case SPECTRE_V2_IBRS:
+		setup_force_cpu_cap(X86_FEATURE_RSB_VMEXIT);
+		pr_info("Spectre v2 / SpectreRSB : Filling RSB on VMEXIT\n");
+		return;
+	}
+
+	pr_warn_once("Unknown Spectre v2 mode, disabling RSB mitigation at VM exit");
+	dump_stack();
+}
+
+static void __init spectre_v2_select_mitigation(void)
+{
+	enum spectre_v2_mitigation_cmd cmd = spectre_v2_parse_cmdline();
+	enum spectre_v2_mitigation mode = SPECTRE_V2_NONE;
+
+	/*
+	 * If the CPU is not affected and the command line mode is NONE or AUTO
+	 * then nothing to do.
+	 */
+	if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2) &&
+	    (cmd == SPECTRE_V2_CMD_NONE || cmd == SPECTRE_V2_CMD_AUTO))
+		return;
+
+	switch (cmd) {
+	case SPECTRE_V2_CMD_NONE:
+		return;
+
+	case SPECTRE_V2_CMD_FORCE:
+	case SPECTRE_V2_CMD_AUTO:
+		if (boot_cpu_has(X86_FEATURE_IBRS_ENHANCED)) {
+			mode = SPECTRE_V2_EIBRS;
+			break;
+		}
+
+		if (IS_ENABLED(CONFIG_CPU_IBRS_ENTRY) &&
+		    boot_cpu_has_bug(X86_BUG_RETBLEED) &&
+		    retbleed_cmd != RETBLEED_CMD_OFF &&
+		    retbleed_cmd != RETBLEED_CMD_STUFF &&
+		    boot_cpu_has(X86_FEATURE_IBRS) &&
+		    boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) {
+			mode = SPECTRE_V2_IBRS;
+			break;
+		}
+
+		mode = spectre_v2_select_retpoline();
+		break;
+
+	case SPECTRE_V2_CMD_RETPOLINE_LFENCE:
+		pr_err(SPECTRE_V2_LFENCE_MSG);
+		mode = SPECTRE_V2_LFENCE;
+		break;
+
+	case SPECTRE_V2_CMD_RETPOLINE_GENERIC:
+		mode = SPECTRE_V2_RETPOLINE;
+		break;
+
+	case SPECTRE_V2_CMD_RETPOLINE:
+		mode = spectre_v2_select_retpoline();
+		break;
+
+	case SPECTRE_V2_CMD_IBRS:
+		mode = SPECTRE_V2_IBRS;
+		break;
+
+	case SPECTRE_V2_CMD_EIBRS:
+		mode = SPECTRE_V2_EIBRS;
+		break;
+
+	case SPECTRE_V2_CMD_EIBRS_LFENCE:
+		mode = SPECTRE_V2_EIBRS_LFENCE;
+		break;
+
+	case SPECTRE_V2_CMD_EIBRS_RETPOLINE:
+		mode = SPECTRE_V2_EIBRS_RETPOLINE;
+		break;
+	}
+
+	if (mode == SPECTRE_V2_EIBRS && unprivileged_ebpf_enabled())
+		pr_err(SPECTRE_V2_EIBRS_EBPF_MSG);
+
+	if (spectre_v2_in_ibrs_mode(mode)) {
+		if (boot_cpu_has(X86_FEATURE_AUTOIBRS)) {
+			msr_set_bit(MSR_EFER, _EFER_AUTOIBRS);
+		} else {
+			x86_spec_ctrl_base |= SPEC_CTRL_IBRS;
+			update_spec_ctrl(x86_spec_ctrl_base);
+		}
+	}
+
+	switch (mode) {
+	case SPECTRE_V2_NONE:
+	case SPECTRE_V2_EIBRS:
+		break;
+
+	case SPECTRE_V2_IBRS:
+		setup_force_cpu_cap(X86_FEATURE_KERNEL_IBRS);
+		if (boot_cpu_has(X86_FEATURE_IBRS_ENHANCED))
+			pr_warn(SPECTRE_V2_IBRS_PERF_MSG);
+		break;
+
+	case SPECTRE_V2_LFENCE:
+	case SPECTRE_V2_EIBRS_LFENCE:
+		setup_force_cpu_cap(X86_FEATURE_RETPOLINE_LFENCE);
+		fallthrough;
+
+	case SPECTRE_V2_RETPOLINE:
+	case SPECTRE_V2_EIBRS_RETPOLINE:
+		setup_force_cpu_cap(X86_FEATURE_RETPOLINE);
+		break;
+	}
+
+	/*
+	 * Disable alternate RSB predictions in kernel when indirect CALLs and
+	 * JMPs gets protection against BHI and Intramode-BTI, but RET
+	 * prediction from a non-RSB predictor is still a risk.
+	 */
+	if (mode == SPECTRE_V2_EIBRS_LFENCE ||
+	    mode == SPECTRE_V2_EIBRS_RETPOLINE ||
+	    mode == SPECTRE_V2_RETPOLINE)
+		spec_ctrl_disable_kernel_rrsba();
+
+	spectre_v2_enabled = mode;
+	pr_info("%s\n", spectre_v2_strings[mode]);
+
+	/*
+	 * If Spectre v2 protection has been enabled, fill the RSB during a
+	 * context switch.  In general there are two types of RSB attacks
+	 * across context switches, for which the CALLs/RETs may be unbalanced.
+	 *
+	 * 1) RSB underflow
+	 *
+	 *    Some Intel parts have "bottomless RSB".  When the RSB is empty,
+	 *    speculated return targets may come from the branch predictor,
+	 *    which could have a user-poisoned BTB or BHB entry.
+	 *
+	 *    AMD has it even worse: *all* returns are speculated from the BTB,
+	 *    regardless of the state of the RSB.
+	 *
+	 *    When IBRS or eIBRS is enabled, the "user -> kernel" attack
+	 *    scenario is mitigated by the IBRS branch prediction isolation
+	 *    properties, so the RSB buffer filling wouldn't be necessary to
+	 *    protect against this type of attack.
+	 *
+	 *    The "user -> user" attack scenario is mitigated by RSB filling.
+	 *
+	 * 2) Poisoned RSB entry
+	 *
+	 *    If the 'next' in-kernel return stack is shorter than 'prev',
+	 *    'next' could be tricked into speculating with a user-poisoned RSB
+	 *    entry.
+	 *
+	 *    The "user -> kernel" attack scenario is mitigated by SMEP and
+	 *    eIBRS.
+	 *
+	 *    The "user -> user" scenario, also known as SpectreBHB, requires
+	 *    RSB clearing.
+	 *
+	 * So to mitigate all cases, unconditionally fill RSB on context
+	 * switches.
+	 *
+	 * FIXME: Is this pointless for retbleed-affected AMD?
+	 */
+	setup_force_cpu_cap(X86_FEATURE_RSB_CTXSW);
+	pr_info("Spectre v2 / SpectreRSB mitigation: Filling RSB on context switch\n");
+
+	spectre_v2_determine_rsb_fill_type_at_vmexit(mode);
+
+	/*
+	 * Retpoline protects the kernel, but doesn't protect firmware.  IBRS
+	 * and Enhanced IBRS protect firmware too, so enable IBRS around
+	 * firmware calls only when IBRS / Enhanced / Automatic IBRS aren't
+	 * otherwise enabled.
+	 *
+	 * Use "mode" to check Enhanced IBRS instead of boot_cpu_has(), because
+	 * the user might select retpoline on the kernel command line and if
+	 * the CPU supports Enhanced IBRS, kernel might un-intentionally not
+	 * enable IBRS around firmware calls.
+	 */
+	if (boot_cpu_has_bug(X86_BUG_RETBLEED) &&
+	    boot_cpu_has(X86_FEATURE_IBPB) &&
+	    (boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
+	     boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)) {
+
+		if (retbleed_cmd != RETBLEED_CMD_IBPB) {
+			setup_force_cpu_cap(X86_FEATURE_USE_IBPB_FW);
+			pr_info("Enabling Speculation Barrier for firmware calls\n");
+		}
+
+	} else if (boot_cpu_has(X86_FEATURE_IBRS) && !spectre_v2_in_ibrs_mode(mode)) {
+		setup_force_cpu_cap(X86_FEATURE_USE_IBRS_FW);
+		pr_info("Enabling Restricted Speculation for firmware calls\n");
+	}
+
+	/* Set up IBPB and STIBP depending on the general spectre V2 command */
+	spectre_v2_cmd = cmd;
+}
+
+static void update_stibp_msr(void * __unused)
+{
+	u64 val = spec_ctrl_current() | (x86_spec_ctrl_base & SPEC_CTRL_STIBP);
+	update_spec_ctrl(val);
+}
+
+/* Update x86_spec_ctrl_base in case SMT state changed. */
+static void update_stibp_strict(void)
+{
+	u64 mask = x86_spec_ctrl_base & ~SPEC_CTRL_STIBP;
+
+	if (sched_smt_active())
+		mask |= SPEC_CTRL_STIBP;
+
+	if (mask == x86_spec_ctrl_base)
+		return;
+
+	pr_info("Update user space SMT mitigation: STIBP %s\n",
+		mask & SPEC_CTRL_STIBP ? "always-on" : "off");
+	x86_spec_ctrl_base = mask;
+	on_each_cpu(update_stibp_msr, NULL, 1);
+}
+
+/* Update the static key controlling the evaluation of TIF_SPEC_IB */
+static void update_indir_branch_cond(void)
+{
+	if (sched_smt_active())
+		static_branch_enable(&switch_to_cond_stibp);
+	else
+		static_branch_disable(&switch_to_cond_stibp);
+}
+
+#undef pr_fmt
+#define pr_fmt(fmt) fmt
+
+/* Update the static key controlling the MDS CPU buffer clear in idle */
+static void update_mds_branch_idle(void)
+{
+	u64 ia32_cap = x86_read_arch_cap_msr();
+
+	/*
+	 * Enable the idle clearing if SMT is active on CPUs which are
+	 * affected only by MSBDS and not any other MDS variant.
+	 *
+	 * The other variants cannot be mitigated when SMT is enabled, so
+	 * clearing the buffers on idle just to prevent the Store Buffer
+	 * repartitioning leak would be a window dressing exercise.
+	 */
+	if (!boot_cpu_has_bug(X86_BUG_MSBDS_ONLY))
+		return;
+
+	if (sched_smt_active()) {
+		static_branch_enable(&mds_idle_clear);
+	} else if (mmio_mitigation == MMIO_MITIGATION_OFF ||
+		   (ia32_cap & ARCH_CAP_FBSDP_NO)) {
+		static_branch_disable(&mds_idle_clear);
+	}
+}
+
+#define MDS_MSG_SMT "MDS CPU bug present and SMT on, data leak possible. See https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/mds.html for more details.\n"
+#define TAA_MSG_SMT "TAA CPU bug present and SMT on, data leak possible. See https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/tsx_async_abort.html for more details.\n"
+#define MMIO_MSG_SMT "MMIO Stale Data CPU bug present and SMT on, data leak possible. See https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/processor_mmio_stale_data.html for more details.\n"
+
+void cpu_bugs_smt_update(void)
+{
+	mutex_lock(&spec_ctrl_mutex);
+
+	if (sched_smt_active() && unprivileged_ebpf_enabled() &&
+	    spectre_v2_enabled == SPECTRE_V2_EIBRS_LFENCE)
+		pr_warn_once(SPECTRE_V2_EIBRS_LFENCE_EBPF_SMT_MSG);
+
+	switch (spectre_v2_user_stibp) {
+	case SPECTRE_V2_USER_NONE:
+		break;
+	case SPECTRE_V2_USER_STRICT:
+	case SPECTRE_V2_USER_STRICT_PREFERRED:
+		update_stibp_strict();
+		break;
+	case SPECTRE_V2_USER_PRCTL:
+	case SPECTRE_V2_USER_SECCOMP:
+		update_indir_branch_cond();
+		break;
+	}
+
+	switch (mds_mitigation) {
+	case MDS_MITIGATION_FULL:
+	case MDS_MITIGATION_VMWERV:
+		if (sched_smt_active() && !boot_cpu_has(X86_BUG_MSBDS_ONLY))
+			pr_warn_once(MDS_MSG_SMT);
+		update_mds_branch_idle();
+		break;
+	case MDS_MITIGATION_OFF:
+		break;
+	}
+
+	switch (taa_mitigation) {
+	case TAA_MITIGATION_VERW:
+	case TAA_MITIGATION_UCODE_NEEDED:
+		if (sched_smt_active())
+			pr_warn_once(TAA_MSG_SMT);
+		break;
+	case TAA_MITIGATION_TSX_DISABLED:
+	case TAA_MITIGATION_OFF:
+		break;
+	}
+
+	switch (mmio_mitigation) {
+	case MMIO_MITIGATION_VERW:
+	case MMIO_MITIGATION_UCODE_NEEDED:
+		if (sched_smt_active())
+			pr_warn_once(MMIO_MSG_SMT);
+		break;
+	case MMIO_MITIGATION_OFF:
+		break;
+	}
+
+	mutex_unlock(&spec_ctrl_mutex);
+}
+
+#undef pr_fmt
+#define pr_fmt(fmt)	"Speculative Store Bypass: " fmt
+
+static enum ssb_mitigation ssb_mode __ro_after_init = SPEC_STORE_BYPASS_NONE;
+
+/* The kernel command line selection */
+enum ssb_mitigation_cmd {
+	SPEC_STORE_BYPASS_CMD_NONE,
+	SPEC_STORE_BYPASS_CMD_AUTO,
+	SPEC_STORE_BYPASS_CMD_ON,
+	SPEC_STORE_BYPASS_CMD_PRCTL,
+	SPEC_STORE_BYPASS_CMD_SECCOMP,
+};
+
+static const char * const ssb_strings[] = {
+	[SPEC_STORE_BYPASS_NONE]	= "Vulnerable",
+	[SPEC_STORE_BYPASS_DISABLE]	= "Mitigation: Speculative Store Bypass disabled",
+	[SPEC_STORE_BYPASS_PRCTL]	= "Mitigation: Speculative Store Bypass disabled via prctl",
+	[SPEC_STORE_BYPASS_SECCOMP]	= "Mitigation: Speculative Store Bypass disabled via prctl and seccomp",
+};
+
+static const struct {
+	const char *option;
+	enum ssb_mitigation_cmd cmd;
+} ssb_mitigation_options[]  __initconst = {
+	{ "auto",	SPEC_STORE_BYPASS_CMD_AUTO },    /* Platform decides */
+	{ "on",		SPEC_STORE_BYPASS_CMD_ON },      /* Disable Speculative Store Bypass */
+	{ "off",	SPEC_STORE_BYPASS_CMD_NONE },    /* Don't touch Speculative Store Bypass */
+	{ "prctl",	SPEC_STORE_BYPASS_CMD_PRCTL },   /* Disable Speculative Store Bypass via prctl */
+	{ "seccomp",	SPEC_STORE_BYPASS_CMD_SECCOMP }, /* Disable Speculative Store Bypass via prctl and seccomp */
+};
+
+static enum ssb_mitigation_cmd __init ssb_parse_cmdline(void)
+{
+	enum ssb_mitigation_cmd cmd = SPEC_STORE_BYPASS_CMD_AUTO;
+	char arg[20];
+	int ret, i;
+
+	if (cmdline_find_option_bool(boot_command_line, "nospec_store_bypass_disable") ||
+	    cpu_mitigations_off()) {
+		return SPEC_STORE_BYPASS_CMD_NONE;
+	} else {
+		ret = cmdline_find_option(boot_command_line, "spec_store_bypass_disable",
+					  arg, sizeof(arg));
+		if (ret < 0)
+			return SPEC_STORE_BYPASS_CMD_AUTO;
+
+		for (i = 0; i < ARRAY_SIZE(ssb_mitigation_options); i++) {
+			if (!match_option(arg, ret, ssb_mitigation_options[i].option))
+				continue;
+
+			cmd = ssb_mitigation_options[i].cmd;
+			break;
+		}
+
+		if (i >= ARRAY_SIZE(ssb_mitigation_options)) {
+			pr_err("unknown option (%s). Switching to AUTO select\n", arg);
+			return SPEC_STORE_BYPASS_CMD_AUTO;
+		}
+	}
+
+	return cmd;
+}
+
+static enum ssb_mitigation __init __ssb_select_mitigation(void)
+{
+	enum ssb_mitigation mode = SPEC_STORE_BYPASS_NONE;
+	enum ssb_mitigation_cmd cmd;
+
+	if (!boot_cpu_has(X86_FEATURE_SSBD))
+		return mode;
+
+	cmd = ssb_parse_cmdline();
+	if (!boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS) &&
+	    (cmd == SPEC_STORE_BYPASS_CMD_NONE ||
+	     cmd == SPEC_STORE_BYPASS_CMD_AUTO))
+		return mode;
+
+	switch (cmd) {
+	case SPEC_STORE_BYPASS_CMD_SECCOMP:
+		/*
+		 * Choose prctl+seccomp as the default mode if seccomp is
+		 * enabled.
+		 */
+		if (IS_ENABLED(CONFIG_SECCOMP))
+			mode = SPEC_STORE_BYPASS_SECCOMP;
+		else
+			mode = SPEC_STORE_BYPASS_PRCTL;
+		break;
+	case SPEC_STORE_BYPASS_CMD_ON:
+		mode = SPEC_STORE_BYPASS_DISABLE;
+		break;
+	case SPEC_STORE_BYPASS_CMD_AUTO:
+	case SPEC_STORE_BYPASS_CMD_PRCTL:
+		mode = SPEC_STORE_BYPASS_PRCTL;
+		break;
+	case SPEC_STORE_BYPASS_CMD_NONE:
+		break;
+	}
+
+	/*
+	 * We have three CPU feature flags that are in play here:
+	 *  - X86_BUG_SPEC_STORE_BYPASS - CPU is susceptible.
+	 *  - X86_FEATURE_SSBD - CPU is able to turn off speculative store bypass
+	 *  - X86_FEATURE_SPEC_STORE_BYPASS_DISABLE - engage the mitigation
+	 */
+	if (mode == SPEC_STORE_BYPASS_DISABLE) {
+		setup_force_cpu_cap(X86_FEATURE_SPEC_STORE_BYPASS_DISABLE);
+		/*
+		 * Intel uses the SPEC CTRL MSR Bit(2) for this, while AMD may
+		 * use a completely different MSR and bit dependent on family.
+		 */
+		if (!static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD) &&
+		    !static_cpu_has(X86_FEATURE_AMD_SSBD)) {
+			x86_amd_ssb_disable();
+		} else {
+			x86_spec_ctrl_base |= SPEC_CTRL_SSBD;
+			update_spec_ctrl(x86_spec_ctrl_base);
+		}
+	}
+
+	return mode;
+}
+
+static void ssb_select_mitigation(void)
+{
+	ssb_mode = __ssb_select_mitigation();
+
+	if (boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS))
+		pr_info("%s\n", ssb_strings[ssb_mode]);
+}
+
+#undef pr_fmt
+#define pr_fmt(fmt)     "Speculation prctl: " fmt
+
+static void task_update_spec_tif(struct task_struct *tsk)
+{
+	/* Force the update of the real TIF bits */
+	set_tsk_thread_flag(tsk, TIF_SPEC_FORCE_UPDATE);
+
+	/*
+	 * Immediately update the speculation control MSRs for the current
+	 * task, but for a non-current task delay setting the CPU
+	 * mitigation until it is scheduled next.
+	 *
+	 * This can only happen for SECCOMP mitigation. For PRCTL it's
+	 * always the current task.
+	 */
+	if (tsk == current)
+		speculation_ctrl_update_current();
+}
+
+static int l1d_flush_prctl_set(struct task_struct *task, unsigned long ctrl)
+{
+
+	if (!static_branch_unlikely(&switch_mm_cond_l1d_flush))
+		return -EPERM;
+
+	switch (ctrl) {
+	case PR_SPEC_ENABLE:
+		set_ti_thread_flag(&task->thread_info, TIF_SPEC_L1D_FLUSH);
+		return 0;
+	case PR_SPEC_DISABLE:
+		clear_ti_thread_flag(&task->thread_info, TIF_SPEC_L1D_FLUSH);
+		return 0;
+	default:
+		return -ERANGE;
+	}
+}
+
+static int ssb_prctl_set(struct task_struct *task, unsigned long ctrl)
+{
+	if (ssb_mode != SPEC_STORE_BYPASS_PRCTL &&
+	    ssb_mode != SPEC_STORE_BYPASS_SECCOMP)
+		return -ENXIO;
+
+	switch (ctrl) {
+	case PR_SPEC_ENABLE:
+		/* If speculation is force disabled, enable is not allowed */
+		if (task_spec_ssb_force_disable(task))
+			return -EPERM;
+		task_clear_spec_ssb_disable(task);
+		task_clear_spec_ssb_noexec(task);
+		task_update_spec_tif(task);
+		break;
+	case PR_SPEC_DISABLE:
+		task_set_spec_ssb_disable(task);
+		task_clear_spec_ssb_noexec(task);
+		task_update_spec_tif(task);
+		break;
+	case PR_SPEC_FORCE_DISABLE:
+		task_set_spec_ssb_disable(task);
+		task_set_spec_ssb_force_disable(task);
+		task_clear_spec_ssb_noexec(task);
+		task_update_spec_tif(task);
+		break;
+	case PR_SPEC_DISABLE_NOEXEC:
+		if (task_spec_ssb_force_disable(task))
+			return -EPERM;
+		task_set_spec_ssb_disable(task);
+		task_set_spec_ssb_noexec(task);
+		task_update_spec_tif(task);
+		break;
+	default:
+		return -ERANGE;
+	}
+	return 0;
+}
+
+static bool is_spec_ib_user_controlled(void)
+{
+	return spectre_v2_user_ibpb == SPECTRE_V2_USER_PRCTL ||
+		spectre_v2_user_ibpb == SPECTRE_V2_USER_SECCOMP ||
+		spectre_v2_user_stibp == SPECTRE_V2_USER_PRCTL ||
+		spectre_v2_user_stibp == SPECTRE_V2_USER_SECCOMP;
+}
+
+static int ib_prctl_set(struct task_struct *task, unsigned long ctrl)
+{
+	switch (ctrl) {
+	case PR_SPEC_ENABLE:
+		if (spectre_v2_user_ibpb == SPECTRE_V2_USER_NONE &&
+		    spectre_v2_user_stibp == SPECTRE_V2_USER_NONE)
+			return 0;
+
+		/*
+		 * With strict mode for both IBPB and STIBP, the instruction
+		 * code paths avoid checking this task flag and instead,
+		 * unconditionally run the instruction. However, STIBP and IBPB
+		 * are independent and either can be set to conditionally
+		 * enabled regardless of the mode of the other.
+		 *
+		 * If either is set to conditional, allow the task flag to be
+		 * updated, unless it was force-disabled by a previous prctl
+		 * call. Currently, this is possible on an AMD CPU which has the
+		 * feature X86_FEATURE_AMD_STIBP_ALWAYS_ON. In this case, if the
+		 * kernel is booted with 'spectre_v2_user=seccomp', then
+		 * spectre_v2_user_ibpb == SPECTRE_V2_USER_SECCOMP and
+		 * spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT_PREFERRED.
+		 */
+		if (!is_spec_ib_user_controlled() ||
+		    task_spec_ib_force_disable(task))
+			return -EPERM;
+
+		task_clear_spec_ib_disable(task);
+		task_update_spec_tif(task);
+		break;
+	case PR_SPEC_DISABLE:
+	case PR_SPEC_FORCE_DISABLE:
+		/*
+		 * Indirect branch speculation is always allowed when
+		 * mitigation is force disabled.
+		 */
+		if (spectre_v2_user_ibpb == SPECTRE_V2_USER_NONE &&
+		    spectre_v2_user_stibp == SPECTRE_V2_USER_NONE)
+			return -EPERM;
+
+		if (!is_spec_ib_user_controlled())
+			return 0;
+
+		task_set_spec_ib_disable(task);
+		if (ctrl == PR_SPEC_FORCE_DISABLE)
+			task_set_spec_ib_force_disable(task);
+		task_update_spec_tif(task);
+		if (task == current)
+			indirect_branch_prediction_barrier();
+		break;
+	default:
+		return -ERANGE;
+	}
+	return 0;
+}
+
+int arch_prctl_spec_ctrl_set(struct task_struct *task, unsigned long which,
+			     unsigned long ctrl)
+{
+	switch (which) {
+	case PR_SPEC_STORE_BYPASS:
+		return ssb_prctl_set(task, ctrl);
+	case PR_SPEC_INDIRECT_BRANCH:
+		return ib_prctl_set(task, ctrl);
+	case PR_SPEC_L1D_FLUSH:
+		return l1d_flush_prctl_set(task, ctrl);
+	default:
+		return -ENODEV;
+	}
+}
+
+#ifdef CONFIG_SECCOMP
+void arch_seccomp_spec_mitigate(struct task_struct *task)
+{
+	if (ssb_mode == SPEC_STORE_BYPASS_SECCOMP)
+		ssb_prctl_set(task, PR_SPEC_FORCE_DISABLE);
+	if (spectre_v2_user_ibpb == SPECTRE_V2_USER_SECCOMP ||
+	    spectre_v2_user_stibp == SPECTRE_V2_USER_SECCOMP)
+		ib_prctl_set(task, PR_SPEC_FORCE_DISABLE);
+}
+#endif
+
+static int l1d_flush_prctl_get(struct task_struct *task)
+{
+	if (!static_branch_unlikely(&switch_mm_cond_l1d_flush))
+		return PR_SPEC_FORCE_DISABLE;
+
+	if (test_ti_thread_flag(&task->thread_info, TIF_SPEC_L1D_FLUSH))
+		return PR_SPEC_PRCTL | PR_SPEC_ENABLE;
+	else
+		return PR_SPEC_PRCTL | PR_SPEC_DISABLE;
+}
+
+static int ssb_prctl_get(struct task_struct *task)
+{
+	switch (ssb_mode) {
+	case SPEC_STORE_BYPASS_DISABLE:
+		return PR_SPEC_DISABLE;
+	case SPEC_STORE_BYPASS_SECCOMP:
+	case SPEC_STORE_BYPASS_PRCTL:
+		if (task_spec_ssb_force_disable(task))
+			return PR_SPEC_PRCTL | PR_SPEC_FORCE_DISABLE;
+		if (task_spec_ssb_noexec(task))
+			return PR_SPEC_PRCTL | PR_SPEC_DISABLE_NOEXEC;
+		if (task_spec_ssb_disable(task))
+			return PR_SPEC_PRCTL | PR_SPEC_DISABLE;
+		return PR_SPEC_PRCTL | PR_SPEC_ENABLE;
+	default:
+		if (boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS))
+			return PR_SPEC_ENABLE;
+		return PR_SPEC_NOT_AFFECTED;
+	}
+}
+
+static int ib_prctl_get(struct task_struct *task)
+{
+	if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
+		return PR_SPEC_NOT_AFFECTED;
+
+	if (spectre_v2_user_ibpb == SPECTRE_V2_USER_NONE &&
+	    spectre_v2_user_stibp == SPECTRE_V2_USER_NONE)
+		return PR_SPEC_ENABLE;
+	else if (is_spec_ib_user_controlled()) {
+		if (task_spec_ib_force_disable(task))
+			return PR_SPEC_PRCTL | PR_SPEC_FORCE_DISABLE;
+		if (task_spec_ib_disable(task))
+			return PR_SPEC_PRCTL | PR_SPEC_DISABLE;
+		return PR_SPEC_PRCTL | PR_SPEC_ENABLE;
+	} else if (spectre_v2_user_ibpb == SPECTRE_V2_USER_STRICT ||
+	    spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT ||
+	    spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT_PREFERRED)
+		return PR_SPEC_DISABLE;
+	else
+		return PR_SPEC_NOT_AFFECTED;
+}
+
+int arch_prctl_spec_ctrl_get(struct task_struct *task, unsigned long which)
+{
+	switch (which) {
+	case PR_SPEC_STORE_BYPASS:
+		return ssb_prctl_get(task);
+	case PR_SPEC_INDIRECT_BRANCH:
+		return ib_prctl_get(task);
+	case PR_SPEC_L1D_FLUSH:
+		return l1d_flush_prctl_get(task);
+	default:
+		return -ENODEV;
+	}
+}
+
+void x86_spec_ctrl_setup_ap(void)
+{
+	if (boot_cpu_has(X86_FEATURE_MSR_SPEC_CTRL))
+		update_spec_ctrl(x86_spec_ctrl_base);
+
+	if (ssb_mode == SPEC_STORE_BYPASS_DISABLE)
+		x86_amd_ssb_disable();
+}
+
+bool itlb_multihit_kvm_mitigation;
+EXPORT_SYMBOL_GPL(itlb_multihit_kvm_mitigation);
+
+#undef pr_fmt
+#define pr_fmt(fmt)	"L1TF: " fmt
+
+/* Default mitigation for L1TF-affected CPUs */
+enum l1tf_mitigations l1tf_mitigation __ro_after_init = L1TF_MITIGATION_FLUSH;
+#if IS_ENABLED(CONFIG_KVM_INTEL)
+EXPORT_SYMBOL_GPL(l1tf_mitigation);
+#endif
+enum vmx_l1d_flush_state l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_AUTO;
+EXPORT_SYMBOL_GPL(l1tf_vmx_mitigation);
+
+/*
+ * These CPUs all support 44bits physical address space internally in the
+ * cache but CPUID can report a smaller number of physical address bits.
+ *
+ * The L1TF mitigation uses the top most address bit for the inversion of
+ * non present PTEs. When the installed memory reaches into the top most
+ * address bit due to memory holes, which has been observed on machines
+ * which report 36bits physical address bits and have 32G RAM installed,
+ * then the mitigation range check in l1tf_select_mitigation() triggers.
+ * This is a false positive because the mitigation is still possible due to
+ * the fact that the cache uses 44bit internally. Use the cache bits
+ * instead of the reported physical bits and adjust them on the affected
+ * machines to 44bit if the reported bits are less than 44.
+ */
+static void override_cache_bits(struct cpuinfo_x86 *c)
+{
+	if (c->x86 != 6)
+		return;
+
+	switch (c->x86_model) {
+	case INTEL_FAM6_NEHALEM:
+	case INTEL_FAM6_WESTMERE:
+	case INTEL_FAM6_SANDYBRIDGE:
+	case INTEL_FAM6_IVYBRIDGE:
+	case INTEL_FAM6_HASWELL:
+	case INTEL_FAM6_HASWELL_L:
+	case INTEL_FAM6_HASWELL_G:
+	case INTEL_FAM6_BROADWELL:
+	case INTEL_FAM6_BROADWELL_G:
+	case INTEL_FAM6_SKYLAKE_L:
+	case INTEL_FAM6_SKYLAKE:
+	case INTEL_FAM6_KABYLAKE_L:
+	case INTEL_FAM6_KABYLAKE:
+		if (c->x86_cache_bits < 44)
+			c->x86_cache_bits = 44;
+		break;
+	}
+}
+
+static void __init l1tf_select_mitigation(void)
+{
+	u64 half_pa;
+
+	if (!boot_cpu_has_bug(X86_BUG_L1TF))
+		return;
+
+	if (cpu_mitigations_off())
+		l1tf_mitigation = L1TF_MITIGATION_OFF;
+	else if (cpu_mitigations_auto_nosmt())
+		l1tf_mitigation = L1TF_MITIGATION_FLUSH_NOSMT;
+
+	override_cache_bits(&boot_cpu_data);
+
+	switch (l1tf_mitigation) {
+	case L1TF_MITIGATION_OFF:
+	case L1TF_MITIGATION_FLUSH_NOWARN:
+	case L1TF_MITIGATION_FLUSH:
+		break;
+	case L1TF_MITIGATION_FLUSH_NOSMT:
+	case L1TF_MITIGATION_FULL:
+		cpu_smt_disable(false);
+		break;
+	case L1TF_MITIGATION_FULL_FORCE:
+		cpu_smt_disable(true);
+		break;
+	}
+
+#if CONFIG_PGTABLE_LEVELS == 2
+	pr_warn("Kernel not compiled for PAE. No mitigation for L1TF\n");
+	return;
+#endif
+
+	half_pa = (u64)l1tf_pfn_limit() << PAGE_SHIFT;
+	if (l1tf_mitigation != L1TF_MITIGATION_OFF &&
+			e820__mapped_any(half_pa, ULLONG_MAX - half_pa, E820_TYPE_RAM)) {
+		pr_warn("System has more than MAX_PA/2 memory. L1TF mitigation not effective.\n");
+		pr_info("You may make it effective by booting the kernel with mem=%llu parameter.\n",
+				half_pa);
+		pr_info("However, doing so will make a part of your RAM unusable.\n");
+		pr_info("Reading https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html might help you decide.\n");
+		return;
+	}
+
+	setup_force_cpu_cap(X86_FEATURE_L1TF_PTEINV);
+}
+
+static int __init l1tf_cmdline(char *str)
+{
+	if (!boot_cpu_has_bug(X86_BUG_L1TF))
+		return 0;
+
+	if (!str)
+		return -EINVAL;
+
+	if (!strcmp(str, "off"))
+		l1tf_mitigation = L1TF_MITIGATION_OFF;
+	else if (!strcmp(str, "flush,nowarn"))
+		l1tf_mitigation = L1TF_MITIGATION_FLUSH_NOWARN;
+	else if (!strcmp(str, "flush"))
+		l1tf_mitigation = L1TF_MITIGATION_FLUSH;
+	else if (!strcmp(str, "flush,nosmt"))
+		l1tf_mitigation = L1TF_MITIGATION_FLUSH_NOSMT;
+	else if (!strcmp(str, "full"))
+		l1tf_mitigation = L1TF_MITIGATION_FULL;
+	else if (!strcmp(str, "full,force"))
+		l1tf_mitigation = L1TF_MITIGATION_FULL_FORCE;
+
+	return 0;
+}
+early_param("l1tf", l1tf_cmdline);
+
+#undef pr_fmt
+#define pr_fmt(fmt)	"Speculative Return Stack Overflow: " fmt
+
+enum srso_mitigation {
+	SRSO_MITIGATION_NONE,
+	SRSO_MITIGATION_UCODE_NEEDED,
+	SRSO_MITIGATION_SAFE_RET_UCODE_NEEDED,
+	SRSO_MITIGATION_MICROCODE,
+	SRSO_MITIGATION_SAFE_RET,
+	SRSO_MITIGATION_IBPB,
+	SRSO_MITIGATION_IBPB_ON_VMEXIT,
+};
+
+enum srso_mitigation_cmd {
+	SRSO_CMD_OFF,
+	SRSO_CMD_MICROCODE,
+	SRSO_CMD_SAFE_RET,
+	SRSO_CMD_IBPB,
+	SRSO_CMD_IBPB_ON_VMEXIT,
+};
+
+static const char * const srso_strings[] = {
+	[SRSO_MITIGATION_NONE]			= "Vulnerable",
+	[SRSO_MITIGATION_UCODE_NEEDED]		= "Vulnerable: No microcode",
+	[SRSO_MITIGATION_SAFE_RET_UCODE_NEEDED]	= "Vulnerable: Safe RET, no microcode",
+	[SRSO_MITIGATION_MICROCODE]		= "Vulnerable: Microcode, no safe RET",
+	[SRSO_MITIGATION_SAFE_RET]		= "Mitigation: Safe RET",
+	[SRSO_MITIGATION_IBPB]			= "Mitigation: IBPB",
+	[SRSO_MITIGATION_IBPB_ON_VMEXIT]	= "Mitigation: IBPB on VMEXIT only"
+};
+
+static enum srso_mitigation srso_mitigation __ro_after_init = SRSO_MITIGATION_NONE;
+static enum srso_mitigation_cmd srso_cmd __ro_after_init = SRSO_CMD_SAFE_RET;
+
+static int __init srso_parse_cmdline(char *str)
+{
+	if (!str)
+		return -EINVAL;
+
+	if (!strcmp(str, "off"))
+		srso_cmd = SRSO_CMD_OFF;
+	else if (!strcmp(str, "microcode"))
+		srso_cmd = SRSO_CMD_MICROCODE;
+	else if (!strcmp(str, "safe-ret"))
+		srso_cmd = SRSO_CMD_SAFE_RET;
+	else if (!strcmp(str, "ibpb"))
+		srso_cmd = SRSO_CMD_IBPB;
+	else if (!strcmp(str, "ibpb-vmexit"))
+		srso_cmd = SRSO_CMD_IBPB_ON_VMEXIT;
+	else
+		pr_err("Ignoring unknown SRSO option (%s).", str);
+
+	return 0;
+}
+early_param("spec_rstack_overflow", srso_parse_cmdline);
+
+#define SRSO_NOTICE "WARNING: See https://kernel.org/doc/html/latest/admin-guide/hw-vuln/srso.html for mitigation options."
+
+static void __init srso_select_mitigation(void)
+{
+	bool has_microcode = boot_cpu_has(X86_FEATURE_IBPB_BRTYPE);
+
+	if (!boot_cpu_has_bug(X86_BUG_SRSO) || cpu_mitigations_off())
+		goto pred_cmd;
+
+	if (has_microcode) {
+		/*
+		 * Zen1/2 with SMT off aren't vulnerable after the right
+		 * IBPB microcode has been applied.
+		 */
+		if (boot_cpu_data.x86 < 0x19 && !cpu_smt_possible()) {
+			setup_force_cpu_cap(X86_FEATURE_SRSO_NO);
+			return;
+		}
+
+		if (retbleed_mitigation == RETBLEED_MITIGATION_IBPB) {
+			srso_mitigation = SRSO_MITIGATION_IBPB;
+			goto out;
+		}
+	} else {
+		pr_warn("IBPB-extending microcode not applied!\n");
+		pr_warn(SRSO_NOTICE);
+
+		/* may be overwritten by SRSO_CMD_SAFE_RET below */
+		srso_mitigation = SRSO_MITIGATION_UCODE_NEEDED;
+	}
+
+	switch (srso_cmd) {
+	case SRSO_CMD_OFF:
+		goto pred_cmd;
+
+	case SRSO_CMD_MICROCODE:
+		if (has_microcode) {
+			srso_mitigation = SRSO_MITIGATION_MICROCODE;
+			pr_warn(SRSO_NOTICE);
+		}
+		break;
+
+	case SRSO_CMD_SAFE_RET:
+		if (IS_ENABLED(CONFIG_CPU_SRSO)) {
+			/*
+			 * Enable the return thunk for generated code
+			 * like ftrace, static_call, etc.
+			 */
+			setup_force_cpu_cap(X86_FEATURE_RETHUNK);
+			setup_force_cpu_cap(X86_FEATURE_UNRET);
+
+			if (boot_cpu_data.x86 == 0x19) {
+				setup_force_cpu_cap(X86_FEATURE_SRSO_ALIAS);
+				x86_return_thunk = srso_alias_return_thunk;
+			} else {
+				setup_force_cpu_cap(X86_FEATURE_SRSO);
+				x86_return_thunk = srso_return_thunk;
+			}
+			if (has_microcode)
+				srso_mitigation = SRSO_MITIGATION_SAFE_RET;
+			else
+				srso_mitigation = SRSO_MITIGATION_SAFE_RET_UCODE_NEEDED;
+		} else {
+			pr_err("WARNING: kernel not compiled with CPU_SRSO.\n");
+			goto pred_cmd;
+		}
+		break;
+
+	case SRSO_CMD_IBPB:
+		if (IS_ENABLED(CONFIG_CPU_IBPB_ENTRY)) {
+			if (has_microcode) {
+				setup_force_cpu_cap(X86_FEATURE_ENTRY_IBPB);
+				srso_mitigation = SRSO_MITIGATION_IBPB;
+			}
+		} else {
+			pr_err("WARNING: kernel not compiled with CPU_IBPB_ENTRY.\n");
+			goto pred_cmd;
+		}
+		break;
+
+	case SRSO_CMD_IBPB_ON_VMEXIT:
+		if (IS_ENABLED(CONFIG_CPU_SRSO)) {
+			if (!boot_cpu_has(X86_FEATURE_ENTRY_IBPB) && has_microcode) {
+				setup_force_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT);
+				srso_mitigation = SRSO_MITIGATION_IBPB_ON_VMEXIT;
+			}
+		} else {
+			pr_err("WARNING: kernel not compiled with CPU_SRSO.\n");
+			goto pred_cmd;
+                }
+		break;
+
+	default:
+		break;
+	}
+
+out:
+	pr_info("%s\n", srso_strings[srso_mitigation]);
+
+pred_cmd:
+	if ((!boot_cpu_has_bug(X86_BUG_SRSO) || srso_cmd == SRSO_CMD_OFF) &&
+	     boot_cpu_has(X86_FEATURE_SBPB))
+		x86_pred_cmd = PRED_CMD_SBPB;
+}
+
+#undef pr_fmt
+#define pr_fmt(fmt) fmt
+
+#ifdef CONFIG_SYSFS
+
+#define L1TF_DEFAULT_MSG "Mitigation: PTE Inversion"
+
+#if IS_ENABLED(CONFIG_KVM_INTEL)
+static const char * const l1tf_vmx_states[] = {
+	[VMENTER_L1D_FLUSH_AUTO]		= "auto",
+	[VMENTER_L1D_FLUSH_NEVER]		= "vulnerable",
+	[VMENTER_L1D_FLUSH_COND]		= "conditional cache flushes",
+	[VMENTER_L1D_FLUSH_ALWAYS]		= "cache flushes",
+	[VMENTER_L1D_FLUSH_EPT_DISABLED]	= "EPT disabled",
+	[VMENTER_L1D_FLUSH_NOT_REQUIRED]	= "flush not necessary"
+};
+
+static ssize_t l1tf_show_state(char *buf)
+{
+	if (l1tf_vmx_mitigation == VMENTER_L1D_FLUSH_AUTO)
+		return sysfs_emit(buf, "%s\n", L1TF_DEFAULT_MSG);
+
+	if (l1tf_vmx_mitigation == VMENTER_L1D_FLUSH_EPT_DISABLED ||
+	    (l1tf_vmx_mitigation == VMENTER_L1D_FLUSH_NEVER &&
+	     sched_smt_active())) {
+		return sysfs_emit(buf, "%s; VMX: %s\n", L1TF_DEFAULT_MSG,
+				  l1tf_vmx_states[l1tf_vmx_mitigation]);
+	}
+
+	return sysfs_emit(buf, "%s; VMX: %s, SMT %s\n", L1TF_DEFAULT_MSG,
+			  l1tf_vmx_states[l1tf_vmx_mitigation],
+			  sched_smt_active() ? "vulnerable" : "disabled");
+}
+
+static ssize_t itlb_multihit_show_state(char *buf)
+{
+	if (!boot_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
+	    !boot_cpu_has(X86_FEATURE_VMX))
+		return sysfs_emit(buf, "KVM: Mitigation: VMX unsupported\n");
+	else if (!(cr4_read_shadow() & X86_CR4_VMXE))
+		return sysfs_emit(buf, "KVM: Mitigation: VMX disabled\n");
+	else if (itlb_multihit_kvm_mitigation)
+		return sysfs_emit(buf, "KVM: Mitigation: Split huge pages\n");
+	else
+		return sysfs_emit(buf, "KVM: Vulnerable\n");
+}
+#else
+static ssize_t l1tf_show_state(char *buf)
+{
+	return sysfs_emit(buf, "%s\n", L1TF_DEFAULT_MSG);
+}
+
+static ssize_t itlb_multihit_show_state(char *buf)
+{
+	return sysfs_emit(buf, "Processor vulnerable\n");
+}
+#endif
+
+static ssize_t mds_show_state(char *buf)
+{
+	if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
+		return sysfs_emit(buf, "%s; SMT Host state unknown\n",
+				  mds_strings[mds_mitigation]);
+	}
+
+	if (boot_cpu_has(X86_BUG_MSBDS_ONLY)) {
+		return sysfs_emit(buf, "%s; SMT %s\n", mds_strings[mds_mitigation],
+				  (mds_mitigation == MDS_MITIGATION_OFF ? "vulnerable" :
+				   sched_smt_active() ? "mitigated" : "disabled"));
+	}
+
+	return sysfs_emit(buf, "%s; SMT %s\n", mds_strings[mds_mitigation],
+			  sched_smt_active() ? "vulnerable" : "disabled");
+}
+
+static ssize_t tsx_async_abort_show_state(char *buf)
+{
+	if ((taa_mitigation == TAA_MITIGATION_TSX_DISABLED) ||
+	    (taa_mitigation == TAA_MITIGATION_OFF))
+		return sysfs_emit(buf, "%s\n", taa_strings[taa_mitigation]);
+
+	if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
+		return sysfs_emit(buf, "%s; SMT Host state unknown\n",
+				  taa_strings[taa_mitigation]);
+	}
+
+	return sysfs_emit(buf, "%s; SMT %s\n", taa_strings[taa_mitigation],
+			  sched_smt_active() ? "vulnerable" : "disabled");
+}
+
+static ssize_t mmio_stale_data_show_state(char *buf)
+{
+	if (boot_cpu_has_bug(X86_BUG_MMIO_UNKNOWN))
+		return sysfs_emit(buf, "Unknown: No mitigations\n");
+
+	if (mmio_mitigation == MMIO_MITIGATION_OFF)
+		return sysfs_emit(buf, "%s\n", mmio_strings[mmio_mitigation]);
+
+	if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
+		return sysfs_emit(buf, "%s; SMT Host state unknown\n",
+				  mmio_strings[mmio_mitigation]);
+	}
+
+	return sysfs_emit(buf, "%s; SMT %s\n", mmio_strings[mmio_mitigation],
+			  sched_smt_active() ? "vulnerable" : "disabled");
+}
+
+static char *stibp_state(void)
+{
+	if (spectre_v2_in_eibrs_mode(spectre_v2_enabled) &&
+	    !boot_cpu_has(X86_FEATURE_AUTOIBRS))
+		return "";
+
+	switch (spectre_v2_user_stibp) {
+	case SPECTRE_V2_USER_NONE:
+		return ", STIBP: disabled";
+	case SPECTRE_V2_USER_STRICT:
+		return ", STIBP: forced";
+	case SPECTRE_V2_USER_STRICT_PREFERRED:
+		return ", STIBP: always-on";
+	case SPECTRE_V2_USER_PRCTL:
+	case SPECTRE_V2_USER_SECCOMP:
+		if (static_key_enabled(&switch_to_cond_stibp))
+			return ", STIBP: conditional";
+	}
+	return "";
+}
+
+static char *ibpb_state(void)
+{
+	if (boot_cpu_has(X86_FEATURE_IBPB)) {
+		if (static_key_enabled(&switch_mm_always_ibpb))
+			return ", IBPB: always-on";
+		if (static_key_enabled(&switch_mm_cond_ibpb))
+			return ", IBPB: conditional";
+		return ", IBPB: disabled";
+	}
+	return "";
+}
+
+static char *pbrsb_eibrs_state(void)
+{
+	if (boot_cpu_has_bug(X86_BUG_EIBRS_PBRSB)) {
+		if (boot_cpu_has(X86_FEATURE_RSB_VMEXIT_LITE) ||
+		    boot_cpu_has(X86_FEATURE_RSB_VMEXIT))
+			return ", PBRSB-eIBRS: SW sequence";
+		else
+			return ", PBRSB-eIBRS: Vulnerable";
+	} else {
+		return ", PBRSB-eIBRS: Not affected";
+	}
+}
+
+static ssize_t spectre_v2_show_state(char *buf)
+{
+	if (spectre_v2_enabled == SPECTRE_V2_LFENCE)
+		return sysfs_emit(buf, "Vulnerable: LFENCE\n");
+
+	if (spectre_v2_enabled == SPECTRE_V2_EIBRS && unprivileged_ebpf_enabled())
+		return sysfs_emit(buf, "Vulnerable: eIBRS with unprivileged eBPF\n");
+
+	if (sched_smt_active() && unprivileged_ebpf_enabled() &&
+	    spectre_v2_enabled == SPECTRE_V2_EIBRS_LFENCE)
+		return sysfs_emit(buf, "Vulnerable: eIBRS+LFENCE with unprivileged eBPF and SMT\n");
+
+	return sysfs_emit(buf, "%s%s%s%s%s%s%s\n",
+			  spectre_v2_strings[spectre_v2_enabled],
+			  ibpb_state(),
+			  boot_cpu_has(X86_FEATURE_USE_IBRS_FW) ? ", IBRS_FW" : "",
+			  stibp_state(),
+			  boot_cpu_has(X86_FEATURE_RSB_CTXSW) ? ", RSB filling" : "",
+			  pbrsb_eibrs_state(),
+			  spectre_v2_module_string());
+}
+
+static ssize_t srbds_show_state(char *buf)
+{
+	return sysfs_emit(buf, "%s\n", srbds_strings[srbds_mitigation]);
+}
+
+static ssize_t retbleed_show_state(char *buf)
+{
+	if (retbleed_mitigation == RETBLEED_MITIGATION_UNRET ||
+	    retbleed_mitigation == RETBLEED_MITIGATION_IBPB) {
+		if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
+		    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
+			return sysfs_emit(buf, "Vulnerable: untrained return thunk / IBPB on non-AMD based uarch\n");
+
+		return sysfs_emit(buf, "%s; SMT %s\n", retbleed_strings[retbleed_mitigation],
+				  !sched_smt_active() ? "disabled" :
+				  spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT ||
+				  spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT_PREFERRED ?
+				  "enabled with STIBP protection" : "vulnerable");
+	}
+
+	return sysfs_emit(buf, "%s\n", retbleed_strings[retbleed_mitigation]);
+}
+
+static ssize_t srso_show_state(char *buf)
+{
+	if (boot_cpu_has(X86_FEATURE_SRSO_NO))
+		return sysfs_emit(buf, "Mitigation: SMT disabled\n");
+
+	return sysfs_emit(buf, "%s\n", srso_strings[srso_mitigation]);
+}
+
+static ssize_t gds_show_state(char *buf)
+{
+	return sysfs_emit(buf, "%s\n", gds_strings[gds_mitigation]);
+}
+
+static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr,
+			       char *buf, unsigned int bug)
+{
+	if (!boot_cpu_has_bug(bug))
+		return sysfs_emit(buf, "Not affected\n");
+
+	switch (bug) {
+	case X86_BUG_CPU_MELTDOWN:
+		if (boot_cpu_has(X86_FEATURE_PTI))
+			return sysfs_emit(buf, "Mitigation: PTI\n");
+
+		if (hypervisor_is_type(X86_HYPER_XEN_PV))
+			return sysfs_emit(buf, "Unknown (XEN PV detected, hypervisor mitigation required)\n");
+
+		break;
+
+	case X86_BUG_SPECTRE_V1:
+		return sysfs_emit(buf, "%s\n", spectre_v1_strings[spectre_v1_mitigation]);
+
+	case X86_BUG_SPECTRE_V2:
+		return spectre_v2_show_state(buf);
+
+	case X86_BUG_SPEC_STORE_BYPASS:
+		return sysfs_emit(buf, "%s\n", ssb_strings[ssb_mode]);
+
+	case X86_BUG_L1TF:
+		if (boot_cpu_has(X86_FEATURE_L1TF_PTEINV))
+			return l1tf_show_state(buf);
+		break;
+
+	case X86_BUG_MDS:
+		return mds_show_state(buf);
+
+	case X86_BUG_TAA:
+		return tsx_async_abort_show_state(buf);
+
+	case X86_BUG_ITLB_MULTIHIT:
+		return itlb_multihit_show_state(buf);
+
+	case X86_BUG_SRBDS:
+		return srbds_show_state(buf);
+
+	case X86_BUG_MMIO_STALE_DATA:
+	case X86_BUG_MMIO_UNKNOWN:
+		return mmio_stale_data_show_state(buf);
+
+	case X86_BUG_RETBLEED:
+		return retbleed_show_state(buf);
+
+	case X86_BUG_SRSO:
+		return srso_show_state(buf);
+
+	case X86_BUG_GDS:
+		return gds_show_state(buf);
+
+	default:
+		break;
+	}
+
+	return sysfs_emit(buf, "Vulnerable\n");
+}
+
+ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_CPU_MELTDOWN);
+}
+
+ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_SPECTRE_V1);
+}
+
+ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_SPECTRE_V2);
+}
+
+ssize_t cpu_show_spec_store_bypass(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_SPEC_STORE_BYPASS);
+}
+
+ssize_t cpu_show_l1tf(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_L1TF);
+}
+
+ssize_t cpu_show_mds(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_MDS);
+}
+
+ssize_t cpu_show_tsx_async_abort(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_TAA);
+}
+
+ssize_t cpu_show_itlb_multihit(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_ITLB_MULTIHIT);
+}
+
+ssize_t cpu_show_srbds(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_SRBDS);
+}
+
+ssize_t cpu_show_mmio_stale_data(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	if (boot_cpu_has_bug(X86_BUG_MMIO_UNKNOWN))
+		return cpu_show_common(dev, attr, buf, X86_BUG_MMIO_UNKNOWN);
+	else
+		return cpu_show_common(dev, attr, buf, X86_BUG_MMIO_STALE_DATA);
+}
+
+ssize_t cpu_show_retbleed(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_RETBLEED);
+}
+
+ssize_t cpu_show_spec_rstack_overflow(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_SRSO);
+}
+
+ssize_t cpu_show_gds(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_GDS);
+}
+#endif
diff --git a/arch/x86/kernel/cpu/cacheinfo.c b/arch/x86/kernel/cpu/cacheinfo.c
new file mode 100644
index 0000000000..8f86eacf69
--- /dev/null
+++ b/arch/x86/kernel/cpu/cacheinfo.c
@@ -0,0 +1,1231 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *	Routines to identify caches on Intel CPU.
+ *
+ *	Changes:
+ *	Venkatesh Pallipadi	: Adding cache identification through cpuid(4)
+ *	Ashok Raj <ashok.raj@intel.com>: Work with CPU hotplug infrastructure.
+ *	Andi Kleen / Andreas Herrmann	: CPUID4 emulation on AMD.
+ */
+
+#include <linux/slab.h>
+#include <linux/cacheinfo.h>
+#include <linux/cpu.h>
+#include <linux/cpuhotplug.h>
+#include <linux/sched.h>
+#include <linux/capability.h>
+#include <linux/sysfs.h>
+#include <linux/pci.h>
+#include <linux/stop_machine.h>
+
+#include <asm/cpufeature.h>
+#include <asm/cacheinfo.h>
+#include <asm/amd_nb.h>
+#include <asm/smp.h>
+#include <asm/mtrr.h>
+#include <asm/tlbflush.h>
+
+#include "cpu.h"
+
+#define LVL_1_INST	1
+#define LVL_1_DATA	2
+#define LVL_2		3
+#define LVL_3		4
+#define LVL_TRACE	5
+
+/* Shared last level cache maps */
+DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map);
+
+/* Shared L2 cache maps */
+DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_l2c_shared_map);
+
+static cpumask_var_t cpu_cacheinfo_mask;
+
+/* Kernel controls MTRR and/or PAT MSRs. */
+unsigned int memory_caching_control __ro_after_init;
+
+struct _cache_table {
+	unsigned char descriptor;
+	char cache_type;
+	short size;
+};
+
+#define MB(x)	((x) * 1024)
+
+/* All the cache descriptor types we care about (no TLB or
+   trace cache entries) */
+
+static const struct _cache_table cache_table[] =
+{
+	{ 0x06, LVL_1_INST, 8 },	/* 4-way set assoc, 32 byte line size */
+	{ 0x08, LVL_1_INST, 16 },	/* 4-way set assoc, 32 byte line size */
+	{ 0x09, LVL_1_INST, 32 },	/* 4-way set assoc, 64 byte line size */
+	{ 0x0a, LVL_1_DATA, 8 },	/* 2 way set assoc, 32 byte line size */
+	{ 0x0c, LVL_1_DATA, 16 },	/* 4-way set assoc, 32 byte line size */
+	{ 0x0d, LVL_1_DATA, 16 },	/* 4-way set assoc, 64 byte line size */
+	{ 0x0e, LVL_1_DATA, 24 },	/* 6-way set assoc, 64 byte line size */
+	{ 0x21, LVL_2,      256 },	/* 8-way set assoc, 64 byte line size */
+	{ 0x22, LVL_3,      512 },	/* 4-way set assoc, sectored cache, 64 byte line size */
+	{ 0x23, LVL_3,      MB(1) },	/* 8-way set assoc, sectored cache, 64 byte line size */
+	{ 0x25, LVL_3,      MB(2) },	/* 8-way set assoc, sectored cache, 64 byte line size */
+	{ 0x29, LVL_3,      MB(4) },	/* 8-way set assoc, sectored cache, 64 byte line size */
+	{ 0x2c, LVL_1_DATA, 32 },	/* 8-way set assoc, 64 byte line size */
+	{ 0x30, LVL_1_INST, 32 },	/* 8-way set assoc, 64 byte line size */
+	{ 0x39, LVL_2,      128 },	/* 4-way set assoc, sectored cache, 64 byte line size */
+	{ 0x3a, LVL_2,      192 },	/* 6-way set assoc, sectored cache, 64 byte line size */
+	{ 0x3b, LVL_2,      128 },	/* 2-way set assoc, sectored cache, 64 byte line size */
+	{ 0x3c, LVL_2,      256 },	/* 4-way set assoc, sectored cache, 64 byte line size */
+	{ 0x3d, LVL_2,      384 },	/* 6-way set assoc, sectored cache, 64 byte line size */
+	{ 0x3e, LVL_2,      512 },	/* 4-way set assoc, sectored cache, 64 byte line size */
+	{ 0x3f, LVL_2,      256 },	/* 2-way set assoc, 64 byte line size */
+	{ 0x41, LVL_2,      128 },	/* 4-way set assoc, 32 byte line size */
+	{ 0x42, LVL_2,      256 },	/* 4-way set assoc, 32 byte line size */
+	{ 0x43, LVL_2,      512 },	/* 4-way set assoc, 32 byte line size */
+	{ 0x44, LVL_2,      MB(1) },	/* 4-way set assoc, 32 byte line size */
+	{ 0x45, LVL_2,      MB(2) },	/* 4-way set assoc, 32 byte line size */
+	{ 0x46, LVL_3,      MB(4) },	/* 4-way set assoc, 64 byte line size */
+	{ 0x47, LVL_3,      MB(8) },	/* 8-way set assoc, 64 byte line size */
+	{ 0x48, LVL_2,      MB(3) },	/* 12-way set assoc, 64 byte line size */
+	{ 0x49, LVL_3,      MB(4) },	/* 16-way set assoc, 64 byte line size */
+	{ 0x4a, LVL_3,      MB(6) },	/* 12-way set assoc, 64 byte line size */
+	{ 0x4b, LVL_3,      MB(8) },	/* 16-way set assoc, 64 byte line size */
+	{ 0x4c, LVL_3,      MB(12) },	/* 12-way set assoc, 64 byte line size */
+	{ 0x4d, LVL_3,      MB(16) },	/* 16-way set assoc, 64 byte line size */
+	{ 0x4e, LVL_2,      MB(6) },	/* 24-way set assoc, 64 byte line size */
+	{ 0x60, LVL_1_DATA, 16 },	/* 8-way set assoc, sectored cache, 64 byte line size */
+	{ 0x66, LVL_1_DATA, 8 },	/* 4-way set assoc, sectored cache, 64 byte line size */
+	{ 0x67, LVL_1_DATA, 16 },	/* 4-way set assoc, sectored cache, 64 byte line size */
+	{ 0x68, LVL_1_DATA, 32 },	/* 4-way set assoc, sectored cache, 64 byte line size */
+	{ 0x70, LVL_TRACE,  12 },	/* 8-way set assoc */
+	{ 0x71, LVL_TRACE,  16 },	/* 8-way set assoc */
+	{ 0x72, LVL_TRACE,  32 },	/* 8-way set assoc */
+	{ 0x73, LVL_TRACE,  64 },	/* 8-way set assoc */
+	{ 0x78, LVL_2,      MB(1) },	/* 4-way set assoc, 64 byte line size */
+	{ 0x79, LVL_2,      128 },	/* 8-way set assoc, sectored cache, 64 byte line size */
+	{ 0x7a, LVL_2,      256 },	/* 8-way set assoc, sectored cache, 64 byte line size */
+	{ 0x7b, LVL_2,      512 },	/* 8-way set assoc, sectored cache, 64 byte line size */
+	{ 0x7c, LVL_2,      MB(1) },	/* 8-way set assoc, sectored cache, 64 byte line size */
+	{ 0x7d, LVL_2,      MB(2) },	/* 8-way set assoc, 64 byte line size */
+	{ 0x7f, LVL_2,      512 },	/* 2-way set assoc, 64 byte line size */
+	{ 0x80, LVL_2,      512 },	/* 8-way set assoc, 64 byte line size */
+	{ 0x82, LVL_2,      256 },	/* 8-way set assoc, 32 byte line size */
+	{ 0x83, LVL_2,      512 },	/* 8-way set assoc, 32 byte line size */
+	{ 0x84, LVL_2,      MB(1) },	/* 8-way set assoc, 32 byte line size */
+	{ 0x85, LVL_2,      MB(2) },	/* 8-way set assoc, 32 byte line size */
+	{ 0x86, LVL_2,      512 },	/* 4-way set assoc, 64 byte line size */
+	{ 0x87, LVL_2,      MB(1) },	/* 8-way set assoc, 64 byte line size */
+	{ 0xd0, LVL_3,      512 },	/* 4-way set assoc, 64 byte line size */
+	{ 0xd1, LVL_3,      MB(1) },	/* 4-way set assoc, 64 byte line size */
+	{ 0xd2, LVL_3,      MB(2) },	/* 4-way set assoc, 64 byte line size */
+	{ 0xd6, LVL_3,      MB(1) },	/* 8-way set assoc, 64 byte line size */
+	{ 0xd7, LVL_3,      MB(2) },	/* 8-way set assoc, 64 byte line size */
+	{ 0xd8, LVL_3,      MB(4) },	/* 12-way set assoc, 64 byte line size */
+	{ 0xdc, LVL_3,      MB(2) },	/* 12-way set assoc, 64 byte line size */
+	{ 0xdd, LVL_3,      MB(4) },	/* 12-way set assoc, 64 byte line size */
+	{ 0xde, LVL_3,      MB(8) },	/* 12-way set assoc, 64 byte line size */
+	{ 0xe2, LVL_3,      MB(2) },	/* 16-way set assoc, 64 byte line size */
+	{ 0xe3, LVL_3,      MB(4) },	/* 16-way set assoc, 64 byte line size */
+	{ 0xe4, LVL_3,      MB(8) },	/* 16-way set assoc, 64 byte line size */
+	{ 0xea, LVL_3,      MB(12) },	/* 24-way set assoc, 64 byte line size */
+	{ 0xeb, LVL_3,      MB(18) },	/* 24-way set assoc, 64 byte line size */
+	{ 0xec, LVL_3,      MB(24) },	/* 24-way set assoc, 64 byte line size */
+	{ 0x00, 0, 0}
+};
+
+
+enum _cache_type {
+	CTYPE_NULL = 0,
+	CTYPE_DATA = 1,
+	CTYPE_INST = 2,
+	CTYPE_UNIFIED = 3
+};
+
+union _cpuid4_leaf_eax {
+	struct {
+		enum _cache_type	type:5;
+		unsigned int		level:3;
+		unsigned int		is_self_initializing:1;
+		unsigned int		is_fully_associative:1;
+		unsigned int		reserved:4;
+		unsigned int		num_threads_sharing:12;
+		unsigned int		num_cores_on_die:6;
+	} split;
+	u32 full;
+};
+
+union _cpuid4_leaf_ebx {
+	struct {
+		unsigned int		coherency_line_size:12;
+		unsigned int		physical_line_partition:10;
+		unsigned int		ways_of_associativity:10;
+	} split;
+	u32 full;
+};
+
+union _cpuid4_leaf_ecx {
+	struct {
+		unsigned int		number_of_sets:32;
+	} split;
+	u32 full;
+};
+
+struct _cpuid4_info_regs {
+	union _cpuid4_leaf_eax eax;
+	union _cpuid4_leaf_ebx ebx;
+	union _cpuid4_leaf_ecx ecx;
+	unsigned int id;
+	unsigned long size;
+	struct amd_northbridge *nb;
+};
+
+static unsigned short num_cache_leaves;
+
+/* AMD doesn't have CPUID4. Emulate it here to report the same
+   information to the user.  This makes some assumptions about the machine:
+   L2 not shared, no SMT etc. that is currently true on AMD CPUs.
+
+   In theory the TLBs could be reported as fake type (they are in "dummy").
+   Maybe later */
+union l1_cache {
+	struct {
+		unsigned line_size:8;
+		unsigned lines_per_tag:8;
+		unsigned assoc:8;
+		unsigned size_in_kb:8;
+	};
+	unsigned val;
+};
+
+union l2_cache {
+	struct {
+		unsigned line_size:8;
+		unsigned lines_per_tag:4;
+		unsigned assoc:4;
+		unsigned size_in_kb:16;
+	};
+	unsigned val;
+};
+
+union l3_cache {
+	struct {
+		unsigned line_size:8;
+		unsigned lines_per_tag:4;
+		unsigned assoc:4;
+		unsigned res:2;
+		unsigned size_encoded:14;
+	};
+	unsigned val;
+};
+
+static const unsigned short assocs[] = {
+	[1] = 1,
+	[2] = 2,
+	[4] = 4,
+	[6] = 8,
+	[8] = 16,
+	[0xa] = 32,
+	[0xb] = 48,
+	[0xc] = 64,
+	[0xd] = 96,
+	[0xe] = 128,
+	[0xf] = 0xffff /* fully associative - no way to show this currently */
+};
+
+static const unsigned char levels[] = { 1, 1, 2, 3 };
+static const unsigned char types[] = { 1, 2, 3, 3 };
+
+static const enum cache_type cache_type_map[] = {
+	[CTYPE_NULL] = CACHE_TYPE_NOCACHE,
+	[CTYPE_DATA] = CACHE_TYPE_DATA,
+	[CTYPE_INST] = CACHE_TYPE_INST,
+	[CTYPE_UNIFIED] = CACHE_TYPE_UNIFIED,
+};
+
+static void
+amd_cpuid4(int leaf, union _cpuid4_leaf_eax *eax,
+		     union _cpuid4_leaf_ebx *ebx,
+		     union _cpuid4_leaf_ecx *ecx)
+{
+	unsigned dummy;
+	unsigned line_size, lines_per_tag, assoc, size_in_kb;
+	union l1_cache l1i, l1d;
+	union l2_cache l2;
+	union l3_cache l3;
+	union l1_cache *l1 = &l1d;
+
+	eax->full = 0;
+	ebx->full = 0;
+	ecx->full = 0;
+
+	cpuid(0x80000005, &dummy, &dummy, &l1d.val, &l1i.val);
+	cpuid(0x80000006, &dummy, &dummy, &l2.val, &l3.val);
+
+	switch (leaf) {
+	case 1:
+		l1 = &l1i;
+		fallthrough;
+	case 0:
+		if (!l1->val)
+			return;
+		assoc = assocs[l1->assoc];
+		line_size = l1->line_size;
+		lines_per_tag = l1->lines_per_tag;
+		size_in_kb = l1->size_in_kb;
+		break;
+	case 2:
+		if (!l2.val)
+			return;
+		assoc = assocs[l2.assoc];
+		line_size = l2.line_size;
+		lines_per_tag = l2.lines_per_tag;
+		/* cpu_data has errata corrections for K7 applied */
+		size_in_kb = __this_cpu_read(cpu_info.x86_cache_size);
+		break;
+	case 3:
+		if (!l3.val)
+			return;
+		assoc = assocs[l3.assoc];
+		line_size = l3.line_size;
+		lines_per_tag = l3.lines_per_tag;
+		size_in_kb = l3.size_encoded * 512;
+		if (boot_cpu_has(X86_FEATURE_AMD_DCM)) {
+			size_in_kb = size_in_kb >> 1;
+			assoc = assoc >> 1;
+		}
+		break;
+	default:
+		return;
+	}
+
+	eax->split.is_self_initializing = 1;
+	eax->split.type = types[leaf];
+	eax->split.level = levels[leaf];
+	eax->split.num_threads_sharing = 0;
+	eax->split.num_cores_on_die = __this_cpu_read(cpu_info.x86_max_cores) - 1;
+
+
+	if (assoc == 0xffff)
+		eax->split.is_fully_associative = 1;
+	ebx->split.coherency_line_size = line_size - 1;
+	ebx->split.ways_of_associativity = assoc - 1;
+	ebx->split.physical_line_partition = lines_per_tag - 1;
+	ecx->split.number_of_sets = (size_in_kb * 1024) / line_size /
+		(ebx->split.ways_of_associativity + 1) - 1;
+}
+
+#if defined(CONFIG_AMD_NB) && defined(CONFIG_SYSFS)
+
+/*
+ * L3 cache descriptors
+ */
+static void amd_calc_l3_indices(struct amd_northbridge *nb)
+{
+	struct amd_l3_cache *l3 = &nb->l3_cache;
+	unsigned int sc0, sc1, sc2, sc3;
+	u32 val = 0;
+
+	pci_read_config_dword(nb->misc, 0x1C4, &val);
+
+	/* calculate subcache sizes */
+	l3->subcaches[0] = sc0 = !(val & BIT(0));
+	l3->subcaches[1] = sc1 = !(val & BIT(4));
+
+	if (boot_cpu_data.x86 == 0x15) {
+		l3->subcaches[0] = sc0 += !(val & BIT(1));
+		l3->subcaches[1] = sc1 += !(val & BIT(5));
+	}
+
+	l3->subcaches[2] = sc2 = !(val & BIT(8))  + !(val & BIT(9));
+	l3->subcaches[3] = sc3 = !(val & BIT(12)) + !(val & BIT(13));
+
+	l3->indices = (max(max3(sc0, sc1, sc2), sc3) << 10) - 1;
+}
+
+/*
+ * check whether a slot used for disabling an L3 index is occupied.
+ * @l3: L3 cache descriptor
+ * @slot: slot number (0..1)
+ *
+ * @returns: the disabled index if used or negative value if slot free.
+ */
+static int amd_get_l3_disable_slot(struct amd_northbridge *nb, unsigned slot)
+{
+	unsigned int reg = 0;
+
+	pci_read_config_dword(nb->misc, 0x1BC + slot * 4, &reg);
+
+	/* check whether this slot is activated already */
+	if (reg & (3UL << 30))
+		return reg & 0xfff;
+
+	return -1;
+}
+
+static ssize_t show_cache_disable(struct cacheinfo *this_leaf, char *buf,
+				  unsigned int slot)
+{
+	int index;
+	struct amd_northbridge *nb = this_leaf->priv;
+
+	index = amd_get_l3_disable_slot(nb, slot);
+	if (index >= 0)
+		return sprintf(buf, "%d\n", index);
+
+	return sprintf(buf, "FREE\n");
+}
+
+#define SHOW_CACHE_DISABLE(slot)					\
+static ssize_t								\
+cache_disable_##slot##_show(struct device *dev,				\
+			    struct device_attribute *attr, char *buf)	\
+{									\
+	struct cacheinfo *this_leaf = dev_get_drvdata(dev);		\
+	return show_cache_disable(this_leaf, buf, slot);		\
+}
+SHOW_CACHE_DISABLE(0)
+SHOW_CACHE_DISABLE(1)
+
+static void amd_l3_disable_index(struct amd_northbridge *nb, int cpu,
+				 unsigned slot, unsigned long idx)
+{
+	int i;
+
+	idx |= BIT(30);
+
+	/*
+	 *  disable index in all 4 subcaches
+	 */
+	for (i = 0; i < 4; i++) {
+		u32 reg = idx | (i << 20);
+
+		if (!nb->l3_cache.subcaches[i])
+			continue;
+
+		pci_write_config_dword(nb->misc, 0x1BC + slot * 4, reg);
+
+		/*
+		 * We need to WBINVD on a core on the node containing the L3
+		 * cache which indices we disable therefore a simple wbinvd()
+		 * is not sufficient.
+		 */
+		wbinvd_on_cpu(cpu);
+
+		reg |= BIT(31);
+		pci_write_config_dword(nb->misc, 0x1BC + slot * 4, reg);
+	}
+}
+
+/*
+ * disable a L3 cache index by using a disable-slot
+ *
+ * @l3:    L3 cache descriptor
+ * @cpu:   A CPU on the node containing the L3 cache
+ * @slot:  slot number (0..1)
+ * @index: index to disable
+ *
+ * @return: 0 on success, error status on failure
+ */
+static int amd_set_l3_disable_slot(struct amd_northbridge *nb, int cpu,
+			    unsigned slot, unsigned long index)
+{
+	int ret = 0;
+
+	/*  check if @slot is already used or the index is already disabled */
+	ret = amd_get_l3_disable_slot(nb, slot);
+	if (ret >= 0)
+		return -EEXIST;
+
+	if (index > nb->l3_cache.indices)
+		return -EINVAL;
+
+	/* check whether the other slot has disabled the same index already */
+	if (index == amd_get_l3_disable_slot(nb, !slot))
+		return -EEXIST;
+
+	amd_l3_disable_index(nb, cpu, slot, index);
+
+	return 0;
+}
+
+static ssize_t store_cache_disable(struct cacheinfo *this_leaf,
+				   const char *buf, size_t count,
+				   unsigned int slot)
+{
+	unsigned long val = 0;
+	int cpu, err = 0;
+	struct amd_northbridge *nb = this_leaf->priv;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	cpu = cpumask_first(&this_leaf->shared_cpu_map);
+
+	if (kstrtoul(buf, 10, &val) < 0)
+		return -EINVAL;
+
+	err = amd_set_l3_disable_slot(nb, cpu, slot, val);
+	if (err) {
+		if (err == -EEXIST)
+			pr_warn("L3 slot %d in use/index already disabled!\n",
+				   slot);
+		return err;
+	}
+	return count;
+}
+
+#define STORE_CACHE_DISABLE(slot)					\
+static ssize_t								\
+cache_disable_##slot##_store(struct device *dev,			\
+			     struct device_attribute *attr,		\
+			     const char *buf, size_t count)		\
+{									\
+	struct cacheinfo *this_leaf = dev_get_drvdata(dev);		\
+	return store_cache_disable(this_leaf, buf, count, slot);	\
+}
+STORE_CACHE_DISABLE(0)
+STORE_CACHE_DISABLE(1)
+
+static ssize_t subcaches_show(struct device *dev,
+			      struct device_attribute *attr, char *buf)
+{
+	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
+	int cpu = cpumask_first(&this_leaf->shared_cpu_map);
+
+	return sprintf(buf, "%x\n", amd_get_subcaches(cpu));
+}
+
+static ssize_t subcaches_store(struct device *dev,
+			       struct device_attribute *attr,
+			       const char *buf, size_t count)
+{
+	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
+	int cpu = cpumask_first(&this_leaf->shared_cpu_map);
+	unsigned long val;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	if (kstrtoul(buf, 16, &val) < 0)
+		return -EINVAL;
+
+	if (amd_set_subcaches(cpu, val))
+		return -EINVAL;
+
+	return count;
+}
+
+static DEVICE_ATTR_RW(cache_disable_0);
+static DEVICE_ATTR_RW(cache_disable_1);
+static DEVICE_ATTR_RW(subcaches);
+
+static umode_t
+cache_private_attrs_is_visible(struct kobject *kobj,
+			       struct attribute *attr, int unused)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
+	umode_t mode = attr->mode;
+
+	if (!this_leaf->priv)
+		return 0;
+
+	if ((attr == &dev_attr_subcaches.attr) &&
+	    amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
+		return mode;
+
+	if ((attr == &dev_attr_cache_disable_0.attr ||
+	     attr == &dev_attr_cache_disable_1.attr) &&
+	    amd_nb_has_feature(AMD_NB_L3_INDEX_DISABLE))
+		return mode;
+
+	return 0;
+}
+
+static struct attribute_group cache_private_group = {
+	.is_visible = cache_private_attrs_is_visible,
+};
+
+static void init_amd_l3_attrs(void)
+{
+	int n = 1;
+	static struct attribute **amd_l3_attrs;
+
+	if (amd_l3_attrs) /* already initialized */
+		return;
+
+	if (amd_nb_has_feature(AMD_NB_L3_INDEX_DISABLE))
+		n += 2;
+	if (amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
+		n += 1;
+
+	amd_l3_attrs = kcalloc(n, sizeof(*amd_l3_attrs), GFP_KERNEL);
+	if (!amd_l3_attrs)
+		return;
+
+	n = 0;
+	if (amd_nb_has_feature(AMD_NB_L3_INDEX_DISABLE)) {
+		amd_l3_attrs[n++] = &dev_attr_cache_disable_0.attr;
+		amd_l3_attrs[n++] = &dev_attr_cache_disable_1.attr;
+	}
+	if (amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
+		amd_l3_attrs[n++] = &dev_attr_subcaches.attr;
+
+	cache_private_group.attrs = amd_l3_attrs;
+}
+
+const struct attribute_group *
+cache_get_priv_group(struct cacheinfo *this_leaf)
+{
+	struct amd_northbridge *nb = this_leaf->priv;
+
+	if (this_leaf->level < 3 || !nb)
+		return NULL;
+
+	if (nb && nb->l3_cache.indices)
+		init_amd_l3_attrs();
+
+	return &cache_private_group;
+}
+
+static void amd_init_l3_cache(struct _cpuid4_info_regs *this_leaf, int index)
+{
+	int node;
+
+	/* only for L3, and not in virtualized environments */
+	if (index < 3)
+		return;
+
+	node = topology_die_id(smp_processor_id());
+	this_leaf->nb = node_to_amd_nb(node);
+	if (this_leaf->nb && !this_leaf->nb->l3_cache.indices)
+		amd_calc_l3_indices(this_leaf->nb);
+}
+#else
+#define amd_init_l3_cache(x, y)
+#endif  /* CONFIG_AMD_NB && CONFIG_SYSFS */
+
+static int
+cpuid4_cache_lookup_regs(int index, struct _cpuid4_info_regs *this_leaf)
+{
+	union _cpuid4_leaf_eax	eax;
+	union _cpuid4_leaf_ebx	ebx;
+	union _cpuid4_leaf_ecx	ecx;
+	unsigned		edx;
+
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
+		if (boot_cpu_has(X86_FEATURE_TOPOEXT))
+			cpuid_count(0x8000001d, index, &eax.full,
+				    &ebx.full, &ecx.full, &edx);
+		else
+			amd_cpuid4(index, &eax, &ebx, &ecx);
+		amd_init_l3_cache(this_leaf, index);
+	} else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
+		cpuid_count(0x8000001d, index, &eax.full,
+			    &ebx.full, &ecx.full, &edx);
+		amd_init_l3_cache(this_leaf, index);
+	} else {
+		cpuid_count(4, index, &eax.full, &ebx.full, &ecx.full, &edx);
+	}
+
+	if (eax.split.type == CTYPE_NULL)
+		return -EIO; /* better error ? */
+
+	this_leaf->eax = eax;
+	this_leaf->ebx = ebx;
+	this_leaf->ecx = ecx;
+	this_leaf->size = (ecx.split.number_of_sets          + 1) *
+			  (ebx.split.coherency_line_size     + 1) *
+			  (ebx.split.physical_line_partition + 1) *
+			  (ebx.split.ways_of_associativity   + 1);
+	return 0;
+}
+
+static int find_num_cache_leaves(struct cpuinfo_x86 *c)
+{
+	unsigned int		eax, ebx, ecx, edx, op;
+	union _cpuid4_leaf_eax	cache_eax;
+	int 			i = -1;
+
+	if (c->x86_vendor == X86_VENDOR_AMD ||
+	    c->x86_vendor == X86_VENDOR_HYGON)
+		op = 0x8000001d;
+	else
+		op = 4;
+
+	do {
+		++i;
+		/* Do cpuid(op) loop to find out num_cache_leaves */
+		cpuid_count(op, i, &eax, &ebx, &ecx, &edx);
+		cache_eax.full = eax;
+	} while (cache_eax.split.type != CTYPE_NULL);
+	return i;
+}
+
+void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c, int cpu)
+{
+	/*
+	 * We may have multiple LLCs if L3 caches exist, so check if we
+	 * have an L3 cache by looking at the L3 cache CPUID leaf.
+	 */
+	if (!cpuid_edx(0x80000006))
+		return;
+
+	if (c->x86 < 0x17) {
+		/* LLC is at the node level. */
+		per_cpu(cpu_llc_id, cpu) = c->cpu_die_id;
+	} else if (c->x86 == 0x17 && c->x86_model <= 0x1F) {
+		/*
+		 * LLC is at the core complex level.
+		 * Core complex ID is ApicId[3] for these processors.
+		 */
+		per_cpu(cpu_llc_id, cpu) = c->apicid >> 3;
+	} else {
+		/*
+		 * LLC ID is calculated from the number of threads sharing the
+		 * cache.
+		 * */
+		u32 eax, ebx, ecx, edx, num_sharing_cache = 0;
+		u32 llc_index = find_num_cache_leaves(c) - 1;
+
+		cpuid_count(0x8000001d, llc_index, &eax, &ebx, &ecx, &edx);
+		if (eax)
+			num_sharing_cache = ((eax >> 14) & 0xfff) + 1;
+
+		if (num_sharing_cache) {
+			int bits = get_count_order(num_sharing_cache);
+
+			per_cpu(cpu_llc_id, cpu) = c->apicid >> bits;
+		}
+	}
+}
+
+void cacheinfo_hygon_init_llc_id(struct cpuinfo_x86 *c, int cpu)
+{
+	/*
+	 * We may have multiple LLCs if L3 caches exist, so check if we
+	 * have an L3 cache by looking at the L3 cache CPUID leaf.
+	 */
+	if (!cpuid_edx(0x80000006))
+		return;
+
+	/*
+	 * LLC is at the core complex level.
+	 * Core complex ID is ApicId[3] for these processors.
+	 */
+	per_cpu(cpu_llc_id, cpu) = c->apicid >> 3;
+}
+
+void init_amd_cacheinfo(struct cpuinfo_x86 *c)
+{
+
+	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
+		num_cache_leaves = find_num_cache_leaves(c);
+	} else if (c->extended_cpuid_level >= 0x80000006) {
+		if (cpuid_edx(0x80000006) & 0xf000)
+			num_cache_leaves = 4;
+		else
+			num_cache_leaves = 3;
+	}
+}
+
+void init_hygon_cacheinfo(struct cpuinfo_x86 *c)
+{
+	num_cache_leaves = find_num_cache_leaves(c);
+}
+
+void init_intel_cacheinfo(struct cpuinfo_x86 *c)
+{
+	/* Cache sizes */
+	unsigned int l1i = 0, l1d = 0, l2 = 0, l3 = 0;
+	unsigned int new_l1d = 0, new_l1i = 0; /* Cache sizes from cpuid(4) */
+	unsigned int new_l2 = 0, new_l3 = 0, i; /* Cache sizes from cpuid(4) */
+	unsigned int l2_id = 0, l3_id = 0, num_threads_sharing, index_msb;
+#ifdef CONFIG_SMP
+	unsigned int cpu = c->cpu_index;
+#endif
+
+	if (c->cpuid_level > 3) {
+		static int is_initialized;
+
+		if (is_initialized == 0) {
+			/* Init num_cache_leaves from boot CPU */
+			num_cache_leaves = find_num_cache_leaves(c);
+			is_initialized++;
+		}
+
+		/*
+		 * Whenever possible use cpuid(4), deterministic cache
+		 * parameters cpuid leaf to find the cache details
+		 */
+		for (i = 0; i < num_cache_leaves; i++) {
+			struct _cpuid4_info_regs this_leaf = {};
+			int retval;
+
+			retval = cpuid4_cache_lookup_regs(i, &this_leaf);
+			if (retval < 0)
+				continue;
+
+			switch (this_leaf.eax.split.level) {
+			case 1:
+				if (this_leaf.eax.split.type == CTYPE_DATA)
+					new_l1d = this_leaf.size/1024;
+				else if (this_leaf.eax.split.type == CTYPE_INST)
+					new_l1i = this_leaf.size/1024;
+				break;
+			case 2:
+				new_l2 = this_leaf.size/1024;
+				num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing;
+				index_msb = get_count_order(num_threads_sharing);
+				l2_id = c->apicid & ~((1 << index_msb) - 1);
+				break;
+			case 3:
+				new_l3 = this_leaf.size/1024;
+				num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing;
+				index_msb = get_count_order(num_threads_sharing);
+				l3_id = c->apicid & ~((1 << index_msb) - 1);
+				break;
+			default:
+				break;
+			}
+		}
+	}
+	/*
+	 * Don't use cpuid2 if cpuid4 is supported. For P4, we use cpuid2 for
+	 * trace cache
+	 */
+	if ((num_cache_leaves == 0 || c->x86 == 15) && c->cpuid_level > 1) {
+		/* supports eax=2  call */
+		int j, n;
+		unsigned int regs[4];
+		unsigned char *dp = (unsigned char *)regs;
+		int only_trace = 0;
+
+		if (num_cache_leaves != 0 && c->x86 == 15)
+			only_trace = 1;
+
+		/* Number of times to iterate */
+		n = cpuid_eax(2) & 0xFF;
+
+		for (i = 0 ; i < n ; i++) {
+			cpuid(2, &regs[0], &regs[1], &regs[2], &regs[3]);
+
+			/* If bit 31 is set, this is an unknown format */
+			for (j = 0 ; j < 3 ; j++)
+				if (regs[j] & (1 << 31))
+					regs[j] = 0;
+
+			/* Byte 0 is level count, not a descriptor */
+			for (j = 1 ; j < 16 ; j++) {
+				unsigned char des = dp[j];
+				unsigned char k = 0;
+
+				/* look up this descriptor in the table */
+				while (cache_table[k].descriptor != 0) {
+					if (cache_table[k].descriptor == des) {
+						if (only_trace && cache_table[k].cache_type != LVL_TRACE)
+							break;
+						switch (cache_table[k].cache_type) {
+						case LVL_1_INST:
+							l1i += cache_table[k].size;
+							break;
+						case LVL_1_DATA:
+							l1d += cache_table[k].size;
+							break;
+						case LVL_2:
+							l2 += cache_table[k].size;
+							break;
+						case LVL_3:
+							l3 += cache_table[k].size;
+							break;
+						}
+
+						break;
+					}
+
+					k++;
+				}
+			}
+		}
+	}
+
+	if (new_l1d)
+		l1d = new_l1d;
+
+	if (new_l1i)
+		l1i = new_l1i;
+
+	if (new_l2) {
+		l2 = new_l2;
+#ifdef CONFIG_SMP
+		per_cpu(cpu_llc_id, cpu) = l2_id;
+		per_cpu(cpu_l2c_id, cpu) = l2_id;
+#endif
+	}
+
+	if (new_l3) {
+		l3 = new_l3;
+#ifdef CONFIG_SMP
+		per_cpu(cpu_llc_id, cpu) = l3_id;
+#endif
+	}
+
+#ifdef CONFIG_SMP
+	/*
+	 * If cpu_llc_id is not yet set, this means cpuid_level < 4 which in
+	 * turns means that the only possibility is SMT (as indicated in
+	 * cpuid1). Since cpuid2 doesn't specify shared caches, and we know
+	 * that SMT shares all caches, we can unconditionally set cpu_llc_id to
+	 * c->phys_proc_id.
+	 */
+	if (per_cpu(cpu_llc_id, cpu) == BAD_APICID)
+		per_cpu(cpu_llc_id, cpu) = c->phys_proc_id;
+#endif
+
+	c->x86_cache_size = l3 ? l3 : (l2 ? l2 : (l1i+l1d));
+
+	if (!l2)
+		cpu_detect_cache_sizes(c);
+}
+
+static int __cache_amd_cpumap_setup(unsigned int cpu, int index,
+				    struct _cpuid4_info_regs *base)
+{
+	struct cpu_cacheinfo *this_cpu_ci;
+	struct cacheinfo *this_leaf;
+	int i, sibling;
+
+	/*
+	 * For L3, always use the pre-calculated cpu_llc_shared_mask
+	 * to derive shared_cpu_map.
+	 */
+	if (index == 3) {
+		for_each_cpu(i, cpu_llc_shared_mask(cpu)) {
+			this_cpu_ci = get_cpu_cacheinfo(i);
+			if (!this_cpu_ci->info_list)
+				continue;
+			this_leaf = this_cpu_ci->info_list + index;
+			for_each_cpu(sibling, cpu_llc_shared_mask(cpu)) {
+				if (!cpu_online(sibling))
+					continue;
+				cpumask_set_cpu(sibling,
+						&this_leaf->shared_cpu_map);
+			}
+		}
+	} else if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
+		unsigned int apicid, nshared, first, last;
+
+		nshared = base->eax.split.num_threads_sharing + 1;
+		apicid = cpu_data(cpu).apicid;
+		first = apicid - (apicid % nshared);
+		last = first + nshared - 1;
+
+		for_each_online_cpu(i) {
+			this_cpu_ci = get_cpu_cacheinfo(i);
+			if (!this_cpu_ci->info_list)
+				continue;
+
+			apicid = cpu_data(i).apicid;
+			if ((apicid < first) || (apicid > last))
+				continue;
+
+			this_leaf = this_cpu_ci->info_list + index;
+
+			for_each_online_cpu(sibling) {
+				apicid = cpu_data(sibling).apicid;
+				if ((apicid < first) || (apicid > last))
+					continue;
+				cpumask_set_cpu(sibling,
+						&this_leaf->shared_cpu_map);
+			}
+		}
+	} else
+		return 0;
+
+	return 1;
+}
+
+static void __cache_cpumap_setup(unsigned int cpu, int index,
+				 struct _cpuid4_info_regs *base)
+{
+	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+	struct cacheinfo *this_leaf, *sibling_leaf;
+	unsigned long num_threads_sharing;
+	int index_msb, i;
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+
+	if (c->x86_vendor == X86_VENDOR_AMD ||
+	    c->x86_vendor == X86_VENDOR_HYGON) {
+		if (__cache_amd_cpumap_setup(cpu, index, base))
+			return;
+	}
+
+	this_leaf = this_cpu_ci->info_list + index;
+	num_threads_sharing = 1 + base->eax.split.num_threads_sharing;
+
+	cpumask_set_cpu(cpu, &this_leaf->shared_cpu_map);
+	if (num_threads_sharing == 1)
+		return;
+
+	index_msb = get_count_order(num_threads_sharing);
+
+	for_each_online_cpu(i)
+		if (cpu_data(i).apicid >> index_msb == c->apicid >> index_msb) {
+			struct cpu_cacheinfo *sib_cpu_ci = get_cpu_cacheinfo(i);
+
+			if (i == cpu || !sib_cpu_ci->info_list)
+				continue;/* skip if itself or no cacheinfo */
+			sibling_leaf = sib_cpu_ci->info_list + index;
+			cpumask_set_cpu(i, &this_leaf->shared_cpu_map);
+			cpumask_set_cpu(cpu, &sibling_leaf->shared_cpu_map);
+		}
+}
+
+static void ci_leaf_init(struct cacheinfo *this_leaf,
+			 struct _cpuid4_info_regs *base)
+{
+	this_leaf->id = base->id;
+	this_leaf->attributes = CACHE_ID;
+	this_leaf->level = base->eax.split.level;
+	this_leaf->type = cache_type_map[base->eax.split.type];
+	this_leaf->coherency_line_size =
+				base->ebx.split.coherency_line_size + 1;
+	this_leaf->ways_of_associativity =
+				base->ebx.split.ways_of_associativity + 1;
+	this_leaf->size = base->size;
+	this_leaf->number_of_sets = base->ecx.split.number_of_sets + 1;
+	this_leaf->physical_line_partition =
+				base->ebx.split.physical_line_partition + 1;
+	this_leaf->priv = base->nb;
+}
+
+int init_cache_level(unsigned int cpu)
+{
+	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+
+	if (!num_cache_leaves)
+		return -ENOENT;
+	if (!this_cpu_ci)
+		return -EINVAL;
+	this_cpu_ci->num_levels = 3;
+	this_cpu_ci->num_leaves = num_cache_leaves;
+	return 0;
+}
+
+/*
+ * The max shared threads number comes from CPUID.4:EAX[25-14] with input
+ * ECX as cache index. Then right shift apicid by the number's order to get
+ * cache id for this cache node.
+ */
+static void get_cache_id(int cpu, struct _cpuid4_info_regs *id4_regs)
+{
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	unsigned long num_threads_sharing;
+	int index_msb;
+
+	num_threads_sharing = 1 + id4_regs->eax.split.num_threads_sharing;
+	index_msb = get_count_order(num_threads_sharing);
+	id4_regs->id = c->apicid >> index_msb;
+}
+
+int populate_cache_leaves(unsigned int cpu)
+{
+	unsigned int idx, ret;
+	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+	struct cacheinfo *this_leaf = this_cpu_ci->info_list;
+	struct _cpuid4_info_regs id4_regs = {};
+
+	for (idx = 0; idx < this_cpu_ci->num_leaves; idx++) {
+		ret = cpuid4_cache_lookup_regs(idx, &id4_regs);
+		if (ret)
+			return ret;
+		get_cache_id(cpu, &id4_regs);
+		ci_leaf_init(this_leaf++, &id4_regs);
+		__cache_cpumap_setup(cpu, idx, &id4_regs);
+	}
+	this_cpu_ci->cpu_map_populated = true;
+
+	return 0;
+}
+
+/*
+ * Disable and enable caches. Needed for changing MTRRs and the PAT MSR.
+ *
+ * Since we are disabling the cache don't allow any interrupts,
+ * they would run extremely slow and would only increase the pain.
+ *
+ * The caller must ensure that local interrupts are disabled and
+ * are reenabled after cache_enable() has been called.
+ */
+static unsigned long saved_cr4;
+static DEFINE_RAW_SPINLOCK(cache_disable_lock);
+
+void cache_disable(void) __acquires(cache_disable_lock)
+{
+	unsigned long cr0;
+
+	/*
+	 * Note that this is not ideal
+	 * since the cache is only flushed/disabled for this CPU while the
+	 * MTRRs are changed, but changing this requires more invasive
+	 * changes to the way the kernel boots
+	 */
+
+	raw_spin_lock(&cache_disable_lock);
+
+	/* Enter the no-fill (CD=1, NW=0) cache mode and flush caches. */
+	cr0 = read_cr0() | X86_CR0_CD;
+	write_cr0(cr0);
+
+	/*
+	 * Cache flushing is the most time-consuming step when programming
+	 * the MTRRs. Fortunately, as per the Intel Software Development
+	 * Manual, we can skip it if the processor supports cache self-
+	 * snooping.
+	 */
+	if (!static_cpu_has(X86_FEATURE_SELFSNOOP))
+		wbinvd();
+
+	/* Save value of CR4 and clear Page Global Enable (bit 7) */
+	if (cpu_feature_enabled(X86_FEATURE_PGE)) {
+		saved_cr4 = __read_cr4();
+		__write_cr4(saved_cr4 & ~X86_CR4_PGE);
+	}
+
+	/* Flush all TLBs via a mov %cr3, %reg; mov %reg, %cr3 */
+	count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL);
+	flush_tlb_local();
+
+	if (cpu_feature_enabled(X86_FEATURE_MTRR))
+		mtrr_disable();
+
+	/* Again, only flush caches if we have to. */
+	if (!static_cpu_has(X86_FEATURE_SELFSNOOP))
+		wbinvd();
+}
+
+void cache_enable(void) __releases(cache_disable_lock)
+{
+	/* Flush TLBs (no need to flush caches - they are disabled) */
+	count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL);
+	flush_tlb_local();
+
+	if (cpu_feature_enabled(X86_FEATURE_MTRR))
+		mtrr_enable();
+
+	/* Enable caches */
+	write_cr0(read_cr0() & ~X86_CR0_CD);
+
+	/* Restore value of CR4 */
+	if (cpu_feature_enabled(X86_FEATURE_PGE))
+		__write_cr4(saved_cr4);
+
+	raw_spin_unlock(&cache_disable_lock);
+}
+
+static void cache_cpu_init(void)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	cache_disable();
+
+	if (memory_caching_control & CACHE_MTRR)
+		mtrr_generic_set_state();
+
+	if (memory_caching_control & CACHE_PAT)
+		pat_cpu_init();
+
+	cache_enable();
+	local_irq_restore(flags);
+}
+
+static bool cache_aps_delayed_init = true;
+
+void set_cache_aps_delayed_init(bool val)
+{
+	cache_aps_delayed_init = val;
+}
+
+bool get_cache_aps_delayed_init(void)
+{
+	return cache_aps_delayed_init;
+}
+
+static int cache_rendezvous_handler(void *unused)
+{
+	if (get_cache_aps_delayed_init() || !cpu_online(smp_processor_id()))
+		cache_cpu_init();
+
+	return 0;
+}
+
+void __init cache_bp_init(void)
+{
+	mtrr_bp_init();
+	pat_bp_init();
+
+	if (memory_caching_control)
+		cache_cpu_init();
+}
+
+void cache_bp_restore(void)
+{
+	if (memory_caching_control)
+		cache_cpu_init();
+}
+
+static int cache_ap_online(unsigned int cpu)
+{
+	cpumask_set_cpu(cpu, cpu_cacheinfo_mask);
+
+	if (!memory_caching_control || get_cache_aps_delayed_init())
+		return 0;
+
+	/*
+	 * Ideally we should hold mtrr_mutex here to avoid MTRR entries
+	 * changed, but this routine will be called in CPU boot time,
+	 * holding the lock breaks it.
+	 *
+	 * This routine is called in two cases:
+	 *
+	 *   1. very early time of software resume, when there absolutely
+	 *      isn't MTRR entry changes;
+	 *
+	 *   2. CPU hotadd time. We let mtrr_add/del_page hold cpuhotplug
+	 *      lock to prevent MTRR entry changes
+	 */
+	stop_machine_from_inactive_cpu(cache_rendezvous_handler, NULL,
+				       cpu_cacheinfo_mask);
+
+	return 0;
+}
+
+static int cache_ap_offline(unsigned int cpu)
+{
+	cpumask_clear_cpu(cpu, cpu_cacheinfo_mask);
+	return 0;
+}
+
+/*
+ * Delayed cache initialization for all AP's
+ */
+void cache_aps_init(void)
+{
+	if (!memory_caching_control || !get_cache_aps_delayed_init())
+		return;
+
+	stop_machine(cache_rendezvous_handler, NULL, cpu_online_mask);
+	set_cache_aps_delayed_init(false);
+}
+
+static int __init cache_ap_register(void)
+{
+	zalloc_cpumask_var(&cpu_cacheinfo_mask, GFP_KERNEL);
+	cpumask_set_cpu(smp_processor_id(), cpu_cacheinfo_mask);
+
+	cpuhp_setup_state_nocalls(CPUHP_AP_CACHECTRL_STARTING,
+				  "x86/cachectrl:starting",
+				  cache_ap_online, cache_ap_offline);
+	return 0;
+}
+early_initcall(cache_ap_register);
diff --git a/arch/x86/kernel/cpu/centaur.c b/arch/x86/kernel/cpu/centaur.c
new file mode 100644
index 0000000000..345f7d905d
--- /dev/null
+++ b/arch/x86/kernel/cpu/centaur.c
@@ -0,0 +1,251 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/sched.h>
+#include <linux/sched/clock.h>
+
+#include <asm/cpu.h>
+#include <asm/cpufeature.h>
+#include <asm/e820/api.h>
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+
+#include "cpu.h"
+
+#define ACE_PRESENT	(1 << 6)
+#define ACE_ENABLED	(1 << 7)
+#define ACE_FCR		(1 << 28)	/* MSR_VIA_FCR */
+
+#define RNG_PRESENT	(1 << 2)
+#define RNG_ENABLED	(1 << 3)
+#define RNG_ENABLE	(1 << 6)	/* MSR_VIA_RNG */
+
+static void init_c3(struct cpuinfo_x86 *c)
+{
+	u32  lo, hi;
+
+	/* Test for Centaur Extended Feature Flags presence */
+	if (cpuid_eax(0xC0000000) >= 0xC0000001) {
+		u32 tmp = cpuid_edx(0xC0000001);
+
+		/* enable ACE unit, if present and disabled */
+		if ((tmp & (ACE_PRESENT | ACE_ENABLED)) == ACE_PRESENT) {
+			rdmsr(MSR_VIA_FCR, lo, hi);
+			lo |= ACE_FCR;		/* enable ACE unit */
+			wrmsr(MSR_VIA_FCR, lo, hi);
+			pr_info("CPU: Enabled ACE h/w crypto\n");
+		}
+
+		/* enable RNG unit, if present and disabled */
+		if ((tmp & (RNG_PRESENT | RNG_ENABLED)) == RNG_PRESENT) {
+			rdmsr(MSR_VIA_RNG, lo, hi);
+			lo |= RNG_ENABLE;	/* enable RNG unit */
+			wrmsr(MSR_VIA_RNG, lo, hi);
+			pr_info("CPU: Enabled h/w RNG\n");
+		}
+
+		/* store Centaur Extended Feature Flags as
+		 * word 5 of the CPU capability bit array
+		 */
+		c->x86_capability[CPUID_C000_0001_EDX] = cpuid_edx(0xC0000001);
+	}
+#ifdef CONFIG_X86_32
+	/* Cyrix III family needs CX8 & PGE explicitly enabled. */
+	if (c->x86_model >= 6 && c->x86_model <= 13) {
+		rdmsr(MSR_VIA_FCR, lo, hi);
+		lo |= (1<<1 | 1<<7);
+		wrmsr(MSR_VIA_FCR, lo, hi);
+		set_cpu_cap(c, X86_FEATURE_CX8);
+	}
+
+	/* Before Nehemiah, the C3's had 3dNOW! */
+	if (c->x86_model >= 6 && c->x86_model < 9)
+		set_cpu_cap(c, X86_FEATURE_3DNOW);
+#endif
+	if (c->x86 == 0x6 && c->x86_model >= 0xf) {
+		c->x86_cache_alignment = c->x86_clflush_size * 2;
+		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
+	}
+
+	if (c->x86 >= 7)
+		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
+}
+
+enum {
+		ECX8		= 1<<1,
+		EIERRINT	= 1<<2,
+		DPM		= 1<<3,
+		DMCE		= 1<<4,
+		DSTPCLK		= 1<<5,
+		ELINEAR		= 1<<6,
+		DSMC		= 1<<7,
+		DTLOCK		= 1<<8,
+		EDCTLB		= 1<<8,
+		EMMX		= 1<<9,
+		DPDC		= 1<<11,
+		EBRPRED		= 1<<12,
+		DIC		= 1<<13,
+		DDC		= 1<<14,
+		DNA		= 1<<15,
+		ERETSTK		= 1<<16,
+		E2MMX		= 1<<19,
+		EAMD3D		= 1<<20,
+};
+
+static void early_init_centaur(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_X86_32
+	/* Emulate MTRRs using Centaur's MCR. */
+	if (c->x86 == 5)
+		set_cpu_cap(c, X86_FEATURE_CENTAUR_MCR);
+#endif
+	if ((c->x86 == 6 && c->x86_model >= 0xf) ||
+	    (c->x86 >= 7))
+		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
+
+#ifdef CONFIG_X86_64
+	set_cpu_cap(c, X86_FEATURE_SYSENTER32);
+#endif
+	if (c->x86_power & (1 << 8)) {
+		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
+		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
+	}
+}
+
+static void init_centaur(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_X86_32
+	char *name;
+	u32  fcr_set = 0;
+	u32  fcr_clr = 0;
+	u32  lo, hi, newlo;
+	u32  aa, bb, cc, dd;
+
+	/*
+	 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
+	 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
+	 */
+	clear_cpu_cap(c, 0*32+31);
+#endif
+	early_init_centaur(c);
+	init_intel_cacheinfo(c);
+	detect_num_cpu_cores(c);
+#ifdef CONFIG_X86_32
+	detect_ht(c);
+#endif
+
+	if (c->cpuid_level > 9) {
+		unsigned int eax = cpuid_eax(10);
+
+		/*
+		 * Check for version and the number of counters
+		 * Version(eax[7:0]) can't be 0;
+		 * Counters(eax[15:8]) should be greater than 1;
+		 */
+		if ((eax & 0xff) && (((eax >> 8) & 0xff) > 1))
+			set_cpu_cap(c, X86_FEATURE_ARCH_PERFMON);
+	}
+
+#ifdef CONFIG_X86_32
+	if (c->x86 == 5) {
+		switch (c->x86_model) {
+		case 4:
+			name = "C6";
+			fcr_set = ECX8|DSMC|EDCTLB|EMMX|ERETSTK;
+			fcr_clr = DPDC;
+			pr_notice("Disabling bugged TSC.\n");
+			clear_cpu_cap(c, X86_FEATURE_TSC);
+			break;
+		case 8:
+			switch (c->x86_stepping) {
+			default:
+			name = "2";
+				break;
+			case 7 ... 9:
+				name = "2A";
+				break;
+			case 10 ... 15:
+				name = "2B";
+				break;
+			}
+			fcr_set = ECX8|DSMC|DTLOCK|EMMX|EBRPRED|ERETSTK|
+				  E2MMX|EAMD3D;
+			fcr_clr = DPDC;
+			break;
+		case 9:
+			name = "3";
+			fcr_set = ECX8|DSMC|DTLOCK|EMMX|EBRPRED|ERETSTK|
+				  E2MMX|EAMD3D;
+			fcr_clr = DPDC;
+			break;
+		default:
+			name = "??";
+		}
+
+		rdmsr(MSR_IDT_FCR1, lo, hi);
+		newlo = (lo|fcr_set) & (~fcr_clr);
+
+		if (newlo != lo) {
+			pr_info("Centaur FCR was 0x%X now 0x%X\n",
+				lo, newlo);
+			wrmsr(MSR_IDT_FCR1, newlo, hi);
+		} else {
+			pr_info("Centaur FCR is 0x%X\n", lo);
+		}
+		/* Emulate MTRRs using Centaur's MCR. */
+		set_cpu_cap(c, X86_FEATURE_CENTAUR_MCR);
+		/* Report CX8 */
+		set_cpu_cap(c, X86_FEATURE_CX8);
+		/* Set 3DNow! on Winchip 2 and above. */
+		if (c->x86_model >= 8)
+			set_cpu_cap(c, X86_FEATURE_3DNOW);
+		/* See if we can find out some more. */
+		if (cpuid_eax(0x80000000) >= 0x80000005) {
+			/* Yes, we can. */
+			cpuid(0x80000005, &aa, &bb, &cc, &dd);
+			/* Add L1 data and code cache sizes. */
+			c->x86_cache_size = (cc>>24)+(dd>>24);
+		}
+		sprintf(c->x86_model_id, "WinChip %s", name);
+	}
+#endif
+	if (c->x86 == 6 || c->x86 >= 7)
+		init_c3(c);
+#ifdef CONFIG_X86_64
+	set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
+#endif
+
+	init_ia32_feat_ctl(c);
+}
+
+#ifdef CONFIG_X86_32
+static unsigned int
+centaur_size_cache(struct cpuinfo_x86 *c, unsigned int size)
+{
+	/* VIA C3 CPUs (670-68F) need further shifting. */
+	if ((c->x86 == 6) && ((c->x86_model == 7) || (c->x86_model == 8)))
+		size >>= 8;
+
+	/*
+	 * There's also an erratum in Nehemiah stepping 1, which
+	 * returns '65KB' instead of '64KB'
+	 *  - Note, it seems this may only be in engineering samples.
+	 */
+	if ((c->x86 == 6) && (c->x86_model == 9) &&
+				(c->x86_stepping == 1) && (size == 65))
+		size -= 1;
+	return size;
+}
+#endif
+
+static const struct cpu_dev centaur_cpu_dev = {
+	.c_vendor	= "Centaur",
+	.c_ident	= { "CentaurHauls" },
+	.c_early_init	= early_init_centaur,
+	.c_init		= init_centaur,
+#ifdef CONFIG_X86_32
+	.legacy_cache_size = centaur_size_cache,
+#endif
+	.c_x86_vendor	= X86_VENDOR_CENTAUR,
+};
+
+cpu_dev_register(centaur_cpu_dev);
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
new file mode 100644
index 0000000000..4e5ffc8b0e
--- /dev/null
+++ b/arch/x86/kernel/cpu/common.c
@@ -0,0 +1,2419 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* cpu_feature_enabled() cannot be used this early */
+#define USE_EARLY_PGTABLE_L5
+
+#include <linux/memblock.h>
+#include <linux/linkage.h>
+#include <linux/bitops.h>
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/percpu.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/delay.h>
+#include <linux/sched/mm.h>
+#include <linux/sched/clock.h>
+#include <linux/sched/task.h>
+#include <linux/sched/smt.h>
+#include <linux/init.h>
+#include <linux/kprobes.h>
+#include <linux/kgdb.h>
+#include <linux/mem_encrypt.h>
+#include <linux/smp.h>
+#include <linux/cpu.h>
+#include <linux/io.h>
+#include <linux/syscore_ops.h>
+#include <linux/pgtable.h>
+#include <linux/stackprotector.h>
+#include <linux/utsname.h>
+
+#include <asm/alternative.h>
+#include <asm/cmdline.h>
+#include <asm/perf_event.h>
+#include <asm/mmu_context.h>
+#include <asm/doublefault.h>
+#include <asm/archrandom.h>
+#include <asm/hypervisor.h>
+#include <asm/processor.h>
+#include <asm/tlbflush.h>
+#include <asm/debugreg.h>
+#include <asm/sections.h>
+#include <asm/vsyscall.h>
+#include <linux/topology.h>
+#include <linux/cpumask.h>
+#include <linux/atomic.h>
+#include <asm/proto.h>
+#include <asm/setup.h>
+#include <asm/apic.h>
+#include <asm/desc.h>
+#include <asm/fpu/api.h>
+#include <asm/mtrr.h>
+#include <asm/hwcap2.h>
+#include <linux/numa.h>
+#include <asm/numa.h>
+#include <asm/asm.h>
+#include <asm/bugs.h>
+#include <asm/cpu.h>
+#include <asm/mce.h>
+#include <asm/msr.h>
+#include <asm/cacheinfo.h>
+#include <asm/memtype.h>
+#include <asm/microcode.h>
+#include <asm/intel-family.h>
+#include <asm/cpu_device_id.h>
+#include <asm/uv/uv.h>
+#include <asm/set_memory.h>
+#include <asm/traps.h>
+#include <asm/sev.h>
+
+#include "cpu.h"
+
+u32 elf_hwcap2 __read_mostly;
+
+/* Number of siblings per CPU package */
+int smp_num_siblings = 1;
+EXPORT_SYMBOL(smp_num_siblings);
+
+/* Last level cache ID of each logical CPU */
+DEFINE_PER_CPU_READ_MOSTLY(u16, cpu_llc_id) = BAD_APICID;
+
+u16 get_llc_id(unsigned int cpu)
+{
+	return per_cpu(cpu_llc_id, cpu);
+}
+EXPORT_SYMBOL_GPL(get_llc_id);
+
+/* L2 cache ID of each logical CPU */
+DEFINE_PER_CPU_READ_MOSTLY(u16, cpu_l2c_id) = BAD_APICID;
+
+static struct ppin_info {
+	int	feature;
+	int	msr_ppin_ctl;
+	int	msr_ppin;
+} ppin_info[] = {
+	[X86_VENDOR_INTEL] = {
+		.feature = X86_FEATURE_INTEL_PPIN,
+		.msr_ppin_ctl = MSR_PPIN_CTL,
+		.msr_ppin = MSR_PPIN
+	},
+	[X86_VENDOR_AMD] = {
+		.feature = X86_FEATURE_AMD_PPIN,
+		.msr_ppin_ctl = MSR_AMD_PPIN_CTL,
+		.msr_ppin = MSR_AMD_PPIN
+	},
+};
+
+static const struct x86_cpu_id ppin_cpuids[] = {
+	X86_MATCH_FEATURE(X86_FEATURE_AMD_PPIN, &ppin_info[X86_VENDOR_AMD]),
+	X86_MATCH_FEATURE(X86_FEATURE_INTEL_PPIN, &ppin_info[X86_VENDOR_INTEL]),
+
+	/* Legacy models without CPUID enumeration */
+	X86_MATCH_INTEL_FAM6_MODEL(IVYBRIDGE_X, &ppin_info[X86_VENDOR_INTEL]),
+	X86_MATCH_INTEL_FAM6_MODEL(HASWELL_X, &ppin_info[X86_VENDOR_INTEL]),
+	X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_D, &ppin_info[X86_VENDOR_INTEL]),
+	X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_X, &ppin_info[X86_VENDOR_INTEL]),
+	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_X, &ppin_info[X86_VENDOR_INTEL]),
+	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_X, &ppin_info[X86_VENDOR_INTEL]),
+	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_D, &ppin_info[X86_VENDOR_INTEL]),
+	X86_MATCH_INTEL_FAM6_MODEL(SAPPHIRERAPIDS_X, &ppin_info[X86_VENDOR_INTEL]),
+	X86_MATCH_INTEL_FAM6_MODEL(EMERALDRAPIDS_X, &ppin_info[X86_VENDOR_INTEL]),
+	X86_MATCH_INTEL_FAM6_MODEL(XEON_PHI_KNL, &ppin_info[X86_VENDOR_INTEL]),
+	X86_MATCH_INTEL_FAM6_MODEL(XEON_PHI_KNM, &ppin_info[X86_VENDOR_INTEL]),
+
+	{}
+};
+
+static void ppin_init(struct cpuinfo_x86 *c)
+{
+	const struct x86_cpu_id *id;
+	unsigned long long val;
+	struct ppin_info *info;
+
+	id = x86_match_cpu(ppin_cpuids);
+	if (!id)
+		return;
+
+	/*
+	 * Testing the presence of the MSR is not enough. Need to check
+	 * that the PPIN_CTL allows reading of the PPIN.
+	 */
+	info = (struct ppin_info *)id->driver_data;
+
+	if (rdmsrl_safe(info->msr_ppin_ctl, &val))
+		goto clear_ppin;
+
+	if ((val & 3UL) == 1UL) {
+		/* PPIN locked in disabled mode */
+		goto clear_ppin;
+	}
+
+	/* If PPIN is disabled, try to enable */
+	if (!(val & 2UL)) {
+		wrmsrl_safe(info->msr_ppin_ctl,  val | 2UL);
+		rdmsrl_safe(info->msr_ppin_ctl, &val);
+	}
+
+	/* Is the enable bit set? */
+	if (val & 2UL) {
+		c->ppin = __rdmsr(info->msr_ppin);
+		set_cpu_cap(c, info->feature);
+		return;
+	}
+
+clear_ppin:
+	clear_cpu_cap(c, info->feature);
+}
+
+static void default_init(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_X86_64
+	cpu_detect_cache_sizes(c);
+#else
+	/* Not much we can do here... */
+	/* Check if at least it has cpuid */
+	if (c->cpuid_level == -1) {
+		/* No cpuid. It must be an ancient CPU */
+		if (c->x86 == 4)
+			strcpy(c->x86_model_id, "486");
+		else if (c->x86 == 3)
+			strcpy(c->x86_model_id, "386");
+	}
+#endif
+}
+
+static const struct cpu_dev default_cpu = {
+	.c_init		= default_init,
+	.c_vendor	= "Unknown",
+	.c_x86_vendor	= X86_VENDOR_UNKNOWN,
+};
+
+static const struct cpu_dev *this_cpu = &default_cpu;
+
+DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
+#ifdef CONFIG_X86_64
+	/*
+	 * We need valid kernel segments for data and code in long mode too
+	 * IRET will check the segment types  kkeil 2000/10/28
+	 * Also sysret mandates a special GDT layout
+	 *
+	 * TLS descriptors are currently at a different place compared to i386.
+	 * Hopefully nobody expects them at a fixed place (Wine?)
+	 */
+	[GDT_ENTRY_KERNEL32_CS]		= GDT_ENTRY_INIT(0xc09b, 0, 0xfffff),
+	[GDT_ENTRY_KERNEL_CS]		= GDT_ENTRY_INIT(0xa09b, 0, 0xfffff),
+	[GDT_ENTRY_KERNEL_DS]		= GDT_ENTRY_INIT(0xc093, 0, 0xfffff),
+	[GDT_ENTRY_DEFAULT_USER32_CS]	= GDT_ENTRY_INIT(0xc0fb, 0, 0xfffff),
+	[GDT_ENTRY_DEFAULT_USER_DS]	= GDT_ENTRY_INIT(0xc0f3, 0, 0xfffff),
+	[GDT_ENTRY_DEFAULT_USER_CS]	= GDT_ENTRY_INIT(0xa0fb, 0, 0xfffff),
+#else
+	[GDT_ENTRY_KERNEL_CS]		= GDT_ENTRY_INIT(0xc09a, 0, 0xfffff),
+	[GDT_ENTRY_KERNEL_DS]		= GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
+	[GDT_ENTRY_DEFAULT_USER_CS]	= GDT_ENTRY_INIT(0xc0fa, 0, 0xfffff),
+	[GDT_ENTRY_DEFAULT_USER_DS]	= GDT_ENTRY_INIT(0xc0f2, 0, 0xfffff),
+	/*
+	 * Segments used for calling PnP BIOS have byte granularity.
+	 * They code segments and data segments have fixed 64k limits,
+	 * the transfer segment sizes are set at run time.
+	 */
+	/* 32-bit code */
+	[GDT_ENTRY_PNPBIOS_CS32]	= GDT_ENTRY_INIT(0x409a, 0, 0xffff),
+	/* 16-bit code */
+	[GDT_ENTRY_PNPBIOS_CS16]	= GDT_ENTRY_INIT(0x009a, 0, 0xffff),
+	/* 16-bit data */
+	[GDT_ENTRY_PNPBIOS_DS]		= GDT_ENTRY_INIT(0x0092, 0, 0xffff),
+	/* 16-bit data */
+	[GDT_ENTRY_PNPBIOS_TS1]		= GDT_ENTRY_INIT(0x0092, 0, 0),
+	/* 16-bit data */
+	[GDT_ENTRY_PNPBIOS_TS2]		= GDT_ENTRY_INIT(0x0092, 0, 0),
+	/*
+	 * The APM segments have byte granularity and their bases
+	 * are set at run time.  All have 64k limits.
+	 */
+	/* 32-bit code */
+	[GDT_ENTRY_APMBIOS_BASE]	= GDT_ENTRY_INIT(0x409a, 0, 0xffff),
+	/* 16-bit code */
+	[GDT_ENTRY_APMBIOS_BASE+1]	= GDT_ENTRY_INIT(0x009a, 0, 0xffff),
+	/* data */
+	[GDT_ENTRY_APMBIOS_BASE+2]	= GDT_ENTRY_INIT(0x4092, 0, 0xffff),
+
+	[GDT_ENTRY_ESPFIX_SS]		= GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
+	[GDT_ENTRY_PERCPU]		= GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
+#endif
+} };
+EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);
+
+#ifdef CONFIG_X86_64
+static int __init x86_nopcid_setup(char *s)
+{
+	/* nopcid doesn't accept parameters */
+	if (s)
+		return -EINVAL;
+
+	/* do not emit a message if the feature is not present */
+	if (!boot_cpu_has(X86_FEATURE_PCID))
+		return 0;
+
+	setup_clear_cpu_cap(X86_FEATURE_PCID);
+	pr_info("nopcid: PCID feature disabled\n");
+	return 0;
+}
+early_param("nopcid", x86_nopcid_setup);
+#endif
+
+static int __init x86_noinvpcid_setup(char *s)
+{
+	/* noinvpcid doesn't accept parameters */
+	if (s)
+		return -EINVAL;
+
+	/* do not emit a message if the feature is not present */
+	if (!boot_cpu_has(X86_FEATURE_INVPCID))
+		return 0;
+
+	setup_clear_cpu_cap(X86_FEATURE_INVPCID);
+	pr_info("noinvpcid: INVPCID feature disabled\n");
+	return 0;
+}
+early_param("noinvpcid", x86_noinvpcid_setup);
+
+#ifdef CONFIG_X86_32
+static int cachesize_override = -1;
+static int disable_x86_serial_nr = 1;
+
+static int __init cachesize_setup(char *str)
+{
+	get_option(&str, &cachesize_override);
+	return 1;
+}
+__setup("cachesize=", cachesize_setup);
+
+/* Standard macro to see if a specific flag is changeable */
+static inline int flag_is_changeable_p(u32 flag)
+{
+	u32 f1, f2;
+
+	/*
+	 * Cyrix and IDT cpus allow disabling of CPUID
+	 * so the code below may return different results
+	 * when it is executed before and after enabling
+	 * the CPUID. Add "volatile" to not allow gcc to
+	 * optimize the subsequent calls to this function.
+	 */
+	asm volatile ("pushfl		\n\t"
+		      "pushfl		\n\t"
+		      "popl %0		\n\t"
+		      "movl %0, %1	\n\t"
+		      "xorl %2, %0	\n\t"
+		      "pushl %0		\n\t"
+		      "popfl		\n\t"
+		      "pushfl		\n\t"
+		      "popl %0		\n\t"
+		      "popfl		\n\t"
+
+		      : "=&r" (f1), "=&r" (f2)
+		      : "ir" (flag));
+
+	return ((f1^f2) & flag) != 0;
+}
+
+/* Probe for the CPUID instruction */
+int have_cpuid_p(void)
+{
+	return flag_is_changeable_p(X86_EFLAGS_ID);
+}
+
+static void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
+{
+	unsigned long lo, hi;
+
+	if (!cpu_has(c, X86_FEATURE_PN) || !disable_x86_serial_nr)
+		return;
+
+	/* Disable processor serial number: */
+
+	rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
+	lo |= 0x200000;
+	wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
+
+	pr_notice("CPU serial number disabled.\n");
+	clear_cpu_cap(c, X86_FEATURE_PN);
+
+	/* Disabling the serial number may affect the cpuid level */
+	c->cpuid_level = cpuid_eax(0);
+}
+
+static int __init x86_serial_nr_setup(char *s)
+{
+	disable_x86_serial_nr = 0;
+	return 1;
+}
+__setup("serialnumber", x86_serial_nr_setup);
+#else
+static inline int flag_is_changeable_p(u32 flag)
+{
+	return 1;
+}
+static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
+{
+}
+#endif
+
+static __always_inline void setup_smep(struct cpuinfo_x86 *c)
+{
+	if (cpu_has(c, X86_FEATURE_SMEP))
+		cr4_set_bits(X86_CR4_SMEP);
+}
+
+static __always_inline void setup_smap(struct cpuinfo_x86 *c)
+{
+	unsigned long eflags = native_save_fl();
+
+	/* This should have been cleared long ago */
+	BUG_ON(eflags & X86_EFLAGS_AC);
+
+	if (cpu_has(c, X86_FEATURE_SMAP))
+		cr4_set_bits(X86_CR4_SMAP);
+}
+
+static __always_inline void setup_umip(struct cpuinfo_x86 *c)
+{
+	/* Check the boot processor, plus build option for UMIP. */
+	if (!cpu_feature_enabled(X86_FEATURE_UMIP))
+		goto out;
+
+	/* Check the current processor's cpuid bits. */
+	if (!cpu_has(c, X86_FEATURE_UMIP))
+		goto out;
+
+	cr4_set_bits(X86_CR4_UMIP);
+
+	pr_info_once("x86/cpu: User Mode Instruction Prevention (UMIP) activated\n");
+
+	return;
+
+out:
+	/*
+	 * Make sure UMIP is disabled in case it was enabled in a
+	 * previous boot (e.g., via kexec).
+	 */
+	cr4_clear_bits(X86_CR4_UMIP);
+}
+
+/* These bits should not change their value after CPU init is finished. */
+static const unsigned long cr4_pinned_mask =
+	X86_CR4_SMEP | X86_CR4_SMAP | X86_CR4_UMIP |
+	X86_CR4_FSGSBASE | X86_CR4_CET;
+static DEFINE_STATIC_KEY_FALSE_RO(cr_pinning);
+static unsigned long cr4_pinned_bits __ro_after_init;
+
+void native_write_cr0(unsigned long val)
+{
+	unsigned long bits_missing = 0;
+
+set_register:
+	asm volatile("mov %0,%%cr0": "+r" (val) : : "memory");
+
+	if (static_branch_likely(&cr_pinning)) {
+		if (unlikely((val & X86_CR0_WP) != X86_CR0_WP)) {
+			bits_missing = X86_CR0_WP;
+			val |= bits_missing;
+			goto set_register;
+		}
+		/* Warn after we've set the missing bits. */
+		WARN_ONCE(bits_missing, "CR0 WP bit went missing!?\n");
+	}
+}
+EXPORT_SYMBOL(native_write_cr0);
+
+void __no_profile native_write_cr4(unsigned long val)
+{
+	unsigned long bits_changed = 0;
+
+set_register:
+	asm volatile("mov %0,%%cr4": "+r" (val) : : "memory");
+
+	if (static_branch_likely(&cr_pinning)) {
+		if (unlikely((val & cr4_pinned_mask) != cr4_pinned_bits)) {
+			bits_changed = (val & cr4_pinned_mask) ^ cr4_pinned_bits;
+			val = (val & ~cr4_pinned_mask) | cr4_pinned_bits;
+			goto set_register;
+		}
+		/* Warn after we've corrected the changed bits. */
+		WARN_ONCE(bits_changed, "pinned CR4 bits changed: 0x%lx!?\n",
+			  bits_changed);
+	}
+}
+#if IS_MODULE(CONFIG_LKDTM)
+EXPORT_SYMBOL_GPL(native_write_cr4);
+#endif
+
+void cr4_update_irqsoff(unsigned long set, unsigned long clear)
+{
+	unsigned long newval, cr4 = this_cpu_read(cpu_tlbstate.cr4);
+
+	lockdep_assert_irqs_disabled();
+
+	newval = (cr4 & ~clear) | set;
+	if (newval != cr4) {
+		this_cpu_write(cpu_tlbstate.cr4, newval);
+		__write_cr4(newval);
+	}
+}
+EXPORT_SYMBOL(cr4_update_irqsoff);
+
+/* Read the CR4 shadow. */
+unsigned long cr4_read_shadow(void)
+{
+	return this_cpu_read(cpu_tlbstate.cr4);
+}
+EXPORT_SYMBOL_GPL(cr4_read_shadow);
+
+void cr4_init(void)
+{
+	unsigned long cr4 = __read_cr4();
+
+	if (boot_cpu_has(X86_FEATURE_PCID))
+		cr4 |= X86_CR4_PCIDE;
+	if (static_branch_likely(&cr_pinning))
+		cr4 = (cr4 & ~cr4_pinned_mask) | cr4_pinned_bits;
+
+	__write_cr4(cr4);
+
+	/* Initialize cr4 shadow for this CPU. */
+	this_cpu_write(cpu_tlbstate.cr4, cr4);
+}
+
+/*
+ * Once CPU feature detection is finished (and boot params have been
+ * parsed), record any of the sensitive CR bits that are set, and
+ * enable CR pinning.
+ */
+static void __init setup_cr_pinning(void)
+{
+	cr4_pinned_bits = this_cpu_read(cpu_tlbstate.cr4) & cr4_pinned_mask;
+	static_key_enable(&cr_pinning.key);
+}
+
+static __init int x86_nofsgsbase_setup(char *arg)
+{
+	/* Require an exact match without trailing characters. */
+	if (strlen(arg))
+		return 0;
+
+	/* Do not emit a message if the feature is not present. */
+	if (!boot_cpu_has(X86_FEATURE_FSGSBASE))
+		return 1;
+
+	setup_clear_cpu_cap(X86_FEATURE_FSGSBASE);
+	pr_info("FSGSBASE disabled via kernel command line\n");
+	return 1;
+}
+__setup("nofsgsbase", x86_nofsgsbase_setup);
+
+/*
+ * Protection Keys are not available in 32-bit mode.
+ */
+static bool pku_disabled;
+
+static __always_inline void setup_pku(struct cpuinfo_x86 *c)
+{
+	if (c == &boot_cpu_data) {
+		if (pku_disabled || !cpu_feature_enabled(X86_FEATURE_PKU))
+			return;
+		/*
+		 * Setting CR4.PKE will cause the X86_FEATURE_OSPKE cpuid
+		 * bit to be set.  Enforce it.
+		 */
+		setup_force_cpu_cap(X86_FEATURE_OSPKE);
+
+	} else if (!cpu_feature_enabled(X86_FEATURE_OSPKE)) {
+		return;
+	}
+
+	cr4_set_bits(X86_CR4_PKE);
+	/* Load the default PKRU value */
+	pkru_write_default();
+}
+
+#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
+static __init int setup_disable_pku(char *arg)
+{
+	/*
+	 * Do not clear the X86_FEATURE_PKU bit.  All of the
+	 * runtime checks are against OSPKE so clearing the
+	 * bit does nothing.
+	 *
+	 * This way, we will see "pku" in cpuinfo, but not
+	 * "ospke", which is exactly what we want.  It shows
+	 * that the CPU has PKU, but the OS has not enabled it.
+	 * This happens to be exactly how a system would look
+	 * if we disabled the config option.
+	 */
+	pr_info("x86: 'nopku' specified, disabling Memory Protection Keys\n");
+	pku_disabled = true;
+	return 1;
+}
+__setup("nopku", setup_disable_pku);
+#endif
+
+#ifdef CONFIG_X86_KERNEL_IBT
+
+__noendbr u64 ibt_save(bool disable)
+{
+	u64 msr = 0;
+
+	if (cpu_feature_enabled(X86_FEATURE_IBT)) {
+		rdmsrl(MSR_IA32_S_CET, msr);
+		if (disable)
+			wrmsrl(MSR_IA32_S_CET, msr & ~CET_ENDBR_EN);
+	}
+
+	return msr;
+}
+
+__noendbr void ibt_restore(u64 save)
+{
+	u64 msr;
+
+	if (cpu_feature_enabled(X86_FEATURE_IBT)) {
+		rdmsrl(MSR_IA32_S_CET, msr);
+		msr &= ~CET_ENDBR_EN;
+		msr |= (save & CET_ENDBR_EN);
+		wrmsrl(MSR_IA32_S_CET, msr);
+	}
+}
+
+#endif
+
+static __always_inline void setup_cet(struct cpuinfo_x86 *c)
+{
+	bool user_shstk, kernel_ibt;
+
+	if (!IS_ENABLED(CONFIG_X86_CET))
+		return;
+
+	kernel_ibt = HAS_KERNEL_IBT && cpu_feature_enabled(X86_FEATURE_IBT);
+	user_shstk = cpu_feature_enabled(X86_FEATURE_SHSTK) &&
+		     IS_ENABLED(CONFIG_X86_USER_SHADOW_STACK);
+
+	if (!kernel_ibt && !user_shstk)
+		return;
+
+	if (user_shstk)
+		set_cpu_cap(c, X86_FEATURE_USER_SHSTK);
+
+	if (kernel_ibt)
+		wrmsrl(MSR_IA32_S_CET, CET_ENDBR_EN);
+	else
+		wrmsrl(MSR_IA32_S_CET, 0);
+
+	cr4_set_bits(X86_CR4_CET);
+
+	if (kernel_ibt && ibt_selftest()) {
+		pr_err("IBT selftest: Failed!\n");
+		wrmsrl(MSR_IA32_S_CET, 0);
+		setup_clear_cpu_cap(X86_FEATURE_IBT);
+	}
+}
+
+__noendbr void cet_disable(void)
+{
+	if (!(cpu_feature_enabled(X86_FEATURE_IBT) ||
+	      cpu_feature_enabled(X86_FEATURE_SHSTK)))
+		return;
+
+	wrmsrl(MSR_IA32_S_CET, 0);
+	wrmsrl(MSR_IA32_U_CET, 0);
+}
+
+/*
+ * Some CPU features depend on higher CPUID levels, which may not always
+ * be available due to CPUID level capping or broken virtualization
+ * software.  Add those features to this table to auto-disable them.
+ */
+struct cpuid_dependent_feature {
+	u32 feature;
+	u32 level;
+};
+
+static const struct cpuid_dependent_feature
+cpuid_dependent_features[] = {
+	{ X86_FEATURE_MWAIT,		0x00000005 },
+	{ X86_FEATURE_DCA,		0x00000009 },
+	{ X86_FEATURE_XSAVE,		0x0000000d },
+	{ 0, 0 }
+};
+
+static void filter_cpuid_features(struct cpuinfo_x86 *c, bool warn)
+{
+	const struct cpuid_dependent_feature *df;
+
+	for (df = cpuid_dependent_features; df->feature; df++) {
+
+		if (!cpu_has(c, df->feature))
+			continue;
+		/*
+		 * Note: cpuid_level is set to -1 if unavailable, but
+		 * extended_extended_level is set to 0 if unavailable
+		 * and the legitimate extended levels are all negative
+		 * when signed; hence the weird messing around with
+		 * signs here...
+		 */
+		if (!((s32)df->level < 0 ?
+		     (u32)df->level > (u32)c->extended_cpuid_level :
+		     (s32)df->level > (s32)c->cpuid_level))
+			continue;
+
+		clear_cpu_cap(c, df->feature);
+		if (!warn)
+			continue;
+
+		pr_warn("CPU: CPU feature " X86_CAP_FMT " disabled, no CPUID level 0x%x\n",
+			x86_cap_flag(df->feature), df->level);
+	}
+}
+
+/*
+ * Naming convention should be: <Name> [(<Codename>)]
+ * This table only is used unless init_<vendor>() below doesn't set it;
+ * in particular, if CPUID levels 0x80000002..4 are supported, this
+ * isn't used
+ */
+
+/* Look up CPU names by table lookup. */
+static const char *table_lookup_model(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_X86_32
+	const struct legacy_cpu_model_info *info;
+
+	if (c->x86_model >= 16)
+		return NULL;	/* Range check */
+
+	if (!this_cpu)
+		return NULL;
+
+	info = this_cpu->legacy_models;
+
+	while (info->family) {
+		if (info->family == c->x86)
+			return info->model_names[c->x86_model];
+		info++;
+	}
+#endif
+	return NULL;		/* Not found */
+}
+
+/* Aligned to unsigned long to avoid split lock in atomic bitmap ops */
+__u32 cpu_caps_cleared[NCAPINTS + NBUGINTS] __aligned(sizeof(unsigned long));
+__u32 cpu_caps_set[NCAPINTS + NBUGINTS] __aligned(sizeof(unsigned long));
+
+#ifdef CONFIG_X86_32
+/* The 32-bit entry code needs to find cpu_entry_area. */
+DEFINE_PER_CPU(struct cpu_entry_area *, cpu_entry_area);
+#endif
+
+/* Load the original GDT from the per-cpu structure */
+void load_direct_gdt(int cpu)
+{
+	struct desc_ptr gdt_descr;
+
+	gdt_descr.address = (long)get_cpu_gdt_rw(cpu);
+	gdt_descr.size = GDT_SIZE - 1;
+	load_gdt(&gdt_descr);
+}
+EXPORT_SYMBOL_GPL(load_direct_gdt);
+
+/* Load a fixmap remapping of the per-cpu GDT */
+void load_fixmap_gdt(int cpu)
+{
+	struct desc_ptr gdt_descr;
+
+	gdt_descr.address = (long)get_cpu_gdt_ro(cpu);
+	gdt_descr.size = GDT_SIZE - 1;
+	load_gdt(&gdt_descr);
+}
+EXPORT_SYMBOL_GPL(load_fixmap_gdt);
+
+/**
+ * switch_gdt_and_percpu_base - Switch to direct GDT and runtime per CPU base
+ * @cpu:	The CPU number for which this is invoked
+ *
+ * Invoked during early boot to switch from early GDT and early per CPU to
+ * the direct GDT and the runtime per CPU area. On 32-bit the percpu base
+ * switch is implicit by loading the direct GDT. On 64bit this requires
+ * to update GSBASE.
+ */
+void __init switch_gdt_and_percpu_base(int cpu)
+{
+	load_direct_gdt(cpu);
+
+#ifdef CONFIG_X86_64
+	/*
+	 * No need to load %gs. It is already correct.
+	 *
+	 * Writing %gs on 64bit would zero GSBASE which would make any per
+	 * CPU operation up to the point of the wrmsrl() fault.
+	 *
+	 * Set GSBASE to the new offset. Until the wrmsrl() happens the
+	 * early mapping is still valid. That means the GSBASE update will
+	 * lose any prior per CPU data which was not copied over in
+	 * setup_per_cpu_areas().
+	 *
+	 * This works even with stackprotector enabled because the
+	 * per CPU stack canary is 0 in both per CPU areas.
+	 */
+	wrmsrl(MSR_GS_BASE, cpu_kernelmode_gs_base(cpu));
+#else
+	/*
+	 * %fs is already set to __KERNEL_PERCPU, but after switching GDT
+	 * it is required to load FS again so that the 'hidden' part is
+	 * updated from the new GDT. Up to this point the early per CPU
+	 * translation is active. Any content of the early per CPU data
+	 * which was not copied over in setup_per_cpu_areas() is lost.
+	 */
+	loadsegment(fs, __KERNEL_PERCPU);
+#endif
+}
+
+static const struct cpu_dev *cpu_devs[X86_VENDOR_NUM] = {};
+
+static void get_model_name(struct cpuinfo_x86 *c)
+{
+	unsigned int *v;
+	char *p, *q, *s;
+
+	if (c->extended_cpuid_level < 0x80000004)
+		return;
+
+	v = (unsigned int *)c->x86_model_id;
+	cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
+	cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
+	cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
+	c->x86_model_id[48] = 0;
+
+	/* Trim whitespace */
+	p = q = s = &c->x86_model_id[0];
+
+	while (*p == ' ')
+		p++;
+
+	while (*p) {
+		/* Note the last non-whitespace index */
+		if (!isspace(*p))
+			s = q;
+
+		*q++ = *p++;
+	}
+
+	*(s + 1) = '\0';
+}
+
+void detect_num_cpu_cores(struct cpuinfo_x86 *c)
+{
+	unsigned int eax, ebx, ecx, edx;
+
+	c->x86_max_cores = 1;
+	if (!IS_ENABLED(CONFIG_SMP) || c->cpuid_level < 4)
+		return;
+
+	cpuid_count(4, 0, &eax, &ebx, &ecx, &edx);
+	if (eax & 0x1f)
+		c->x86_max_cores = (eax >> 26) + 1;
+}
+
+void cpu_detect_cache_sizes(struct cpuinfo_x86 *c)
+{
+	unsigned int n, dummy, ebx, ecx, edx, l2size;
+
+	n = c->extended_cpuid_level;
+
+	if (n >= 0x80000005) {
+		cpuid(0x80000005, &dummy, &ebx, &ecx, &edx);
+		c->x86_cache_size = (ecx>>24) + (edx>>24);
+#ifdef CONFIG_X86_64
+		/* On K8 L1 TLB is inclusive, so don't count it */
+		c->x86_tlbsize = 0;
+#endif
+	}
+
+	if (n < 0x80000006)	/* Some chips just has a large L1. */
+		return;
+
+	cpuid(0x80000006, &dummy, &ebx, &ecx, &edx);
+	l2size = ecx >> 16;
+
+#ifdef CONFIG_X86_64
+	c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff);
+#else
+	/* do processor-specific cache resizing */
+	if (this_cpu->legacy_cache_size)
+		l2size = this_cpu->legacy_cache_size(c, l2size);
+
+	/* Allow user to override all this if necessary. */
+	if (cachesize_override != -1)
+		l2size = cachesize_override;
+
+	if (l2size == 0)
+		return;		/* Again, no L2 cache is possible */
+#endif
+
+	c->x86_cache_size = l2size;
+}
+
+u16 __read_mostly tlb_lli_4k[NR_INFO];
+u16 __read_mostly tlb_lli_2m[NR_INFO];
+u16 __read_mostly tlb_lli_4m[NR_INFO];
+u16 __read_mostly tlb_lld_4k[NR_INFO];
+u16 __read_mostly tlb_lld_2m[NR_INFO];
+u16 __read_mostly tlb_lld_4m[NR_INFO];
+u16 __read_mostly tlb_lld_1g[NR_INFO];
+
+static void cpu_detect_tlb(struct cpuinfo_x86 *c)
+{
+	if (this_cpu->c_detect_tlb)
+		this_cpu->c_detect_tlb(c);
+
+	pr_info("Last level iTLB entries: 4KB %d, 2MB %d, 4MB %d\n",
+		tlb_lli_4k[ENTRIES], tlb_lli_2m[ENTRIES],
+		tlb_lli_4m[ENTRIES]);
+
+	pr_info("Last level dTLB entries: 4KB %d, 2MB %d, 4MB %d, 1GB %d\n",
+		tlb_lld_4k[ENTRIES], tlb_lld_2m[ENTRIES],
+		tlb_lld_4m[ENTRIES], tlb_lld_1g[ENTRIES]);
+}
+
+int detect_ht_early(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_SMP
+	u32 eax, ebx, ecx, edx;
+
+	if (!cpu_has(c, X86_FEATURE_HT))
+		return -1;
+
+	if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
+		return -1;
+
+	if (cpu_has(c, X86_FEATURE_XTOPOLOGY))
+		return -1;
+
+	cpuid(1, &eax, &ebx, &ecx, &edx);
+
+	smp_num_siblings = (ebx & 0xff0000) >> 16;
+	if (smp_num_siblings == 1)
+		pr_info_once("CPU0: Hyper-Threading is disabled\n");
+#endif
+	return 0;
+}
+
+void detect_ht(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_SMP
+	int index_msb, core_bits;
+
+	if (detect_ht_early(c) < 0)
+		return;
+
+	index_msb = get_count_order(smp_num_siblings);
+	c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, index_msb);
+
+	smp_num_siblings = smp_num_siblings / c->x86_max_cores;
+
+	index_msb = get_count_order(smp_num_siblings);
+
+	core_bits = get_count_order(c->x86_max_cores);
+
+	c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, index_msb) &
+				       ((1 << core_bits) - 1);
+#endif
+}
+
+static void get_cpu_vendor(struct cpuinfo_x86 *c)
+{
+	char *v = c->x86_vendor_id;
+	int i;
+
+	for (i = 0; i < X86_VENDOR_NUM; i++) {
+		if (!cpu_devs[i])
+			break;
+
+		if (!strcmp(v, cpu_devs[i]->c_ident[0]) ||
+		    (cpu_devs[i]->c_ident[1] &&
+		     !strcmp(v, cpu_devs[i]->c_ident[1]))) {
+
+			this_cpu = cpu_devs[i];
+			c->x86_vendor = this_cpu->c_x86_vendor;
+			return;
+		}
+	}
+
+	pr_err_once("CPU: vendor_id '%s' unknown, using generic init.\n" \
+		    "CPU: Your system may be unstable.\n", v);
+
+	c->x86_vendor = X86_VENDOR_UNKNOWN;
+	this_cpu = &default_cpu;
+}
+
+void cpu_detect(struct cpuinfo_x86 *c)
+{
+	/* Get vendor name */
+	cpuid(0x00000000, (unsigned int *)&c->cpuid_level,
+	      (unsigned int *)&c->x86_vendor_id[0],
+	      (unsigned int *)&c->x86_vendor_id[8],
+	      (unsigned int *)&c->x86_vendor_id[4]);
+
+	c->x86 = 4;
+	/* Intel-defined flags: level 0x00000001 */
+	if (c->cpuid_level >= 0x00000001) {
+		u32 junk, tfms, cap0, misc;
+
+		cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
+		c->x86		= x86_family(tfms);
+		c->x86_model	= x86_model(tfms);
+		c->x86_stepping	= x86_stepping(tfms);
+
+		if (cap0 & (1<<19)) {
+			c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
+			c->x86_cache_alignment = c->x86_clflush_size;
+		}
+	}
+}
+
+static void apply_forced_caps(struct cpuinfo_x86 *c)
+{
+	int i;
+
+	for (i = 0; i < NCAPINTS + NBUGINTS; i++) {
+		c->x86_capability[i] &= ~cpu_caps_cleared[i];
+		c->x86_capability[i] |= cpu_caps_set[i];
+	}
+}
+
+static void init_speculation_control(struct cpuinfo_x86 *c)
+{
+	/*
+	 * The Intel SPEC_CTRL CPUID bit implies IBRS and IBPB support,
+	 * and they also have a different bit for STIBP support. Also,
+	 * a hypervisor might have set the individual AMD bits even on
+	 * Intel CPUs, for finer-grained selection of what's available.
+	 */
+	if (cpu_has(c, X86_FEATURE_SPEC_CTRL)) {
+		set_cpu_cap(c, X86_FEATURE_IBRS);
+		set_cpu_cap(c, X86_FEATURE_IBPB);
+		set_cpu_cap(c, X86_FEATURE_MSR_SPEC_CTRL);
+	}
+
+	if (cpu_has(c, X86_FEATURE_INTEL_STIBP))
+		set_cpu_cap(c, X86_FEATURE_STIBP);
+
+	if (cpu_has(c, X86_FEATURE_SPEC_CTRL_SSBD) ||
+	    cpu_has(c, X86_FEATURE_VIRT_SSBD))
+		set_cpu_cap(c, X86_FEATURE_SSBD);
+
+	if (cpu_has(c, X86_FEATURE_AMD_IBRS)) {
+		set_cpu_cap(c, X86_FEATURE_IBRS);
+		set_cpu_cap(c, X86_FEATURE_MSR_SPEC_CTRL);
+	}
+
+	if (cpu_has(c, X86_FEATURE_AMD_IBPB))
+		set_cpu_cap(c, X86_FEATURE_IBPB);
+
+	if (cpu_has(c, X86_FEATURE_AMD_STIBP)) {
+		set_cpu_cap(c, X86_FEATURE_STIBP);
+		set_cpu_cap(c, X86_FEATURE_MSR_SPEC_CTRL);
+	}
+
+	if (cpu_has(c, X86_FEATURE_AMD_SSBD)) {
+		set_cpu_cap(c, X86_FEATURE_SSBD);
+		set_cpu_cap(c, X86_FEATURE_MSR_SPEC_CTRL);
+		clear_cpu_cap(c, X86_FEATURE_VIRT_SSBD);
+	}
+}
+
+void get_cpu_cap(struct cpuinfo_x86 *c)
+{
+	u32 eax, ebx, ecx, edx;
+
+	/* Intel-defined flags: level 0x00000001 */
+	if (c->cpuid_level >= 0x00000001) {
+		cpuid(0x00000001, &eax, &ebx, &ecx, &edx);
+
+		c->x86_capability[CPUID_1_ECX] = ecx;
+		c->x86_capability[CPUID_1_EDX] = edx;
+	}
+
+	/* Thermal and Power Management Leaf: level 0x00000006 (eax) */
+	if (c->cpuid_level >= 0x00000006)
+		c->x86_capability[CPUID_6_EAX] = cpuid_eax(0x00000006);
+
+	/* Additional Intel-defined flags: level 0x00000007 */
+	if (c->cpuid_level >= 0x00000007) {
+		cpuid_count(0x00000007, 0, &eax, &ebx, &ecx, &edx);
+		c->x86_capability[CPUID_7_0_EBX] = ebx;
+		c->x86_capability[CPUID_7_ECX] = ecx;
+		c->x86_capability[CPUID_7_EDX] = edx;
+
+		/* Check valid sub-leaf index before accessing it */
+		if (eax >= 1) {
+			cpuid_count(0x00000007, 1, &eax, &ebx, &ecx, &edx);
+			c->x86_capability[CPUID_7_1_EAX] = eax;
+		}
+	}
+
+	/* Extended state features: level 0x0000000d */
+	if (c->cpuid_level >= 0x0000000d) {
+		cpuid_count(0x0000000d, 1, &eax, &ebx, &ecx, &edx);
+
+		c->x86_capability[CPUID_D_1_EAX] = eax;
+	}
+
+	/* AMD-defined flags: level 0x80000001 */
+	eax = cpuid_eax(0x80000000);
+	c->extended_cpuid_level = eax;
+
+	if ((eax & 0xffff0000) == 0x80000000) {
+		if (eax >= 0x80000001) {
+			cpuid(0x80000001, &eax, &ebx, &ecx, &edx);
+
+			c->x86_capability[CPUID_8000_0001_ECX] = ecx;
+			c->x86_capability[CPUID_8000_0001_EDX] = edx;
+		}
+	}
+
+	if (c->extended_cpuid_level >= 0x80000007) {
+		cpuid(0x80000007, &eax, &ebx, &ecx, &edx);
+
+		c->x86_capability[CPUID_8000_0007_EBX] = ebx;
+		c->x86_power = edx;
+	}
+
+	if (c->extended_cpuid_level >= 0x80000008) {
+		cpuid(0x80000008, &eax, &ebx, &ecx, &edx);
+		c->x86_capability[CPUID_8000_0008_EBX] = ebx;
+	}
+
+	if (c->extended_cpuid_level >= 0x8000000a)
+		c->x86_capability[CPUID_8000_000A_EDX] = cpuid_edx(0x8000000a);
+
+	if (c->extended_cpuid_level >= 0x8000001f)
+		c->x86_capability[CPUID_8000_001F_EAX] = cpuid_eax(0x8000001f);
+
+	if (c->extended_cpuid_level >= 0x80000021)
+		c->x86_capability[CPUID_8000_0021_EAX] = cpuid_eax(0x80000021);
+
+	init_scattered_cpuid_features(c);
+	init_speculation_control(c);
+
+	/*
+	 * Clear/Set all flags overridden by options, after probe.
+	 * This needs to happen each time we re-probe, which may happen
+	 * several times during CPU initialization.
+	 */
+	apply_forced_caps(c);
+}
+
+void get_cpu_address_sizes(struct cpuinfo_x86 *c)
+{
+	u32 eax, ebx, ecx, edx;
+
+	if (c->extended_cpuid_level >= 0x80000008) {
+		cpuid(0x80000008, &eax, &ebx, &ecx, &edx);
+
+		c->x86_virt_bits = (eax >> 8) & 0xff;
+		c->x86_phys_bits = eax & 0xff;
+	}
+#ifdef CONFIG_X86_32
+	else if (cpu_has(c, X86_FEATURE_PAE) || cpu_has(c, X86_FEATURE_PSE36))
+		c->x86_phys_bits = 36;
+#endif
+	c->x86_cache_bits = c->x86_phys_bits;
+}
+
+static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_X86_32
+	int i;
+
+	/*
+	 * First of all, decide if this is a 486 or higher
+	 * It's a 486 if we can modify the AC flag
+	 */
+	if (flag_is_changeable_p(X86_EFLAGS_AC))
+		c->x86 = 4;
+	else
+		c->x86 = 3;
+
+	for (i = 0; i < X86_VENDOR_NUM; i++)
+		if (cpu_devs[i] && cpu_devs[i]->c_identify) {
+			c->x86_vendor_id[0] = 0;
+			cpu_devs[i]->c_identify(c);
+			if (c->x86_vendor_id[0]) {
+				get_cpu_vendor(c);
+				break;
+			}
+		}
+#endif
+}
+
+#define NO_SPECULATION		BIT(0)
+#define NO_MELTDOWN		BIT(1)
+#define NO_SSB			BIT(2)
+#define NO_L1TF			BIT(3)
+#define NO_MDS			BIT(4)
+#define MSBDS_ONLY		BIT(5)
+#define NO_SWAPGS		BIT(6)
+#define NO_ITLB_MULTIHIT	BIT(7)
+#define NO_SPECTRE_V2		BIT(8)
+#define NO_MMIO			BIT(9)
+#define NO_EIBRS_PBRSB		BIT(10)
+
+#define VULNWL(vendor, family, model, whitelist)	\
+	X86_MATCH_VENDOR_FAM_MODEL(vendor, family, model, whitelist)
+
+#define VULNWL_INTEL(model, whitelist)		\
+	VULNWL(INTEL, 6, INTEL_FAM6_##model, whitelist)
+
+#define VULNWL_AMD(family, whitelist)		\
+	VULNWL(AMD, family, X86_MODEL_ANY, whitelist)
+
+#define VULNWL_HYGON(family, whitelist)		\
+	VULNWL(HYGON, family, X86_MODEL_ANY, whitelist)
+
+static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
+	VULNWL(ANY,	4, X86_MODEL_ANY,	NO_SPECULATION),
+	VULNWL(CENTAUR,	5, X86_MODEL_ANY,	NO_SPECULATION),
+	VULNWL(INTEL,	5, X86_MODEL_ANY,	NO_SPECULATION),
+	VULNWL(NSC,	5, X86_MODEL_ANY,	NO_SPECULATION),
+	VULNWL(VORTEX,	5, X86_MODEL_ANY,	NO_SPECULATION),
+	VULNWL(VORTEX,	6, X86_MODEL_ANY,	NO_SPECULATION),
+
+	/* Intel Family 6 */
+	VULNWL_INTEL(TIGERLAKE,			NO_MMIO),
+	VULNWL_INTEL(TIGERLAKE_L,		NO_MMIO),
+	VULNWL_INTEL(ALDERLAKE,			NO_MMIO),
+	VULNWL_INTEL(ALDERLAKE_L,		NO_MMIO),
+
+	VULNWL_INTEL(ATOM_SALTWELL,		NO_SPECULATION | NO_ITLB_MULTIHIT),
+	VULNWL_INTEL(ATOM_SALTWELL_TABLET,	NO_SPECULATION | NO_ITLB_MULTIHIT),
+	VULNWL_INTEL(ATOM_SALTWELL_MID,		NO_SPECULATION | NO_ITLB_MULTIHIT),
+	VULNWL_INTEL(ATOM_BONNELL,		NO_SPECULATION | NO_ITLB_MULTIHIT),
+	VULNWL_INTEL(ATOM_BONNELL_MID,		NO_SPECULATION | NO_ITLB_MULTIHIT),
+
+	VULNWL_INTEL(ATOM_SILVERMONT,		NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
+	VULNWL_INTEL(ATOM_SILVERMONT_D,		NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
+	VULNWL_INTEL(ATOM_SILVERMONT_MID,	NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
+	VULNWL_INTEL(ATOM_AIRMONT,		NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
+	VULNWL_INTEL(XEON_PHI_KNL,		NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
+	VULNWL_INTEL(XEON_PHI_KNM,		NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
+
+	VULNWL_INTEL(CORE_YONAH,		NO_SSB),
+
+	VULNWL_INTEL(ATOM_AIRMONT_MID,		NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT),
+	VULNWL_INTEL(ATOM_AIRMONT_NP,		NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT),
+
+	VULNWL_INTEL(ATOM_GOLDMONT,		NO_MDS | NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO),
+	VULNWL_INTEL(ATOM_GOLDMONT_D,		NO_MDS | NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO),
+	VULNWL_INTEL(ATOM_GOLDMONT_PLUS,	NO_MDS | NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO | NO_EIBRS_PBRSB),
+
+	/*
+	 * Technically, swapgs isn't serializing on AMD (despite it previously
+	 * being documented as such in the APM).  But according to AMD, %gs is
+	 * updated non-speculatively, and the issuing of %gs-relative memory
+	 * operands will be blocked until the %gs update completes, which is
+	 * good enough for our purposes.
+	 */
+
+	VULNWL_INTEL(ATOM_TREMONT,		NO_EIBRS_PBRSB),
+	VULNWL_INTEL(ATOM_TREMONT_L,		NO_EIBRS_PBRSB),
+	VULNWL_INTEL(ATOM_TREMONT_D,		NO_ITLB_MULTIHIT | NO_EIBRS_PBRSB),
+
+	/* AMD Family 0xf - 0x12 */
+	VULNWL_AMD(0x0f,	NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO),
+	VULNWL_AMD(0x10,	NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO),
+	VULNWL_AMD(0x11,	NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO),
+	VULNWL_AMD(0x12,	NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO),
+
+	/* FAMILY_ANY must be last, otherwise 0x0f - 0x12 matches won't work */
+	VULNWL_AMD(X86_FAMILY_ANY,	NO_MELTDOWN | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO | NO_EIBRS_PBRSB),
+	VULNWL_HYGON(X86_FAMILY_ANY,	NO_MELTDOWN | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO | NO_EIBRS_PBRSB),
+
+	/* Zhaoxin Family 7 */
+	VULNWL(CENTAUR,	7, X86_MODEL_ANY,	NO_SPECTRE_V2 | NO_SWAPGS | NO_MMIO),
+	VULNWL(ZHAOXIN,	7, X86_MODEL_ANY,	NO_SPECTRE_V2 | NO_SWAPGS | NO_MMIO),
+	{}
+};
+
+#define VULNBL(vendor, family, model, blacklist)	\
+	X86_MATCH_VENDOR_FAM_MODEL(vendor, family, model, blacklist)
+
+#define VULNBL_INTEL_STEPPINGS(model, steppings, issues)		   \
+	X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE(INTEL, 6,		   \
+					    INTEL_FAM6_##model, steppings, \
+					    X86_FEATURE_ANY, issues)
+
+#define VULNBL_AMD(family, blacklist)		\
+	VULNBL(AMD, family, X86_MODEL_ANY, blacklist)
+
+#define VULNBL_HYGON(family, blacklist)		\
+	VULNBL(HYGON, family, X86_MODEL_ANY, blacklist)
+
+#define SRBDS		BIT(0)
+/* CPU is affected by X86_BUG_MMIO_STALE_DATA */
+#define MMIO		BIT(1)
+/* CPU is affected by Shared Buffers Data Sampling (SBDS), a variant of X86_BUG_MMIO_STALE_DATA */
+#define MMIO_SBDS	BIT(2)
+/* CPU is affected by RETbleed, speculating where you would not expect it */
+#define RETBLEED	BIT(3)
+/* CPU is affected by SMT (cross-thread) return predictions */
+#define SMT_RSB		BIT(4)
+/* CPU is affected by SRSO */
+#define SRSO		BIT(5)
+/* CPU is affected by GDS */
+#define GDS		BIT(6)
+
+static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = {
+	VULNBL_INTEL_STEPPINGS(IVYBRIDGE,	X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(HASWELL,		X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(HASWELL_L,	X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(HASWELL_G,	X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(HASWELL_X,	X86_STEPPING_ANY,		MMIO),
+	VULNBL_INTEL_STEPPINGS(BROADWELL_D,	X86_STEPPING_ANY,		MMIO),
+	VULNBL_INTEL_STEPPINGS(BROADWELL_G,	X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(BROADWELL_X,	X86_STEPPING_ANY,		MMIO),
+	VULNBL_INTEL_STEPPINGS(BROADWELL,	X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(SKYLAKE_X,	X86_STEPPING_ANY,		MMIO | RETBLEED | GDS),
+	VULNBL_INTEL_STEPPINGS(SKYLAKE_L,	X86_STEPPING_ANY,		MMIO | RETBLEED | GDS | SRBDS),
+	VULNBL_INTEL_STEPPINGS(SKYLAKE,		X86_STEPPING_ANY,		MMIO | RETBLEED | GDS | SRBDS),
+	VULNBL_INTEL_STEPPINGS(KABYLAKE_L,	X86_STEPPING_ANY,		MMIO | RETBLEED | GDS | SRBDS),
+	VULNBL_INTEL_STEPPINGS(KABYLAKE,	X86_STEPPING_ANY,		MMIO | RETBLEED | GDS | SRBDS),
+	VULNBL_INTEL_STEPPINGS(CANNONLAKE_L,	X86_STEPPING_ANY,		RETBLEED),
+	VULNBL_INTEL_STEPPINGS(ICELAKE_L,	X86_STEPPING_ANY,		MMIO | MMIO_SBDS | RETBLEED | GDS),
+	VULNBL_INTEL_STEPPINGS(ICELAKE_D,	X86_STEPPING_ANY,		MMIO | GDS),
+	VULNBL_INTEL_STEPPINGS(ICELAKE_X,	X86_STEPPING_ANY,		MMIO | GDS),
+	VULNBL_INTEL_STEPPINGS(COMETLAKE,	X86_STEPPING_ANY,		MMIO | MMIO_SBDS | RETBLEED | GDS),
+	VULNBL_INTEL_STEPPINGS(COMETLAKE_L,	X86_STEPPINGS(0x0, 0x0),	MMIO | RETBLEED),
+	VULNBL_INTEL_STEPPINGS(COMETLAKE_L,	X86_STEPPING_ANY,		MMIO | MMIO_SBDS | RETBLEED | GDS),
+	VULNBL_INTEL_STEPPINGS(TIGERLAKE_L,	X86_STEPPING_ANY,		GDS),
+	VULNBL_INTEL_STEPPINGS(TIGERLAKE,	X86_STEPPING_ANY,		GDS),
+	VULNBL_INTEL_STEPPINGS(LAKEFIELD,	X86_STEPPING_ANY,		MMIO | MMIO_SBDS | RETBLEED),
+	VULNBL_INTEL_STEPPINGS(ROCKETLAKE,	X86_STEPPING_ANY,		MMIO | RETBLEED | GDS),
+	VULNBL_INTEL_STEPPINGS(ATOM_TREMONT,	X86_STEPPING_ANY,		MMIO | MMIO_SBDS),
+	VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_D,	X86_STEPPING_ANY,		MMIO),
+	VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_L,	X86_STEPPING_ANY,		MMIO | MMIO_SBDS),
+
+	VULNBL_AMD(0x15, RETBLEED),
+	VULNBL_AMD(0x16, RETBLEED),
+	VULNBL_AMD(0x17, RETBLEED | SMT_RSB | SRSO),
+	VULNBL_HYGON(0x18, RETBLEED | SMT_RSB | SRSO),
+	VULNBL_AMD(0x19, SRSO),
+	{}
+};
+
+static bool __init cpu_matches(const struct x86_cpu_id *table, unsigned long which)
+{
+	const struct x86_cpu_id *m = x86_match_cpu(table);
+
+	return m && !!(m->driver_data & which);
+}
+
+u64 x86_read_arch_cap_msr(void)
+{
+	u64 ia32_cap = 0;
+
+	if (boot_cpu_has(X86_FEATURE_ARCH_CAPABILITIES))
+		rdmsrl(MSR_IA32_ARCH_CAPABILITIES, ia32_cap);
+
+	return ia32_cap;
+}
+
+static bool arch_cap_mmio_immune(u64 ia32_cap)
+{
+	return (ia32_cap & ARCH_CAP_FBSDP_NO &&
+		ia32_cap & ARCH_CAP_PSDP_NO &&
+		ia32_cap & ARCH_CAP_SBDR_SSDP_NO);
+}
+
+static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
+{
+	u64 ia32_cap = x86_read_arch_cap_msr();
+
+	/* Set ITLB_MULTIHIT bug if cpu is not in the whitelist and not mitigated */
+	if (!cpu_matches(cpu_vuln_whitelist, NO_ITLB_MULTIHIT) &&
+	    !(ia32_cap & ARCH_CAP_PSCHANGE_MC_NO))
+		setup_force_cpu_bug(X86_BUG_ITLB_MULTIHIT);
+
+	if (cpu_matches(cpu_vuln_whitelist, NO_SPECULATION))
+		return;
+
+	setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
+
+	if (!cpu_matches(cpu_vuln_whitelist, NO_SPECTRE_V2))
+		setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
+
+	if (!cpu_matches(cpu_vuln_whitelist, NO_SSB) &&
+	    !(ia32_cap & ARCH_CAP_SSB_NO) &&
+	   !cpu_has(c, X86_FEATURE_AMD_SSB_NO))
+		setup_force_cpu_bug(X86_BUG_SPEC_STORE_BYPASS);
+
+	/*
+	 * AMD's AutoIBRS is equivalent to Intel's eIBRS - use the Intel feature
+	 * flag and protect from vendor-specific bugs via the whitelist.
+	 */
+	if ((ia32_cap & ARCH_CAP_IBRS_ALL) || cpu_has(c, X86_FEATURE_AUTOIBRS)) {
+		setup_force_cpu_cap(X86_FEATURE_IBRS_ENHANCED);
+		if (!cpu_matches(cpu_vuln_whitelist, NO_EIBRS_PBRSB) &&
+		    !(ia32_cap & ARCH_CAP_PBRSB_NO))
+			setup_force_cpu_bug(X86_BUG_EIBRS_PBRSB);
+	}
+
+	if (!cpu_matches(cpu_vuln_whitelist, NO_MDS) &&
+	    !(ia32_cap & ARCH_CAP_MDS_NO)) {
+		setup_force_cpu_bug(X86_BUG_MDS);
+		if (cpu_matches(cpu_vuln_whitelist, MSBDS_ONLY))
+			setup_force_cpu_bug(X86_BUG_MSBDS_ONLY);
+	}
+
+	if (!cpu_matches(cpu_vuln_whitelist, NO_SWAPGS))
+		setup_force_cpu_bug(X86_BUG_SWAPGS);
+
+	/*
+	 * When the CPU is not mitigated for TAA (TAA_NO=0) set TAA bug when:
+	 *	- TSX is supported or
+	 *	- TSX_CTRL is present
+	 *
+	 * TSX_CTRL check is needed for cases when TSX could be disabled before
+	 * the kernel boot e.g. kexec.
+	 * TSX_CTRL check alone is not sufficient for cases when the microcode
+	 * update is not present or running as guest that don't get TSX_CTRL.
+	 */
+	if (!(ia32_cap & ARCH_CAP_TAA_NO) &&
+	    (cpu_has(c, X86_FEATURE_RTM) ||
+	     (ia32_cap & ARCH_CAP_TSX_CTRL_MSR)))
+		setup_force_cpu_bug(X86_BUG_TAA);
+
+	/*
+	 * SRBDS affects CPUs which support RDRAND or RDSEED and are listed
+	 * in the vulnerability blacklist.
+	 *
+	 * Some of the implications and mitigation of Shared Buffers Data
+	 * Sampling (SBDS) are similar to SRBDS. Give SBDS same treatment as
+	 * SRBDS.
+	 */
+	if ((cpu_has(c, X86_FEATURE_RDRAND) ||
+	     cpu_has(c, X86_FEATURE_RDSEED)) &&
+	    cpu_matches(cpu_vuln_blacklist, SRBDS | MMIO_SBDS))
+		    setup_force_cpu_bug(X86_BUG_SRBDS);
+
+	/*
+	 * Processor MMIO Stale Data bug enumeration
+	 *
+	 * Affected CPU list is generally enough to enumerate the vulnerability,
+	 * but for virtualization case check for ARCH_CAP MSR bits also, VMM may
+	 * not want the guest to enumerate the bug.
+	 *
+	 * Set X86_BUG_MMIO_UNKNOWN for CPUs that are neither in the blacklist,
+	 * nor in the whitelist and also don't enumerate MSR ARCH_CAP MMIO bits.
+	 */
+	if (!arch_cap_mmio_immune(ia32_cap)) {
+		if (cpu_matches(cpu_vuln_blacklist, MMIO))
+			setup_force_cpu_bug(X86_BUG_MMIO_STALE_DATA);
+		else if (!cpu_matches(cpu_vuln_whitelist, NO_MMIO))
+			setup_force_cpu_bug(X86_BUG_MMIO_UNKNOWN);
+	}
+
+	if (!cpu_has(c, X86_FEATURE_BTC_NO)) {
+		if (cpu_matches(cpu_vuln_blacklist, RETBLEED) || (ia32_cap & ARCH_CAP_RSBA))
+			setup_force_cpu_bug(X86_BUG_RETBLEED);
+	}
+
+	if (cpu_matches(cpu_vuln_blacklist, SMT_RSB))
+		setup_force_cpu_bug(X86_BUG_SMT_RSB);
+
+	if (!cpu_has(c, X86_FEATURE_SRSO_NO)) {
+		if (cpu_matches(cpu_vuln_blacklist, SRSO))
+			setup_force_cpu_bug(X86_BUG_SRSO);
+	}
+
+	/*
+	 * Check if CPU is vulnerable to GDS. If running in a virtual machine on
+	 * an affected processor, the VMM may have disabled the use of GATHER by
+	 * disabling AVX2. The only way to do this in HW is to clear XCR0[2],
+	 * which means that AVX will be disabled.
+	 */
+	if (cpu_matches(cpu_vuln_blacklist, GDS) && !(ia32_cap & ARCH_CAP_GDS_NO) &&
+	    boot_cpu_has(X86_FEATURE_AVX))
+		setup_force_cpu_bug(X86_BUG_GDS);
+
+	if (cpu_matches(cpu_vuln_whitelist, NO_MELTDOWN))
+		return;
+
+	/* Rogue Data Cache Load? No! */
+	if (ia32_cap & ARCH_CAP_RDCL_NO)
+		return;
+
+	setup_force_cpu_bug(X86_BUG_CPU_MELTDOWN);
+
+	if (cpu_matches(cpu_vuln_whitelist, NO_L1TF))
+		return;
+
+	setup_force_cpu_bug(X86_BUG_L1TF);
+}
+
+/*
+ * The NOPL instruction is supposed to exist on all CPUs of family >= 6;
+ * unfortunately, that's not true in practice because of early VIA
+ * chips and (more importantly) broken virtualizers that are not easy
+ * to detect. In the latter case it doesn't even *fail* reliably, so
+ * probing for it doesn't even work. Disable it completely on 32-bit
+ * unless we can find a reliable way to detect all the broken cases.
+ * Enable it explicitly on 64-bit for non-constant inputs of cpu_has().
+ */
+static void detect_nopl(void)
+{
+#ifdef CONFIG_X86_32
+	setup_clear_cpu_cap(X86_FEATURE_NOPL);
+#else
+	setup_force_cpu_cap(X86_FEATURE_NOPL);
+#endif
+}
+
+/*
+ * We parse cpu parameters early because fpu__init_system() is executed
+ * before parse_early_param().
+ */
+static void __init cpu_parse_early_param(void)
+{
+	char arg[128];
+	char *argptr = arg, *opt;
+	int arglen, taint = 0;
+
+#ifdef CONFIG_X86_32
+	if (cmdline_find_option_bool(boot_command_line, "no387"))
+#ifdef CONFIG_MATH_EMULATION
+		setup_clear_cpu_cap(X86_FEATURE_FPU);
+#else
+		pr_err("Option 'no387' required CONFIG_MATH_EMULATION enabled.\n");
+#endif
+
+	if (cmdline_find_option_bool(boot_command_line, "nofxsr"))
+		setup_clear_cpu_cap(X86_FEATURE_FXSR);
+#endif
+
+	if (cmdline_find_option_bool(boot_command_line, "noxsave"))
+		setup_clear_cpu_cap(X86_FEATURE_XSAVE);
+
+	if (cmdline_find_option_bool(boot_command_line, "noxsaveopt"))
+		setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT);
+
+	if (cmdline_find_option_bool(boot_command_line, "noxsaves"))
+		setup_clear_cpu_cap(X86_FEATURE_XSAVES);
+
+	if (cmdline_find_option_bool(boot_command_line, "nousershstk"))
+		setup_clear_cpu_cap(X86_FEATURE_USER_SHSTK);
+
+	arglen = cmdline_find_option(boot_command_line, "clearcpuid", arg, sizeof(arg));
+	if (arglen <= 0)
+		return;
+
+	pr_info("Clearing CPUID bits:");
+
+	while (argptr) {
+		bool found __maybe_unused = false;
+		unsigned int bit;
+
+		opt = strsep(&argptr, ",");
+
+		/*
+		 * Handle naked numbers first for feature flags which don't
+		 * have names.
+		 */
+		if (!kstrtouint(opt, 10, &bit)) {
+			if (bit < NCAPINTS * 32) {
+
+				/* empty-string, i.e., ""-defined feature flags */
+				if (!x86_cap_flags[bit])
+					pr_cont(" " X86_CAP_FMT_NUM, x86_cap_flag_num(bit));
+				else
+					pr_cont(" " X86_CAP_FMT, x86_cap_flag(bit));
+
+				setup_clear_cpu_cap(bit);
+				taint++;
+			}
+			/*
+			 * The assumption is that there are no feature names with only
+			 * numbers in the name thus go to the next argument.
+			 */
+			continue;
+		}
+
+		for (bit = 0; bit < 32 * NCAPINTS; bit++) {
+			if (!x86_cap_flag(bit))
+				continue;
+
+			if (strcmp(x86_cap_flag(bit), opt))
+				continue;
+
+			pr_cont(" %s", opt);
+			setup_clear_cpu_cap(bit);
+			taint++;
+			found = true;
+			break;
+		}
+
+		if (!found)
+			pr_cont(" (unknown: %s)", opt);
+	}
+	pr_cont("\n");
+
+	if (taint)
+		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
+}
+
+/*
+ * Do minimum CPU detection early.
+ * Fields really needed: vendor, cpuid_level, family, model, mask,
+ * cache alignment.
+ * The others are not touched to avoid unwanted side effects.
+ *
+ * WARNING: this function is only called on the boot CPU.  Don't add code
+ * here that is supposed to run on all CPUs.
+ */
+static void __init early_identify_cpu(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_X86_64
+	c->x86_clflush_size = 64;
+	c->x86_phys_bits = 36;
+	c->x86_virt_bits = 48;
+#else
+	c->x86_clflush_size = 32;
+	c->x86_phys_bits = 32;
+	c->x86_virt_bits = 32;
+#endif
+	c->x86_cache_alignment = c->x86_clflush_size;
+
+	memset(&c->x86_capability, 0, sizeof(c->x86_capability));
+	c->extended_cpuid_level = 0;
+
+	if (!have_cpuid_p())
+		identify_cpu_without_cpuid(c);
+
+	/* cyrix could have cpuid enabled via c_identify()*/
+	if (have_cpuid_p()) {
+		cpu_detect(c);
+		get_cpu_vendor(c);
+		get_cpu_cap(c);
+		get_cpu_address_sizes(c);
+		setup_force_cpu_cap(X86_FEATURE_CPUID);
+		cpu_parse_early_param();
+
+		if (this_cpu->c_early_init)
+			this_cpu->c_early_init(c);
+
+		c->cpu_index = 0;
+		filter_cpuid_features(c, false);
+
+		if (this_cpu->c_bsp_init)
+			this_cpu->c_bsp_init(c);
+	} else {
+		setup_clear_cpu_cap(X86_FEATURE_CPUID);
+	}
+
+	setup_force_cpu_cap(X86_FEATURE_ALWAYS);
+
+	cpu_set_bug_bits(c);
+
+	sld_setup(c);
+
+#ifdef CONFIG_X86_32
+	/*
+	 * Regardless of whether PCID is enumerated, the SDM says
+	 * that it can't be enabled in 32-bit mode.
+	 */
+	setup_clear_cpu_cap(X86_FEATURE_PCID);
+#endif
+
+	/*
+	 * Later in the boot process pgtable_l5_enabled() relies on
+	 * cpu_feature_enabled(X86_FEATURE_LA57). If 5-level paging is not
+	 * enabled by this point we need to clear the feature bit to avoid
+	 * false-positives at the later stage.
+	 *
+	 * pgtable_l5_enabled() can be false here for several reasons:
+	 *  - 5-level paging is disabled compile-time;
+	 *  - it's 32-bit kernel;
+	 *  - machine doesn't support 5-level paging;
+	 *  - user specified 'no5lvl' in kernel command line.
+	 */
+	if (!pgtable_l5_enabled())
+		setup_clear_cpu_cap(X86_FEATURE_LA57);
+
+	detect_nopl();
+}
+
+void __init early_cpu_init(void)
+{
+	const struct cpu_dev *const *cdev;
+	int count = 0;
+
+#ifdef CONFIG_PROCESSOR_SELECT
+	pr_info("KERNEL supported cpus:\n");
+#endif
+
+	for (cdev = __x86_cpu_dev_start; cdev < __x86_cpu_dev_end; cdev++) {
+		const struct cpu_dev *cpudev = *cdev;
+
+		if (count >= X86_VENDOR_NUM)
+			break;
+		cpu_devs[count] = cpudev;
+		count++;
+
+#ifdef CONFIG_PROCESSOR_SELECT
+		{
+			unsigned int j;
+
+			for (j = 0; j < 2; j++) {
+				if (!cpudev->c_ident[j])
+					continue;
+				pr_info("  %s %s\n", cpudev->c_vendor,
+					cpudev->c_ident[j]);
+			}
+		}
+#endif
+	}
+	early_identify_cpu(&boot_cpu_data);
+}
+
+static bool detect_null_seg_behavior(void)
+{
+	/*
+	 * Empirically, writing zero to a segment selector on AMD does
+	 * not clear the base, whereas writing zero to a segment
+	 * selector on Intel does clear the base.  Intel's behavior
+	 * allows slightly faster context switches in the common case
+	 * where GS is unused by the prev and next threads.
+	 *
+	 * Since neither vendor documents this anywhere that I can see,
+	 * detect it directly instead of hard-coding the choice by
+	 * vendor.
+	 *
+	 * I've designated AMD's behavior as the "bug" because it's
+	 * counterintuitive and less friendly.
+	 */
+
+	unsigned long old_base, tmp;
+	rdmsrl(MSR_FS_BASE, old_base);
+	wrmsrl(MSR_FS_BASE, 1);
+	loadsegment(fs, 0);
+	rdmsrl(MSR_FS_BASE, tmp);
+	wrmsrl(MSR_FS_BASE, old_base);
+	return tmp == 0;
+}
+
+void check_null_seg_clears_base(struct cpuinfo_x86 *c)
+{
+	/* BUG_NULL_SEG is only relevant with 64bit userspace */
+	if (!IS_ENABLED(CONFIG_X86_64))
+		return;
+
+	if (cpu_has(c, X86_FEATURE_NULL_SEL_CLR_BASE))
+		return;
+
+	/*
+	 * CPUID bit above wasn't set. If this kernel is still running
+	 * as a HV guest, then the HV has decided not to advertize
+	 * that CPUID bit for whatever reason.	For example, one
+	 * member of the migration pool might be vulnerable.  Which
+	 * means, the bug is present: set the BUG flag and return.
+	 */
+	if (cpu_has(c, X86_FEATURE_HYPERVISOR)) {
+		set_cpu_bug(c, X86_BUG_NULL_SEG);
+		return;
+	}
+
+	/*
+	 * Zen2 CPUs also have this behaviour, but no CPUID bit.
+	 * 0x18 is the respective family for Hygon.
+	 */
+	if ((c->x86 == 0x17 || c->x86 == 0x18) &&
+	    detect_null_seg_behavior())
+		return;
+
+	/* All the remaining ones are affected */
+	set_cpu_bug(c, X86_BUG_NULL_SEG);
+}
+
+static void generic_identify(struct cpuinfo_x86 *c)
+{
+	c->extended_cpuid_level = 0;
+
+	if (!have_cpuid_p())
+		identify_cpu_without_cpuid(c);
+
+	/* cyrix could have cpuid enabled via c_identify()*/
+	if (!have_cpuid_p())
+		return;
+
+	cpu_detect(c);
+
+	get_cpu_vendor(c);
+
+	get_cpu_cap(c);
+
+	get_cpu_address_sizes(c);
+
+	if (c->cpuid_level >= 0x00000001) {
+		c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF;
+#ifdef CONFIG_X86_32
+# ifdef CONFIG_SMP
+		c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
+# else
+		c->apicid = c->initial_apicid;
+# endif
+#endif
+		c->phys_proc_id = c->initial_apicid;
+	}
+
+	get_model_name(c); /* Default name */
+
+	/*
+	 * ESPFIX is a strange bug.  All real CPUs have it.  Paravirt
+	 * systems that run Linux at CPL > 0 may or may not have the
+	 * issue, but, even if they have the issue, there's absolutely
+	 * nothing we can do about it because we can't use the real IRET
+	 * instruction.
+	 *
+	 * NB: For the time being, only 32-bit kernels support
+	 * X86_BUG_ESPFIX as such.  64-bit kernels directly choose
+	 * whether to apply espfix using paravirt hooks.  If any
+	 * non-paravirt system ever shows up that does *not* have the
+	 * ESPFIX issue, we can change this.
+	 */
+#ifdef CONFIG_X86_32
+	set_cpu_bug(c, X86_BUG_ESPFIX);
+#endif
+}
+
+/*
+ * Validate that ACPI/mptables have the same information about the
+ * effective APIC id and update the package map.
+ */
+static void validate_apic_and_package_id(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_SMP
+	unsigned int apicid, cpu = smp_processor_id();
+
+	apicid = apic->cpu_present_to_apicid(cpu);
+
+	if (apicid != c->apicid) {
+		pr_err(FW_BUG "CPU%u: APIC id mismatch. Firmware: %x APIC: %x\n",
+		       cpu, apicid, c->initial_apicid);
+	}
+	BUG_ON(topology_update_package_map(c->phys_proc_id, cpu));
+	BUG_ON(topology_update_die_map(c->cpu_die_id, cpu));
+#else
+	c->logical_proc_id = 0;
+#endif
+}
+
+/*
+ * This does the hard work of actually picking apart the CPU stuff...
+ */
+static void identify_cpu(struct cpuinfo_x86 *c)
+{
+	int i;
+
+	c->loops_per_jiffy = loops_per_jiffy;
+	c->x86_cache_size = 0;
+	c->x86_vendor = X86_VENDOR_UNKNOWN;
+	c->x86_model = c->x86_stepping = 0;	/* So far unknown... */
+	c->x86_vendor_id[0] = '\0'; /* Unset */
+	c->x86_model_id[0] = '\0';  /* Unset */
+	c->x86_max_cores = 1;
+	c->x86_coreid_bits = 0;
+	c->cu_id = 0xff;
+#ifdef CONFIG_X86_64
+	c->x86_clflush_size = 64;
+	c->x86_phys_bits = 36;
+	c->x86_virt_bits = 48;
+#else
+	c->cpuid_level = -1;	/* CPUID not detected */
+	c->x86_clflush_size = 32;
+	c->x86_phys_bits = 32;
+	c->x86_virt_bits = 32;
+#endif
+	c->x86_cache_alignment = c->x86_clflush_size;
+	memset(&c->x86_capability, 0, sizeof(c->x86_capability));
+#ifdef CONFIG_X86_VMX_FEATURE_NAMES
+	memset(&c->vmx_capability, 0, sizeof(c->vmx_capability));
+#endif
+
+	generic_identify(c);
+
+	if (this_cpu->c_identify)
+		this_cpu->c_identify(c);
+
+	/* Clear/Set all flags overridden by options, after probe */
+	apply_forced_caps(c);
+
+#ifdef CONFIG_X86_64
+	c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
+#endif
+
+	/*
+	 * Vendor-specific initialization.  In this section we
+	 * canonicalize the feature flags, meaning if there are
+	 * features a certain CPU supports which CPUID doesn't
+	 * tell us, CPUID claiming incorrect flags, or other bugs,
+	 * we handle them here.
+	 *
+	 * At the end of this section, c->x86_capability better
+	 * indicate the features this CPU genuinely supports!
+	 */
+	if (this_cpu->c_init)
+		this_cpu->c_init(c);
+
+	/* Disable the PN if appropriate */
+	squash_the_stupid_serial_number(c);
+
+	/* Set up SMEP/SMAP/UMIP */
+	setup_smep(c);
+	setup_smap(c);
+	setup_umip(c);
+
+	/* Enable FSGSBASE instructions if available. */
+	if (cpu_has(c, X86_FEATURE_FSGSBASE)) {
+		cr4_set_bits(X86_CR4_FSGSBASE);
+		elf_hwcap2 |= HWCAP2_FSGSBASE;
+	}
+
+	/*
+	 * The vendor-specific functions might have changed features.
+	 * Now we do "generic changes."
+	 */
+
+	/* Filter out anything that depends on CPUID levels we don't have */
+	filter_cpuid_features(c, true);
+
+	/* If the model name is still unset, do table lookup. */
+	if (!c->x86_model_id[0]) {
+		const char *p;
+		p = table_lookup_model(c);
+		if (p)
+			strcpy(c->x86_model_id, p);
+		else
+			/* Last resort... */
+			sprintf(c->x86_model_id, "%02x/%02x",
+				c->x86, c->x86_model);
+	}
+
+#ifdef CONFIG_X86_64
+	detect_ht(c);
+#endif
+
+	x86_init_rdrand(c);
+	setup_pku(c);
+	setup_cet(c);
+
+	/*
+	 * Clear/Set all flags overridden by options, need do it
+	 * before following smp all cpus cap AND.
+	 */
+	apply_forced_caps(c);
+
+	/*
+	 * On SMP, boot_cpu_data holds the common feature set between
+	 * all CPUs; so make sure that we indicate which features are
+	 * common between the CPUs.  The first time this routine gets
+	 * executed, c == &boot_cpu_data.
+	 */
+	if (c != &boot_cpu_data) {
+		/* AND the already accumulated flags with these */
+		for (i = 0; i < NCAPINTS; i++)
+			boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
+
+		/* OR, i.e. replicate the bug flags */
+		for (i = NCAPINTS; i < NCAPINTS + NBUGINTS; i++)
+			c->x86_capability[i] |= boot_cpu_data.x86_capability[i];
+	}
+
+	ppin_init(c);
+
+	/* Init Machine Check Exception if available. */
+	mcheck_cpu_init(c);
+
+	select_idle_routine(c);
+
+#ifdef CONFIG_NUMA
+	numa_add_cpu(smp_processor_id());
+#endif
+}
+
+/*
+ * Set up the CPU state needed to execute SYSENTER/SYSEXIT instructions
+ * on 32-bit kernels:
+ */
+#ifdef CONFIG_X86_32
+void enable_sep_cpu(void)
+{
+	struct tss_struct *tss;
+	int cpu;
+
+	if (!boot_cpu_has(X86_FEATURE_SEP))
+		return;
+
+	cpu = get_cpu();
+	tss = &per_cpu(cpu_tss_rw, cpu);
+
+	/*
+	 * We cache MSR_IA32_SYSENTER_CS's value in the TSS's ss1 field --
+	 * see the big comment in struct x86_hw_tss's definition.
+	 */
+
+	tss->x86_tss.ss1 = __KERNEL_CS;
+	wrmsr(MSR_IA32_SYSENTER_CS, tss->x86_tss.ss1, 0);
+	wrmsr(MSR_IA32_SYSENTER_ESP, (unsigned long)(cpu_entry_stack(cpu) + 1), 0);
+	wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long)entry_SYSENTER_32, 0);
+
+	put_cpu();
+}
+#endif
+
+static __init void identify_boot_cpu(void)
+{
+	identify_cpu(&boot_cpu_data);
+	if (HAS_KERNEL_IBT && cpu_feature_enabled(X86_FEATURE_IBT))
+		pr_info("CET detected: Indirect Branch Tracking enabled\n");
+#ifdef CONFIG_X86_32
+	enable_sep_cpu();
+#endif
+	cpu_detect_tlb(&boot_cpu_data);
+	setup_cr_pinning();
+
+	tsx_init();
+	lkgs_init();
+}
+
+void identify_secondary_cpu(struct cpuinfo_x86 *c)
+{
+	BUG_ON(c == &boot_cpu_data);
+	identify_cpu(c);
+#ifdef CONFIG_X86_32
+	enable_sep_cpu();
+#endif
+	validate_apic_and_package_id(c);
+	x86_spec_ctrl_setup_ap();
+	update_srbds_msr();
+	if (boot_cpu_has_bug(X86_BUG_GDS))
+		update_gds_msr();
+
+	tsx_ap_init();
+}
+
+void print_cpu_info(struct cpuinfo_x86 *c)
+{
+	const char *vendor = NULL;
+
+	if (c->x86_vendor < X86_VENDOR_NUM) {
+		vendor = this_cpu->c_vendor;
+	} else {
+		if (c->cpuid_level >= 0)
+			vendor = c->x86_vendor_id;
+	}
+
+	if (vendor && !strstr(c->x86_model_id, vendor))
+		pr_cont("%s ", vendor);
+
+	if (c->x86_model_id[0])
+		pr_cont("%s", c->x86_model_id);
+	else
+		pr_cont("%d86", c->x86);
+
+	pr_cont(" (family: 0x%x, model: 0x%x", c->x86, c->x86_model);
+
+	if (c->x86_stepping || c->cpuid_level >= 0)
+		pr_cont(", stepping: 0x%x)\n", c->x86_stepping);
+	else
+		pr_cont(")\n");
+}
+
+/*
+ * clearcpuid= was already parsed in cpu_parse_early_param().  This dummy
+ * function prevents it from becoming an environment variable for init.
+ */
+static __init int setup_clearcpuid(char *arg)
+{
+	return 1;
+}
+__setup("clearcpuid=", setup_clearcpuid);
+
+DEFINE_PER_CPU_ALIGNED(struct pcpu_hot, pcpu_hot) = {
+	.current_task	= &init_task,
+	.preempt_count	= INIT_PREEMPT_COUNT,
+	.top_of_stack	= TOP_OF_INIT_STACK,
+};
+EXPORT_PER_CPU_SYMBOL(pcpu_hot);
+
+#ifdef CONFIG_X86_64
+DEFINE_PER_CPU_FIRST(struct fixed_percpu_data,
+		     fixed_percpu_data) __aligned(PAGE_SIZE) __visible;
+EXPORT_PER_CPU_SYMBOL_GPL(fixed_percpu_data);
+
+static void wrmsrl_cstar(unsigned long val)
+{
+	/*
+	 * Intel CPUs do not support 32-bit SYSCALL. Writing to MSR_CSTAR
+	 * is so far ignored by the CPU, but raises a #VE trap in a TDX
+	 * guest. Avoid the pointless write on all Intel CPUs.
+	 */
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
+		wrmsrl(MSR_CSTAR, val);
+}
+
+/* May not be marked __init: used by software suspend */
+void syscall_init(void)
+{
+	wrmsr(MSR_STAR, 0, (__USER32_CS << 16) | __KERNEL_CS);
+	wrmsrl(MSR_LSTAR, (unsigned long)entry_SYSCALL_64);
+
+#ifdef CONFIG_IA32_EMULATION
+	wrmsrl_cstar((unsigned long)entry_SYSCALL_compat);
+	/*
+	 * This only works on Intel CPUs.
+	 * On AMD CPUs these MSRs are 32-bit, CPU truncates MSR_IA32_SYSENTER_EIP.
+	 * This does not cause SYSENTER to jump to the wrong location, because
+	 * AMD doesn't allow SYSENTER in long mode (either 32- or 64-bit).
+	 */
+	wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS);
+	wrmsrl_safe(MSR_IA32_SYSENTER_ESP,
+		    (unsigned long)(cpu_entry_stack(smp_processor_id()) + 1));
+	wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)entry_SYSENTER_compat);
+#else
+	wrmsrl_cstar((unsigned long)ignore_sysret);
+	wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)GDT_ENTRY_INVALID_SEG);
+	wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL);
+	wrmsrl_safe(MSR_IA32_SYSENTER_EIP, 0ULL);
+#endif
+
+	/*
+	 * Flags to clear on syscall; clear as much as possible
+	 * to minimize user space-kernel interference.
+	 */
+	wrmsrl(MSR_SYSCALL_MASK,
+	       X86_EFLAGS_CF|X86_EFLAGS_PF|X86_EFLAGS_AF|
+	       X86_EFLAGS_ZF|X86_EFLAGS_SF|X86_EFLAGS_TF|
+	       X86_EFLAGS_IF|X86_EFLAGS_DF|X86_EFLAGS_OF|
+	       X86_EFLAGS_IOPL|X86_EFLAGS_NT|X86_EFLAGS_RF|
+	       X86_EFLAGS_AC|X86_EFLAGS_ID);
+}
+
+#else	/* CONFIG_X86_64 */
+
+#ifdef CONFIG_STACKPROTECTOR
+DEFINE_PER_CPU(unsigned long, __stack_chk_guard);
+EXPORT_PER_CPU_SYMBOL(__stack_chk_guard);
+#endif
+
+#endif	/* CONFIG_X86_64 */
+
+/*
+ * Clear all 6 debug registers:
+ */
+static void clear_all_debug_regs(void)
+{
+	int i;
+
+	for (i = 0; i < 8; i++) {
+		/* Ignore db4, db5 */
+		if ((i == 4) || (i == 5))
+			continue;
+
+		set_debugreg(0, i);
+	}
+}
+
+#ifdef CONFIG_KGDB
+/*
+ * Restore debug regs if using kgdbwait and you have a kernel debugger
+ * connection established.
+ */
+static void dbg_restore_debug_regs(void)
+{
+	if (unlikely(kgdb_connected && arch_kgdb_ops.correct_hw_break))
+		arch_kgdb_ops.correct_hw_break();
+}
+#else /* ! CONFIG_KGDB */
+#define dbg_restore_debug_regs()
+#endif /* ! CONFIG_KGDB */
+
+static inline void setup_getcpu(int cpu)
+{
+	unsigned long cpudata = vdso_encode_cpunode(cpu, early_cpu_to_node(cpu));
+	struct desc_struct d = { };
+
+	if (boot_cpu_has(X86_FEATURE_RDTSCP) || boot_cpu_has(X86_FEATURE_RDPID))
+		wrmsr(MSR_TSC_AUX, cpudata, 0);
+
+	/* Store CPU and node number in limit. */
+	d.limit0 = cpudata;
+	d.limit1 = cpudata >> 16;
+
+	d.type = 5;		/* RO data, expand down, accessed */
+	d.dpl = 3;		/* Visible to user code */
+	d.s = 1;		/* Not a system segment */
+	d.p = 1;		/* Present */
+	d.d = 1;		/* 32-bit */
+
+	write_gdt_entry(get_cpu_gdt_rw(cpu), GDT_ENTRY_CPUNODE, &d, DESCTYPE_S);
+}
+
+#ifdef CONFIG_X86_64
+static inline void ucode_cpu_init(int cpu) { }
+
+static inline void tss_setup_ist(struct tss_struct *tss)
+{
+	/* Set up the per-CPU TSS IST stacks */
+	tss->x86_tss.ist[IST_INDEX_DF] = __this_cpu_ist_top_va(DF);
+	tss->x86_tss.ist[IST_INDEX_NMI] = __this_cpu_ist_top_va(NMI);
+	tss->x86_tss.ist[IST_INDEX_DB] = __this_cpu_ist_top_va(DB);
+	tss->x86_tss.ist[IST_INDEX_MCE] = __this_cpu_ist_top_va(MCE);
+	/* Only mapped when SEV-ES is active */
+	tss->x86_tss.ist[IST_INDEX_VC] = __this_cpu_ist_top_va(VC);
+}
+
+#else /* CONFIG_X86_64 */
+
+static inline void ucode_cpu_init(int cpu)
+{
+	show_ucode_info_early();
+}
+
+static inline void tss_setup_ist(struct tss_struct *tss) { }
+
+#endif /* !CONFIG_X86_64 */
+
+static inline void tss_setup_io_bitmap(struct tss_struct *tss)
+{
+	tss->x86_tss.io_bitmap_base = IO_BITMAP_OFFSET_INVALID;
+
+#ifdef CONFIG_X86_IOPL_IOPERM
+	tss->io_bitmap.prev_max = 0;
+	tss->io_bitmap.prev_sequence = 0;
+	memset(tss->io_bitmap.bitmap, 0xff, sizeof(tss->io_bitmap.bitmap));
+	/*
+	 * Invalidate the extra array entry past the end of the all
+	 * permission bitmap as required by the hardware.
+	 */
+	tss->io_bitmap.mapall[IO_BITMAP_LONGS] = ~0UL;
+#endif
+}
+
+/*
+ * Setup everything needed to handle exceptions from the IDT, including the IST
+ * exceptions which use paranoid_entry().
+ */
+void cpu_init_exception_handling(void)
+{
+	struct tss_struct *tss = this_cpu_ptr(&cpu_tss_rw);
+	int cpu = raw_smp_processor_id();
+
+	/* paranoid_entry() gets the CPU number from the GDT */
+	setup_getcpu(cpu);
+
+	/* IST vectors need TSS to be set up. */
+	tss_setup_ist(tss);
+	tss_setup_io_bitmap(tss);
+	set_tss_desc(cpu, &get_cpu_entry_area(cpu)->tss.x86_tss);
+
+	load_TR_desc();
+
+	/* GHCB needs to be setup to handle #VC. */
+	setup_ghcb();
+
+	/* Finally load the IDT */
+	load_current_idt();
+}
+
+/*
+ * cpu_init() initializes state that is per-CPU. Some data is already
+ * initialized (naturally) in the bootstrap process, such as the GDT.  We
+ * reload it nevertheless, this function acts as a 'CPU state barrier',
+ * nothing should get across.
+ */
+void cpu_init(void)
+{
+	struct task_struct *cur = current;
+	int cpu = raw_smp_processor_id();
+
+	ucode_cpu_init(cpu);
+
+#ifdef CONFIG_NUMA
+	if (this_cpu_read(numa_node) == 0 &&
+	    early_cpu_to_node(cpu) != NUMA_NO_NODE)
+		set_numa_node(early_cpu_to_node(cpu));
+#endif
+	pr_debug("Initializing CPU#%d\n", cpu);
+
+	if (IS_ENABLED(CONFIG_X86_64) || cpu_feature_enabled(X86_FEATURE_VME) ||
+	    boot_cpu_has(X86_FEATURE_TSC) || boot_cpu_has(X86_FEATURE_DE))
+		cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
+
+	if (IS_ENABLED(CONFIG_X86_64)) {
+		loadsegment(fs, 0);
+		memset(cur->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);
+		syscall_init();
+
+		wrmsrl(MSR_FS_BASE, 0);
+		wrmsrl(MSR_KERNEL_GS_BASE, 0);
+		barrier();
+
+		x2apic_setup();
+	}
+
+	mmgrab(&init_mm);
+	cur->active_mm = &init_mm;
+	BUG_ON(cur->mm);
+	initialize_tlbstate_and_flush();
+	enter_lazy_tlb(&init_mm, cur);
+
+	/*
+	 * sp0 points to the entry trampoline stack regardless of what task
+	 * is running.
+	 */
+	load_sp0((unsigned long)(cpu_entry_stack(cpu) + 1));
+
+	load_mm_ldt(&init_mm);
+
+	clear_all_debug_regs();
+	dbg_restore_debug_regs();
+
+	doublefault_init_cpu_tss();
+
+	if (is_uv_system())
+		uv_cpu_init();
+
+	load_fixmap_gdt(cpu);
+}
+
+#ifdef CONFIG_MICROCODE_LATE_LOADING
+/**
+ * store_cpu_caps() - Store a snapshot of CPU capabilities
+ * @curr_info: Pointer where to store it
+ *
+ * Returns: None
+ */
+void store_cpu_caps(struct cpuinfo_x86 *curr_info)
+{
+	/* Reload CPUID max function as it might've changed. */
+	curr_info->cpuid_level = cpuid_eax(0);
+
+	/* Copy all capability leafs and pick up the synthetic ones. */
+	memcpy(&curr_info->x86_capability, &boot_cpu_data.x86_capability,
+	       sizeof(curr_info->x86_capability));
+
+	/* Get the hardware CPUID leafs */
+	get_cpu_cap(curr_info);
+}
+
+/**
+ * microcode_check() - Check if any CPU capabilities changed after an update.
+ * @prev_info:	CPU capabilities stored before an update.
+ *
+ * The microcode loader calls this upon late microcode load to recheck features,
+ * only when microcode has been updated. Caller holds and CPU hotplug lock.
+ *
+ * Return: None
+ */
+void microcode_check(struct cpuinfo_x86 *prev_info)
+{
+	struct cpuinfo_x86 curr_info;
+
+	perf_check_microcode();
+
+	amd_check_microcode();
+
+	store_cpu_caps(&curr_info);
+
+	if (!memcmp(&prev_info->x86_capability, &curr_info.x86_capability,
+		    sizeof(prev_info->x86_capability)))
+		return;
+
+	pr_warn("x86/CPU: CPU features have changed after loading microcode, but might not take effect.\n");
+	pr_warn("x86/CPU: Please consider either early loading through initrd/built-in or a potential BIOS update.\n");
+}
+#endif
+
+/*
+ * Invoked from core CPU hotplug code after hotplug operations
+ */
+void arch_smt_update(void)
+{
+	/* Handle the speculative execution misfeatures */
+	cpu_bugs_smt_update();
+	/* Check whether IPI broadcasting can be enabled */
+	apic_smt_update();
+}
+
+void __init arch_cpu_finalize_init(void)
+{
+	identify_boot_cpu();
+
+	/*
+	 * identify_boot_cpu() initialized SMT support information, let the
+	 * core code know.
+	 */
+	cpu_smt_set_num_threads(smp_num_siblings, smp_num_siblings);
+
+	if (!IS_ENABLED(CONFIG_SMP)) {
+		pr_info("CPU: ");
+		print_cpu_info(&boot_cpu_data);
+	}
+
+	cpu_select_mitigations();
+
+	arch_smt_update();
+
+	if (IS_ENABLED(CONFIG_X86_32)) {
+		/*
+		 * Check whether this is a real i386 which is not longer
+		 * supported and fixup the utsname.
+		 */
+		if (boot_cpu_data.x86 < 4)
+			panic("Kernel requires i486+ for 'invlpg' and other features");
+
+		init_utsname()->machine[1] =
+			'0' + (boot_cpu_data.x86 > 6 ? 6 : boot_cpu_data.x86);
+	}
+
+	/*
+	 * Must be before alternatives because it might set or clear
+	 * feature bits.
+	 */
+	fpu__init_system();
+	fpu__init_cpu();
+
+	alternative_instructions();
+
+	if (IS_ENABLED(CONFIG_X86_64)) {
+		/*
+		 * Make sure the first 2MB area is not mapped by huge pages
+		 * There are typically fixed size MTRRs in there and overlapping
+		 * MTRRs into large pages causes slow downs.
+		 *
+		 * Right now we don't do that with gbpages because there seems
+		 * very little benefit for that case.
+		 */
+		if (!direct_gbpages)
+			set_memory_4k((unsigned long)__va(0), 1);
+	} else {
+		fpu__init_check_bugs();
+	}
+
+	/*
+	 * This needs to be called before any devices perform DMA
+	 * operations that might use the SWIOTLB bounce buffers. It will
+	 * mark the bounce buffers as decrypted so that their usage will
+	 * not cause "plain-text" data to be decrypted when accessed. It
+	 * must be called after late_time_init() so that Hyper-V x86/x64
+	 * hypercalls work when the SWIOTLB bounce buffers are decrypted.
+	 */
+	mem_encrypt_init();
+}
diff --git a/arch/x86/kernel/cpu/cpu.h b/arch/x86/kernel/cpu/cpu.h
new file mode 100644
index 0000000000..1dcd7d4e38
--- /dev/null
+++ b/arch/x86/kernel/cpu/cpu.h
@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef ARCH_X86_CPU_H
+#define ARCH_X86_CPU_H
+
+/* attempt to consolidate cpu attributes */
+struct cpu_dev {
+	const char	*c_vendor;
+
+	/* some have two possibilities for cpuid string */
+	const char	*c_ident[2];
+
+	void            (*c_early_init)(struct cpuinfo_x86 *);
+	void		(*c_bsp_init)(struct cpuinfo_x86 *);
+	void		(*c_init)(struct cpuinfo_x86 *);
+	void		(*c_identify)(struct cpuinfo_x86 *);
+	void		(*c_detect_tlb)(struct cpuinfo_x86 *);
+	int		c_x86_vendor;
+#ifdef CONFIG_X86_32
+	/* Optional vendor specific routine to obtain the cache size. */
+	unsigned int	(*legacy_cache_size)(struct cpuinfo_x86 *,
+					     unsigned int);
+
+	/* Family/stepping-based lookup table for model names. */
+	struct legacy_cpu_model_info {
+		int		family;
+		const char	*model_names[16];
+	}		legacy_models[5];
+#endif
+};
+
+struct _tlb_table {
+	unsigned char descriptor;
+	char tlb_type;
+	unsigned int entries;
+	/* unsigned int ways; */
+	char info[128];
+};
+
+#define cpu_dev_register(cpu_devX) \
+	static const struct cpu_dev *const __cpu_dev_##cpu_devX __used \
+	__section(".x86_cpu_dev.init") = \
+	&cpu_devX;
+
+extern const struct cpu_dev *const __x86_cpu_dev_start[],
+			    *const __x86_cpu_dev_end[];
+
+#ifdef CONFIG_CPU_SUP_INTEL
+enum tsx_ctrl_states {
+	TSX_CTRL_ENABLE,
+	TSX_CTRL_DISABLE,
+	TSX_CTRL_RTM_ALWAYS_ABORT,
+	TSX_CTRL_NOT_SUPPORTED,
+};
+
+extern __ro_after_init enum tsx_ctrl_states tsx_ctrl_state;
+
+extern void __init tsx_init(void);
+void tsx_ap_init(void);
+#else
+static inline void tsx_init(void) { }
+static inline void tsx_ap_init(void) { }
+#endif /* CONFIG_CPU_SUP_INTEL */
+
+extern void init_spectral_chicken(struct cpuinfo_x86 *c);
+
+extern void get_cpu_cap(struct cpuinfo_x86 *c);
+extern void get_cpu_address_sizes(struct cpuinfo_x86 *c);
+extern void cpu_detect_cache_sizes(struct cpuinfo_x86 *c);
+extern void init_scattered_cpuid_features(struct cpuinfo_x86 *c);
+extern void init_intel_cacheinfo(struct cpuinfo_x86 *c);
+extern void init_amd_cacheinfo(struct cpuinfo_x86 *c);
+extern void init_hygon_cacheinfo(struct cpuinfo_x86 *c);
+
+extern void detect_num_cpu_cores(struct cpuinfo_x86 *c);
+extern int detect_extended_topology_early(struct cpuinfo_x86 *c);
+extern int detect_extended_topology(struct cpuinfo_x86 *c);
+extern int detect_ht_early(struct cpuinfo_x86 *c);
+extern void detect_ht(struct cpuinfo_x86 *c);
+extern void check_null_seg_clears_base(struct cpuinfo_x86 *c);
+
+unsigned int aperfmperf_get_khz(int cpu);
+void cpu_select_mitigations(void);
+
+extern void x86_spec_ctrl_setup_ap(void);
+extern void update_srbds_msr(void);
+extern void update_gds_msr(void);
+
+extern enum spectre_v2_mitigation spectre_v2_enabled;
+
+static inline bool spectre_v2_in_eibrs_mode(enum spectre_v2_mitigation mode)
+{
+	return mode == SPECTRE_V2_EIBRS ||
+	       mode == SPECTRE_V2_EIBRS_RETPOLINE ||
+	       mode == SPECTRE_V2_EIBRS_LFENCE;
+}
+#endif /* ARCH_X86_CPU_H */
diff --git a/arch/x86/kernel/cpu/cpuid-deps.c b/arch/x86/kernel/cpu/cpuid-deps.c
new file mode 100644
index 0000000000..e462c1d380
--- /dev/null
+++ b/arch/x86/kernel/cpu/cpuid-deps.c
@@ -0,0 +1,144 @@
+/* Declare dependencies between CPUIDs */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <asm/cpufeature.h>
+
+struct cpuid_dep {
+	unsigned int	feature;
+	unsigned int	depends;
+};
+
+/*
+ * Table of CPUID features that depend on others.
+ *
+ * This only includes dependencies that can be usefully disabled, not
+ * features part of the base set (like FPU).
+ *
+ * Note this all is not __init / __initdata because it can be
+ * called from cpu hotplug. It shouldn't do anything in this case,
+ * but it's difficult to tell that to the init reference checker.
+ */
+static const struct cpuid_dep cpuid_deps[] = {
+	{ X86_FEATURE_FXSR,			X86_FEATURE_FPU	      },
+	{ X86_FEATURE_XSAVEOPT,			X86_FEATURE_XSAVE     },
+	{ X86_FEATURE_XSAVEC,			X86_FEATURE_XSAVE     },
+	{ X86_FEATURE_XSAVES,			X86_FEATURE_XSAVE     },
+	{ X86_FEATURE_AVX,			X86_FEATURE_XSAVE     },
+	{ X86_FEATURE_PKU,			X86_FEATURE_XSAVE     },
+	{ X86_FEATURE_MPX,			X86_FEATURE_XSAVE     },
+	{ X86_FEATURE_XGETBV1,			X86_FEATURE_XSAVE     },
+	{ X86_FEATURE_CMOV,			X86_FEATURE_FXSR      },
+	{ X86_FEATURE_MMX,			X86_FEATURE_FXSR      },
+	{ X86_FEATURE_MMXEXT,			X86_FEATURE_MMX       },
+	{ X86_FEATURE_FXSR_OPT,			X86_FEATURE_FXSR      },
+	{ X86_FEATURE_XSAVE,			X86_FEATURE_FXSR      },
+	{ X86_FEATURE_XMM,			X86_FEATURE_FXSR      },
+	{ X86_FEATURE_XMM2,			X86_FEATURE_XMM       },
+	{ X86_FEATURE_XMM3,			X86_FEATURE_XMM2      },
+	{ X86_FEATURE_XMM4_1,			X86_FEATURE_XMM2      },
+	{ X86_FEATURE_XMM4_2,			X86_FEATURE_XMM2      },
+	{ X86_FEATURE_XMM3,			X86_FEATURE_XMM2      },
+	{ X86_FEATURE_PCLMULQDQ,		X86_FEATURE_XMM2      },
+	{ X86_FEATURE_SSSE3,			X86_FEATURE_XMM2,     },
+	{ X86_FEATURE_F16C,			X86_FEATURE_XMM2,     },
+	{ X86_FEATURE_AES,			X86_FEATURE_XMM2      },
+	{ X86_FEATURE_SHA_NI,			X86_FEATURE_XMM2      },
+	{ X86_FEATURE_FMA,			X86_FEATURE_AVX       },
+	{ X86_FEATURE_AVX2,			X86_FEATURE_AVX,      },
+	{ X86_FEATURE_AVX512F,			X86_FEATURE_AVX,      },
+	{ X86_FEATURE_AVX512IFMA,		X86_FEATURE_AVX512F   },
+	{ X86_FEATURE_AVX512PF,			X86_FEATURE_AVX512F   },
+	{ X86_FEATURE_AVX512ER,			X86_FEATURE_AVX512F   },
+	{ X86_FEATURE_AVX512CD,			X86_FEATURE_AVX512F   },
+	{ X86_FEATURE_AVX512DQ,			X86_FEATURE_AVX512F   },
+	{ X86_FEATURE_AVX512BW,			X86_FEATURE_AVX512F   },
+	{ X86_FEATURE_AVX512VL,			X86_FEATURE_AVX512F   },
+	{ X86_FEATURE_AVX512VBMI,		X86_FEATURE_AVX512F   },
+	{ X86_FEATURE_AVX512_VBMI2,		X86_FEATURE_AVX512VL  },
+	{ X86_FEATURE_GFNI,			X86_FEATURE_AVX512VL  },
+	{ X86_FEATURE_VAES,			X86_FEATURE_AVX512VL  },
+	{ X86_FEATURE_VPCLMULQDQ,		X86_FEATURE_AVX512VL  },
+	{ X86_FEATURE_AVX512_VNNI,		X86_FEATURE_AVX512VL  },
+	{ X86_FEATURE_AVX512_BITALG,		X86_FEATURE_AVX512VL  },
+	{ X86_FEATURE_AVX512_4VNNIW,		X86_FEATURE_AVX512F   },
+	{ X86_FEATURE_AVX512_4FMAPS,		X86_FEATURE_AVX512F   },
+	{ X86_FEATURE_AVX512_VPOPCNTDQ,		X86_FEATURE_AVX512F   },
+	{ X86_FEATURE_AVX512_VP2INTERSECT,	X86_FEATURE_AVX512VL  },
+	{ X86_FEATURE_CQM_OCCUP_LLC,		X86_FEATURE_CQM_LLC   },
+	{ X86_FEATURE_CQM_MBM_TOTAL,		X86_FEATURE_CQM_LLC   },
+	{ X86_FEATURE_CQM_MBM_LOCAL,		X86_FEATURE_CQM_LLC   },
+	{ X86_FEATURE_BMEC,			X86_FEATURE_CQM_MBM_TOTAL   },
+	{ X86_FEATURE_BMEC,			X86_FEATURE_CQM_MBM_LOCAL   },
+	{ X86_FEATURE_AVX512_BF16,		X86_FEATURE_AVX512VL  },
+	{ X86_FEATURE_AVX512_FP16,		X86_FEATURE_AVX512BW  },
+	{ X86_FEATURE_ENQCMD,			X86_FEATURE_XSAVES    },
+	{ X86_FEATURE_PER_THREAD_MBA,		X86_FEATURE_MBA       },
+	{ X86_FEATURE_SGX_LC,			X86_FEATURE_SGX	      },
+	{ X86_FEATURE_SGX1,			X86_FEATURE_SGX       },
+	{ X86_FEATURE_SGX2,			X86_FEATURE_SGX1      },
+	{ X86_FEATURE_SGX_EDECCSSA,		X86_FEATURE_SGX1      },
+	{ X86_FEATURE_XFD,			X86_FEATURE_XSAVES    },
+	{ X86_FEATURE_XFD,			X86_FEATURE_XGETBV1   },
+	{ X86_FEATURE_AMX_TILE,			X86_FEATURE_XFD       },
+	{ X86_FEATURE_SHSTK,			X86_FEATURE_XSAVES    },
+	{}
+};
+
+static inline void clear_feature(struct cpuinfo_x86 *c, unsigned int feature)
+{
+	/*
+	 * Note: This could use the non atomic __*_bit() variants, but the
+	 * rest of the cpufeature code uses atomics as well, so keep it for
+	 * consistency. Cleanup all of it separately.
+	 */
+	if (!c) {
+		clear_cpu_cap(&boot_cpu_data, feature);
+		set_bit(feature, (unsigned long *)cpu_caps_cleared);
+	} else {
+		clear_bit(feature, (unsigned long *)c->x86_capability);
+	}
+}
+
+/* Take the capabilities and the BUG bits into account */
+#define MAX_FEATURE_BITS ((NCAPINTS + NBUGINTS) * sizeof(u32) * 8)
+
+static void do_clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
+{
+	DECLARE_BITMAP(disable, MAX_FEATURE_BITS);
+	const struct cpuid_dep *d;
+	bool changed;
+
+	if (WARN_ON(feature >= MAX_FEATURE_BITS))
+		return;
+
+	clear_feature(c, feature);
+
+	/* Collect all features to disable, handling dependencies */
+	memset(disable, 0, sizeof(disable));
+	__set_bit(feature, disable);
+
+	/* Loop until we get a stable state. */
+	do {
+		changed = false;
+		for (d = cpuid_deps; d->feature; d++) {
+			if (!test_bit(d->depends, disable))
+				continue;
+			if (__test_and_set_bit(d->feature, disable))
+				continue;
+
+			changed = true;
+			clear_feature(c, d->feature);
+		}
+	} while (changed);
+}
+
+void clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
+{
+	do_clear_cpu_cap(c, feature);
+}
+
+void setup_clear_cpu_cap(unsigned int feature)
+{
+	do_clear_cpu_cap(NULL, feature);
+}
diff --git a/arch/x86/kernel/cpu/cyrix.c b/arch/x86/kernel/cpu/cyrix.c
new file mode 100644
index 0000000000..9651275aec
--- /dev/null
+++ b/arch/x86/kernel/cpu/cyrix.c
@@ -0,0 +1,467 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/isa-dma.h>
+#include <linux/pci.h>
+#include <asm/dma.h>
+#include <linux/io.h>
+#include <asm/processor-cyrix.h>
+#include <asm/processor-flags.h>
+#include <linux/timer.h>
+#include <asm/pci-direct.h>
+#include <asm/tsc.h>
+#include <asm/cpufeature.h>
+#include <linux/sched.h>
+#include <linux/sched/clock.h>
+
+#include "cpu.h"
+
+/*
+ * Read NSC/Cyrix DEVID registers (DIR) to get more detailed info. about the CPU
+ */
+static void __do_cyrix_devid(unsigned char *dir0, unsigned char *dir1)
+{
+	unsigned char ccr2, ccr3;
+
+	/* we test for DEVID by checking whether CCR3 is writable */
+	ccr3 = getCx86(CX86_CCR3);
+	setCx86(CX86_CCR3, ccr3 ^ 0x80);
+	getCx86(0xc0);   /* dummy to change bus */
+
+	if (getCx86(CX86_CCR3) == ccr3) {       /* no DEVID regs. */
+		ccr2 = getCx86(CX86_CCR2);
+		setCx86(CX86_CCR2, ccr2 ^ 0x04);
+		getCx86(0xc0);  /* dummy */
+
+		if (getCx86(CX86_CCR2) == ccr2) /* old Cx486SLC/DLC */
+			*dir0 = 0xfd;
+		else {                          /* Cx486S A step */
+			setCx86(CX86_CCR2, ccr2);
+			*dir0 = 0xfe;
+		}
+	} else {
+		setCx86(CX86_CCR3, ccr3);  /* restore CCR3 */
+
+		/* read DIR0 and DIR1 CPU registers */
+		*dir0 = getCx86(CX86_DIR0);
+		*dir1 = getCx86(CX86_DIR1);
+	}
+}
+
+static void do_cyrix_devid(unsigned char *dir0, unsigned char *dir1)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	__do_cyrix_devid(dir0, dir1);
+	local_irq_restore(flags);
+}
+/*
+ * Cx86_dir0_msb is a HACK needed by check_cx686_cpuid/slop in bugs.h in
+ * order to identify the Cyrix CPU model after we're out of setup.c
+ *
+ * Actually since bugs.h doesn't even reference this perhaps someone should
+ * fix the documentation ???
+ */
+static unsigned char Cx86_dir0_msb = 0;
+
+static const char Cx86_model[][9] = {
+	"Cx486", "Cx486", "5x86 ", "6x86", "MediaGX ", "6x86MX ",
+	"M II ", "Unknown"
+};
+static const char Cx486_name[][5] = {
+	"SLC", "DLC", "SLC2", "DLC2", "SRx", "DRx",
+	"SRx2", "DRx2"
+};
+static const char Cx486S_name[][4] = {
+	"S", "S2", "Se", "S2e"
+};
+static const char Cx486D_name[][4] = {
+	"DX", "DX2", "?", "?", "?", "DX4"
+};
+static char Cx86_cb[] = "?.5x Core/Bus Clock";
+static const char cyrix_model_mult1[] = "12??43";
+static const char cyrix_model_mult2[] = "12233445";
+
+/*
+ * Reset the slow-loop (SLOP) bit on the 686(L) which is set by some old
+ * BIOSes for compatibility with DOS games.  This makes the udelay loop
+ * work correctly, and improves performance.
+ *
+ * FIXME: our newer udelay uses the tsc. We don't need to frob with SLOP
+ */
+
+static void check_cx686_slop(struct cpuinfo_x86 *c)
+{
+	unsigned long flags;
+
+	if (Cx86_dir0_msb == 3) {
+		unsigned char ccr3, ccr5;
+
+		local_irq_save(flags);
+		ccr3 = getCx86(CX86_CCR3);
+		setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
+		ccr5 = getCx86(CX86_CCR5);
+		if (ccr5 & 2)
+			setCx86(CX86_CCR5, ccr5 & 0xfd);  /* reset SLOP */
+		setCx86(CX86_CCR3, ccr3);                 /* disable MAPEN */
+		local_irq_restore(flags);
+
+		if (ccr5 & 2) { /* possible wrong calibration done */
+			pr_info("Recalibrating delay loop with SLOP bit reset\n");
+			calibrate_delay();
+			c->loops_per_jiffy = loops_per_jiffy;
+		}
+	}
+}
+
+
+static void set_cx86_reorder(void)
+{
+	u8 ccr3;
+
+	pr_info("Enable Memory access reorder on Cyrix/NSC processor.\n");
+	ccr3 = getCx86(CX86_CCR3);
+	setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
+
+	/* Load/Store Serialize to mem access disable (=reorder it) */
+	setCx86(CX86_PCR0, getCx86(CX86_PCR0) & ~0x80);
+	/* set load/store serialize from 1GB to 4GB */
+	ccr3 |= 0xe0;
+	setCx86(CX86_CCR3, ccr3);
+}
+
+static void set_cx86_memwb(void)
+{
+	pr_info("Enable Memory-Write-back mode on Cyrix/NSC processor.\n");
+
+	/* CCR2 bit 2: unlock NW bit */
+	setCx86(CX86_CCR2, getCx86(CX86_CCR2) & ~0x04);
+	/* set 'Not Write-through' */
+	write_cr0(read_cr0() | X86_CR0_NW);
+	/* CCR2 bit 2: lock NW bit and set WT1 */
+	setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x14);
+}
+
+/*
+ *	Configure later MediaGX and/or Geode processor.
+ */
+
+static void geode_configure(void)
+{
+	unsigned long flags;
+	u8 ccr3;
+	local_irq_save(flags);
+
+	/* Suspend on halt power saving and enable #SUSP pin */
+	setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
+
+	ccr3 = getCx86(CX86_CCR3);
+	setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10);	/* enable MAPEN */
+
+
+	/* FPU fast, DTE cache, Mem bypass */
+	setCx86(CX86_CCR4, getCx86(CX86_CCR4) | 0x38);
+	setCx86(CX86_CCR3, ccr3);			/* disable MAPEN */
+
+	set_cx86_memwb();
+	set_cx86_reorder();
+
+	local_irq_restore(flags);
+}
+
+static void early_init_cyrix(struct cpuinfo_x86 *c)
+{
+	unsigned char dir0, dir0_msn, dir1 = 0;
+
+	__do_cyrix_devid(&dir0, &dir1);
+	dir0_msn = dir0 >> 4; /* identifies CPU "family"   */
+
+	switch (dir0_msn) {
+	case 3: /* 6x86/6x86L */
+		/* Emulate MTRRs using Cyrix's ARRs. */
+		set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
+		break;
+	case 5: /* 6x86MX/M II */
+		/* Emulate MTRRs using Cyrix's ARRs. */
+		set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
+		break;
+	}
+}
+
+static void init_cyrix(struct cpuinfo_x86 *c)
+{
+	unsigned char dir0, dir0_msn, dir0_lsn, dir1 = 0;
+	char *buf = c->x86_model_id;
+	const char *p = NULL;
+
+	/*
+	 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
+	 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
+	 */
+	clear_cpu_cap(c, 0*32+31);
+
+	/* Cyrix used bit 24 in extended (AMD) CPUID for Cyrix MMX extensions */
+	if (test_cpu_cap(c, 1*32+24)) {
+		clear_cpu_cap(c, 1*32+24);
+		set_cpu_cap(c, X86_FEATURE_CXMMX);
+	}
+
+	do_cyrix_devid(&dir0, &dir1);
+
+	check_cx686_slop(c);
+
+	Cx86_dir0_msb = dir0_msn = dir0 >> 4; /* identifies CPU "family"   */
+	dir0_lsn = dir0 & 0xf;                /* model or clock multiplier */
+
+	/* common case step number/rev -- exceptions handled below */
+	c->x86_model = (dir1 >> 4) + 1;
+	c->x86_stepping = dir1 & 0xf;
+
+	/* Now cook; the original recipe is by Channing Corn, from Cyrix.
+	 * We do the same thing for each generation: we work out
+	 * the model, multiplier and stepping.  Black magic included,
+	 * to make the silicon step/rev numbers match the printed ones.
+	 */
+
+	switch (dir0_msn) {
+		unsigned char tmp;
+
+	case 0: /* Cx486SLC/DLC/SRx/DRx */
+		p = Cx486_name[dir0_lsn & 7];
+		break;
+
+	case 1: /* Cx486S/DX/DX2/DX4 */
+		p = (dir0_lsn & 8) ? Cx486D_name[dir0_lsn & 5]
+			: Cx486S_name[dir0_lsn & 3];
+		break;
+
+	case 2: /* 5x86 */
+		Cx86_cb[2] = cyrix_model_mult1[dir0_lsn & 5];
+		p = Cx86_cb+2;
+		break;
+
+	case 3: /* 6x86/6x86L */
+		Cx86_cb[1] = ' ';
+		Cx86_cb[2] = cyrix_model_mult1[dir0_lsn & 5];
+		if (dir1 > 0x21) { /* 686L */
+			Cx86_cb[0] = 'L';
+			p = Cx86_cb;
+			(c->x86_model)++;
+		} else             /* 686 */
+			p = Cx86_cb+1;
+		/* Emulate MTRRs using Cyrix's ARRs. */
+		set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
+		/* 6x86's contain this bug */
+		set_cpu_bug(c, X86_BUG_COMA);
+		break;
+
+	case 4: /* MediaGX/GXm or Geode GXM/GXLV/GX1 */
+	case 11: /* GX1 with inverted Device ID */
+#ifdef CONFIG_PCI
+	{
+		u32 vendor, device;
+		/*
+		 * It isn't really a PCI quirk directly, but the cure is the
+		 * same. The MediaGX has deep magic SMM stuff that handles the
+		 * SB emulation. It throws away the fifo on disable_dma() which
+		 * is wrong and ruins the audio.
+		 *
+		 *  Bug2: VSA1 has a wrap bug so that using maximum sized DMA
+		 *  causes bad things. According to NatSemi VSA2 has another
+		 *  bug to do with 'hlt'. I've not seen any boards using VSA2
+		 *  and X doesn't seem to support it either so who cares 8).
+		 *  VSA1 we work around however.
+		 */
+
+		pr_info("Working around Cyrix MediaGX virtual DMA bugs.\n");
+		isa_dma_bridge_buggy = 2;
+
+		/* We do this before the PCI layer is running. However we
+		   are safe here as we know the bridge must be a Cyrix
+		   companion and must be present */
+		vendor = read_pci_config_16(0, 0, 0x12, PCI_VENDOR_ID);
+		device = read_pci_config_16(0, 0, 0x12, PCI_DEVICE_ID);
+
+		/*
+		 *  The 5510/5520 companion chips have a funky PIT.
+		 */
+		if (vendor == PCI_VENDOR_ID_CYRIX &&
+			(device == PCI_DEVICE_ID_CYRIX_5510 ||
+					device == PCI_DEVICE_ID_CYRIX_5520))
+			mark_tsc_unstable("cyrix 5510/5520 detected");
+	}
+#endif
+		c->x86_cache_size = 16;	/* Yep 16K integrated cache that's it */
+
+		/* GXm supports extended cpuid levels 'ala' AMD */
+		if (c->cpuid_level == 2) {
+			/* Enable cxMMX extensions (GX1 Datasheet 54) */
+			setCx86(CX86_CCR7, getCx86(CX86_CCR7) | 1);
+
+			/*
+			 * GXm : 0x30 ... 0x5f GXm  datasheet 51
+			 * GXlv: 0x6x          GXlv datasheet 54
+			 *  ?  : 0x7x
+			 * GX1 : 0x8x          GX1  datasheet 56
+			 */
+			if ((0x30 <= dir1 && dir1 <= 0x6f) ||
+					(0x80 <= dir1 && dir1 <= 0x8f))
+				geode_configure();
+			return;
+		} else { /* MediaGX */
+			Cx86_cb[2] = (dir0_lsn & 1) ? '3' : '4';
+			p = Cx86_cb+2;
+			c->x86_model = (dir1 & 0x20) ? 1 : 2;
+		}
+		break;
+
+	case 5: /* 6x86MX/M II */
+		if (dir1 > 7) {
+			dir0_msn++;  /* M II */
+			/* Enable MMX extensions (App note 108) */
+			setCx86(CX86_CCR7, getCx86(CX86_CCR7)|1);
+		} else {
+			/* A 6x86MX - it has the bug. */
+			set_cpu_bug(c, X86_BUG_COMA);
+		}
+		tmp = (!(dir0_lsn & 7) || dir0_lsn & 1) ? 2 : 0;
+		Cx86_cb[tmp] = cyrix_model_mult2[dir0_lsn & 7];
+		p = Cx86_cb+tmp;
+		if (((dir1 & 0x0f) > 4) || ((dir1 & 0xf0) == 0x20))
+			(c->x86_model)++;
+		/* Emulate MTRRs using Cyrix's ARRs. */
+		set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
+		break;
+
+	case 0xf:  /* Cyrix 486 without DEVID registers */
+		switch (dir0_lsn) {
+		case 0xd:  /* either a 486SLC or DLC w/o DEVID */
+			dir0_msn = 0;
+			p = Cx486_name[!!boot_cpu_has(X86_FEATURE_FPU)];
+			break;
+
+		case 0xe:  /* a 486S A step */
+			dir0_msn = 0;
+			p = Cx486S_name[0];
+			break;
+		}
+		break;
+
+	default:  /* unknown (shouldn't happen, we know everyone ;-) */
+		dir0_msn = 7;
+		break;
+	}
+	strcpy(buf, Cx86_model[dir0_msn & 7]);
+	if (p)
+		strcat(buf, p);
+	return;
+}
+
+/*
+ * Handle National Semiconductor branded processors
+ */
+static void init_nsc(struct cpuinfo_x86 *c)
+{
+	/*
+	 * There may be GX1 processors in the wild that are branded
+	 * NSC and not Cyrix.
+	 *
+	 * This function only handles the GX processor, and kicks every
+	 * thing else to the Cyrix init function above - that should
+	 * cover any processors that might have been branded differently
+	 * after NSC acquired Cyrix.
+	 *
+	 * If this breaks your GX1 horribly, please e-mail
+	 * info-linux@ldcmail.amd.com to tell us.
+	 */
+
+	/* Handle the GX (Formally known as the GX2) */
+
+	if (c->x86 == 5 && c->x86_model == 5)
+		cpu_detect_cache_sizes(c);
+	else
+		init_cyrix(c);
+}
+
+/*
+ * Cyrix CPUs without cpuid or with cpuid not yet enabled can be detected
+ * by the fact that they preserve the flags across the division of 5/2.
+ * PII and PPro exhibit this behavior too, but they have cpuid available.
+ */
+
+/*
+ * Perform the Cyrix 5/2 test. A Cyrix won't change
+ * the flags, while other 486 chips will.
+ */
+static inline int test_cyrix_52div(void)
+{
+	unsigned int test;
+
+	__asm__ __volatile__(
+	     "sahf\n\t"		/* clear flags (%eax = 0x0005) */
+	     "div %b2\n\t"	/* divide 5 by 2 */
+	     "lahf"		/* store flags into %ah */
+	     : "=a" (test)
+	     : "0" (5), "q" (2)
+	     : "cc");
+
+	/* AH is 0x02 on Cyrix after the divide.. */
+	return (unsigned char) (test >> 8) == 0x02;
+}
+
+static void cyrix_identify(struct cpuinfo_x86 *c)
+{
+	/* Detect Cyrix with disabled CPUID */
+	if (c->x86 == 4 && test_cyrix_52div()) {
+		unsigned char dir0, dir1;
+
+		strcpy(c->x86_vendor_id, "CyrixInstead");
+		c->x86_vendor = X86_VENDOR_CYRIX;
+
+		/* Actually enable cpuid on the older cyrix */
+
+		/* Retrieve CPU revisions */
+
+		do_cyrix_devid(&dir0, &dir1);
+
+		dir0 >>= 4;
+
+		/* Check it is an affected model */
+
+		if (dir0 == 5 || dir0 == 3) {
+			unsigned char ccr3;
+			unsigned long flags;
+			pr_info("Enabling CPUID on Cyrix processor.\n");
+			local_irq_save(flags);
+			ccr3 = getCx86(CX86_CCR3);
+			/* enable MAPEN  */
+			setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10);
+			/* enable cpuid  */
+			setCx86(CX86_CCR4, getCx86(CX86_CCR4) | 0x80);
+			/* disable MAPEN */
+			setCx86(CX86_CCR3, ccr3);
+			local_irq_restore(flags);
+		}
+	}
+}
+
+static const struct cpu_dev cyrix_cpu_dev = {
+	.c_vendor	= "Cyrix",
+	.c_ident	= { "CyrixInstead" },
+	.c_early_init	= early_init_cyrix,
+	.c_init		= init_cyrix,
+	.c_identify	= cyrix_identify,
+	.c_x86_vendor	= X86_VENDOR_CYRIX,
+};
+
+cpu_dev_register(cyrix_cpu_dev);
+
+static const struct cpu_dev nsc_cpu_dev = {
+	.c_vendor	= "NSC",
+	.c_ident	= { "Geode by NSC" },
+	.c_init		= init_nsc,
+	.c_x86_vendor	= X86_VENDOR_NSC,
+};
+
+cpu_dev_register(nsc_cpu_dev);
diff --git a/arch/x86/kernel/cpu/feat_ctl.c b/arch/x86/kernel/cpu/feat_ctl.c
new file mode 100644
index 0000000000..03851240c3
--- /dev/null
+++ b/arch/x86/kernel/cpu/feat_ctl.c
@@ -0,0 +1,212 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/tboot.h>
+
+#include <asm/cpu.h>
+#include <asm/cpufeature.h>
+#include <asm/msr-index.h>
+#include <asm/processor.h>
+#include <asm/vmx.h>
+
+#undef pr_fmt
+#define pr_fmt(fmt)	"x86/cpu: " fmt
+
+#ifdef CONFIG_X86_VMX_FEATURE_NAMES
+enum vmx_feature_leafs {
+	MISC_FEATURES = 0,
+	PRIMARY_CTLS,
+	SECONDARY_CTLS,
+	TERTIARY_CTLS_LOW,
+	TERTIARY_CTLS_HIGH,
+	NR_VMX_FEATURE_WORDS,
+};
+
+#define VMX_F(x) BIT(VMX_FEATURE_##x & 0x1f)
+
+static void init_vmx_capabilities(struct cpuinfo_x86 *c)
+{
+	u32 supported, funcs, ept, vpid, ign, low, high;
+
+	BUILD_BUG_ON(NVMXINTS != NR_VMX_FEATURE_WORDS);
+
+	/*
+	 * The high bits contain the allowed-1 settings, i.e. features that can
+	 * be turned on.  The low bits contain the allowed-0 settings, i.e.
+	 * features that can be turned off.  Ignore the allowed-0 settings,
+	 * if a feature can be turned on then it's supported.
+	 *
+	 * Use raw rdmsr() for primary processor controls and pin controls MSRs
+	 * as they exist on any CPU that supports VMX, i.e. we want the WARN if
+	 * the RDMSR faults.
+	 */
+	rdmsr(MSR_IA32_VMX_PROCBASED_CTLS, ign, supported);
+	c->vmx_capability[PRIMARY_CTLS] = supported;
+
+	rdmsr_safe(MSR_IA32_VMX_PROCBASED_CTLS2, &ign, &supported);
+	c->vmx_capability[SECONDARY_CTLS] = supported;
+
+	/* All 64 bits of tertiary controls MSR are allowed-1 settings. */
+	rdmsr_safe(MSR_IA32_VMX_PROCBASED_CTLS3, &low, &high);
+	c->vmx_capability[TERTIARY_CTLS_LOW] = low;
+	c->vmx_capability[TERTIARY_CTLS_HIGH] = high;
+
+	rdmsr(MSR_IA32_VMX_PINBASED_CTLS, ign, supported);
+	rdmsr_safe(MSR_IA32_VMX_VMFUNC, &ign, &funcs);
+
+	/*
+	 * Except for EPT+VPID, which enumerates support for both in a single
+	 * MSR, low for EPT, high for VPID.
+	 */
+	rdmsr_safe(MSR_IA32_VMX_EPT_VPID_CAP, &ept, &vpid);
+
+	/* Pin, EPT, VPID and VM-Func are merged into a single word. */
+	WARN_ON_ONCE(supported >> 16);
+	WARN_ON_ONCE(funcs >> 4);
+	c->vmx_capability[MISC_FEATURES] = (supported & 0xffff) |
+					   ((vpid & 0x1) << 16) |
+					   ((funcs & 0xf) << 28);
+
+	/* EPT bits are full on scattered and must be manually handled. */
+	if (ept & VMX_EPT_EXECUTE_ONLY_BIT)
+		c->vmx_capability[MISC_FEATURES] |= VMX_F(EPT_EXECUTE_ONLY);
+	if (ept & VMX_EPT_AD_BIT)
+		c->vmx_capability[MISC_FEATURES] |= VMX_F(EPT_AD);
+	if (ept & VMX_EPT_1GB_PAGE_BIT)
+		c->vmx_capability[MISC_FEATURES] |= VMX_F(EPT_1GB);
+
+	/* Synthetic APIC features that are aggregates of multiple features. */
+	if ((c->vmx_capability[PRIMARY_CTLS] & VMX_F(VIRTUAL_TPR)) &&
+	    (c->vmx_capability[SECONDARY_CTLS] & VMX_F(VIRT_APIC_ACCESSES)))
+		c->vmx_capability[MISC_FEATURES] |= VMX_F(FLEXPRIORITY);
+
+	if ((c->vmx_capability[PRIMARY_CTLS] & VMX_F(VIRTUAL_TPR)) &&
+	    (c->vmx_capability[SECONDARY_CTLS] & VMX_F(APIC_REGISTER_VIRT)) &&
+	    (c->vmx_capability[SECONDARY_CTLS] & VMX_F(VIRT_INTR_DELIVERY)) &&
+	    (c->vmx_capability[MISC_FEATURES] & VMX_F(POSTED_INTR)))
+		c->vmx_capability[MISC_FEATURES] |= VMX_F(APICV);
+
+	/* Set the synthetic cpufeatures to preserve /proc/cpuinfo's ABI. */
+	if (c->vmx_capability[PRIMARY_CTLS] & VMX_F(VIRTUAL_TPR))
+		set_cpu_cap(c, X86_FEATURE_TPR_SHADOW);
+	if (c->vmx_capability[MISC_FEATURES] & VMX_F(FLEXPRIORITY))
+		set_cpu_cap(c, X86_FEATURE_FLEXPRIORITY);
+	if (c->vmx_capability[MISC_FEATURES] & VMX_F(VIRTUAL_NMIS))
+		set_cpu_cap(c, X86_FEATURE_VNMI);
+	if (c->vmx_capability[SECONDARY_CTLS] & VMX_F(EPT))
+		set_cpu_cap(c, X86_FEATURE_EPT);
+	if (c->vmx_capability[MISC_FEATURES] & VMX_F(EPT_AD))
+		set_cpu_cap(c, X86_FEATURE_EPT_AD);
+	if (c->vmx_capability[MISC_FEATURES] & VMX_F(VPID))
+		set_cpu_cap(c, X86_FEATURE_VPID);
+}
+#endif /* CONFIG_X86_VMX_FEATURE_NAMES */
+
+static int __init nosgx(char *str)
+{
+	setup_clear_cpu_cap(X86_FEATURE_SGX);
+
+	return 0;
+}
+
+early_param("nosgx", nosgx);
+
+void init_ia32_feat_ctl(struct cpuinfo_x86 *c)
+{
+	bool enable_sgx_kvm = false, enable_sgx_driver = false;
+	bool tboot = tboot_enabled();
+	bool enable_vmx;
+	u64 msr;
+
+	if (rdmsrl_safe(MSR_IA32_FEAT_CTL, &msr)) {
+		clear_cpu_cap(c, X86_FEATURE_VMX);
+		clear_cpu_cap(c, X86_FEATURE_SGX);
+		return;
+	}
+
+	enable_vmx = cpu_has(c, X86_FEATURE_VMX) &&
+		     IS_ENABLED(CONFIG_KVM_INTEL);
+
+	if (cpu_has(c, X86_FEATURE_SGX) && IS_ENABLED(CONFIG_X86_SGX)) {
+		/*
+		 * Separate out SGX driver enabling from KVM.  This allows KVM
+		 * guests to use SGX even if the kernel SGX driver refuses to
+		 * use it.  This happens if flexible Launch Control is not
+		 * available.
+		 */
+		enable_sgx_driver = cpu_has(c, X86_FEATURE_SGX_LC);
+		enable_sgx_kvm = enable_vmx && IS_ENABLED(CONFIG_X86_SGX_KVM);
+	}
+
+	if (msr & FEAT_CTL_LOCKED)
+		goto update_caps;
+
+	/*
+	 * Ignore whatever value BIOS left in the MSR to avoid enabling random
+	 * features or faulting on the WRMSR.
+	 */
+	msr = FEAT_CTL_LOCKED;
+
+	/*
+	 * Enable VMX if and only if the kernel may do VMXON at some point,
+	 * i.e. KVM is enabled, to avoid unnecessarily adding an attack vector
+	 * for the kernel, e.g. using VMX to hide malicious code.
+	 */
+	if (enable_vmx) {
+		msr |= FEAT_CTL_VMX_ENABLED_OUTSIDE_SMX;
+
+		if (tboot)
+			msr |= FEAT_CTL_VMX_ENABLED_INSIDE_SMX;
+	}
+
+	if (enable_sgx_kvm || enable_sgx_driver) {
+		msr |= FEAT_CTL_SGX_ENABLED;
+		if (enable_sgx_driver)
+			msr |= FEAT_CTL_SGX_LC_ENABLED;
+	}
+
+	wrmsrl(MSR_IA32_FEAT_CTL, msr);
+
+update_caps:
+	set_cpu_cap(c, X86_FEATURE_MSR_IA32_FEAT_CTL);
+
+	if (!cpu_has(c, X86_FEATURE_VMX))
+		goto update_sgx;
+
+	if ( (tboot && !(msr & FEAT_CTL_VMX_ENABLED_INSIDE_SMX)) ||
+	    (!tboot && !(msr & FEAT_CTL_VMX_ENABLED_OUTSIDE_SMX))) {
+		if (IS_ENABLED(CONFIG_KVM_INTEL))
+			pr_err_once("VMX (%s TXT) disabled by BIOS\n",
+				    tboot ? "inside" : "outside");
+		clear_cpu_cap(c, X86_FEATURE_VMX);
+	} else {
+#ifdef CONFIG_X86_VMX_FEATURE_NAMES
+		init_vmx_capabilities(c);
+#endif
+	}
+
+update_sgx:
+	if (!(msr & FEAT_CTL_SGX_ENABLED)) {
+		if (enable_sgx_kvm || enable_sgx_driver)
+			pr_err_once("SGX disabled by BIOS.\n");
+		clear_cpu_cap(c, X86_FEATURE_SGX);
+		return;
+	}
+
+	/*
+	 * VMX feature bit may be cleared due to being disabled in BIOS,
+	 * in which case SGX virtualization cannot be supported either.
+	 */
+	if (!cpu_has(c, X86_FEATURE_VMX) && enable_sgx_kvm) {
+		pr_err_once("SGX virtualization disabled due to lack of VMX.\n");
+		enable_sgx_kvm = 0;
+	}
+
+	if (!(msr & FEAT_CTL_SGX_LC_ENABLED) && enable_sgx_driver) {
+		if (!enable_sgx_kvm) {
+			pr_err_once("SGX Launch Control is locked. Disable SGX.\n");
+			clear_cpu_cap(c, X86_FEATURE_SGX);
+		} else {
+			pr_err_once("SGX Launch Control is locked. Support SGX virtualization only.\n");
+			clear_cpu_cap(c, X86_FEATURE_SGX_LC);
+		}
+	}
+}
diff --git a/arch/x86/kernel/cpu/hygon.c b/arch/x86/kernel/cpu/hygon.c
new file mode 100644
index 0000000000..a7b3ef4c4d
--- /dev/null
+++ b/arch/x86/kernel/cpu/hygon.c
@@ -0,0 +1,395 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Hygon Processor Support for Linux
+ *
+ * Copyright (C) 2018 Chengdu Haiguang IC Design Co., Ltd.
+ *
+ * Author: Pu Wen <puwen@hygon.cn>
+ */
+#include <linux/io.h>
+
+#include <asm/apic.h>
+#include <asm/cpu.h>
+#include <asm/smp.h>
+#include <asm/numa.h>
+#include <asm/cacheinfo.h>
+#include <asm/spec-ctrl.h>
+#include <asm/delay.h>
+
+#include "cpu.h"
+
+#define APICID_SOCKET_ID_BIT 6
+
+/*
+ * nodes_per_socket: Stores the number of nodes per socket.
+ * Refer to CPUID Fn8000_001E_ECX Node Identifiers[10:8]
+ */
+static u32 nodes_per_socket = 1;
+
+#ifdef CONFIG_NUMA
+/*
+ * To workaround broken NUMA config.  Read the comment in
+ * srat_detect_node().
+ */
+static int nearby_node(int apicid)
+{
+	int i, node;
+
+	for (i = apicid - 1; i >= 0; i--) {
+		node = __apicid_to_node[i];
+		if (node != NUMA_NO_NODE && node_online(node))
+			return node;
+	}
+	for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
+		node = __apicid_to_node[i];
+		if (node != NUMA_NO_NODE && node_online(node))
+			return node;
+	}
+	return first_node(node_online_map); /* Shouldn't happen */
+}
+#endif
+
+static void hygon_get_topology_early(struct cpuinfo_x86 *c)
+{
+	if (cpu_has(c, X86_FEATURE_TOPOEXT))
+		smp_num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1;
+}
+
+/*
+ * Fixup core topology information for
+ * (1) Hygon multi-node processors
+ *     Assumption: Number of cores in each internal node is the same.
+ * (2) Hygon processors supporting compute units
+ */
+static void hygon_get_topology(struct cpuinfo_x86 *c)
+{
+	int cpu = smp_processor_id();
+
+	/* get information required for multi-node processors */
+	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
+		int err;
+		u32 eax, ebx, ecx, edx;
+
+		cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
+
+		c->cpu_die_id  = ecx & 0xff;
+
+		c->cpu_core_id = ebx & 0xff;
+
+		if (smp_num_siblings > 1)
+			c->x86_max_cores /= smp_num_siblings;
+
+		/*
+		 * In case leaf B is available, use it to derive
+		 * topology information.
+		 */
+		err = detect_extended_topology(c);
+		if (!err)
+			c->x86_coreid_bits = get_count_order(c->x86_max_cores);
+
+		/*
+		 * Socket ID is ApicId[6] for the processors with model <= 0x3
+		 * when running on host.
+		 */
+		if (!boot_cpu_has(X86_FEATURE_HYPERVISOR) && c->x86_model <= 0x3)
+			c->phys_proc_id = c->apicid >> APICID_SOCKET_ID_BIT;
+
+		cacheinfo_hygon_init_llc_id(c, cpu);
+	} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
+		u64 value;
+
+		rdmsrl(MSR_FAM10H_NODE_ID, value);
+		c->cpu_die_id = value & 7;
+
+		per_cpu(cpu_llc_id, cpu) = c->cpu_die_id;
+	} else
+		return;
+
+	if (nodes_per_socket > 1)
+		set_cpu_cap(c, X86_FEATURE_AMD_DCM);
+}
+
+/*
+ * On Hygon setup the lower bits of the APIC id distinguish the cores.
+ * Assumes number of cores is a power of two.
+ */
+static void hygon_detect_cmp(struct cpuinfo_x86 *c)
+{
+	unsigned int bits;
+	int cpu = smp_processor_id();
+
+	bits = c->x86_coreid_bits;
+	/* Low order bits define the core id (index of core in socket) */
+	c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
+	/* Convert the initial APIC ID into the socket ID */
+	c->phys_proc_id = c->initial_apicid >> bits;
+	/* use socket ID also for last level cache */
+	per_cpu(cpu_llc_id, cpu) = c->cpu_die_id = c->phys_proc_id;
+}
+
+static void srat_detect_node(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_NUMA
+	int cpu = smp_processor_id();
+	int node;
+	unsigned int apicid = c->apicid;
+
+	node = numa_cpu_node(cpu);
+	if (node == NUMA_NO_NODE)
+		node = per_cpu(cpu_llc_id, cpu);
+
+	/*
+	 * On multi-fabric platform (e.g. Numascale NumaChip) a
+	 * platform-specific handler needs to be called to fixup some
+	 * IDs of the CPU.
+	 */
+	if (x86_cpuinit.fixup_cpu_id)
+		x86_cpuinit.fixup_cpu_id(c, node);
+
+	if (!node_online(node)) {
+		/*
+		 * Two possibilities here:
+		 *
+		 * - The CPU is missing memory and no node was created.  In
+		 *   that case try picking one from a nearby CPU.
+		 *
+		 * - The APIC IDs differ from the HyperTransport node IDs.
+		 *   Assume they are all increased by a constant offset, but
+		 *   in the same order as the HT nodeids.  If that doesn't
+		 *   result in a usable node fall back to the path for the
+		 *   previous case.
+		 *
+		 * This workaround operates directly on the mapping between
+		 * APIC ID and NUMA node, assuming certain relationship
+		 * between APIC ID, HT node ID and NUMA topology.  As going
+		 * through CPU mapping may alter the outcome, directly
+		 * access __apicid_to_node[].
+		 */
+		int ht_nodeid = c->initial_apicid;
+
+		if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
+			node = __apicid_to_node[ht_nodeid];
+		/* Pick a nearby node */
+		if (!node_online(node))
+			node = nearby_node(apicid);
+	}
+	numa_set_node(cpu, node);
+#endif
+}
+
+static void early_init_hygon_mc(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_SMP
+	unsigned int bits, ecx;
+
+	/* Multi core CPU? */
+	if (c->extended_cpuid_level < 0x80000008)
+		return;
+
+	ecx = cpuid_ecx(0x80000008);
+
+	c->x86_max_cores = (ecx & 0xff) + 1;
+
+	/* CPU telling us the core id bits shift? */
+	bits = (ecx >> 12) & 0xF;
+
+	/* Otherwise recompute */
+	if (bits == 0) {
+		while ((1 << bits) < c->x86_max_cores)
+			bits++;
+	}
+
+	c->x86_coreid_bits = bits;
+#endif
+}
+
+static void bsp_init_hygon(struct cpuinfo_x86 *c)
+{
+	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
+		u64 val;
+
+		rdmsrl(MSR_K7_HWCR, val);
+		if (!(val & BIT(24)))
+			pr_warn(FW_BUG "TSC doesn't count with P0 frequency!\n");
+	}
+
+	if (cpu_has(c, X86_FEATURE_MWAITX))
+		use_mwaitx_delay();
+
+	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
+		u32 ecx;
+
+		ecx = cpuid_ecx(0x8000001e);
+		__max_die_per_package = nodes_per_socket = ((ecx >> 8) & 7) + 1;
+	} else if (boot_cpu_has(X86_FEATURE_NODEID_MSR)) {
+		u64 value;
+
+		rdmsrl(MSR_FAM10H_NODE_ID, value);
+		__max_die_per_package = nodes_per_socket = ((value >> 3) & 7) + 1;
+	}
+
+	if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&
+	    !boot_cpu_has(X86_FEATURE_VIRT_SSBD)) {
+		/*
+		 * Try to cache the base value so further operations can
+		 * avoid RMW. If that faults, do not enable SSBD.
+		 */
+		if (!rdmsrl_safe(MSR_AMD64_LS_CFG, &x86_amd_ls_cfg_base)) {
+			setup_force_cpu_cap(X86_FEATURE_LS_CFG_SSBD);
+			setup_force_cpu_cap(X86_FEATURE_SSBD);
+			x86_amd_ls_cfg_ssbd_mask = 1ULL << 10;
+		}
+	}
+}
+
+static void early_init_hygon(struct cpuinfo_x86 *c)
+{
+	u32 dummy;
+
+	early_init_hygon_mc(c);
+
+	set_cpu_cap(c, X86_FEATURE_K8);
+
+	rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
+
+	/*
+	 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
+	 * with P/T states and does not stop in deep C-states
+	 */
+	if (c->x86_power & (1 << 8)) {
+		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
+		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
+	}
+
+	/* Bit 12 of 8000_0007 edx is accumulated power mechanism. */
+	if (c->x86_power & BIT(12))
+		set_cpu_cap(c, X86_FEATURE_ACC_POWER);
+
+	/* Bit 14 indicates the Runtime Average Power Limit interface. */
+	if (c->x86_power & BIT(14))
+		set_cpu_cap(c, X86_FEATURE_RAPL);
+
+#ifdef CONFIG_X86_64
+	set_cpu_cap(c, X86_FEATURE_SYSCALL32);
+#endif
+
+#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
+	/*
+	 * ApicID can always be treated as an 8-bit value for Hygon APIC So, we
+	 * can safely set X86_FEATURE_EXTD_APICID unconditionally.
+	 */
+	if (boot_cpu_has(X86_FEATURE_APIC))
+		set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
+#endif
+
+	/*
+	 * This is only needed to tell the kernel whether to use VMCALL
+	 * and VMMCALL.  VMMCALL is never executed except under virt, so
+	 * we can set it unconditionally.
+	 */
+	set_cpu_cap(c, X86_FEATURE_VMMCALL);
+
+	hygon_get_topology_early(c);
+}
+
+static void init_hygon(struct cpuinfo_x86 *c)
+{
+	early_init_hygon(c);
+
+	/*
+	 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
+	 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
+	 */
+	clear_cpu_cap(c, 0*32+31);
+
+	set_cpu_cap(c, X86_FEATURE_REP_GOOD);
+
+	/* get apicid instead of initial apic id from cpuid */
+	c->apicid = read_apic_id();
+
+	/*
+	 * XXX someone from Hygon needs to confirm this DTRT
+	 *
+	init_spectral_chicken(c);
+	 */
+
+	set_cpu_cap(c, X86_FEATURE_ZEN);
+	set_cpu_cap(c, X86_FEATURE_CPB);
+
+	cpu_detect_cache_sizes(c);
+
+	hygon_detect_cmp(c);
+	hygon_get_topology(c);
+	srat_detect_node(c);
+
+	init_hygon_cacheinfo(c);
+
+	if (cpu_has(c, X86_FEATURE_XMM2)) {
+		/*
+		 * Use LFENCE for execution serialization.  On families which
+		 * don't have that MSR, LFENCE is already serializing.
+		 * msr_set_bit() uses the safe accessors, too, even if the MSR
+		 * is not present.
+		 */
+		msr_set_bit(MSR_AMD64_DE_CFG,
+			    MSR_AMD64_DE_CFG_LFENCE_SERIALIZE_BIT);
+
+		/* A serializing LFENCE stops RDTSC speculation */
+		set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
+	}
+
+	/*
+	 * Hygon processors have APIC timer running in deep C states.
+	 */
+	set_cpu_cap(c, X86_FEATURE_ARAT);
+
+	/* Hygon CPUs don't reset SS attributes on SYSRET, Xen does. */
+	if (!cpu_feature_enabled(X86_FEATURE_XENPV))
+		set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
+
+	check_null_seg_clears_base(c);
+}
+
+static void cpu_detect_tlb_hygon(struct cpuinfo_x86 *c)
+{
+	u32 ebx, eax, ecx, edx;
+	u16 mask = 0xfff;
+
+	if (c->extended_cpuid_level < 0x80000006)
+		return;
+
+	cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
+
+	tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
+	tlb_lli_4k[ENTRIES] = ebx & mask;
+
+	/* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
+	if (!((eax >> 16) & mask))
+		tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff;
+	else
+		tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
+
+	/* a 4M entry uses two 2M entries */
+	tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
+
+	/* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
+	if (!(eax & mask)) {
+		cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
+		tlb_lli_2m[ENTRIES] = eax & 0xff;
+	} else
+		tlb_lli_2m[ENTRIES] = eax & mask;
+
+	tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
+}
+
+static const struct cpu_dev hygon_cpu_dev = {
+	.c_vendor	= "Hygon",
+	.c_ident	= { "HygonGenuine" },
+	.c_early_init   = early_init_hygon,
+	.c_detect_tlb	= cpu_detect_tlb_hygon,
+	.c_bsp_init	= bsp_init_hygon,
+	.c_init		= init_hygon,
+	.c_x86_vendor	= X86_VENDOR_HYGON,
+};
+
+cpu_dev_register(hygon_cpu_dev);
diff --git a/arch/x86/kernel/cpu/hypervisor.c b/arch/x86/kernel/cpu/hypervisor.c
new file mode 100644
index 0000000000..553bfbfc3a
--- /dev/null
+++ b/arch/x86/kernel/cpu/hypervisor.c
@@ -0,0 +1,109 @@
+/*
+ * Common hypervisor code
+ *
+ * Copyright (C) 2008, VMware, Inc.
+ * Author : Alok N Kataria <akataria@vmware.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/export.h>
+#include <asm/processor.h>
+#include <asm/hypervisor.h>
+
+static const __initconst struct hypervisor_x86 * const hypervisors[] =
+{
+#ifdef CONFIG_XEN_PV
+	&x86_hyper_xen_pv,
+#endif
+#ifdef CONFIG_XEN_PVHVM
+	&x86_hyper_xen_hvm,
+#endif
+	&x86_hyper_vmware,
+	&x86_hyper_ms_hyperv,
+#ifdef CONFIG_KVM_GUEST
+	&x86_hyper_kvm,
+#endif
+#ifdef CONFIG_JAILHOUSE_GUEST
+	&x86_hyper_jailhouse,
+#endif
+#ifdef CONFIG_ACRN_GUEST
+	&x86_hyper_acrn,
+#endif
+};
+
+enum x86_hypervisor_type x86_hyper_type;
+EXPORT_SYMBOL(x86_hyper_type);
+
+bool __initdata nopv;
+static __init int parse_nopv(char *arg)
+{
+	nopv = true;
+	return 0;
+}
+early_param("nopv", parse_nopv);
+
+static inline const struct hypervisor_x86 * __init
+detect_hypervisor_vendor(void)
+{
+	const struct hypervisor_x86 *h = NULL, * const *p;
+	uint32_t pri, max_pri = 0;
+
+	for (p = hypervisors; p < hypervisors + ARRAY_SIZE(hypervisors); p++) {
+		if (unlikely(nopv) && !(*p)->ignore_nopv)
+			continue;
+
+		pri = (*p)->detect();
+		if (pri > max_pri) {
+			max_pri = pri;
+			h = *p;
+		}
+	}
+
+	if (h)
+		pr_info("Hypervisor detected: %s\n", h->name);
+
+	return h;
+}
+
+static void __init copy_array(const void *src, void *target, unsigned int size)
+{
+	unsigned int i, n = size / sizeof(void *);
+	const void * const *from = (const void * const *)src;
+	const void **to = (const void **)target;
+
+	for (i = 0; i < n; i++)
+		if (from[i])
+			to[i] = from[i];
+}
+
+void __init init_hypervisor_platform(void)
+{
+	const struct hypervisor_x86 *h;
+
+	h = detect_hypervisor_vendor();
+
+	if (!h)
+		return;
+
+	copy_array(&h->init, &x86_init.hyper, sizeof(h->init));
+	copy_array(&h->runtime, &x86_platform.hyper, sizeof(h->runtime));
+
+	x86_hyper_type = h->type;
+	x86_init.hyper.init_platform();
+}
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
new file mode 100644
index 0000000000..be4045628f
--- /dev/null
+++ b/arch/x86/kernel/cpu/intel.c
@@ -0,0 +1,1380 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <linux/pgtable.h>
+
+#include <linux/string.h>
+#include <linux/bitops.h>
+#include <linux/smp.h>
+#include <linux/sched.h>
+#include <linux/sched/clock.h>
+#include <linux/semaphore.h>
+#include <linux/thread_info.h>
+#include <linux/init.h>
+#include <linux/uaccess.h>
+#include <linux/workqueue.h>
+#include <linux/delay.h>
+#include <linux/cpuhotplug.h>
+
+#include <asm/cpufeature.h>
+#include <asm/msr.h>
+#include <asm/bugs.h>
+#include <asm/cpu.h>
+#include <asm/intel-family.h>
+#include <asm/microcode.h>
+#include <asm/hwcap2.h>
+#include <asm/elf.h>
+#include <asm/cpu_device_id.h>
+#include <asm/cmdline.h>
+#include <asm/traps.h>
+#include <asm/resctrl.h>
+#include <asm/numa.h>
+#include <asm/thermal.h>
+
+#ifdef CONFIG_X86_64
+#include <linux/topology.h>
+#endif
+
+#include "cpu.h"
+
+#ifdef CONFIG_X86_LOCAL_APIC
+#include <asm/mpspec.h>
+#include <asm/apic.h>
+#endif
+
+enum split_lock_detect_state {
+	sld_off = 0,
+	sld_warn,
+	sld_fatal,
+	sld_ratelimit,
+};
+
+/*
+ * Default to sld_off because most systems do not support split lock detection.
+ * sld_state_setup() will switch this to sld_warn on systems that support
+ * split lock/bus lock detect, unless there is a command line override.
+ */
+static enum split_lock_detect_state sld_state __ro_after_init = sld_off;
+static u64 msr_test_ctrl_cache __ro_after_init;
+
+/*
+ * With a name like MSR_TEST_CTL it should go without saying, but don't touch
+ * MSR_TEST_CTL unless the CPU is one of the whitelisted models.  Writing it
+ * on CPUs that do not support SLD can cause fireworks, even when writing '0'.
+ */
+static bool cpu_model_supports_sld __ro_after_init;
+
+/*
+ * Processors which have self-snooping capability can handle conflicting
+ * memory type across CPUs by snooping its own cache. However, there exists
+ * CPU models in which having conflicting memory types still leads to
+ * unpredictable behavior, machine check errors, or hangs. Clear this
+ * feature to prevent its use on machines with known erratas.
+ */
+static void check_memory_type_self_snoop_errata(struct cpuinfo_x86 *c)
+{
+	switch (c->x86_model) {
+	case INTEL_FAM6_CORE_YONAH:
+	case INTEL_FAM6_CORE2_MEROM:
+	case INTEL_FAM6_CORE2_MEROM_L:
+	case INTEL_FAM6_CORE2_PENRYN:
+	case INTEL_FAM6_CORE2_DUNNINGTON:
+	case INTEL_FAM6_NEHALEM:
+	case INTEL_FAM6_NEHALEM_G:
+	case INTEL_FAM6_NEHALEM_EP:
+	case INTEL_FAM6_NEHALEM_EX:
+	case INTEL_FAM6_WESTMERE:
+	case INTEL_FAM6_WESTMERE_EP:
+	case INTEL_FAM6_SANDYBRIDGE:
+		setup_clear_cpu_cap(X86_FEATURE_SELFSNOOP);
+	}
+}
+
+static bool ring3mwait_disabled __read_mostly;
+
+static int __init ring3mwait_disable(char *__unused)
+{
+	ring3mwait_disabled = true;
+	return 1;
+}
+__setup("ring3mwait=disable", ring3mwait_disable);
+
+static void probe_xeon_phi_r3mwait(struct cpuinfo_x86 *c)
+{
+	/*
+	 * Ring 3 MONITOR/MWAIT feature cannot be detected without
+	 * cpu model and family comparison.
+	 */
+	if (c->x86 != 6)
+		return;
+	switch (c->x86_model) {
+	case INTEL_FAM6_XEON_PHI_KNL:
+	case INTEL_FAM6_XEON_PHI_KNM:
+		break;
+	default:
+		return;
+	}
+
+	if (ring3mwait_disabled)
+		return;
+
+	set_cpu_cap(c, X86_FEATURE_RING3MWAIT);
+	this_cpu_or(msr_misc_features_shadow,
+		    1UL << MSR_MISC_FEATURES_ENABLES_RING3MWAIT_BIT);
+
+	if (c == &boot_cpu_data)
+		ELF_HWCAP2 |= HWCAP2_RING3MWAIT;
+}
+
+/*
+ * Early microcode releases for the Spectre v2 mitigation were broken.
+ * Information taken from;
+ * - https://newsroom.intel.com/wp-content/uploads/sites/11/2018/03/microcode-update-guidance.pdf
+ * - https://kb.vmware.com/s/article/52345
+ * - Microcode revisions observed in the wild
+ * - Release note from 20180108 microcode release
+ */
+struct sku_microcode {
+	u8 model;
+	u8 stepping;
+	u32 microcode;
+};
+static const struct sku_microcode spectre_bad_microcodes[] = {
+	{ INTEL_FAM6_KABYLAKE,		0x0B,	0x80 },
+	{ INTEL_FAM6_KABYLAKE,		0x0A,	0x80 },
+	{ INTEL_FAM6_KABYLAKE,		0x09,	0x80 },
+	{ INTEL_FAM6_KABYLAKE_L,	0x0A,	0x80 },
+	{ INTEL_FAM6_KABYLAKE_L,	0x09,	0x80 },
+	{ INTEL_FAM6_SKYLAKE_X,		0x03,	0x0100013e },
+	{ INTEL_FAM6_SKYLAKE_X,		0x04,	0x0200003c },
+	{ INTEL_FAM6_BROADWELL,		0x04,	0x28 },
+	{ INTEL_FAM6_BROADWELL_G,	0x01,	0x1b },
+	{ INTEL_FAM6_BROADWELL_D,	0x02,	0x14 },
+	{ INTEL_FAM6_BROADWELL_D,	0x03,	0x07000011 },
+	{ INTEL_FAM6_BROADWELL_X,	0x01,	0x0b000025 },
+	{ INTEL_FAM6_HASWELL_L,		0x01,	0x21 },
+	{ INTEL_FAM6_HASWELL_G,		0x01,	0x18 },
+	{ INTEL_FAM6_HASWELL,		0x03,	0x23 },
+	{ INTEL_FAM6_HASWELL_X,		0x02,	0x3b },
+	{ INTEL_FAM6_HASWELL_X,		0x04,	0x10 },
+	{ INTEL_FAM6_IVYBRIDGE_X,	0x04,	0x42a },
+	/* Observed in the wild */
+	{ INTEL_FAM6_SANDYBRIDGE_X,	0x06,	0x61b },
+	{ INTEL_FAM6_SANDYBRIDGE_X,	0x07,	0x712 },
+};
+
+static bool bad_spectre_microcode(struct cpuinfo_x86 *c)
+{
+	int i;
+
+	/*
+	 * We know that the hypervisor lie to us on the microcode version so
+	 * we may as well hope that it is running the correct version.
+	 */
+	if (cpu_has(c, X86_FEATURE_HYPERVISOR))
+		return false;
+
+	if (c->x86 != 6)
+		return false;
+
+	for (i = 0; i < ARRAY_SIZE(spectre_bad_microcodes); i++) {
+		if (c->x86_model == spectre_bad_microcodes[i].model &&
+		    c->x86_stepping == spectre_bad_microcodes[i].stepping)
+			return (c->microcode <= spectre_bad_microcodes[i].microcode);
+	}
+	return false;
+}
+
+static void early_init_intel(struct cpuinfo_x86 *c)
+{
+	u64 misc_enable;
+
+	/* Unmask CPUID levels if masked: */
+	if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
+		if (msr_clear_bit(MSR_IA32_MISC_ENABLE,
+				  MSR_IA32_MISC_ENABLE_LIMIT_CPUID_BIT) > 0) {
+			c->cpuid_level = cpuid_eax(0);
+			get_cpu_cap(c);
+		}
+	}
+
+	if ((c->x86 == 0xf && c->x86_model >= 0x03) ||
+		(c->x86 == 0x6 && c->x86_model >= 0x0e))
+		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
+
+	if (c->x86 >= 6 && !cpu_has(c, X86_FEATURE_IA64))
+		c->microcode = intel_get_microcode_revision();
+
+	/* Now if any of them are set, check the blacklist and clear the lot */
+	if ((cpu_has(c, X86_FEATURE_SPEC_CTRL) ||
+	     cpu_has(c, X86_FEATURE_INTEL_STIBP) ||
+	     cpu_has(c, X86_FEATURE_IBRS) || cpu_has(c, X86_FEATURE_IBPB) ||
+	     cpu_has(c, X86_FEATURE_STIBP)) && bad_spectre_microcode(c)) {
+		pr_warn("Intel Spectre v2 broken microcode detected; disabling Speculation Control\n");
+		setup_clear_cpu_cap(X86_FEATURE_IBRS);
+		setup_clear_cpu_cap(X86_FEATURE_IBPB);
+		setup_clear_cpu_cap(X86_FEATURE_STIBP);
+		setup_clear_cpu_cap(X86_FEATURE_SPEC_CTRL);
+		setup_clear_cpu_cap(X86_FEATURE_MSR_SPEC_CTRL);
+		setup_clear_cpu_cap(X86_FEATURE_INTEL_STIBP);
+		setup_clear_cpu_cap(X86_FEATURE_SSBD);
+		setup_clear_cpu_cap(X86_FEATURE_SPEC_CTRL_SSBD);
+	}
+
+	/*
+	 * Atom erratum AAE44/AAF40/AAG38/AAH41:
+	 *
+	 * A race condition between speculative fetches and invalidating
+	 * a large page.  This is worked around in microcode, but we
+	 * need the microcode to have already been loaded... so if it is
+	 * not, recommend a BIOS update and disable large pages.
+	 */
+	if (c->x86 == 6 && c->x86_model == 0x1c && c->x86_stepping <= 2 &&
+	    c->microcode < 0x20e) {
+		pr_warn("Atom PSE erratum detected, BIOS microcode update recommended\n");
+		clear_cpu_cap(c, X86_FEATURE_PSE);
+	}
+
+#ifdef CONFIG_X86_64
+	set_cpu_cap(c, X86_FEATURE_SYSENTER32);
+#else
+	/* Netburst reports 64 bytes clflush size, but does IO in 128 bytes */
+	if (c->x86 == 15 && c->x86_cache_alignment == 64)
+		c->x86_cache_alignment = 128;
+#endif
+
+	/* CPUID workaround for 0F33/0F34 CPU */
+	if (c->x86 == 0xF && c->x86_model == 0x3
+	    && (c->x86_stepping == 0x3 || c->x86_stepping == 0x4))
+		c->x86_phys_bits = 36;
+
+	/*
+	 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
+	 * with P/T states and does not stop in deep C-states.
+	 *
+	 * It is also reliable across cores and sockets. (but not across
+	 * cabinets - we turn it off in that case explicitly.)
+	 */
+	if (c->x86_power & (1 << 8)) {
+		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
+		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
+	}
+
+	/* Penwell and Cloverview have the TSC which doesn't sleep on S3 */
+	if (c->x86 == 6) {
+		switch (c->x86_model) {
+		case INTEL_FAM6_ATOM_SALTWELL_MID:
+		case INTEL_FAM6_ATOM_SALTWELL_TABLET:
+		case INTEL_FAM6_ATOM_SILVERMONT_MID:
+		case INTEL_FAM6_ATOM_AIRMONT_NP:
+			set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC_S3);
+			break;
+		default:
+			break;
+		}
+	}
+
+	/*
+	 * There is a known erratum on Pentium III and Core Solo
+	 * and Core Duo CPUs.
+	 * " Page with PAT set to WC while associated MTRR is UC
+	 *   may consolidate to UC "
+	 * Because of this erratum, it is better to stick with
+	 * setting WC in MTRR rather than using PAT on these CPUs.
+	 *
+	 * Enable PAT WC only on P4, Core 2 or later CPUs.
+	 */
+	if (c->x86 == 6 && c->x86_model < 15)
+		clear_cpu_cap(c, X86_FEATURE_PAT);
+
+	/*
+	 * If fast string is not enabled in IA32_MISC_ENABLE for any reason,
+	 * clear the fast string and enhanced fast string CPU capabilities.
+	 */
+	if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
+		rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
+		if (!(misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING)) {
+			pr_info("Disabled fast string operations\n");
+			setup_clear_cpu_cap(X86_FEATURE_REP_GOOD);
+			setup_clear_cpu_cap(X86_FEATURE_ERMS);
+		}
+	}
+
+	/*
+	 * Intel Quark Core DevMan_001.pdf section 6.4.11
+	 * "The operating system also is required to invalidate (i.e., flush)
+	 *  the TLB when any changes are made to any of the page table entries.
+	 *  The operating system must reload CR3 to cause the TLB to be flushed"
+	 *
+	 * As a result, boot_cpu_has(X86_FEATURE_PGE) in arch/x86/include/asm/tlbflush.h
+	 * should be false so that __flush_tlb_all() causes CR3 instead of CR4.PGE
+	 * to be modified.
+	 */
+	if (c->x86 == 5 && c->x86_model == 9) {
+		pr_info("Disabling PGE capability bit\n");
+		setup_clear_cpu_cap(X86_FEATURE_PGE);
+	}
+
+	if (c->cpuid_level >= 0x00000001) {
+		u32 eax, ebx, ecx, edx;
+
+		cpuid(0x00000001, &eax, &ebx, &ecx, &edx);
+		/*
+		 * If HTT (EDX[28]) is set EBX[16:23] contain the number of
+		 * apicids which are reserved per package. Store the resulting
+		 * shift value for the package management code.
+		 */
+		if (edx & (1U << 28))
+			c->x86_coreid_bits = get_count_order((ebx >> 16) & 0xff);
+	}
+
+	check_memory_type_self_snoop_errata(c);
+
+	/*
+	 * Get the number of SMT siblings early from the extended topology
+	 * leaf, if available. Otherwise try the legacy SMT detection.
+	 */
+	if (detect_extended_topology_early(c) < 0)
+		detect_ht_early(c);
+}
+
+static void bsp_init_intel(struct cpuinfo_x86 *c)
+{
+	resctrl_cpu_detect(c);
+}
+
+#ifdef CONFIG_X86_32
+/*
+ *	Early probe support logic for ppro memory erratum #50
+ *
+ *	This is called before we do cpu ident work
+ */
+
+int ppro_with_ram_bug(void)
+{
+	/* Uses data from early_cpu_detect now */
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
+	    boot_cpu_data.x86 == 6 &&
+	    boot_cpu_data.x86_model == 1 &&
+	    boot_cpu_data.x86_stepping < 8) {
+		pr_info("Pentium Pro with Errata#50 detected. Taking evasive action.\n");
+		return 1;
+	}
+	return 0;
+}
+
+static void intel_smp_check(struct cpuinfo_x86 *c)
+{
+	/* calling is from identify_secondary_cpu() ? */
+	if (!c->cpu_index)
+		return;
+
+	/*
+	 * Mask B, Pentium, but not Pentium MMX
+	 */
+	if (c->x86 == 5 &&
+	    c->x86_stepping >= 1 && c->x86_stepping <= 4 &&
+	    c->x86_model <= 3) {
+		/*
+		 * Remember we have B step Pentia with bugs
+		 */
+		WARN_ONCE(1, "WARNING: SMP operation may be unreliable"
+				    "with B stepping processors.\n");
+	}
+}
+
+static int forcepae;
+static int __init forcepae_setup(char *__unused)
+{
+	forcepae = 1;
+	return 1;
+}
+__setup("forcepae", forcepae_setup);
+
+static void intel_workarounds(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_X86_F00F_BUG
+	/*
+	 * All models of Pentium and Pentium with MMX technology CPUs
+	 * have the F0 0F bug, which lets nonprivileged users lock up the
+	 * system. Announce that the fault handler will be checking for it.
+	 * The Quark is also family 5, but does not have the same bug.
+	 */
+	clear_cpu_bug(c, X86_BUG_F00F);
+	if (c->x86 == 5 && c->x86_model < 9) {
+		static int f00f_workaround_enabled;
+
+		set_cpu_bug(c, X86_BUG_F00F);
+		if (!f00f_workaround_enabled) {
+			pr_notice("Intel Pentium with F0 0F bug - workaround enabled.\n");
+			f00f_workaround_enabled = 1;
+		}
+	}
+#endif
+
+	/*
+	 * SEP CPUID bug: Pentium Pro reports SEP but doesn't have it until
+	 * model 3 mask 3
+	 */
+	if ((c->x86<<8 | c->x86_model<<4 | c->x86_stepping) < 0x633)
+		clear_cpu_cap(c, X86_FEATURE_SEP);
+
+	/*
+	 * PAE CPUID issue: many Pentium M report no PAE but may have a
+	 * functionally usable PAE implementation.
+	 * Forcefully enable PAE if kernel parameter "forcepae" is present.
+	 */
+	if (forcepae) {
+		pr_warn("PAE forced!\n");
+		set_cpu_cap(c, X86_FEATURE_PAE);
+		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
+	}
+
+	/*
+	 * P4 Xeon erratum 037 workaround.
+	 * Hardware prefetcher may cause stale data to be loaded into the cache.
+	 */
+	if ((c->x86 == 15) && (c->x86_model == 1) && (c->x86_stepping == 1)) {
+		if (msr_set_bit(MSR_IA32_MISC_ENABLE,
+				MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE_BIT) > 0) {
+			pr_info("CPU: C0 stepping P4 Xeon detected.\n");
+			pr_info("CPU: Disabling hardware prefetching (Erratum 037)\n");
+		}
+	}
+
+	/*
+	 * See if we have a good local APIC by checking for buggy Pentia,
+	 * i.e. all B steppings and the C2 stepping of P54C when using their
+	 * integrated APIC (see 11AP erratum in "Pentium Processor
+	 * Specification Update").
+	 */
+	if (boot_cpu_has(X86_FEATURE_APIC) && (c->x86<<8 | c->x86_model<<4) == 0x520 &&
+	    (c->x86_stepping < 0x6 || c->x86_stepping == 0xb))
+		set_cpu_bug(c, X86_BUG_11AP);
+
+
+#ifdef CONFIG_X86_INTEL_USERCOPY
+	/*
+	 * Set up the preferred alignment for movsl bulk memory moves
+	 */
+	switch (c->x86) {
+	case 4:		/* 486: untested */
+		break;
+	case 5:		/* Old Pentia: untested */
+		break;
+	case 6:		/* PII/PIII only like movsl with 8-byte alignment */
+		movsl_mask.mask = 7;
+		break;
+	case 15:	/* P4 is OK down to 8-byte alignment */
+		movsl_mask.mask = 7;
+		break;
+	}
+#endif
+
+	intel_smp_check(c);
+}
+#else
+static void intel_workarounds(struct cpuinfo_x86 *c)
+{
+}
+#endif
+
+static void srat_detect_node(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_NUMA
+	unsigned node;
+	int cpu = smp_processor_id();
+
+	/* Don't do the funky fallback heuristics the AMD version employs
+	   for now. */
+	node = numa_cpu_node(cpu);
+	if (node == NUMA_NO_NODE || !node_online(node)) {
+		/* reuse the value from init_cpu_to_node() */
+		node = cpu_to_node(cpu);
+	}
+	numa_set_node(cpu, node);
+#endif
+}
+
+#define MSR_IA32_TME_ACTIVATE		0x982
+
+/* Helpers to access TME_ACTIVATE MSR */
+#define TME_ACTIVATE_LOCKED(x)		(x & 0x1)
+#define TME_ACTIVATE_ENABLED(x)		(x & 0x2)
+
+#define TME_ACTIVATE_POLICY(x)		((x >> 4) & 0xf)	/* Bits 7:4 */
+#define TME_ACTIVATE_POLICY_AES_XTS_128	0
+
+#define TME_ACTIVATE_KEYID_BITS(x)	((x >> 32) & 0xf)	/* Bits 35:32 */
+
+#define TME_ACTIVATE_CRYPTO_ALGS(x)	((x >> 48) & 0xffff)	/* Bits 63:48 */
+#define TME_ACTIVATE_CRYPTO_AES_XTS_128	1
+
+/* Values for mktme_status (SW only construct) */
+#define MKTME_ENABLED			0
+#define MKTME_DISABLED			1
+#define MKTME_UNINITIALIZED		2
+static int mktme_status = MKTME_UNINITIALIZED;
+
+static void detect_tme(struct cpuinfo_x86 *c)
+{
+	u64 tme_activate, tme_policy, tme_crypto_algs;
+	int keyid_bits = 0, nr_keyids = 0;
+	static u64 tme_activate_cpu0 = 0;
+
+	rdmsrl(MSR_IA32_TME_ACTIVATE, tme_activate);
+
+	if (mktme_status != MKTME_UNINITIALIZED) {
+		if (tme_activate != tme_activate_cpu0) {
+			/* Broken BIOS? */
+			pr_err_once("x86/tme: configuration is inconsistent between CPUs\n");
+			pr_err_once("x86/tme: MKTME is not usable\n");
+			mktme_status = MKTME_DISABLED;
+
+			/* Proceed. We may need to exclude bits from x86_phys_bits. */
+		}
+	} else {
+		tme_activate_cpu0 = tme_activate;
+	}
+
+	if (!TME_ACTIVATE_LOCKED(tme_activate) || !TME_ACTIVATE_ENABLED(tme_activate)) {
+		pr_info_once("x86/tme: not enabled by BIOS\n");
+		mktme_status = MKTME_DISABLED;
+		return;
+	}
+
+	if (mktme_status != MKTME_UNINITIALIZED)
+		goto detect_keyid_bits;
+
+	pr_info("x86/tme: enabled by BIOS\n");
+
+	tme_policy = TME_ACTIVATE_POLICY(tme_activate);
+	if (tme_policy != TME_ACTIVATE_POLICY_AES_XTS_128)
+		pr_warn("x86/tme: Unknown policy is active: %#llx\n", tme_policy);
+
+	tme_crypto_algs = TME_ACTIVATE_CRYPTO_ALGS(tme_activate);
+	if (!(tme_crypto_algs & TME_ACTIVATE_CRYPTO_AES_XTS_128)) {
+		pr_err("x86/mktme: No known encryption algorithm is supported: %#llx\n",
+				tme_crypto_algs);
+		mktme_status = MKTME_DISABLED;
+	}
+detect_keyid_bits:
+	keyid_bits = TME_ACTIVATE_KEYID_BITS(tme_activate);
+	nr_keyids = (1UL << keyid_bits) - 1;
+	if (nr_keyids) {
+		pr_info_once("x86/mktme: enabled by BIOS\n");
+		pr_info_once("x86/mktme: %d KeyIDs available\n", nr_keyids);
+	} else {
+		pr_info_once("x86/mktme: disabled by BIOS\n");
+	}
+
+	if (mktme_status == MKTME_UNINITIALIZED) {
+		/* MKTME is usable */
+		mktme_status = MKTME_ENABLED;
+	}
+
+	/*
+	 * KeyID bits effectively lower the number of physical address
+	 * bits.  Update cpuinfo_x86::x86_phys_bits accordingly.
+	 */
+	c->x86_phys_bits -= keyid_bits;
+}
+
+static void init_cpuid_fault(struct cpuinfo_x86 *c)
+{
+	u64 msr;
+
+	if (!rdmsrl_safe(MSR_PLATFORM_INFO, &msr)) {
+		if (msr & MSR_PLATFORM_INFO_CPUID_FAULT)
+			set_cpu_cap(c, X86_FEATURE_CPUID_FAULT);
+	}
+}
+
+static void init_intel_misc_features(struct cpuinfo_x86 *c)
+{
+	u64 msr;
+
+	if (rdmsrl_safe(MSR_MISC_FEATURES_ENABLES, &msr))
+		return;
+
+	/* Clear all MISC features */
+	this_cpu_write(msr_misc_features_shadow, 0);
+
+	/* Check features and update capabilities and shadow control bits */
+	init_cpuid_fault(c);
+	probe_xeon_phi_r3mwait(c);
+
+	msr = this_cpu_read(msr_misc_features_shadow);
+	wrmsrl(MSR_MISC_FEATURES_ENABLES, msr);
+}
+
+static void split_lock_init(void);
+static void bus_lock_init(void);
+
+static void init_intel(struct cpuinfo_x86 *c)
+{
+	early_init_intel(c);
+
+	intel_workarounds(c);
+
+	/*
+	 * Detect the extended topology information if available. This
+	 * will reinitialise the initial_apicid which will be used
+	 * in init_intel_cacheinfo()
+	 */
+	detect_extended_topology(c);
+
+	if (!cpu_has(c, X86_FEATURE_XTOPOLOGY)) {
+		/*
+		 * let's use the legacy cpuid vector 0x1 and 0x4 for topology
+		 * detection.
+		 */
+		detect_num_cpu_cores(c);
+#ifdef CONFIG_X86_32
+		detect_ht(c);
+#endif
+	}
+
+	init_intel_cacheinfo(c);
+
+	if (c->cpuid_level > 9) {
+		unsigned eax = cpuid_eax(10);
+		/* Check for version and the number of counters */
+		if ((eax & 0xff) && (((eax>>8) & 0xff) > 1))
+			set_cpu_cap(c, X86_FEATURE_ARCH_PERFMON);
+	}
+
+	if (cpu_has(c, X86_FEATURE_XMM2))
+		set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
+
+	if (boot_cpu_has(X86_FEATURE_DS)) {
+		unsigned int l1, l2;
+
+		rdmsr(MSR_IA32_MISC_ENABLE, l1, l2);
+		if (!(l1 & MSR_IA32_MISC_ENABLE_BTS_UNAVAIL))
+			set_cpu_cap(c, X86_FEATURE_BTS);
+		if (!(l1 & MSR_IA32_MISC_ENABLE_PEBS_UNAVAIL))
+			set_cpu_cap(c, X86_FEATURE_PEBS);
+	}
+
+	if (c->x86 == 6 && boot_cpu_has(X86_FEATURE_CLFLUSH) &&
+	    (c->x86_model == 29 || c->x86_model == 46 || c->x86_model == 47))
+		set_cpu_bug(c, X86_BUG_CLFLUSH_MONITOR);
+
+	if (c->x86 == 6 && boot_cpu_has(X86_FEATURE_MWAIT) &&
+		((c->x86_model == INTEL_FAM6_ATOM_GOLDMONT)))
+		set_cpu_bug(c, X86_BUG_MONITOR);
+
+#ifdef CONFIG_X86_64
+	if (c->x86 == 15)
+		c->x86_cache_alignment = c->x86_clflush_size * 2;
+	if (c->x86 == 6)
+		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
+#else
+	/*
+	 * Names for the Pentium II/Celeron processors
+	 * detectable only by also checking the cache size.
+	 * Dixon is NOT a Celeron.
+	 */
+	if (c->x86 == 6) {
+		unsigned int l2 = c->x86_cache_size;
+		char *p = NULL;
+
+		switch (c->x86_model) {
+		case 5:
+			if (l2 == 0)
+				p = "Celeron (Covington)";
+			else if (l2 == 256)
+				p = "Mobile Pentium II (Dixon)";
+			break;
+
+		case 6:
+			if (l2 == 128)
+				p = "Celeron (Mendocino)";
+			else if (c->x86_stepping == 0 || c->x86_stepping == 5)
+				p = "Celeron-A";
+			break;
+
+		case 8:
+			if (l2 == 128)
+				p = "Celeron (Coppermine)";
+			break;
+		}
+
+		if (p)
+			strcpy(c->x86_model_id, p);
+	}
+
+	if (c->x86 == 15)
+		set_cpu_cap(c, X86_FEATURE_P4);
+	if (c->x86 == 6)
+		set_cpu_cap(c, X86_FEATURE_P3);
+#endif
+
+	/* Work around errata */
+	srat_detect_node(c);
+
+	init_ia32_feat_ctl(c);
+
+	if (cpu_has(c, X86_FEATURE_TME))
+		detect_tme(c);
+
+	init_intel_misc_features(c);
+
+	split_lock_init();
+	bus_lock_init();
+
+	intel_init_thermal(c);
+}
+
+#ifdef CONFIG_X86_32
+static unsigned int intel_size_cache(struct cpuinfo_x86 *c, unsigned int size)
+{
+	/*
+	 * Intel PIII Tualatin. This comes in two flavours.
+	 * One has 256kb of cache, the other 512. We have no way
+	 * to determine which, so we use a boottime override
+	 * for the 512kb model, and assume 256 otherwise.
+	 */
+	if ((c->x86 == 6) && (c->x86_model == 11) && (size == 0))
+		size = 256;
+
+	/*
+	 * Intel Quark SoC X1000 contains a 4-way set associative
+	 * 16K cache with a 16 byte cache line and 256 lines per tag
+	 */
+	if ((c->x86 == 5) && (c->x86_model == 9))
+		size = 16;
+	return size;
+}
+#endif
+
+#define TLB_INST_4K	0x01
+#define TLB_INST_4M	0x02
+#define TLB_INST_2M_4M	0x03
+
+#define TLB_INST_ALL	0x05
+#define TLB_INST_1G	0x06
+
+#define TLB_DATA_4K	0x11
+#define TLB_DATA_4M	0x12
+#define TLB_DATA_2M_4M	0x13
+#define TLB_DATA_4K_4M	0x14
+
+#define TLB_DATA_1G	0x16
+
+#define TLB_DATA0_4K	0x21
+#define TLB_DATA0_4M	0x22
+#define TLB_DATA0_2M_4M	0x23
+
+#define STLB_4K		0x41
+#define STLB_4K_2M	0x42
+
+static const struct _tlb_table intel_tlb_table[] = {
+	{ 0x01, TLB_INST_4K,		32,	" TLB_INST 4 KByte pages, 4-way set associative" },
+	{ 0x02, TLB_INST_4M,		2,	" TLB_INST 4 MByte pages, full associative" },
+	{ 0x03, TLB_DATA_4K,		64,	" TLB_DATA 4 KByte pages, 4-way set associative" },
+	{ 0x04, TLB_DATA_4M,		8,	" TLB_DATA 4 MByte pages, 4-way set associative" },
+	{ 0x05, TLB_DATA_4M,		32,	" TLB_DATA 4 MByte pages, 4-way set associative" },
+	{ 0x0b, TLB_INST_4M,		4,	" TLB_INST 4 MByte pages, 4-way set associative" },
+	{ 0x4f, TLB_INST_4K,		32,	" TLB_INST 4 KByte pages" },
+	{ 0x50, TLB_INST_ALL,		64,	" TLB_INST 4 KByte and 2-MByte or 4-MByte pages" },
+	{ 0x51, TLB_INST_ALL,		128,	" TLB_INST 4 KByte and 2-MByte or 4-MByte pages" },
+	{ 0x52, TLB_INST_ALL,		256,	" TLB_INST 4 KByte and 2-MByte or 4-MByte pages" },
+	{ 0x55, TLB_INST_2M_4M,		7,	" TLB_INST 2-MByte or 4-MByte pages, fully associative" },
+	{ 0x56, TLB_DATA0_4M,		16,	" TLB_DATA0 4 MByte pages, 4-way set associative" },
+	{ 0x57, TLB_DATA0_4K,		16,	" TLB_DATA0 4 KByte pages, 4-way associative" },
+	{ 0x59, TLB_DATA0_4K,		16,	" TLB_DATA0 4 KByte pages, fully associative" },
+	{ 0x5a, TLB_DATA0_2M_4M,	32,	" TLB_DATA0 2-MByte or 4 MByte pages, 4-way set associative" },
+	{ 0x5b, TLB_DATA_4K_4M,		64,	" TLB_DATA 4 KByte and 4 MByte pages" },
+	{ 0x5c, TLB_DATA_4K_4M,		128,	" TLB_DATA 4 KByte and 4 MByte pages" },
+	{ 0x5d, TLB_DATA_4K_4M,		256,	" TLB_DATA 4 KByte and 4 MByte pages" },
+	{ 0x61, TLB_INST_4K,		48,	" TLB_INST 4 KByte pages, full associative" },
+	{ 0x63, TLB_DATA_1G,		4,	" TLB_DATA 1 GByte pages, 4-way set associative" },
+	{ 0x6b, TLB_DATA_4K,		256,	" TLB_DATA 4 KByte pages, 8-way associative" },
+	{ 0x6c, TLB_DATA_2M_4M,		128,	" TLB_DATA 2 MByte or 4 MByte pages, 8-way associative" },
+	{ 0x6d, TLB_DATA_1G,		16,	" TLB_DATA 1 GByte pages, fully associative" },
+	{ 0x76, TLB_INST_2M_4M,		8,	" TLB_INST 2-MByte or 4-MByte pages, fully associative" },
+	{ 0xb0, TLB_INST_4K,		128,	" TLB_INST 4 KByte pages, 4-way set associative" },
+	{ 0xb1, TLB_INST_2M_4M,		4,	" TLB_INST 2M pages, 4-way, 8 entries or 4M pages, 4-way entries" },
+	{ 0xb2, TLB_INST_4K,		64,	" TLB_INST 4KByte pages, 4-way set associative" },
+	{ 0xb3, TLB_DATA_4K,		128,	" TLB_DATA 4 KByte pages, 4-way set associative" },
+	{ 0xb4, TLB_DATA_4K,		256,	" TLB_DATA 4 KByte pages, 4-way associative" },
+	{ 0xb5, TLB_INST_4K,		64,	" TLB_INST 4 KByte pages, 8-way set associative" },
+	{ 0xb6, TLB_INST_4K,		128,	" TLB_INST 4 KByte pages, 8-way set associative" },
+	{ 0xba, TLB_DATA_4K,		64,	" TLB_DATA 4 KByte pages, 4-way associative" },
+	{ 0xc0, TLB_DATA_4K_4M,		8,	" TLB_DATA 4 KByte and 4 MByte pages, 4-way associative" },
+	{ 0xc1, STLB_4K_2M,		1024,	" STLB 4 KByte and 2 MByte pages, 8-way associative" },
+	{ 0xc2, TLB_DATA_2M_4M,		16,	" TLB_DATA 2 MByte/4MByte pages, 4-way associative" },
+	{ 0xca, STLB_4K,		512,	" STLB 4 KByte pages, 4-way associative" },
+	{ 0x00, 0, 0 }
+};
+
+static void intel_tlb_lookup(const unsigned char desc)
+{
+	unsigned char k;
+	if (desc == 0)
+		return;
+
+	/* look up this descriptor in the table */
+	for (k = 0; intel_tlb_table[k].descriptor != desc &&
+	     intel_tlb_table[k].descriptor != 0; k++)
+		;
+
+	if (intel_tlb_table[k].tlb_type == 0)
+		return;
+
+	switch (intel_tlb_table[k].tlb_type) {
+	case STLB_4K:
+		if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries;
+		if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries;
+		break;
+	case STLB_4K_2M:
+		if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries;
+		if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries;
+		if (tlb_lli_2m[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lli_2m[ENTRIES] = intel_tlb_table[k].entries;
+		if (tlb_lld_2m[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lld_2m[ENTRIES] = intel_tlb_table[k].entries;
+		if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries;
+		if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries;
+		break;
+	case TLB_INST_ALL:
+		if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries;
+		if (tlb_lli_2m[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lli_2m[ENTRIES] = intel_tlb_table[k].entries;
+		if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries;
+		break;
+	case TLB_INST_4K:
+		if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries;
+		break;
+	case TLB_INST_4M:
+		if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries;
+		break;
+	case TLB_INST_2M_4M:
+		if (tlb_lli_2m[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lli_2m[ENTRIES] = intel_tlb_table[k].entries;
+		if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries;
+		break;
+	case TLB_DATA_4K:
+	case TLB_DATA0_4K:
+		if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries;
+		break;
+	case TLB_DATA_4M:
+	case TLB_DATA0_4M:
+		if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries;
+		break;
+	case TLB_DATA_2M_4M:
+	case TLB_DATA0_2M_4M:
+		if (tlb_lld_2m[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lld_2m[ENTRIES] = intel_tlb_table[k].entries;
+		if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries;
+		break;
+	case TLB_DATA_4K_4M:
+		if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries;
+		if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries;
+		break;
+	case TLB_DATA_1G:
+		if (tlb_lld_1g[ENTRIES] < intel_tlb_table[k].entries)
+			tlb_lld_1g[ENTRIES] = intel_tlb_table[k].entries;
+		break;
+	}
+}
+
+static void intel_detect_tlb(struct cpuinfo_x86 *c)
+{
+	int i, j, n;
+	unsigned int regs[4];
+	unsigned char *desc = (unsigned char *)regs;
+
+	if (c->cpuid_level < 2)
+		return;
+
+	/* Number of times to iterate */
+	n = cpuid_eax(2) & 0xFF;
+
+	for (i = 0 ; i < n ; i++) {
+		cpuid(2, &regs[0], &regs[1], &regs[2], &regs[3]);
+
+		/* If bit 31 is set, this is an unknown format */
+		for (j = 0 ; j < 3 ; j++)
+			if (regs[j] & (1 << 31))
+				regs[j] = 0;
+
+		/* Byte 0 is level count, not a descriptor */
+		for (j = 1 ; j < 16 ; j++)
+			intel_tlb_lookup(desc[j]);
+	}
+}
+
+static const struct cpu_dev intel_cpu_dev = {
+	.c_vendor	= "Intel",
+	.c_ident	= { "GenuineIntel" },
+#ifdef CONFIG_X86_32
+	.legacy_models = {
+		{ .family = 4, .model_names =
+		  {
+			  [0] = "486 DX-25/33",
+			  [1] = "486 DX-50",
+			  [2] = "486 SX",
+			  [3] = "486 DX/2",
+			  [4] = "486 SL",
+			  [5] = "486 SX/2",
+			  [7] = "486 DX/2-WB",
+			  [8] = "486 DX/4",
+			  [9] = "486 DX/4-WB"
+		  }
+		},
+		{ .family = 5, .model_names =
+		  {
+			  [0] = "Pentium 60/66 A-step",
+			  [1] = "Pentium 60/66",
+			  [2] = "Pentium 75 - 200",
+			  [3] = "OverDrive PODP5V83",
+			  [4] = "Pentium MMX",
+			  [7] = "Mobile Pentium 75 - 200",
+			  [8] = "Mobile Pentium MMX",
+			  [9] = "Quark SoC X1000",
+		  }
+		},
+		{ .family = 6, .model_names =
+		  {
+			  [0] = "Pentium Pro A-step",
+			  [1] = "Pentium Pro",
+			  [3] = "Pentium II (Klamath)",
+			  [4] = "Pentium II (Deschutes)",
+			  [5] = "Pentium II (Deschutes)",
+			  [6] = "Mobile Pentium II",
+			  [7] = "Pentium III (Katmai)",
+			  [8] = "Pentium III (Coppermine)",
+			  [10] = "Pentium III (Cascades)",
+			  [11] = "Pentium III (Tualatin)",
+		  }
+		},
+		{ .family = 15, .model_names =
+		  {
+			  [0] = "Pentium 4 (Unknown)",
+			  [1] = "Pentium 4 (Willamette)",
+			  [2] = "Pentium 4 (Northwood)",
+			  [4] = "Pentium 4 (Foster)",
+			  [5] = "Pentium 4 (Foster)",
+		  }
+		},
+	},
+	.legacy_cache_size = intel_size_cache,
+#endif
+	.c_detect_tlb	= intel_detect_tlb,
+	.c_early_init   = early_init_intel,
+	.c_bsp_init	= bsp_init_intel,
+	.c_init		= init_intel,
+	.c_x86_vendor	= X86_VENDOR_INTEL,
+};
+
+cpu_dev_register(intel_cpu_dev);
+
+#undef pr_fmt
+#define pr_fmt(fmt) "x86/split lock detection: " fmt
+
+static const struct {
+	const char			*option;
+	enum split_lock_detect_state	state;
+} sld_options[] __initconst = {
+	{ "off",	sld_off   },
+	{ "warn",	sld_warn  },
+	{ "fatal",	sld_fatal },
+	{ "ratelimit:", sld_ratelimit },
+};
+
+static struct ratelimit_state bld_ratelimit;
+
+static unsigned int sysctl_sld_mitigate = 1;
+static DEFINE_SEMAPHORE(buslock_sem, 1);
+
+#ifdef CONFIG_PROC_SYSCTL
+static struct ctl_table sld_sysctls[] = {
+	{
+		.procname       = "split_lock_mitigate",
+		.data           = &sysctl_sld_mitigate,
+		.maxlen         = sizeof(unsigned int),
+		.mode           = 0644,
+		.proc_handler	= proc_douintvec_minmax,
+		.extra1         = SYSCTL_ZERO,
+		.extra2         = SYSCTL_ONE,
+	},
+	{}
+};
+
+static int __init sld_mitigate_sysctl_init(void)
+{
+	register_sysctl_init("kernel", sld_sysctls);
+	return 0;
+}
+
+late_initcall(sld_mitigate_sysctl_init);
+#endif
+
+static inline bool match_option(const char *arg, int arglen, const char *opt)
+{
+	int len = strlen(opt), ratelimit;
+
+	if (strncmp(arg, opt, len))
+		return false;
+
+	/*
+	 * Min ratelimit is 1 bus lock/sec.
+	 * Max ratelimit is 1000 bus locks/sec.
+	 */
+	if (sscanf(arg, "ratelimit:%d", &ratelimit) == 1 &&
+	    ratelimit > 0 && ratelimit <= 1000) {
+		ratelimit_state_init(&bld_ratelimit, HZ, ratelimit);
+		ratelimit_set_flags(&bld_ratelimit, RATELIMIT_MSG_ON_RELEASE);
+		return true;
+	}
+
+	return len == arglen;
+}
+
+static bool split_lock_verify_msr(bool on)
+{
+	u64 ctrl, tmp;
+
+	if (rdmsrl_safe(MSR_TEST_CTRL, &ctrl))
+		return false;
+	if (on)
+		ctrl |= MSR_TEST_CTRL_SPLIT_LOCK_DETECT;
+	else
+		ctrl &= ~MSR_TEST_CTRL_SPLIT_LOCK_DETECT;
+	if (wrmsrl_safe(MSR_TEST_CTRL, ctrl))
+		return false;
+	rdmsrl(MSR_TEST_CTRL, tmp);
+	return ctrl == tmp;
+}
+
+static void __init sld_state_setup(void)
+{
+	enum split_lock_detect_state state = sld_warn;
+	char arg[20];
+	int i, ret;
+
+	if (!boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT) &&
+	    !boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT))
+		return;
+
+	ret = cmdline_find_option(boot_command_line, "split_lock_detect",
+				  arg, sizeof(arg));
+	if (ret >= 0) {
+		for (i = 0; i < ARRAY_SIZE(sld_options); i++) {
+			if (match_option(arg, ret, sld_options[i].option)) {
+				state = sld_options[i].state;
+				break;
+			}
+		}
+	}
+	sld_state = state;
+}
+
+static void __init __split_lock_setup(void)
+{
+	if (!split_lock_verify_msr(false)) {
+		pr_info("MSR access failed: Disabled\n");
+		return;
+	}
+
+	rdmsrl(MSR_TEST_CTRL, msr_test_ctrl_cache);
+
+	if (!split_lock_verify_msr(true)) {
+		pr_info("MSR access failed: Disabled\n");
+		return;
+	}
+
+	/* Restore the MSR to its cached value. */
+	wrmsrl(MSR_TEST_CTRL, msr_test_ctrl_cache);
+
+	setup_force_cpu_cap(X86_FEATURE_SPLIT_LOCK_DETECT);
+}
+
+/*
+ * MSR_TEST_CTRL is per core, but we treat it like a per CPU MSR. Locking
+ * is not implemented as one thread could undo the setting of the other
+ * thread immediately after dropping the lock anyway.
+ */
+static void sld_update_msr(bool on)
+{
+	u64 test_ctrl_val = msr_test_ctrl_cache;
+
+	if (on)
+		test_ctrl_val |= MSR_TEST_CTRL_SPLIT_LOCK_DETECT;
+
+	wrmsrl(MSR_TEST_CTRL, test_ctrl_val);
+}
+
+static void split_lock_init(void)
+{
+	/*
+	 * #DB for bus lock handles ratelimit and #AC for split lock is
+	 * disabled.
+	 */
+	if (sld_state == sld_ratelimit) {
+		split_lock_verify_msr(false);
+		return;
+	}
+
+	if (cpu_model_supports_sld)
+		split_lock_verify_msr(sld_state != sld_off);
+}
+
+static void __split_lock_reenable_unlock(struct work_struct *work)
+{
+	sld_update_msr(true);
+	up(&buslock_sem);
+}
+
+static DECLARE_DELAYED_WORK(sl_reenable_unlock, __split_lock_reenable_unlock);
+
+static void __split_lock_reenable(struct work_struct *work)
+{
+	sld_update_msr(true);
+}
+static DECLARE_DELAYED_WORK(sl_reenable, __split_lock_reenable);
+
+/*
+ * If a CPU goes offline with pending delayed work to re-enable split lock
+ * detection then the delayed work will be executed on some other CPU. That
+ * handles releasing the buslock_sem, but because it executes on a
+ * different CPU probably won't re-enable split lock detection. This is a
+ * problem on HT systems since the sibling CPU on the same core may then be
+ * left running with split lock detection disabled.
+ *
+ * Unconditionally re-enable detection here.
+ */
+static int splitlock_cpu_offline(unsigned int cpu)
+{
+	sld_update_msr(true);
+
+	return 0;
+}
+
+static void split_lock_warn(unsigned long ip)
+{
+	struct delayed_work *work;
+	int cpu;
+
+	if (!current->reported_split_lock)
+		pr_warn_ratelimited("#AC: %s/%d took a split_lock trap at address: 0x%lx\n",
+				    current->comm, current->pid, ip);
+	current->reported_split_lock = 1;
+
+	if (sysctl_sld_mitigate) {
+		/*
+		 * misery factor #1:
+		 * sleep 10ms before trying to execute split lock.
+		 */
+		if (msleep_interruptible(10) > 0)
+			return;
+		/*
+		 * Misery factor #2:
+		 * only allow one buslocked disabled core at a time.
+		 */
+		if (down_interruptible(&buslock_sem) == -EINTR)
+			return;
+		work = &sl_reenable_unlock;
+	} else {
+		work = &sl_reenable;
+	}
+
+	cpu = get_cpu();
+	schedule_delayed_work_on(cpu, work, 2);
+
+	/* Disable split lock detection on this CPU to make progress */
+	sld_update_msr(false);
+	put_cpu();
+}
+
+bool handle_guest_split_lock(unsigned long ip)
+{
+	if (sld_state == sld_warn) {
+		split_lock_warn(ip);
+		return true;
+	}
+
+	pr_warn_once("#AC: %s/%d %s split_lock trap at address: 0x%lx\n",
+		     current->comm, current->pid,
+		     sld_state == sld_fatal ? "fatal" : "bogus", ip);
+
+	current->thread.error_code = 0;
+	current->thread.trap_nr = X86_TRAP_AC;
+	force_sig_fault(SIGBUS, BUS_ADRALN, NULL);
+	return false;
+}
+EXPORT_SYMBOL_GPL(handle_guest_split_lock);
+
+static void bus_lock_init(void)
+{
+	u64 val;
+
+	if (!boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT))
+		return;
+
+	rdmsrl(MSR_IA32_DEBUGCTLMSR, val);
+
+	if ((boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT) &&
+	    (sld_state == sld_warn || sld_state == sld_fatal)) ||
+	    sld_state == sld_off) {
+		/*
+		 * Warn and fatal are handled by #AC for split lock if #AC for
+		 * split lock is supported.
+		 */
+		val &= ~DEBUGCTLMSR_BUS_LOCK_DETECT;
+	} else {
+		val |= DEBUGCTLMSR_BUS_LOCK_DETECT;
+	}
+
+	wrmsrl(MSR_IA32_DEBUGCTLMSR, val);
+}
+
+bool handle_user_split_lock(struct pt_regs *regs, long error_code)
+{
+	if ((regs->flags & X86_EFLAGS_AC) || sld_state == sld_fatal)
+		return false;
+	split_lock_warn(regs->ip);
+	return true;
+}
+
+void handle_bus_lock(struct pt_regs *regs)
+{
+	switch (sld_state) {
+	case sld_off:
+		break;
+	case sld_ratelimit:
+		/* Enforce no more than bld_ratelimit bus locks/sec. */
+		while (!__ratelimit(&bld_ratelimit))
+			msleep(20);
+		/* Warn on the bus lock. */
+		fallthrough;
+	case sld_warn:
+		pr_warn_ratelimited("#DB: %s/%d took a bus_lock trap at address: 0x%lx\n",
+				    current->comm, current->pid, regs->ip);
+		break;
+	case sld_fatal:
+		force_sig_fault(SIGBUS, BUS_ADRALN, NULL);
+		break;
+	}
+}
+
+/*
+ * CPU models that are known to have the per-core split-lock detection
+ * feature even though they do not enumerate IA32_CORE_CAPABILITIES.
+ */
+static const struct x86_cpu_id split_lock_cpu_ids[] __initconst = {
+	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_X,	0),
+	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_L,	0),
+	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_D,	0),
+	{}
+};
+
+static void __init split_lock_setup(struct cpuinfo_x86 *c)
+{
+	const struct x86_cpu_id *m;
+	u64 ia32_core_caps;
+
+	if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
+		return;
+
+	/* Check for CPUs that have support but do not enumerate it: */
+	m = x86_match_cpu(split_lock_cpu_ids);
+	if (m)
+		goto supported;
+
+	if (!cpu_has(c, X86_FEATURE_CORE_CAPABILITIES))
+		return;
+
+	/*
+	 * Not all bits in MSR_IA32_CORE_CAPS are architectural, but
+	 * MSR_IA32_CORE_CAPS_SPLIT_LOCK_DETECT is.  All CPUs that set
+	 * it have split lock detection.
+	 */
+	rdmsrl(MSR_IA32_CORE_CAPS, ia32_core_caps);
+	if (ia32_core_caps & MSR_IA32_CORE_CAPS_SPLIT_LOCK_DETECT)
+		goto supported;
+
+	/* CPU is not in the model list and does not have the MSR bit: */
+	return;
+
+supported:
+	cpu_model_supports_sld = true;
+	__split_lock_setup();
+}
+
+static void sld_state_show(void)
+{
+	if (!boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT) &&
+	    !boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT))
+		return;
+
+	switch (sld_state) {
+	case sld_off:
+		pr_info("disabled\n");
+		break;
+	case sld_warn:
+		if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) {
+			pr_info("#AC: crashing the kernel on kernel split_locks and warning on user-space split_locks\n");
+			if (cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
+					      "x86/splitlock", NULL, splitlock_cpu_offline) < 0)
+				pr_warn("No splitlock CPU offline handler\n");
+		} else if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) {
+			pr_info("#DB: warning on user-space bus_locks\n");
+		}
+		break;
+	case sld_fatal:
+		if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) {
+			pr_info("#AC: crashing the kernel on kernel split_locks and sending SIGBUS on user-space split_locks\n");
+		} else if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) {
+			pr_info("#DB: sending SIGBUS on user-space bus_locks%s\n",
+				boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT) ?
+				" from non-WB" : "");
+		}
+		break;
+	case sld_ratelimit:
+		if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT))
+			pr_info("#DB: setting system wide bus lock rate limit to %u/sec\n", bld_ratelimit.burst);
+		break;
+	}
+}
+
+void __init sld_setup(struct cpuinfo_x86 *c)
+{
+	split_lock_setup(c);
+	sld_state_setup();
+	sld_state_show();
+}
+
+#define X86_HYBRID_CPU_TYPE_ID_SHIFT	24
+
+/**
+ * get_this_hybrid_cpu_type() - Get the type of this hybrid CPU
+ *
+ * Returns the CPU type [31:24] (i.e., Atom or Core) of a CPU in
+ * a hybrid processor. If the processor is not hybrid, returns 0.
+ */
+u8 get_this_hybrid_cpu_type(void)
+{
+	if (!cpu_feature_enabled(X86_FEATURE_HYBRID_CPU))
+		return 0;
+
+	return cpuid_eax(0x0000001a) >> X86_HYBRID_CPU_TYPE_ID_SHIFT;
+}
diff --git a/arch/x86/kernel/cpu/intel_epb.c b/arch/x86/kernel/cpu/intel_epb.c
new file mode 100644
index 0000000000..e4c3ba9132
--- /dev/null
+++ b/arch/x86/kernel/cpu/intel_epb.c
@@ -0,0 +1,240 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel Performance and Energy Bias Hint support.
+ *
+ * Copyright (C) 2019 Intel Corporation
+ *
+ * Author:
+ *	Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ */
+
+#include <linux/cpuhotplug.h>
+#include <linux/cpu.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/syscore_ops.h>
+#include <linux/pm.h>
+
+#include <asm/cpu_device_id.h>
+#include <asm/cpufeature.h>
+#include <asm/msr.h>
+
+/**
+ * DOC: overview
+ *
+ * The Performance and Energy Bias Hint (EPB) allows software to specify its
+ * preference with respect to the power-performance tradeoffs present in the
+ * processor.  Generally, the EPB is expected to be set by user space (directly
+ * via sysfs or with the help of the x86_energy_perf_policy tool), but there are
+ * two reasons for the kernel to update it.
+ *
+ * First, there are systems where the platform firmware resets the EPB during
+ * system-wide transitions from sleep states back into the working state
+ * effectively causing the previous EPB updates by user space to be lost.
+ * Thus the kernel needs to save the current EPB values for all CPUs during
+ * system-wide transitions to sleep states and restore them on the way back to
+ * the working state.  That can be achieved by saving EPB for secondary CPUs
+ * when they are taken offline during transitions into system sleep states and
+ * for the boot CPU in a syscore suspend operation, so that it can be restored
+ * for the boot CPU in a syscore resume operation and for the other CPUs when
+ * they are brought back online.  However, CPUs that are already offline when
+ * a system-wide PM transition is started are not taken offline again, but their
+ * EPB values may still be reset by the platform firmware during the transition,
+ * so in fact it is necessary to save the EPB of any CPU taken offline and to
+ * restore it when the given CPU goes back online at all times.
+ *
+ * Second, on many systems the initial EPB value coming from the platform
+ * firmware is 0 ('performance') and at least on some of them that is because
+ * the platform firmware does not initialize EPB at all with the assumption that
+ * the OS will do that anyway.  That sometimes is problematic, as it may cause
+ * the system battery to drain too fast, for example, so it is better to adjust
+ * it on CPU bring-up and if the initial EPB value for a given CPU is 0, the
+ * kernel changes it to 6 ('normal').
+ */
+
+static DEFINE_PER_CPU(u8, saved_epb);
+
+#define EPB_MASK	0x0fULL
+#define EPB_SAVED	0x10ULL
+#define MAX_EPB		EPB_MASK
+
+enum energy_perf_value_index {
+	EPB_INDEX_PERFORMANCE,
+	EPB_INDEX_BALANCE_PERFORMANCE,
+	EPB_INDEX_NORMAL,
+	EPB_INDEX_BALANCE_POWERSAVE,
+	EPB_INDEX_POWERSAVE,
+};
+
+static u8 energ_perf_values[] = {
+	[EPB_INDEX_PERFORMANCE] = ENERGY_PERF_BIAS_PERFORMANCE,
+	[EPB_INDEX_BALANCE_PERFORMANCE] = ENERGY_PERF_BIAS_BALANCE_PERFORMANCE,
+	[EPB_INDEX_NORMAL] = ENERGY_PERF_BIAS_NORMAL,
+	[EPB_INDEX_BALANCE_POWERSAVE] = ENERGY_PERF_BIAS_BALANCE_POWERSAVE,
+	[EPB_INDEX_POWERSAVE] = ENERGY_PERF_BIAS_POWERSAVE,
+};
+
+static int intel_epb_save(void)
+{
+	u64 epb;
+
+	rdmsrl(MSR_IA32_ENERGY_PERF_BIAS, epb);
+	/*
+	 * Ensure that saved_epb will always be nonzero after this write even if
+	 * the EPB value read from the MSR is 0.
+	 */
+	this_cpu_write(saved_epb, (epb & EPB_MASK) | EPB_SAVED);
+
+	return 0;
+}
+
+static void intel_epb_restore(void)
+{
+	u64 val = this_cpu_read(saved_epb);
+	u64 epb;
+
+	rdmsrl(MSR_IA32_ENERGY_PERF_BIAS, epb);
+	if (val) {
+		val &= EPB_MASK;
+	} else {
+		/*
+		 * Because intel_epb_save() has not run for the current CPU yet,
+		 * it is going online for the first time, so if its EPB value is
+		 * 0 ('performance') at this point, assume that it has not been
+		 * initialized by the platform firmware and set it to 6
+		 * ('normal').
+		 */
+		val = epb & EPB_MASK;
+		if (val == ENERGY_PERF_BIAS_PERFORMANCE) {
+			val = energ_perf_values[EPB_INDEX_NORMAL];
+			pr_warn_once("ENERGY_PERF_BIAS: Set to 'normal', was 'performance'\n");
+		}
+	}
+	wrmsrl(MSR_IA32_ENERGY_PERF_BIAS, (epb & ~EPB_MASK) | val);
+}
+
+static struct syscore_ops intel_epb_syscore_ops = {
+	.suspend = intel_epb_save,
+	.resume = intel_epb_restore,
+};
+
+static const char * const energy_perf_strings[] = {
+	[EPB_INDEX_PERFORMANCE] = "performance",
+	[EPB_INDEX_BALANCE_PERFORMANCE] = "balance-performance",
+	[EPB_INDEX_NORMAL] = "normal",
+	[EPB_INDEX_BALANCE_POWERSAVE] = "balance-power",
+	[EPB_INDEX_POWERSAVE] = "power",
+};
+
+static ssize_t energy_perf_bias_show(struct device *dev,
+				     struct device_attribute *attr,
+				     char *buf)
+{
+	unsigned int cpu = dev->id;
+	u64 epb;
+	int ret;
+
+	ret = rdmsrl_on_cpu(cpu, MSR_IA32_ENERGY_PERF_BIAS, &epb);
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%llu\n", epb);
+}
+
+static ssize_t energy_perf_bias_store(struct device *dev,
+				      struct device_attribute *attr,
+				      const char *buf, size_t count)
+{
+	unsigned int cpu = dev->id;
+	u64 epb, val;
+	int ret;
+
+	ret = __sysfs_match_string(energy_perf_strings,
+				   ARRAY_SIZE(energy_perf_strings), buf);
+	if (ret >= 0)
+		val = energ_perf_values[ret];
+	else if (kstrtou64(buf, 0, &val) || val > MAX_EPB)
+		return -EINVAL;
+
+	ret = rdmsrl_on_cpu(cpu, MSR_IA32_ENERGY_PERF_BIAS, &epb);
+	if (ret < 0)
+		return ret;
+
+	ret = wrmsrl_on_cpu(cpu, MSR_IA32_ENERGY_PERF_BIAS,
+			    (epb & ~EPB_MASK) | val);
+	if (ret < 0)
+		return ret;
+
+	return count;
+}
+
+static DEVICE_ATTR_RW(energy_perf_bias);
+
+static struct attribute *intel_epb_attrs[] = {
+	&dev_attr_energy_perf_bias.attr,
+	NULL
+};
+
+static const struct attribute_group intel_epb_attr_group = {
+	.name = power_group_name,
+	.attrs =  intel_epb_attrs
+};
+
+static int intel_epb_online(unsigned int cpu)
+{
+	struct device *cpu_dev = get_cpu_device(cpu);
+
+	intel_epb_restore();
+	if (!cpuhp_tasks_frozen)
+		sysfs_merge_group(&cpu_dev->kobj, &intel_epb_attr_group);
+
+	return 0;
+}
+
+static int intel_epb_offline(unsigned int cpu)
+{
+	struct device *cpu_dev = get_cpu_device(cpu);
+
+	if (!cpuhp_tasks_frozen)
+		sysfs_unmerge_group(&cpu_dev->kobj, &intel_epb_attr_group);
+
+	intel_epb_save();
+	return 0;
+}
+
+static const struct x86_cpu_id intel_epb_normal[] = {
+	X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE_L,
+				   ENERGY_PERF_BIAS_NORMAL_POWERSAVE),
+	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GRACEMONT,
+				   ENERGY_PERF_BIAS_NORMAL_POWERSAVE),
+	X86_MATCH_INTEL_FAM6_MODEL(RAPTORLAKE_P,
+				   ENERGY_PERF_BIAS_NORMAL_POWERSAVE),
+	{}
+};
+
+static __init int intel_epb_init(void)
+{
+	const struct x86_cpu_id *id = x86_match_cpu(intel_epb_normal);
+	int ret;
+
+	if (!boot_cpu_has(X86_FEATURE_EPB))
+		return -ENODEV;
+
+	if (id)
+		energ_perf_values[EPB_INDEX_NORMAL] = id->driver_data;
+
+	ret = cpuhp_setup_state(CPUHP_AP_X86_INTEL_EPB_ONLINE,
+				"x86/intel/epb:online", intel_epb_online,
+				intel_epb_offline);
+	if (ret < 0)
+		goto err_out_online;
+
+	register_syscore_ops(&intel_epb_syscore_ops);
+	return 0;
+
+err_out_online:
+	cpuhp_remove_state(CPUHP_AP_X86_INTEL_EPB_ONLINE);
+	return ret;
+}
+subsys_initcall(intel_epb_init);
diff --git a/arch/x86/kernel/cpu/intel_pconfig.c b/arch/x86/kernel/cpu/intel_pconfig.c
new file mode 100644
index 0000000000..0771a905b2
--- /dev/null
+++ b/arch/x86/kernel/cpu/intel_pconfig.c
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel PCONFIG instruction support.
+ *
+ * Copyright (C) 2017 Intel Corporation
+ *
+ * Author:
+ *	Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
+ */
+
+#include <asm/cpufeature.h>
+#include <asm/intel_pconfig.h>
+
+#define	PCONFIG_CPUID			0x1b
+
+#define PCONFIG_CPUID_SUBLEAF_MASK	((1 << 12) - 1)
+
+/* Subleaf type (EAX) for PCONFIG CPUID leaf (0x1B) */
+enum {
+	PCONFIG_CPUID_SUBLEAF_INVALID	= 0,
+	PCONFIG_CPUID_SUBLEAF_TARGETID	= 1,
+};
+
+/* Bitmask of supported targets */
+static u64 targets_supported __read_mostly;
+
+int pconfig_target_supported(enum pconfig_target target)
+{
+	/*
+	 * We would need to re-think the implementation once we get > 64
+	 * PCONFIG targets. Spec allows up to 2^32 targets.
+	 */
+	BUILD_BUG_ON(PCONFIG_TARGET_NR >= 64);
+
+	if (WARN_ON_ONCE(target >= 64))
+		return 0;
+	return targets_supported & (1ULL << target);
+}
+
+static int __init intel_pconfig_init(void)
+{
+	int subleaf;
+
+	if (!boot_cpu_has(X86_FEATURE_PCONFIG))
+		return 0;
+
+	/*
+	 * Scan subleafs of PCONFIG CPUID leaf.
+	 *
+	 * Subleafs of the same type need not to be consecutive.
+	 *
+	 * Stop on the first invalid subleaf type. All subleafs after the first
+	 * invalid are invalid too.
+	 */
+	for (subleaf = 0; subleaf < INT_MAX; subleaf++) {
+		struct cpuid_regs regs;
+
+		cpuid_count(PCONFIG_CPUID, subleaf,
+				&regs.eax, &regs.ebx, &regs.ecx, &regs.edx);
+
+		switch (regs.eax & PCONFIG_CPUID_SUBLEAF_MASK) {
+		case PCONFIG_CPUID_SUBLEAF_INVALID:
+			/* Stop on the first invalid subleaf */
+			goto out;
+		case PCONFIG_CPUID_SUBLEAF_TARGETID:
+			/* Mark supported PCONFIG targets */
+			if (regs.ebx < 64)
+				targets_supported |= (1ULL << regs.ebx);
+			if (regs.ecx < 64)
+				targets_supported |= (1ULL << regs.ecx);
+			if (regs.edx < 64)
+				targets_supported |= (1ULL << regs.edx);
+			break;
+		default:
+			/* Unknown CPUID.PCONFIG subleaf: ignore */
+			break;
+		}
+	}
+out:
+	return 0;
+}
+arch_initcall(intel_pconfig_init);
diff --git a/arch/x86/kernel/cpu/match.c b/arch/x86/kernel/cpu/match.c
new file mode 100644
index 0000000000..ad6776081e
--- /dev/null
+++ b/arch/x86/kernel/cpu/match.c
@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <asm/cpu_device_id.h>
+#include <asm/cpufeature.h>
+#include <linux/cpu.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+
+/**
+ * x86_match_cpu - match current CPU again an array of x86_cpu_ids
+ * @match: Pointer to array of x86_cpu_ids. Last entry terminated with
+ *         {}.
+ *
+ * Return the entry if the current CPU matches the entries in the
+ * passed x86_cpu_id match table. Otherwise NULL.  The match table
+ * contains vendor (X86_VENDOR_*), family, model and feature bits or
+ * respective wildcard entries.
+ *
+ * A typical table entry would be to match a specific CPU
+ *
+ * X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6, INTEL_FAM6_BROADWELL,
+ *				      X86_FEATURE_ANY, NULL);
+ *
+ * Fields can be wildcarded with %X86_VENDOR_ANY, %X86_FAMILY_ANY,
+ * %X86_MODEL_ANY, %X86_FEATURE_ANY (except for vendor)
+ *
+ * asm/cpu_device_id.h contains a set of useful macros which are shortcuts
+ * for various common selections. The above can be shortened to:
+ *
+ * X86_MATCH_INTEL_FAM6_MODEL(BROADWELL, NULL);
+ *
+ * Arrays used to match for this should also be declared using
+ * MODULE_DEVICE_TABLE(x86cpu, ...)
+ *
+ * This always matches against the boot cpu, assuming models and features are
+ * consistent over all CPUs.
+ */
+const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match)
+{
+	const struct x86_cpu_id *m;
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+
+	for (m = match;
+	     m->vendor | m->family | m->model | m->steppings | m->feature;
+	     m++) {
+		if (m->vendor != X86_VENDOR_ANY && c->x86_vendor != m->vendor)
+			continue;
+		if (m->family != X86_FAMILY_ANY && c->x86 != m->family)
+			continue;
+		if (m->model != X86_MODEL_ANY && c->x86_model != m->model)
+			continue;
+		if (m->steppings != X86_STEPPING_ANY &&
+		    !(BIT(c->x86_stepping) & m->steppings))
+			continue;
+		if (m->feature != X86_FEATURE_ANY && !cpu_has(c, m->feature))
+			continue;
+		return m;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(x86_match_cpu);
+
+static const struct x86_cpu_desc *
+x86_match_cpu_with_stepping(const struct x86_cpu_desc *match)
+{
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+	const struct x86_cpu_desc *m;
+
+	for (m = match; m->x86_family | m->x86_model; m++) {
+		if (c->x86_vendor != m->x86_vendor)
+			continue;
+		if (c->x86 != m->x86_family)
+			continue;
+		if (c->x86_model != m->x86_model)
+			continue;
+		if (c->x86_stepping != m->x86_stepping)
+			continue;
+		return m;
+	}
+	return NULL;
+}
+
+bool x86_cpu_has_min_microcode_rev(const struct x86_cpu_desc *table)
+{
+	const struct x86_cpu_desc *res = x86_match_cpu_with_stepping(table);
+
+	if (!res || res->x86_microcode_rev > boot_cpu_data.microcode)
+		return false;
+
+	return true;
+}
+EXPORT_SYMBOL_GPL(x86_cpu_has_min_microcode_rev);
diff --git a/arch/x86/kernel/cpu/mce/Makefile b/arch/x86/kernel/cpu/mce/Makefile
new file mode 100644
index 0000000000..015856abdb
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/Makefile
@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-y				=  core.o severity.o genpool.o
+
+obj-$(CONFIG_X86_ANCIENT_MCE)	+= winchip.o p5.o
+obj-$(CONFIG_X86_MCE_INTEL)	+= intel.o
+obj-$(CONFIG_X86_MCE_AMD)	+= amd.o
+obj-$(CONFIG_X86_MCE_THRESHOLD) += threshold.o
+
+mce-inject-y			:= inject.o
+obj-$(CONFIG_X86_MCE_INJECT)	+= mce-inject.o
+
+obj-$(CONFIG_ACPI_APEI)		+= apei.o
+
+obj-$(CONFIG_X86_MCELOG_LEGACY)	+= dev-mcelog.o
diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c
new file mode 100644
index 0000000000..c267f43de3
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/amd.c
@@ -0,0 +1,1374 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  (c) 2005-2016 Advanced Micro Devices, Inc.
+ *
+ *  Written by Jacob Shin - AMD, Inc.
+ *  Maintained by: Borislav Petkov <bp@alien8.de>
+ *
+ *  All MC4_MISCi registers are shared between cores on a node.
+ */
+#include <linux/interrupt.h>
+#include <linux/notifier.h>
+#include <linux/kobject.h>
+#include <linux/percpu.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/sysfs.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/cpu.h>
+#include <linux/smp.h>
+#include <linux/string.h>
+
+#include <asm/amd_nb.h>
+#include <asm/traps.h>
+#include <asm/apic.h>
+#include <asm/mce.h>
+#include <asm/msr.h>
+#include <asm/trace/irq_vectors.h>
+
+#include "internal.h"
+
+#define NR_BLOCKS         5
+#define THRESHOLD_MAX     0xFFF
+#define INT_TYPE_APIC     0x00020000
+#define MASK_VALID_HI     0x80000000
+#define MASK_CNTP_HI      0x40000000
+#define MASK_LOCKED_HI    0x20000000
+#define MASK_LVTOFF_HI    0x00F00000
+#define MASK_COUNT_EN_HI  0x00080000
+#define MASK_INT_TYPE_HI  0x00060000
+#define MASK_OVERFLOW_HI  0x00010000
+#define MASK_ERR_COUNT_HI 0x00000FFF
+#define MASK_BLKPTR_LO    0xFF000000
+#define MCG_XBLK_ADDR     0xC0000400
+
+/* Deferred error settings */
+#define MSR_CU_DEF_ERR		0xC0000410
+#define MASK_DEF_LVTOFF		0x000000F0
+#define MASK_DEF_INT_TYPE	0x00000006
+#define DEF_LVT_OFF		0x2
+#define DEF_INT_TYPE_APIC	0x2
+
+/* Scalable MCA: */
+
+/* Threshold LVT offset is at MSR0xC0000410[15:12] */
+#define SMCA_THR_LVT_OFF	0xF000
+
+static bool thresholding_irq_en;
+
+static const char * const th_names[] = {
+	"load_store",
+	"insn_fetch",
+	"combined_unit",
+	"decode_unit",
+	"northbridge",
+	"execution_unit",
+};
+
+static const char * const smca_umc_block_names[] = {
+	"dram_ecc",
+	"misc_umc"
+};
+
+#define HWID_MCATYPE(hwid, mcatype) (((hwid) << 16) | (mcatype))
+
+struct smca_hwid {
+	unsigned int bank_type;	/* Use with smca_bank_types for easy indexing. */
+	u32 hwid_mcatype;	/* (hwid,mcatype) tuple */
+};
+
+struct smca_bank {
+	const struct smca_hwid *hwid;
+	u32 id;			/* Value of MCA_IPID[InstanceId]. */
+	u8 sysfs_id;		/* Value used for sysfs name. */
+};
+
+static DEFINE_PER_CPU_READ_MOSTLY(struct smca_bank[MAX_NR_BANKS], smca_banks);
+static DEFINE_PER_CPU_READ_MOSTLY(u8[N_SMCA_BANK_TYPES], smca_bank_counts);
+
+struct smca_bank_name {
+	const char *name;	/* Short name for sysfs */
+	const char *long_name;	/* Long name for pretty-printing */
+};
+
+static struct smca_bank_name smca_names[] = {
+	[SMCA_LS ... SMCA_LS_V2]	= { "load_store",	"Load Store Unit" },
+	[SMCA_IF]			= { "insn_fetch",	"Instruction Fetch Unit" },
+	[SMCA_L2_CACHE]			= { "l2_cache",		"L2 Cache" },
+	[SMCA_DE]			= { "decode_unit",	"Decode Unit" },
+	[SMCA_RESERVED]			= { "reserved",		"Reserved" },
+	[SMCA_EX]			= { "execution_unit",	"Execution Unit" },
+	[SMCA_FP]			= { "floating_point",	"Floating Point Unit" },
+	[SMCA_L3_CACHE]			= { "l3_cache",		"L3 Cache" },
+	[SMCA_CS ... SMCA_CS_V2]	= { "coherent_slave",	"Coherent Slave" },
+	[SMCA_PIE]			= { "pie",		"Power, Interrupts, etc." },
+
+	/* UMC v2 is separate because both of them can exist in a single system. */
+	[SMCA_UMC]			= { "umc",		"Unified Memory Controller" },
+	[SMCA_UMC_V2]			= { "umc_v2",		"Unified Memory Controller v2" },
+	[SMCA_PB]			= { "param_block",	"Parameter Block" },
+	[SMCA_PSP ... SMCA_PSP_V2]	= { "psp",		"Platform Security Processor" },
+	[SMCA_SMU ... SMCA_SMU_V2]	= { "smu",		"System Management Unit" },
+	[SMCA_MP5]			= { "mp5",		"Microprocessor 5 Unit" },
+	[SMCA_MPDMA]			= { "mpdma",		"MPDMA Unit" },
+	[SMCA_NBIO]			= { "nbio",		"Northbridge IO Unit" },
+	[SMCA_PCIE ... SMCA_PCIE_V2]	= { "pcie",		"PCI Express Unit" },
+	[SMCA_XGMI_PCS]			= { "xgmi_pcs",		"Ext Global Memory Interconnect PCS Unit" },
+	[SMCA_NBIF]			= { "nbif",		"NBIF Unit" },
+	[SMCA_SHUB]			= { "shub",		"System Hub Unit" },
+	[SMCA_SATA]			= { "sata",		"SATA Unit" },
+	[SMCA_USB]			= { "usb",		"USB Unit" },
+	[SMCA_GMI_PCS]			= { "gmi_pcs",		"Global Memory Interconnect PCS Unit" },
+	[SMCA_XGMI_PHY]			= { "xgmi_phy",		"Ext Global Memory Interconnect PHY Unit" },
+	[SMCA_WAFL_PHY]			= { "wafl_phy",		"WAFL PHY Unit" },
+	[SMCA_GMI_PHY]			= { "gmi_phy",		"Global Memory Interconnect PHY Unit" },
+};
+
+static const char *smca_get_name(enum smca_bank_types t)
+{
+	if (t >= N_SMCA_BANK_TYPES)
+		return NULL;
+
+	return smca_names[t].name;
+}
+
+const char *smca_get_long_name(enum smca_bank_types t)
+{
+	if (t >= N_SMCA_BANK_TYPES)
+		return NULL;
+
+	return smca_names[t].long_name;
+}
+EXPORT_SYMBOL_GPL(smca_get_long_name);
+
+enum smca_bank_types smca_get_bank_type(unsigned int cpu, unsigned int bank)
+{
+	struct smca_bank *b;
+
+	if (bank >= MAX_NR_BANKS)
+		return N_SMCA_BANK_TYPES;
+
+	b = &per_cpu(smca_banks, cpu)[bank];
+	if (!b->hwid)
+		return N_SMCA_BANK_TYPES;
+
+	return b->hwid->bank_type;
+}
+EXPORT_SYMBOL_GPL(smca_get_bank_type);
+
+static const struct smca_hwid smca_hwid_mcatypes[] = {
+	/* { bank_type, hwid_mcatype } */
+
+	/* Reserved type */
+	{ SMCA_RESERVED, HWID_MCATYPE(0x00, 0x0)	},
+
+	/* ZN Core (HWID=0xB0) MCA types */
+	{ SMCA_LS,	 HWID_MCATYPE(0xB0, 0x0)	},
+	{ SMCA_LS_V2,	 HWID_MCATYPE(0xB0, 0x10)	},
+	{ SMCA_IF,	 HWID_MCATYPE(0xB0, 0x1)	},
+	{ SMCA_L2_CACHE, HWID_MCATYPE(0xB0, 0x2)	},
+	{ SMCA_DE,	 HWID_MCATYPE(0xB0, 0x3)	},
+	/* HWID 0xB0 MCATYPE 0x4 is Reserved */
+	{ SMCA_EX,	 HWID_MCATYPE(0xB0, 0x5)	},
+	{ SMCA_FP,	 HWID_MCATYPE(0xB0, 0x6)	},
+	{ SMCA_L3_CACHE, HWID_MCATYPE(0xB0, 0x7)	},
+
+	/* Data Fabric MCA types */
+	{ SMCA_CS,	 HWID_MCATYPE(0x2E, 0x0)	},
+	{ SMCA_PIE,	 HWID_MCATYPE(0x2E, 0x1)	},
+	{ SMCA_CS_V2,	 HWID_MCATYPE(0x2E, 0x2)	},
+
+	/* Unified Memory Controller MCA type */
+	{ SMCA_UMC,	 HWID_MCATYPE(0x96, 0x0)	},
+	{ SMCA_UMC_V2,	 HWID_MCATYPE(0x96, 0x1)	},
+
+	/* Parameter Block MCA type */
+	{ SMCA_PB,	 HWID_MCATYPE(0x05, 0x0)	},
+
+	/* Platform Security Processor MCA type */
+	{ SMCA_PSP,	 HWID_MCATYPE(0xFF, 0x0)	},
+	{ SMCA_PSP_V2,	 HWID_MCATYPE(0xFF, 0x1)	},
+
+	/* System Management Unit MCA type */
+	{ SMCA_SMU,	 HWID_MCATYPE(0x01, 0x0)	},
+	{ SMCA_SMU_V2,	 HWID_MCATYPE(0x01, 0x1)	},
+
+	/* Microprocessor 5 Unit MCA type */
+	{ SMCA_MP5,	 HWID_MCATYPE(0x01, 0x2)	},
+
+	/* MPDMA MCA type */
+	{ SMCA_MPDMA,	 HWID_MCATYPE(0x01, 0x3)	},
+
+	/* Northbridge IO Unit MCA type */
+	{ SMCA_NBIO,	 HWID_MCATYPE(0x18, 0x0)	},
+
+	/* PCI Express Unit MCA type */
+	{ SMCA_PCIE,	 HWID_MCATYPE(0x46, 0x0)	},
+	{ SMCA_PCIE_V2,	 HWID_MCATYPE(0x46, 0x1)	},
+
+	{ SMCA_XGMI_PCS, HWID_MCATYPE(0x50, 0x0)	},
+	{ SMCA_NBIF,	 HWID_MCATYPE(0x6C, 0x0)	},
+	{ SMCA_SHUB,	 HWID_MCATYPE(0x80, 0x0)	},
+	{ SMCA_SATA,	 HWID_MCATYPE(0xA8, 0x0)	},
+	{ SMCA_USB,	 HWID_MCATYPE(0xAA, 0x0)	},
+	{ SMCA_GMI_PCS,  HWID_MCATYPE(0x241, 0x0)	},
+	{ SMCA_XGMI_PHY, HWID_MCATYPE(0x259, 0x0)	},
+	{ SMCA_WAFL_PHY, HWID_MCATYPE(0x267, 0x0)	},
+	{ SMCA_GMI_PHY,	 HWID_MCATYPE(0x269, 0x0)	},
+};
+
+/*
+ * In SMCA enabled processors, we can have multiple banks for a given IP type.
+ * So to define a unique name for each bank, we use a temp c-string to append
+ * the MCA_IPID[InstanceId] to type's name in get_name().
+ *
+ * InstanceId is 32 bits which is 8 characters. Make sure MAX_MCATYPE_NAME_LEN
+ * is greater than 8 plus 1 (for underscore) plus length of longest type name.
+ */
+#define MAX_MCATYPE_NAME_LEN	30
+static char buf_mcatype[MAX_MCATYPE_NAME_LEN];
+
+static DEFINE_PER_CPU(struct threshold_bank **, threshold_banks);
+
+/*
+ * A list of the banks enabled on each logical CPU. Controls which respective
+ * descriptors to initialize later in mce_threshold_create_device().
+ */
+static DEFINE_PER_CPU(u64, bank_map);
+
+/* Map of banks that have more than MCA_MISC0 available. */
+static DEFINE_PER_CPU(u64, smca_misc_banks_map);
+
+static void amd_threshold_interrupt(void);
+static void amd_deferred_error_interrupt(void);
+
+static void default_deferred_error_interrupt(void)
+{
+	pr_err("Unexpected deferred interrupt at vector %x\n", DEFERRED_ERROR_VECTOR);
+}
+void (*deferred_error_int_vector)(void) = default_deferred_error_interrupt;
+
+static void smca_set_misc_banks_map(unsigned int bank, unsigned int cpu)
+{
+	u32 low, high;
+
+	/*
+	 * For SMCA enabled processors, BLKPTR field of the first MISC register
+	 * (MCx_MISC0) indicates presence of additional MISC regs set (MISC1-4).
+	 */
+	if (rdmsr_safe(MSR_AMD64_SMCA_MCx_CONFIG(bank), &low, &high))
+		return;
+
+	if (!(low & MCI_CONFIG_MCAX))
+		return;
+
+	if (rdmsr_safe(MSR_AMD64_SMCA_MCx_MISC(bank), &low, &high))
+		return;
+
+	if (low & MASK_BLKPTR_LO)
+		per_cpu(smca_misc_banks_map, cpu) |= BIT_ULL(bank);
+
+}
+
+static void smca_configure(unsigned int bank, unsigned int cpu)
+{
+	u8 *bank_counts = this_cpu_ptr(smca_bank_counts);
+	const struct smca_hwid *s_hwid;
+	unsigned int i, hwid_mcatype;
+	u32 high, low;
+	u32 smca_config = MSR_AMD64_SMCA_MCx_CONFIG(bank);
+
+	/* Set appropriate bits in MCA_CONFIG */
+	if (!rdmsr_safe(smca_config, &low, &high)) {
+		/*
+		 * OS is required to set the MCAX bit to acknowledge that it is
+		 * now using the new MSR ranges and new registers under each
+		 * bank. It also means that the OS will configure deferred
+		 * errors in the new MCx_CONFIG register. If the bit is not set,
+		 * uncorrectable errors will cause a system panic.
+		 *
+		 * MCA_CONFIG[MCAX] is bit 32 (0 in the high portion of the MSR.)
+		 */
+		high |= BIT(0);
+
+		/*
+		 * SMCA sets the Deferred Error Interrupt type per bank.
+		 *
+		 * MCA_CONFIG[DeferredIntTypeSupported] is bit 5, and tells us
+		 * if the DeferredIntType bit field is available.
+		 *
+		 * MCA_CONFIG[DeferredIntType] is bits [38:37] ([6:5] in the
+		 * high portion of the MSR). OS should set this to 0x1 to enable
+		 * APIC based interrupt. First, check that no interrupt has been
+		 * set.
+		 */
+		if ((low & BIT(5)) && !((high >> 5) & 0x3))
+			high |= BIT(5);
+
+		this_cpu_ptr(mce_banks_array)[bank].lsb_in_status = !!(low & BIT(8));
+
+		wrmsr(smca_config, low, high);
+	}
+
+	smca_set_misc_banks_map(bank, cpu);
+
+	if (rdmsr_safe(MSR_AMD64_SMCA_MCx_IPID(bank), &low, &high)) {
+		pr_warn("Failed to read MCA_IPID for bank %d\n", bank);
+		return;
+	}
+
+	hwid_mcatype = HWID_MCATYPE(high & MCI_IPID_HWID,
+				    (high & MCI_IPID_MCATYPE) >> 16);
+
+	for (i = 0; i < ARRAY_SIZE(smca_hwid_mcatypes); i++) {
+		s_hwid = &smca_hwid_mcatypes[i];
+
+		if (hwid_mcatype == s_hwid->hwid_mcatype) {
+			this_cpu_ptr(smca_banks)[bank].hwid = s_hwid;
+			this_cpu_ptr(smca_banks)[bank].id = low;
+			this_cpu_ptr(smca_banks)[bank].sysfs_id = bank_counts[s_hwid->bank_type]++;
+			break;
+		}
+	}
+}
+
+struct thresh_restart {
+	struct threshold_block	*b;
+	int			reset;
+	int			set_lvt_off;
+	int			lvt_off;
+	u16			old_limit;
+};
+
+static inline bool is_shared_bank(int bank)
+{
+	/*
+	 * Scalable MCA provides for only one core to have access to the MSRs of
+	 * a shared bank.
+	 */
+	if (mce_flags.smca)
+		return false;
+
+	/* Bank 4 is for northbridge reporting and is thus shared */
+	return (bank == 4);
+}
+
+static const char *bank4_names(const struct threshold_block *b)
+{
+	switch (b->address) {
+	/* MSR4_MISC0 */
+	case 0x00000413:
+		return "dram";
+
+	case 0xc0000408:
+		return "ht_links";
+
+	case 0xc0000409:
+		return "l3_cache";
+
+	default:
+		WARN(1, "Funny MSR: 0x%08x\n", b->address);
+		return "";
+	}
+};
+
+
+static bool lvt_interrupt_supported(unsigned int bank, u32 msr_high_bits)
+{
+	/*
+	 * bank 4 supports APIC LVT interrupts implicitly since forever.
+	 */
+	if (bank == 4)
+		return true;
+
+	/*
+	 * IntP: interrupt present; if this bit is set, the thresholding
+	 * bank can generate APIC LVT interrupts
+	 */
+	return msr_high_bits & BIT(28);
+}
+
+static int lvt_off_valid(struct threshold_block *b, int apic, u32 lo, u32 hi)
+{
+	int msr = (hi & MASK_LVTOFF_HI) >> 20;
+
+	if (apic < 0) {
+		pr_err(FW_BUG "cpu %d, failed to setup threshold interrupt "
+		       "for bank %d, block %d (MSR%08X=0x%x%08x)\n", b->cpu,
+		       b->bank, b->block, b->address, hi, lo);
+		return 0;
+	}
+
+	if (apic != msr) {
+		/*
+		 * On SMCA CPUs, LVT offset is programmed at a different MSR, and
+		 * the BIOS provides the value. The original field where LVT offset
+		 * was set is reserved. Return early here:
+		 */
+		if (mce_flags.smca)
+			return 0;
+
+		pr_err(FW_BUG "cpu %d, invalid threshold interrupt offset %d "
+		       "for bank %d, block %d (MSR%08X=0x%x%08x)\n",
+		       b->cpu, apic, b->bank, b->block, b->address, hi, lo);
+		return 0;
+	}
+
+	return 1;
+};
+
+/* Reprogram MCx_MISC MSR behind this threshold bank. */
+static void threshold_restart_bank(void *_tr)
+{
+	struct thresh_restart *tr = _tr;
+	u32 hi, lo;
+
+	/* sysfs write might race against an offline operation */
+	if (!this_cpu_read(threshold_banks) && !tr->set_lvt_off)
+		return;
+
+	rdmsr(tr->b->address, lo, hi);
+
+	if (tr->b->threshold_limit < (hi & THRESHOLD_MAX))
+		tr->reset = 1;	/* limit cannot be lower than err count */
+
+	if (tr->reset) {		/* reset err count and overflow bit */
+		hi =
+		    (hi & ~(MASK_ERR_COUNT_HI | MASK_OVERFLOW_HI)) |
+		    (THRESHOLD_MAX - tr->b->threshold_limit);
+	} else if (tr->old_limit) {	/* change limit w/o reset */
+		int new_count = (hi & THRESHOLD_MAX) +
+		    (tr->old_limit - tr->b->threshold_limit);
+
+		hi = (hi & ~MASK_ERR_COUNT_HI) |
+		    (new_count & THRESHOLD_MAX);
+	}
+
+	/* clear IntType */
+	hi &= ~MASK_INT_TYPE_HI;
+
+	if (!tr->b->interrupt_capable)
+		goto done;
+
+	if (tr->set_lvt_off) {
+		if (lvt_off_valid(tr->b, tr->lvt_off, lo, hi)) {
+			/* set new lvt offset */
+			hi &= ~MASK_LVTOFF_HI;
+			hi |= tr->lvt_off << 20;
+		}
+	}
+
+	if (tr->b->interrupt_enable)
+		hi |= INT_TYPE_APIC;
+
+ done:
+
+	hi |= MASK_COUNT_EN_HI;
+	wrmsr(tr->b->address, lo, hi);
+}
+
+static void mce_threshold_block_init(struct threshold_block *b, int offset)
+{
+	struct thresh_restart tr = {
+		.b			= b,
+		.set_lvt_off		= 1,
+		.lvt_off		= offset,
+	};
+
+	b->threshold_limit		= THRESHOLD_MAX;
+	threshold_restart_bank(&tr);
+};
+
+static int setup_APIC_mce_threshold(int reserved, int new)
+{
+	if (reserved < 0 && !setup_APIC_eilvt(new, THRESHOLD_APIC_VECTOR,
+					      APIC_EILVT_MSG_FIX, 0))
+		return new;
+
+	return reserved;
+}
+
+static int setup_APIC_deferred_error(int reserved, int new)
+{
+	if (reserved < 0 && !setup_APIC_eilvt(new, DEFERRED_ERROR_VECTOR,
+					      APIC_EILVT_MSG_FIX, 0))
+		return new;
+
+	return reserved;
+}
+
+static void deferred_error_interrupt_enable(struct cpuinfo_x86 *c)
+{
+	u32 low = 0, high = 0;
+	int def_offset = -1, def_new;
+
+	if (rdmsr_safe(MSR_CU_DEF_ERR, &low, &high))
+		return;
+
+	def_new = (low & MASK_DEF_LVTOFF) >> 4;
+	if (!(low & MASK_DEF_LVTOFF)) {
+		pr_err(FW_BUG "Your BIOS is not setting up LVT offset 0x2 for deferred error IRQs correctly.\n");
+		def_new = DEF_LVT_OFF;
+		low = (low & ~MASK_DEF_LVTOFF) | (DEF_LVT_OFF << 4);
+	}
+
+	def_offset = setup_APIC_deferred_error(def_offset, def_new);
+	if ((def_offset == def_new) &&
+	    (deferred_error_int_vector != amd_deferred_error_interrupt))
+		deferred_error_int_vector = amd_deferred_error_interrupt;
+
+	if (!mce_flags.smca)
+		low = (low & ~MASK_DEF_INT_TYPE) | DEF_INT_TYPE_APIC;
+
+	wrmsr(MSR_CU_DEF_ERR, low, high);
+}
+
+static u32 smca_get_block_address(unsigned int bank, unsigned int block,
+				  unsigned int cpu)
+{
+	if (!block)
+		return MSR_AMD64_SMCA_MCx_MISC(bank);
+
+	if (!(per_cpu(smca_misc_banks_map, cpu) & BIT_ULL(bank)))
+		return 0;
+
+	return MSR_AMD64_SMCA_MCx_MISCy(bank, block - 1);
+}
+
+static u32 get_block_address(u32 current_addr, u32 low, u32 high,
+			     unsigned int bank, unsigned int block,
+			     unsigned int cpu)
+{
+	u32 addr = 0, offset = 0;
+
+	if ((bank >= per_cpu(mce_num_banks, cpu)) || (block >= NR_BLOCKS))
+		return addr;
+
+	if (mce_flags.smca)
+		return smca_get_block_address(bank, block, cpu);
+
+	/* Fall back to method we used for older processors: */
+	switch (block) {
+	case 0:
+		addr = mca_msr_reg(bank, MCA_MISC);
+		break;
+	case 1:
+		offset = ((low & MASK_BLKPTR_LO) >> 21);
+		if (offset)
+			addr = MCG_XBLK_ADDR + offset;
+		break;
+	default:
+		addr = ++current_addr;
+	}
+	return addr;
+}
+
+static int
+prepare_threshold_block(unsigned int bank, unsigned int block, u32 addr,
+			int offset, u32 misc_high)
+{
+	unsigned int cpu = smp_processor_id();
+	u32 smca_low, smca_high;
+	struct threshold_block b;
+	int new;
+
+	if (!block)
+		per_cpu(bank_map, cpu) |= BIT_ULL(bank);
+
+	memset(&b, 0, sizeof(b));
+	b.cpu			= cpu;
+	b.bank			= bank;
+	b.block			= block;
+	b.address		= addr;
+	b.interrupt_capable	= lvt_interrupt_supported(bank, misc_high);
+
+	if (!b.interrupt_capable)
+		goto done;
+
+	b.interrupt_enable = 1;
+
+	if (!mce_flags.smca) {
+		new = (misc_high & MASK_LVTOFF_HI) >> 20;
+		goto set_offset;
+	}
+
+	/* Gather LVT offset for thresholding: */
+	if (rdmsr_safe(MSR_CU_DEF_ERR, &smca_low, &smca_high))
+		goto out;
+
+	new = (smca_low & SMCA_THR_LVT_OFF) >> 12;
+
+set_offset:
+	offset = setup_APIC_mce_threshold(offset, new);
+	if (offset == new)
+		thresholding_irq_en = true;
+
+done:
+	mce_threshold_block_init(&b, offset);
+
+out:
+	return offset;
+}
+
+bool amd_filter_mce(struct mce *m)
+{
+	enum smca_bank_types bank_type = smca_get_bank_type(m->extcpu, m->bank);
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+
+	/* See Family 17h Models 10h-2Fh Erratum #1114. */
+	if (c->x86 == 0x17 &&
+	    c->x86_model >= 0x10 && c->x86_model <= 0x2F &&
+	    bank_type == SMCA_IF && XEC(m->status, 0x3f) == 10)
+		return true;
+
+	/* NB GART TLB error reporting is disabled by default. */
+	if (c->x86 < 0x17) {
+		if (m->bank == 4 && XEC(m->status, 0x1f) == 0x5)
+			return true;
+	}
+
+	return false;
+}
+
+/*
+ * Turn off thresholding banks for the following conditions:
+ * - MC4_MISC thresholding is not supported on Family 0x15.
+ * - Prevent possible spurious interrupts from the IF bank on Family 0x17
+ *   Models 0x10-0x2F due to Erratum #1114.
+ */
+static void disable_err_thresholding(struct cpuinfo_x86 *c, unsigned int bank)
+{
+	int i, num_msrs;
+	u64 hwcr;
+	bool need_toggle;
+	u32 msrs[NR_BLOCKS];
+
+	if (c->x86 == 0x15 && bank == 4) {
+		msrs[0] = 0x00000413; /* MC4_MISC0 */
+		msrs[1] = 0xc0000408; /* MC4_MISC1 */
+		num_msrs = 2;
+	} else if (c->x86 == 0x17 &&
+		   (c->x86_model >= 0x10 && c->x86_model <= 0x2F)) {
+
+		if (smca_get_bank_type(smp_processor_id(), bank) != SMCA_IF)
+			return;
+
+		msrs[0] = MSR_AMD64_SMCA_MCx_MISC(bank);
+		num_msrs = 1;
+	} else {
+		return;
+	}
+
+	rdmsrl(MSR_K7_HWCR, hwcr);
+
+	/* McStatusWrEn has to be set */
+	need_toggle = !(hwcr & BIT(18));
+	if (need_toggle)
+		wrmsrl(MSR_K7_HWCR, hwcr | BIT(18));
+
+	/* Clear CntP bit safely */
+	for (i = 0; i < num_msrs; i++)
+		msr_clear_bit(msrs[i], 62);
+
+	/* restore old settings */
+	if (need_toggle)
+		wrmsrl(MSR_K7_HWCR, hwcr);
+}
+
+/* cpu init entry point, called from mce.c with preempt off */
+void mce_amd_feature_init(struct cpuinfo_x86 *c)
+{
+	unsigned int bank, block, cpu = smp_processor_id();
+	u32 low = 0, high = 0, address = 0;
+	int offset = -1;
+
+
+	for (bank = 0; bank < this_cpu_read(mce_num_banks); ++bank) {
+		if (mce_flags.smca)
+			smca_configure(bank, cpu);
+
+		disable_err_thresholding(c, bank);
+
+		for (block = 0; block < NR_BLOCKS; ++block) {
+			address = get_block_address(address, low, high, bank, block, cpu);
+			if (!address)
+				break;
+
+			if (rdmsr_safe(address, &low, &high))
+				break;
+
+			if (!(high & MASK_VALID_HI))
+				continue;
+
+			if (!(high & MASK_CNTP_HI)  ||
+			     (high & MASK_LOCKED_HI))
+				continue;
+
+			offset = prepare_threshold_block(bank, block, address, offset, high);
+		}
+	}
+
+	if (mce_flags.succor)
+		deferred_error_interrupt_enable(c);
+}
+
+bool amd_mce_is_memory_error(struct mce *m)
+{
+	enum smca_bank_types bank_type;
+	/* ErrCodeExt[20:16] */
+	u8 xec = (m->status >> 16) & 0x1f;
+
+	bank_type = smca_get_bank_type(m->extcpu, m->bank);
+	if (mce_flags.smca)
+		return (bank_type == SMCA_UMC || bank_type == SMCA_UMC_V2) && xec == 0x0;
+
+	return m->bank == 4 && xec == 0x8;
+}
+
+static void __log_error(unsigned int bank, u64 status, u64 addr, u64 misc)
+{
+	struct mce m;
+
+	mce_setup(&m);
+
+	m.status = status;
+	m.misc   = misc;
+	m.bank   = bank;
+	m.tsc	 = rdtsc();
+
+	if (m.status & MCI_STATUS_ADDRV) {
+		m.addr = addr;
+
+		smca_extract_err_addr(&m);
+	}
+
+	if (mce_flags.smca) {
+		rdmsrl(MSR_AMD64_SMCA_MCx_IPID(bank), m.ipid);
+
+		if (m.status & MCI_STATUS_SYNDV)
+			rdmsrl(MSR_AMD64_SMCA_MCx_SYND(bank), m.synd);
+	}
+
+	mce_log(&m);
+}
+
+DEFINE_IDTENTRY_SYSVEC(sysvec_deferred_error)
+{
+	trace_deferred_error_apic_entry(DEFERRED_ERROR_VECTOR);
+	inc_irq_stat(irq_deferred_error_count);
+	deferred_error_int_vector();
+	trace_deferred_error_apic_exit(DEFERRED_ERROR_VECTOR);
+	apic_eoi();
+}
+
+/*
+ * Returns true if the logged error is deferred. False, otherwise.
+ */
+static inline bool
+_log_error_bank(unsigned int bank, u32 msr_stat, u32 msr_addr, u64 misc)
+{
+	u64 status, addr = 0;
+
+	rdmsrl(msr_stat, status);
+	if (!(status & MCI_STATUS_VAL))
+		return false;
+
+	if (status & MCI_STATUS_ADDRV)
+		rdmsrl(msr_addr, addr);
+
+	__log_error(bank, status, addr, misc);
+
+	wrmsrl(msr_stat, 0);
+
+	return status & MCI_STATUS_DEFERRED;
+}
+
+static bool _log_error_deferred(unsigned int bank, u32 misc)
+{
+	if (!_log_error_bank(bank, mca_msr_reg(bank, MCA_STATUS),
+			     mca_msr_reg(bank, MCA_ADDR), misc))
+		return false;
+
+	/*
+	 * Non-SMCA systems don't have MCA_DESTAT/MCA_DEADDR registers.
+	 * Return true here to avoid accessing these registers.
+	 */
+	if (!mce_flags.smca)
+		return true;
+
+	/* Clear MCA_DESTAT if the deferred error was logged from MCA_STATUS. */
+	wrmsrl(MSR_AMD64_SMCA_MCx_DESTAT(bank), 0);
+	return true;
+}
+
+/*
+ * We have three scenarios for checking for Deferred errors:
+ *
+ * 1) Non-SMCA systems check MCA_STATUS and log error if found.
+ * 2) SMCA systems check MCA_STATUS. If error is found then log it and also
+ *    clear MCA_DESTAT.
+ * 3) SMCA systems check MCA_DESTAT, if error was not found in MCA_STATUS, and
+ *    log it.
+ */
+static void log_error_deferred(unsigned int bank)
+{
+	if (_log_error_deferred(bank, 0))
+		return;
+
+	/*
+	 * Only deferred errors are logged in MCA_DE{STAT,ADDR} so just check
+	 * for a valid error.
+	 */
+	_log_error_bank(bank, MSR_AMD64_SMCA_MCx_DESTAT(bank),
+			      MSR_AMD64_SMCA_MCx_DEADDR(bank), 0);
+}
+
+/* APIC interrupt handler for deferred errors */
+static void amd_deferred_error_interrupt(void)
+{
+	unsigned int bank;
+
+	for (bank = 0; bank < this_cpu_read(mce_num_banks); ++bank)
+		log_error_deferred(bank);
+}
+
+static void log_error_thresholding(unsigned int bank, u64 misc)
+{
+	_log_error_deferred(bank, misc);
+}
+
+static void log_and_reset_block(struct threshold_block *block)
+{
+	struct thresh_restart tr;
+	u32 low = 0, high = 0;
+
+	if (!block)
+		return;
+
+	if (rdmsr_safe(block->address, &low, &high))
+		return;
+
+	if (!(high & MASK_OVERFLOW_HI))
+		return;
+
+	/* Log the MCE which caused the threshold event. */
+	log_error_thresholding(block->bank, ((u64)high << 32) | low);
+
+	/* Reset threshold block after logging error. */
+	memset(&tr, 0, sizeof(tr));
+	tr.b = block;
+	threshold_restart_bank(&tr);
+}
+
+/*
+ * Threshold interrupt handler will service THRESHOLD_APIC_VECTOR. The interrupt
+ * goes off when error_count reaches threshold_limit.
+ */
+static void amd_threshold_interrupt(void)
+{
+	struct threshold_block *first_block = NULL, *block = NULL, *tmp = NULL;
+	struct threshold_bank **bp = this_cpu_read(threshold_banks);
+	unsigned int bank, cpu = smp_processor_id();
+
+	/*
+	 * Validate that the threshold bank has been initialized already. The
+	 * handler is installed at boot time, but on a hotplug event the
+	 * interrupt might fire before the data has been initialized.
+	 */
+	if (!bp)
+		return;
+
+	for (bank = 0; bank < this_cpu_read(mce_num_banks); ++bank) {
+		if (!(per_cpu(bank_map, cpu) & BIT_ULL(bank)))
+			continue;
+
+		first_block = bp[bank]->blocks;
+		if (!first_block)
+			continue;
+
+		/*
+		 * The first block is also the head of the list. Check it first
+		 * before iterating over the rest.
+		 */
+		log_and_reset_block(first_block);
+		list_for_each_entry_safe(block, tmp, &first_block->miscj, miscj)
+			log_and_reset_block(block);
+	}
+}
+
+/*
+ * Sysfs Interface
+ */
+
+struct threshold_attr {
+	struct attribute attr;
+	ssize_t (*show) (struct threshold_block *, char *);
+	ssize_t (*store) (struct threshold_block *, const char *, size_t count);
+};
+
+#define SHOW_FIELDS(name)						\
+static ssize_t show_ ## name(struct threshold_block *b, char *buf)	\
+{									\
+	return sprintf(buf, "%lu\n", (unsigned long) b->name);		\
+}
+SHOW_FIELDS(interrupt_enable)
+SHOW_FIELDS(threshold_limit)
+
+static ssize_t
+store_interrupt_enable(struct threshold_block *b, const char *buf, size_t size)
+{
+	struct thresh_restart tr;
+	unsigned long new;
+
+	if (!b->interrupt_capable)
+		return -EINVAL;
+
+	if (kstrtoul(buf, 0, &new) < 0)
+		return -EINVAL;
+
+	b->interrupt_enable = !!new;
+
+	memset(&tr, 0, sizeof(tr));
+	tr.b		= b;
+
+	if (smp_call_function_single(b->cpu, threshold_restart_bank, &tr, 1))
+		return -ENODEV;
+
+	return size;
+}
+
+static ssize_t
+store_threshold_limit(struct threshold_block *b, const char *buf, size_t size)
+{
+	struct thresh_restart tr;
+	unsigned long new;
+
+	if (kstrtoul(buf, 0, &new) < 0)
+		return -EINVAL;
+
+	if (new > THRESHOLD_MAX)
+		new = THRESHOLD_MAX;
+	if (new < 1)
+		new = 1;
+
+	memset(&tr, 0, sizeof(tr));
+	tr.old_limit = b->threshold_limit;
+	b->threshold_limit = new;
+	tr.b = b;
+
+	if (smp_call_function_single(b->cpu, threshold_restart_bank, &tr, 1))
+		return -ENODEV;
+
+	return size;
+}
+
+static ssize_t show_error_count(struct threshold_block *b, char *buf)
+{
+	u32 lo, hi;
+
+	/* CPU might be offline by now */
+	if (rdmsr_on_cpu(b->cpu, b->address, &lo, &hi))
+		return -ENODEV;
+
+	return sprintf(buf, "%u\n", ((hi & THRESHOLD_MAX) -
+				     (THRESHOLD_MAX - b->threshold_limit)));
+}
+
+static struct threshold_attr error_count = {
+	.attr = {.name = __stringify(error_count), .mode = 0444 },
+	.show = show_error_count,
+};
+
+#define RW_ATTR(val)							\
+static struct threshold_attr val = {					\
+	.attr	= {.name = __stringify(val), .mode = 0644 },		\
+	.show	= show_## val,						\
+	.store	= store_## val,						\
+};
+
+RW_ATTR(interrupt_enable);
+RW_ATTR(threshold_limit);
+
+static struct attribute *default_attrs[] = {
+	&threshold_limit.attr,
+	&error_count.attr,
+	NULL,	/* possibly interrupt_enable if supported, see below */
+	NULL,
+};
+ATTRIBUTE_GROUPS(default);
+
+#define to_block(k)	container_of(k, struct threshold_block, kobj)
+#define to_attr(a)	container_of(a, struct threshold_attr, attr)
+
+static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
+{
+	struct threshold_block *b = to_block(kobj);
+	struct threshold_attr *a = to_attr(attr);
+	ssize_t ret;
+
+	ret = a->show ? a->show(b, buf) : -EIO;
+
+	return ret;
+}
+
+static ssize_t store(struct kobject *kobj, struct attribute *attr,
+		     const char *buf, size_t count)
+{
+	struct threshold_block *b = to_block(kobj);
+	struct threshold_attr *a = to_attr(attr);
+	ssize_t ret;
+
+	ret = a->store ? a->store(b, buf, count) : -EIO;
+
+	return ret;
+}
+
+static const struct sysfs_ops threshold_ops = {
+	.show			= show,
+	.store			= store,
+};
+
+static void threshold_block_release(struct kobject *kobj);
+
+static const struct kobj_type threshold_ktype = {
+	.sysfs_ops		= &threshold_ops,
+	.default_groups		= default_groups,
+	.release		= threshold_block_release,
+};
+
+static const char *get_name(unsigned int cpu, unsigned int bank, struct threshold_block *b)
+{
+	enum smca_bank_types bank_type;
+
+	if (!mce_flags.smca) {
+		if (b && bank == 4)
+			return bank4_names(b);
+
+		return th_names[bank];
+	}
+
+	bank_type = smca_get_bank_type(cpu, bank);
+	if (bank_type >= N_SMCA_BANK_TYPES)
+		return NULL;
+
+	if (b && (bank_type == SMCA_UMC || bank_type == SMCA_UMC_V2)) {
+		if (b->block < ARRAY_SIZE(smca_umc_block_names))
+			return smca_umc_block_names[b->block];
+		return NULL;
+	}
+
+	if (per_cpu(smca_bank_counts, cpu)[bank_type] == 1)
+		return smca_get_name(bank_type);
+
+	snprintf(buf_mcatype, MAX_MCATYPE_NAME_LEN,
+		 "%s_%u", smca_get_name(bank_type),
+			  per_cpu(smca_banks, cpu)[bank].sysfs_id);
+	return buf_mcatype;
+}
+
+static int allocate_threshold_blocks(unsigned int cpu, struct threshold_bank *tb,
+				     unsigned int bank, unsigned int block,
+				     u32 address)
+{
+	struct threshold_block *b = NULL;
+	u32 low, high;
+	int err;
+
+	if ((bank >= this_cpu_read(mce_num_banks)) || (block >= NR_BLOCKS))
+		return 0;
+
+	if (rdmsr_safe(address, &low, &high))
+		return 0;
+
+	if (!(high & MASK_VALID_HI)) {
+		if (block)
+			goto recurse;
+		else
+			return 0;
+	}
+
+	if (!(high & MASK_CNTP_HI)  ||
+	     (high & MASK_LOCKED_HI))
+		goto recurse;
+
+	b = kzalloc(sizeof(struct threshold_block), GFP_KERNEL);
+	if (!b)
+		return -ENOMEM;
+
+	b->block		= block;
+	b->bank			= bank;
+	b->cpu			= cpu;
+	b->address		= address;
+	b->interrupt_enable	= 0;
+	b->interrupt_capable	= lvt_interrupt_supported(bank, high);
+	b->threshold_limit	= THRESHOLD_MAX;
+
+	if (b->interrupt_capable) {
+		default_attrs[2] = &interrupt_enable.attr;
+		b->interrupt_enable = 1;
+	} else {
+		default_attrs[2] = NULL;
+	}
+
+	INIT_LIST_HEAD(&b->miscj);
+
+	/* This is safe as @tb is not visible yet */
+	if (tb->blocks)
+		list_add(&b->miscj, &tb->blocks->miscj);
+	else
+		tb->blocks = b;
+
+	err = kobject_init_and_add(&b->kobj, &threshold_ktype, tb->kobj, get_name(cpu, bank, b));
+	if (err)
+		goto out_free;
+recurse:
+	address = get_block_address(address, low, high, bank, ++block, cpu);
+	if (!address)
+		return 0;
+
+	err = allocate_threshold_blocks(cpu, tb, bank, block, address);
+	if (err)
+		goto out_free;
+
+	if (b)
+		kobject_uevent(&b->kobj, KOBJ_ADD);
+
+	return 0;
+
+out_free:
+	if (b) {
+		list_del(&b->miscj);
+		kobject_put(&b->kobj);
+	}
+	return err;
+}
+
+static int __threshold_add_blocks(struct threshold_bank *b)
+{
+	struct list_head *head = &b->blocks->miscj;
+	struct threshold_block *pos = NULL;
+	struct threshold_block *tmp = NULL;
+	int err = 0;
+
+	err = kobject_add(&b->blocks->kobj, b->kobj, b->blocks->kobj.name);
+	if (err)
+		return err;
+
+	list_for_each_entry_safe(pos, tmp, head, miscj) {
+
+		err = kobject_add(&pos->kobj, b->kobj, pos->kobj.name);
+		if (err) {
+			list_for_each_entry_safe_reverse(pos, tmp, head, miscj)
+				kobject_del(&pos->kobj);
+
+			return err;
+		}
+	}
+	return err;
+}
+
+static int threshold_create_bank(struct threshold_bank **bp, unsigned int cpu,
+				 unsigned int bank)
+{
+	struct device *dev = this_cpu_read(mce_device);
+	struct amd_northbridge *nb = NULL;
+	struct threshold_bank *b = NULL;
+	const char *name = get_name(cpu, bank, NULL);
+	int err = 0;
+
+	if (!dev)
+		return -ENODEV;
+
+	if (is_shared_bank(bank)) {
+		nb = node_to_amd_nb(topology_die_id(cpu));
+
+		/* threshold descriptor already initialized on this node? */
+		if (nb && nb->bank4) {
+			/* yes, use it */
+			b = nb->bank4;
+			err = kobject_add(b->kobj, &dev->kobj, name);
+			if (err)
+				goto out;
+
+			bp[bank] = b;
+			refcount_inc(&b->cpus);
+
+			err = __threshold_add_blocks(b);
+
+			goto out;
+		}
+	}
+
+	b = kzalloc(sizeof(struct threshold_bank), GFP_KERNEL);
+	if (!b) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	/* Associate the bank with the per-CPU MCE device */
+	b->kobj = kobject_create_and_add(name, &dev->kobj);
+	if (!b->kobj) {
+		err = -EINVAL;
+		goto out_free;
+	}
+
+	if (is_shared_bank(bank)) {
+		b->shared = 1;
+		refcount_set(&b->cpus, 1);
+
+		/* nb is already initialized, see above */
+		if (nb) {
+			WARN_ON(nb->bank4);
+			nb->bank4 = b;
+		}
+	}
+
+	err = allocate_threshold_blocks(cpu, b, bank, 0, mca_msr_reg(bank, MCA_MISC));
+	if (err)
+		goto out_kobj;
+
+	bp[bank] = b;
+	return 0;
+
+out_kobj:
+	kobject_put(b->kobj);
+out_free:
+	kfree(b);
+out:
+	return err;
+}
+
+static void threshold_block_release(struct kobject *kobj)
+{
+	kfree(to_block(kobj));
+}
+
+static void deallocate_threshold_blocks(struct threshold_bank *bank)
+{
+	struct threshold_block *pos, *tmp;
+
+	list_for_each_entry_safe(pos, tmp, &bank->blocks->miscj, miscj) {
+		list_del(&pos->miscj);
+		kobject_put(&pos->kobj);
+	}
+
+	kobject_put(&bank->blocks->kobj);
+}
+
+static void __threshold_remove_blocks(struct threshold_bank *b)
+{
+	struct threshold_block *pos = NULL;
+	struct threshold_block *tmp = NULL;
+
+	kobject_put(b->kobj);
+
+	list_for_each_entry_safe(pos, tmp, &b->blocks->miscj, miscj)
+		kobject_put(b->kobj);
+}
+
+static void threshold_remove_bank(struct threshold_bank *bank)
+{
+	struct amd_northbridge *nb;
+
+	if (!bank->blocks)
+		goto out_free;
+
+	if (!bank->shared)
+		goto out_dealloc;
+
+	if (!refcount_dec_and_test(&bank->cpus)) {
+		__threshold_remove_blocks(bank);
+		return;
+	} else {
+		/*
+		 * The last CPU on this node using the shared bank is going
+		 * away, remove that bank now.
+		 */
+		nb = node_to_amd_nb(topology_die_id(smp_processor_id()));
+		nb->bank4 = NULL;
+	}
+
+out_dealloc:
+	deallocate_threshold_blocks(bank);
+
+out_free:
+	kobject_put(bank->kobj);
+	kfree(bank);
+}
+
+static void __threshold_remove_device(struct threshold_bank **bp)
+{
+	unsigned int bank, numbanks = this_cpu_read(mce_num_banks);
+
+	for (bank = 0; bank < numbanks; bank++) {
+		if (!bp[bank])
+			continue;
+
+		threshold_remove_bank(bp[bank]);
+		bp[bank] = NULL;
+	}
+	kfree(bp);
+}
+
+int mce_threshold_remove_device(unsigned int cpu)
+{
+	struct threshold_bank **bp = this_cpu_read(threshold_banks);
+
+	if (!bp)
+		return 0;
+
+	/*
+	 * Clear the pointer before cleaning up, so that the interrupt won't
+	 * touch anything of this.
+	 */
+	this_cpu_write(threshold_banks, NULL);
+
+	__threshold_remove_device(bp);
+	return 0;
+}
+
+/**
+ * mce_threshold_create_device - Create the per-CPU MCE threshold device
+ * @cpu:	The plugged in CPU
+ *
+ * Create directories and files for all valid threshold banks.
+ *
+ * This is invoked from the CPU hotplug callback which was installed in
+ * mcheck_init_device(). The invocation happens in context of the hotplug
+ * thread running on @cpu.  The callback is invoked on all CPUs which are
+ * online when the callback is installed or during a real hotplug event.
+ */
+int mce_threshold_create_device(unsigned int cpu)
+{
+	unsigned int numbanks, bank;
+	struct threshold_bank **bp;
+	int err;
+
+	if (!mce_flags.amd_threshold)
+		return 0;
+
+	bp = this_cpu_read(threshold_banks);
+	if (bp)
+		return 0;
+
+	numbanks = this_cpu_read(mce_num_banks);
+	bp = kcalloc(numbanks, sizeof(*bp), GFP_KERNEL);
+	if (!bp)
+		return -ENOMEM;
+
+	for (bank = 0; bank < numbanks; ++bank) {
+		if (!(this_cpu_read(bank_map) & BIT_ULL(bank)))
+			continue;
+		err = threshold_create_bank(bp, cpu, bank);
+		if (err) {
+			__threshold_remove_device(bp);
+			return err;
+		}
+	}
+	this_cpu_write(threshold_banks, bp);
+
+	if (thresholding_irq_en)
+		mce_threshold_vector = amd_threshold_interrupt;
+	return 0;
+}
diff --git a/arch/x86/kernel/cpu/mce/apei.c b/arch/x86/kernel/cpu/mce/apei.c
new file mode 100644
index 0000000000..8ed3417146
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/apei.c
@@ -0,0 +1,216 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Bridge between MCE and APEI
+ *
+ * On some machine, corrected memory errors are reported via APEI
+ * generic hardware error source (GHES) instead of corrected Machine
+ * Check. These corrected memory errors can be reported to user space
+ * through /dev/mcelog via faking a corrected Machine Check, so that
+ * the error memory page can be offlined by /sbin/mcelog if the error
+ * count for one page is beyond the threshold.
+ *
+ * For fatal MCE, save MCE record into persistent storage via ERST, so
+ * that the MCE record can be logged after reboot via ERST.
+ *
+ * Copyright 2010 Intel Corp.
+ *   Author: Huang Ying <ying.huang@intel.com>
+ */
+
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/acpi.h>
+#include <linux/cper.h>
+#include <acpi/apei.h>
+#include <acpi/ghes.h>
+#include <asm/mce.h>
+
+#include "internal.h"
+
+void apei_mce_report_mem_error(int severity, struct cper_sec_mem_err *mem_err)
+{
+	struct mce m;
+	int lsb;
+
+	if (!(mem_err->validation_bits & CPER_MEM_VALID_PA))
+		return;
+
+	/*
+	 * Even if the ->validation_bits are set for address mask,
+	 * to be extra safe, check and reject an error radius '0',
+	 * and fall back to the default page size.
+	 */
+	if (mem_err->validation_bits & CPER_MEM_VALID_PA_MASK)
+		lsb = find_first_bit((void *)&mem_err->physical_addr_mask, PAGE_SHIFT);
+	else
+		lsb = PAGE_SHIFT;
+
+	mce_setup(&m);
+	m.bank = -1;
+	/* Fake a memory read error with unknown channel */
+	m.status = MCI_STATUS_VAL | MCI_STATUS_EN | MCI_STATUS_ADDRV | MCI_STATUS_MISCV | 0x9f;
+	m.misc = (MCI_MISC_ADDR_PHYS << 6) | lsb;
+
+	if (severity >= GHES_SEV_RECOVERABLE)
+		m.status |= MCI_STATUS_UC;
+
+	if (severity >= GHES_SEV_PANIC) {
+		m.status |= MCI_STATUS_PCC;
+		m.tsc = rdtsc();
+	}
+
+	m.addr = mem_err->physical_addr;
+	mce_log(&m);
+}
+EXPORT_SYMBOL_GPL(apei_mce_report_mem_error);
+
+int apei_smca_report_x86_error(struct cper_ia_proc_ctx *ctx_info, u64 lapic_id)
+{
+	const u64 *i_mce = ((const u64 *) (ctx_info + 1));
+	unsigned int cpu;
+	struct mce m;
+
+	if (!boot_cpu_has(X86_FEATURE_SMCA))
+		return -EINVAL;
+
+	/*
+	 * The starting address of the register array extracted from BERT must
+	 * match with the first expected register in the register layout of
+	 * SMCA address space. This address corresponds to banks's MCA_STATUS
+	 * register.
+	 *
+	 * Match any MCi_STATUS register by turning off bank numbers.
+	 */
+	if ((ctx_info->msr_addr & MSR_AMD64_SMCA_MC0_STATUS) !=
+				  MSR_AMD64_SMCA_MC0_STATUS)
+		return -EINVAL;
+
+	/*
+	 * The register array size must be large enough to include all the
+	 * SMCA registers which need to be extracted.
+	 *
+	 * The number of registers in the register array is determined by
+	 * Register Array Size/8 as defined in UEFI spec v2.8, sec N.2.4.2.2.
+	 * The register layout is fixed and currently the raw data in the
+	 * register array includes 6 SMCA registers which the kernel can
+	 * extract.
+	 */
+	if (ctx_info->reg_arr_size < 48)
+		return -EINVAL;
+
+	mce_setup(&m);
+
+	m.extcpu = -1;
+	m.socketid = -1;
+
+	for_each_possible_cpu(cpu) {
+		if (cpu_data(cpu).initial_apicid == lapic_id) {
+			m.extcpu = cpu;
+			m.socketid = cpu_data(m.extcpu).phys_proc_id;
+			break;
+		}
+	}
+
+	m.apicid = lapic_id;
+	m.bank = (ctx_info->msr_addr >> 4) & 0xFF;
+	m.status = *i_mce;
+	m.addr = *(i_mce + 1);
+	m.misc = *(i_mce + 2);
+	/* Skipping MCA_CONFIG */
+	m.ipid = *(i_mce + 4);
+	m.synd = *(i_mce + 5);
+
+	mce_log(&m);
+
+	return 0;
+}
+
+#define CPER_CREATOR_MCE						\
+	GUID_INIT(0x75a574e3, 0x5052, 0x4b29, 0x8a, 0x8e, 0xbe, 0x2c,	\
+		  0x64, 0x90, 0xb8, 0x9d)
+#define CPER_SECTION_TYPE_MCE						\
+	GUID_INIT(0xfe08ffbe, 0x95e4, 0x4be7, 0xbc, 0x73, 0x40, 0x96,	\
+		  0x04, 0x4a, 0x38, 0xfc)
+
+/*
+ * CPER specification (in UEFI specification 2.3 appendix N) requires
+ * byte-packed.
+ */
+struct cper_mce_record {
+	struct cper_record_header hdr;
+	struct cper_section_descriptor sec_hdr;
+	struct mce mce;
+} __packed;
+
+int apei_write_mce(struct mce *m)
+{
+	struct cper_mce_record rcd;
+
+	memset(&rcd, 0, sizeof(rcd));
+	memcpy(rcd.hdr.signature, CPER_SIG_RECORD, CPER_SIG_SIZE);
+	rcd.hdr.revision = CPER_RECORD_REV;
+	rcd.hdr.signature_end = CPER_SIG_END;
+	rcd.hdr.section_count = 1;
+	rcd.hdr.error_severity = CPER_SEV_FATAL;
+	/* timestamp, platform_id, partition_id are all invalid */
+	rcd.hdr.validation_bits = 0;
+	rcd.hdr.record_length = sizeof(rcd);
+	rcd.hdr.creator_id = CPER_CREATOR_MCE;
+	rcd.hdr.notification_type = CPER_NOTIFY_MCE;
+	rcd.hdr.record_id = cper_next_record_id();
+	rcd.hdr.flags = CPER_HW_ERROR_FLAGS_PREVERR;
+
+	rcd.sec_hdr.section_offset = (void *)&rcd.mce - (void *)&rcd;
+	rcd.sec_hdr.section_length = sizeof(rcd.mce);
+	rcd.sec_hdr.revision = CPER_SEC_REV;
+	/* fru_id and fru_text is invalid */
+	rcd.sec_hdr.validation_bits = 0;
+	rcd.sec_hdr.flags = CPER_SEC_PRIMARY;
+	rcd.sec_hdr.section_type = CPER_SECTION_TYPE_MCE;
+	rcd.sec_hdr.section_severity = CPER_SEV_FATAL;
+
+	memcpy(&rcd.mce, m, sizeof(*m));
+
+	return erst_write(&rcd.hdr);
+}
+
+ssize_t apei_read_mce(struct mce *m, u64 *record_id)
+{
+	struct cper_mce_record rcd;
+	int rc, pos;
+
+	rc = erst_get_record_id_begin(&pos);
+	if (rc)
+		return rc;
+retry:
+	rc = erst_get_record_id_next(&pos, record_id);
+	if (rc)
+		goto out;
+	/* no more record */
+	if (*record_id == APEI_ERST_INVALID_RECORD_ID)
+		goto out;
+	rc = erst_read_record(*record_id, &rcd.hdr, sizeof(rcd), sizeof(rcd),
+			&CPER_CREATOR_MCE);
+	/* someone else has cleared the record, try next one */
+	if (rc == -ENOENT)
+		goto retry;
+	else if (rc < 0)
+		goto out;
+
+	memcpy(m, &rcd.mce, sizeof(*m));
+	rc = sizeof(*m);
+out:
+	erst_get_record_id_end();
+
+	return rc;
+}
+
+/* Check whether there is record in ERST */
+int apei_check_mce(void)
+{
+	return erst_get_record_count();
+}
+
+int apei_clear_mce(u64 record_id)
+{
+	return erst_clear(record_id);
+}
diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
new file mode 100644
index 0000000000..6f35f724cc
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -0,0 +1,2871 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Machine check handler.
+ *
+ * K8 parts Copyright 2002,2003 Andi Kleen, SuSE Labs.
+ * Rest from unknown author(s).
+ * 2004 Andi Kleen. Rewrote most of it.
+ * Copyright 2008 Intel Corporation
+ * Author: Andi Kleen
+ */
+
+#include <linux/thread_info.h>
+#include <linux/capability.h>
+#include <linux/miscdevice.h>
+#include <linux/ratelimit.h>
+#include <linux/rcupdate.h>
+#include <linux/kobject.h>
+#include <linux/uaccess.h>
+#include <linux/kdebug.h>
+#include <linux/kernel.h>
+#include <linux/percpu.h>
+#include <linux/string.h>
+#include <linux/device.h>
+#include <linux/syscore_ops.h>
+#include <linux/delay.h>
+#include <linux/ctype.h>
+#include <linux/sched.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/kmod.h>
+#include <linux/poll.h>
+#include <linux/nmi.h>
+#include <linux/cpu.h>
+#include <linux/ras.h>
+#include <linux/smp.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/debugfs.h>
+#include <linux/irq_work.h>
+#include <linux/export.h>
+#include <linux/set_memory.h>
+#include <linux/sync_core.h>
+#include <linux/task_work.h>
+#include <linux/hardirq.h>
+
+#include <asm/intel-family.h>
+#include <asm/processor.h>
+#include <asm/traps.h>
+#include <asm/tlbflush.h>
+#include <asm/mce.h>
+#include <asm/msr.h>
+#include <asm/reboot.h>
+
+#include "internal.h"
+
+/* sysfs synchronization */
+static DEFINE_MUTEX(mce_sysfs_mutex);
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/mce.h>
+
+#define SPINUNIT		100	/* 100ns */
+
+DEFINE_PER_CPU(unsigned, mce_exception_count);
+
+DEFINE_PER_CPU_READ_MOSTLY(unsigned int, mce_num_banks);
+
+DEFINE_PER_CPU_READ_MOSTLY(struct mce_bank[MAX_NR_BANKS], mce_banks_array);
+
+#define ATTR_LEN               16
+/* One object for each MCE bank, shared by all CPUs */
+struct mce_bank_dev {
+	struct device_attribute	attr;			/* device attribute */
+	char			attrname[ATTR_LEN];	/* attribute name */
+	u8			bank;			/* bank number */
+};
+static struct mce_bank_dev mce_bank_devs[MAX_NR_BANKS];
+
+struct mce_vendor_flags mce_flags __read_mostly;
+
+struct mca_config mca_cfg __read_mostly = {
+	.bootlog  = -1,
+	.monarch_timeout = -1
+};
+
+static DEFINE_PER_CPU(struct mce, mces_seen);
+static unsigned long mce_need_notify;
+
+/*
+ * MCA banks polled by the period polling timer for corrected events.
+ * With Intel CMCI, this only has MCA banks which do not support CMCI (if any).
+ */
+DEFINE_PER_CPU(mce_banks_t, mce_poll_banks) = {
+	[0 ... BITS_TO_LONGS(MAX_NR_BANKS)-1] = ~0UL
+};
+
+/*
+ * MCA banks controlled through firmware first for corrected errors.
+ * This is a global list of banks for which we won't enable CMCI and we
+ * won't poll. Firmware controls these banks and is responsible for
+ * reporting corrected errors through GHES. Uncorrected/recoverable
+ * errors are still notified through a machine check.
+ */
+mce_banks_t mce_banks_ce_disabled;
+
+static struct work_struct mce_work;
+static struct irq_work mce_irq_work;
+
+/*
+ * CPU/chipset specific EDAC code can register a notifier call here to print
+ * MCE errors in a human-readable form.
+ */
+BLOCKING_NOTIFIER_HEAD(x86_mce_decoder_chain);
+
+/* Do initial initialization of a struct mce */
+void mce_setup(struct mce *m)
+{
+	memset(m, 0, sizeof(struct mce));
+	m->cpu = m->extcpu = smp_processor_id();
+	/* need the internal __ version to avoid deadlocks */
+	m->time = __ktime_get_real_seconds();
+	m->cpuvendor = boot_cpu_data.x86_vendor;
+	m->cpuid = cpuid_eax(1);
+	m->socketid = cpu_data(m->extcpu).phys_proc_id;
+	m->apicid = cpu_data(m->extcpu).initial_apicid;
+	m->mcgcap = __rdmsr(MSR_IA32_MCG_CAP);
+	m->ppin = cpu_data(m->extcpu).ppin;
+	m->microcode = boot_cpu_data.microcode;
+}
+
+DEFINE_PER_CPU(struct mce, injectm);
+EXPORT_PER_CPU_SYMBOL_GPL(injectm);
+
+void mce_log(struct mce *m)
+{
+	if (!mce_gen_pool_add(m))
+		irq_work_queue(&mce_irq_work);
+}
+EXPORT_SYMBOL_GPL(mce_log);
+
+void mce_register_decode_chain(struct notifier_block *nb)
+{
+	if (WARN_ON(nb->priority < MCE_PRIO_LOWEST ||
+		    nb->priority > MCE_PRIO_HIGHEST))
+		return;
+
+	blocking_notifier_chain_register(&x86_mce_decoder_chain, nb);
+}
+EXPORT_SYMBOL_GPL(mce_register_decode_chain);
+
+void mce_unregister_decode_chain(struct notifier_block *nb)
+{
+	blocking_notifier_chain_unregister(&x86_mce_decoder_chain, nb);
+}
+EXPORT_SYMBOL_GPL(mce_unregister_decode_chain);
+
+static void __print_mce(struct mce *m)
+{
+	pr_emerg(HW_ERR "CPU %d: Machine Check%s: %Lx Bank %d: %016Lx\n",
+		 m->extcpu,
+		 (m->mcgstatus & MCG_STATUS_MCIP ? " Exception" : ""),
+		 m->mcgstatus, m->bank, m->status);
+
+	if (m->ip) {
+		pr_emerg(HW_ERR "RIP%s %02x:<%016Lx> ",
+			!(m->mcgstatus & MCG_STATUS_EIPV) ? " !INEXACT!" : "",
+			m->cs, m->ip);
+
+		if (m->cs == __KERNEL_CS)
+			pr_cont("{%pS}", (void *)(unsigned long)m->ip);
+		pr_cont("\n");
+	}
+
+	pr_emerg(HW_ERR "TSC %llx ", m->tsc);
+	if (m->addr)
+		pr_cont("ADDR %llx ", m->addr);
+	if (m->misc)
+		pr_cont("MISC %llx ", m->misc);
+	if (m->ppin)
+		pr_cont("PPIN %llx ", m->ppin);
+
+	if (mce_flags.smca) {
+		if (m->synd)
+			pr_cont("SYND %llx ", m->synd);
+		if (m->ipid)
+			pr_cont("IPID %llx ", m->ipid);
+	}
+
+	pr_cont("\n");
+
+	/*
+	 * Note this output is parsed by external tools and old fields
+	 * should not be changed.
+	 */
+	pr_emerg(HW_ERR "PROCESSOR %u:%x TIME %llu SOCKET %u APIC %x microcode %x\n",
+		m->cpuvendor, m->cpuid, m->time, m->socketid, m->apicid,
+		m->microcode);
+}
+
+static void print_mce(struct mce *m)
+{
+	__print_mce(m);
+
+	if (m->cpuvendor != X86_VENDOR_AMD && m->cpuvendor != X86_VENDOR_HYGON)
+		pr_emerg_ratelimited(HW_ERR "Run the above through 'mcelog --ascii'\n");
+}
+
+#define PANIC_TIMEOUT 5 /* 5 seconds */
+
+static atomic_t mce_panicked;
+
+static int fake_panic;
+static atomic_t mce_fake_panicked;
+
+/* Panic in progress. Enable interrupts and wait for final IPI */
+static void wait_for_panic(void)
+{
+	long timeout = PANIC_TIMEOUT*USEC_PER_SEC;
+
+	preempt_disable();
+	local_irq_enable();
+	while (timeout-- > 0)
+		udelay(1);
+	if (panic_timeout == 0)
+		panic_timeout = mca_cfg.panic_timeout;
+	panic("Panicing machine check CPU died");
+}
+
+static noinstr void mce_panic(const char *msg, struct mce *final, char *exp)
+{
+	struct llist_node *pending;
+	struct mce_evt_llist *l;
+	int apei_err = 0;
+
+	/*
+	 * Allow instrumentation around external facilities usage. Not that it
+	 * matters a whole lot since the machine is going to panic anyway.
+	 */
+	instrumentation_begin();
+
+	if (!fake_panic) {
+		/*
+		 * Make sure only one CPU runs in machine check panic
+		 */
+		if (atomic_inc_return(&mce_panicked) > 1)
+			wait_for_panic();
+		barrier();
+
+		bust_spinlocks(1);
+		console_verbose();
+	} else {
+		/* Don't log too much for fake panic */
+		if (atomic_inc_return(&mce_fake_panicked) > 1)
+			goto out;
+	}
+	pending = mce_gen_pool_prepare_records();
+	/* First print corrected ones that are still unlogged */
+	llist_for_each_entry(l, pending, llnode) {
+		struct mce *m = &l->mce;
+		if (!(m->status & MCI_STATUS_UC)) {
+			print_mce(m);
+			if (!apei_err)
+				apei_err = apei_write_mce(m);
+		}
+	}
+	/* Now print uncorrected but with the final one last */
+	llist_for_each_entry(l, pending, llnode) {
+		struct mce *m = &l->mce;
+		if (!(m->status & MCI_STATUS_UC))
+			continue;
+		if (!final || mce_cmp(m, final)) {
+			print_mce(m);
+			if (!apei_err)
+				apei_err = apei_write_mce(m);
+		}
+	}
+	if (final) {
+		print_mce(final);
+		if (!apei_err)
+			apei_err = apei_write_mce(final);
+	}
+	if (exp)
+		pr_emerg(HW_ERR "Machine check: %s\n", exp);
+	if (!fake_panic) {
+		if (panic_timeout == 0)
+			panic_timeout = mca_cfg.panic_timeout;
+		panic(msg);
+	} else
+		pr_emerg(HW_ERR "Fake kernel panic: %s\n", msg);
+
+out:
+	instrumentation_end();
+}
+
+/* Support code for software error injection */
+
+static int msr_to_offset(u32 msr)
+{
+	unsigned bank = __this_cpu_read(injectm.bank);
+
+	if (msr == mca_cfg.rip_msr)
+		return offsetof(struct mce, ip);
+	if (msr == mca_msr_reg(bank, MCA_STATUS))
+		return offsetof(struct mce, status);
+	if (msr == mca_msr_reg(bank, MCA_ADDR))
+		return offsetof(struct mce, addr);
+	if (msr == mca_msr_reg(bank, MCA_MISC))
+		return offsetof(struct mce, misc);
+	if (msr == MSR_IA32_MCG_STATUS)
+		return offsetof(struct mce, mcgstatus);
+	return -1;
+}
+
+void ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr)
+{
+	if (wrmsr) {
+		pr_emerg("MSR access error: WRMSR to 0x%x (tried to write 0x%08x%08x) at rIP: 0x%lx (%pS)\n",
+			 (unsigned int)regs->cx, (unsigned int)regs->dx, (unsigned int)regs->ax,
+			 regs->ip, (void *)regs->ip);
+	} else {
+		pr_emerg("MSR access error: RDMSR from 0x%x at rIP: 0x%lx (%pS)\n",
+			 (unsigned int)regs->cx, regs->ip, (void *)regs->ip);
+	}
+
+	show_stack_regs(regs);
+
+	panic("MCA architectural violation!\n");
+
+	while (true)
+		cpu_relax();
+}
+
+/* MSR access wrappers used for error injection */
+noinstr u64 mce_rdmsrl(u32 msr)
+{
+	DECLARE_ARGS(val, low, high);
+
+	if (__this_cpu_read(injectm.finished)) {
+		int offset;
+		u64 ret;
+
+		instrumentation_begin();
+
+		offset = msr_to_offset(msr);
+		if (offset < 0)
+			ret = 0;
+		else
+			ret = *(u64 *)((char *)this_cpu_ptr(&injectm) + offset);
+
+		instrumentation_end();
+
+		return ret;
+	}
+
+	/*
+	 * RDMSR on MCA MSRs should not fault. If they do, this is very much an
+	 * architectural violation and needs to be reported to hw vendor. Panic
+	 * the box to not allow any further progress.
+	 */
+	asm volatile("1: rdmsr\n"
+		     "2:\n"
+		     _ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_RDMSR_IN_MCE)
+		     : EAX_EDX_RET(val, low, high) : "c" (msr));
+
+
+	return EAX_EDX_VAL(val, low, high);
+}
+
+static noinstr void mce_wrmsrl(u32 msr, u64 v)
+{
+	u32 low, high;
+
+	if (__this_cpu_read(injectm.finished)) {
+		int offset;
+
+		instrumentation_begin();
+
+		offset = msr_to_offset(msr);
+		if (offset >= 0)
+			*(u64 *)((char *)this_cpu_ptr(&injectm) + offset) = v;
+
+		instrumentation_end();
+
+		return;
+	}
+
+	low  = (u32)v;
+	high = (u32)(v >> 32);
+
+	/* See comment in mce_rdmsrl() */
+	asm volatile("1: wrmsr\n"
+		     "2:\n"
+		     _ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_WRMSR_IN_MCE)
+		     : : "c" (msr), "a"(low), "d" (high) : "memory");
+}
+
+/*
+ * Collect all global (w.r.t. this processor) status about this machine
+ * check into our "mce" struct so that we can use it later to assess
+ * the severity of the problem as we read per-bank specific details.
+ */
+static noinstr void mce_gather_info(struct mce *m, struct pt_regs *regs)
+{
+	/*
+	 * Enable instrumentation around mce_setup() which calls external
+	 * facilities.
+	 */
+	instrumentation_begin();
+	mce_setup(m);
+	instrumentation_end();
+
+	m->mcgstatus = mce_rdmsrl(MSR_IA32_MCG_STATUS);
+	if (regs) {
+		/*
+		 * Get the address of the instruction at the time of
+		 * the machine check error.
+		 */
+		if (m->mcgstatus & (MCG_STATUS_RIPV|MCG_STATUS_EIPV)) {
+			m->ip = regs->ip;
+			m->cs = regs->cs;
+
+			/*
+			 * When in VM86 mode make the cs look like ring 3
+			 * always. This is a lie, but it's better than passing
+			 * the additional vm86 bit around everywhere.
+			 */
+			if (v8086_mode(regs))
+				m->cs |= 3;
+		}
+		/* Use accurate RIP reporting if available. */
+		if (mca_cfg.rip_msr)
+			m->ip = mce_rdmsrl(mca_cfg.rip_msr);
+	}
+}
+
+int mce_available(struct cpuinfo_x86 *c)
+{
+	if (mca_cfg.disabled)
+		return 0;
+	return cpu_has(c, X86_FEATURE_MCE) && cpu_has(c, X86_FEATURE_MCA);
+}
+
+static void mce_schedule_work(void)
+{
+	if (!mce_gen_pool_empty())
+		schedule_work(&mce_work);
+}
+
+static void mce_irq_work_cb(struct irq_work *entry)
+{
+	mce_schedule_work();
+}
+
+/*
+ * Check if the address reported by the CPU is in a format we can parse.
+ * It would be possible to add code for most other cases, but all would
+ * be somewhat complicated (e.g. segment offset would require an instruction
+ * parser). So only support physical addresses up to page granularity for now.
+ */
+int mce_usable_address(struct mce *m)
+{
+	if (!(m->status & MCI_STATUS_ADDRV))
+		return 0;
+
+	/* Checks after this one are Intel/Zhaoxin-specific: */
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL &&
+	    boot_cpu_data.x86_vendor != X86_VENDOR_ZHAOXIN)
+		return 1;
+
+	if (!(m->status & MCI_STATUS_MISCV))
+		return 0;
+
+	if (MCI_MISC_ADDR_LSB(m->misc) > PAGE_SHIFT)
+		return 0;
+
+	if (MCI_MISC_ADDR_MODE(m->misc) != MCI_MISC_ADDR_PHYS)
+		return 0;
+
+	return 1;
+}
+EXPORT_SYMBOL_GPL(mce_usable_address);
+
+bool mce_is_memory_error(struct mce *m)
+{
+	switch (m->cpuvendor) {
+	case X86_VENDOR_AMD:
+	case X86_VENDOR_HYGON:
+		return amd_mce_is_memory_error(m);
+
+	case X86_VENDOR_INTEL:
+	case X86_VENDOR_ZHAOXIN:
+		/*
+		 * Intel SDM Volume 3B - 15.9.2 Compound Error Codes
+		 *
+		 * Bit 7 of the MCACOD field of IA32_MCi_STATUS is used for
+		 * indicating a memory error. Bit 8 is used for indicating a
+		 * cache hierarchy error. The combination of bit 2 and bit 3
+		 * is used for indicating a `generic' cache hierarchy error
+		 * But we can't just blindly check the above bits, because if
+		 * bit 11 is set, then it is a bus/interconnect error - and
+		 * either way the above bits just gives more detail on what
+		 * bus/interconnect error happened. Note that bit 12 can be
+		 * ignored, as it's the "filter" bit.
+		 */
+		return (m->status & 0xef80) == BIT(7) ||
+		       (m->status & 0xef00) == BIT(8) ||
+		       (m->status & 0xeffc) == 0xc;
+
+	default:
+		return false;
+	}
+}
+EXPORT_SYMBOL_GPL(mce_is_memory_error);
+
+static bool whole_page(struct mce *m)
+{
+	if (!mca_cfg.ser || !(m->status & MCI_STATUS_MISCV))
+		return true;
+
+	return MCI_MISC_ADDR_LSB(m->misc) >= PAGE_SHIFT;
+}
+
+bool mce_is_correctable(struct mce *m)
+{
+	if (m->cpuvendor == X86_VENDOR_AMD && m->status & MCI_STATUS_DEFERRED)
+		return false;
+
+	if (m->cpuvendor == X86_VENDOR_HYGON && m->status & MCI_STATUS_DEFERRED)
+		return false;
+
+	if (m->status & MCI_STATUS_UC)
+		return false;
+
+	return true;
+}
+EXPORT_SYMBOL_GPL(mce_is_correctable);
+
+static int mce_early_notifier(struct notifier_block *nb, unsigned long val,
+			      void *data)
+{
+	struct mce *m = (struct mce *)data;
+
+	if (!m)
+		return NOTIFY_DONE;
+
+	/* Emit the trace record: */
+	trace_mce_record(m);
+
+	set_bit(0, &mce_need_notify);
+
+	mce_notify_irq();
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block early_nb = {
+	.notifier_call	= mce_early_notifier,
+	.priority	= MCE_PRIO_EARLY,
+};
+
+static int uc_decode_notifier(struct notifier_block *nb, unsigned long val,
+			      void *data)
+{
+	struct mce *mce = (struct mce *)data;
+	unsigned long pfn;
+
+	if (!mce || !mce_usable_address(mce))
+		return NOTIFY_DONE;
+
+	if (mce->severity != MCE_AO_SEVERITY &&
+	    mce->severity != MCE_DEFERRED_SEVERITY)
+		return NOTIFY_DONE;
+
+	pfn = (mce->addr & MCI_ADDR_PHYSADDR) >> PAGE_SHIFT;
+	if (!memory_failure(pfn, 0)) {
+		set_mce_nospec(pfn);
+		mce->kflags |= MCE_HANDLED_UC;
+	}
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block mce_uc_nb = {
+	.notifier_call	= uc_decode_notifier,
+	.priority	= MCE_PRIO_UC,
+};
+
+static int mce_default_notifier(struct notifier_block *nb, unsigned long val,
+				void *data)
+{
+	struct mce *m = (struct mce *)data;
+
+	if (!m)
+		return NOTIFY_DONE;
+
+	if (mca_cfg.print_all || !m->kflags)
+		__print_mce(m);
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block mce_default_nb = {
+	.notifier_call	= mce_default_notifier,
+	/* lowest prio, we want it to run last. */
+	.priority	= MCE_PRIO_LOWEST,
+};
+
+/*
+ * Read ADDR and MISC registers.
+ */
+static noinstr void mce_read_aux(struct mce *m, int i)
+{
+	if (m->status & MCI_STATUS_MISCV)
+		m->misc = mce_rdmsrl(mca_msr_reg(i, MCA_MISC));
+
+	if (m->status & MCI_STATUS_ADDRV) {
+		m->addr = mce_rdmsrl(mca_msr_reg(i, MCA_ADDR));
+
+		/*
+		 * Mask the reported address by the reported granularity.
+		 */
+		if (mca_cfg.ser && (m->status & MCI_STATUS_MISCV)) {
+			u8 shift = MCI_MISC_ADDR_LSB(m->misc);
+			m->addr >>= shift;
+			m->addr <<= shift;
+		}
+
+		smca_extract_err_addr(m);
+	}
+
+	if (mce_flags.smca) {
+		m->ipid = mce_rdmsrl(MSR_AMD64_SMCA_MCx_IPID(i));
+
+		if (m->status & MCI_STATUS_SYNDV)
+			m->synd = mce_rdmsrl(MSR_AMD64_SMCA_MCx_SYND(i));
+	}
+}
+
+DEFINE_PER_CPU(unsigned, mce_poll_count);
+
+/*
+ * Poll for corrected events or events that happened before reset.
+ * Those are just logged through /dev/mcelog.
+ *
+ * This is executed in standard interrupt context.
+ *
+ * Note: spec recommends to panic for fatal unsignalled
+ * errors here. However this would be quite problematic --
+ * we would need to reimplement the Monarch handling and
+ * it would mess up the exclusion between exception handler
+ * and poll handler -- * so we skip this for now.
+ * These cases should not happen anyways, or only when the CPU
+ * is already totally * confused. In this case it's likely it will
+ * not fully execute the machine check handler either.
+ */
+bool machine_check_poll(enum mcp_flags flags, mce_banks_t *b)
+{
+	struct mce_bank *mce_banks = this_cpu_ptr(mce_banks_array);
+	bool error_seen = false;
+	struct mce m;
+	int i;
+
+	this_cpu_inc(mce_poll_count);
+
+	mce_gather_info(&m, NULL);
+
+	if (flags & MCP_TIMESTAMP)
+		m.tsc = rdtsc();
+
+	for (i = 0; i < this_cpu_read(mce_num_banks); i++) {
+		if (!mce_banks[i].ctl || !test_bit(i, *b))
+			continue;
+
+		m.misc = 0;
+		m.addr = 0;
+		m.bank = i;
+
+		barrier();
+		m.status = mce_rdmsrl(mca_msr_reg(i, MCA_STATUS));
+
+		/* If this entry is not valid, ignore it */
+		if (!(m.status & MCI_STATUS_VAL))
+			continue;
+
+		/*
+		 * If we are logging everything (at CPU online) or this
+		 * is a corrected error, then we must log it.
+		 */
+		if ((flags & MCP_UC) || !(m.status & MCI_STATUS_UC))
+			goto log_it;
+
+		/*
+		 * Newer Intel systems that support software error
+		 * recovery need to make additional checks. Other
+		 * CPUs should skip over uncorrected errors, but log
+		 * everything else.
+		 */
+		if (!mca_cfg.ser) {
+			if (m.status & MCI_STATUS_UC)
+				continue;
+			goto log_it;
+		}
+
+		/* Log "not enabled" (speculative) errors */
+		if (!(m.status & MCI_STATUS_EN))
+			goto log_it;
+
+		/*
+		 * Log UCNA (SDM: 15.6.3 "UCR Error Classification")
+		 * UC == 1 && PCC == 0 && S == 0
+		 */
+		if (!(m.status & MCI_STATUS_PCC) && !(m.status & MCI_STATUS_S))
+			goto log_it;
+
+		/*
+		 * Skip anything else. Presumption is that our read of this
+		 * bank is racing with a machine check. Leave the log alone
+		 * for do_machine_check() to deal with it.
+		 */
+		continue;
+
+log_it:
+		error_seen = true;
+
+		if (flags & MCP_DONTLOG)
+			goto clear_it;
+
+		mce_read_aux(&m, i);
+		m.severity = mce_severity(&m, NULL, NULL, false);
+		/*
+		 * Don't get the IP here because it's unlikely to
+		 * have anything to do with the actual error location.
+		 */
+
+		if (mca_cfg.dont_log_ce && !mce_usable_address(&m))
+			goto clear_it;
+
+		if (flags & MCP_QUEUE_LOG)
+			mce_gen_pool_add(&m);
+		else
+			mce_log(&m);
+
+clear_it:
+		/*
+		 * Clear state for this bank.
+		 */
+		mce_wrmsrl(mca_msr_reg(i, MCA_STATUS), 0);
+	}
+
+	/*
+	 * Don't clear MCG_STATUS here because it's only defined for
+	 * exceptions.
+	 */
+
+	sync_core();
+
+	return error_seen;
+}
+EXPORT_SYMBOL_GPL(machine_check_poll);
+
+/*
+ * During IFU recovery Sandy Bridge -EP4S processors set the RIPV and
+ * EIPV bits in MCG_STATUS to zero on the affected logical processor (SDM
+ * Vol 3B Table 15-20). But this confuses both the code that determines
+ * whether the machine check occurred in kernel or user mode, and also
+ * the severity assessment code. Pretend that EIPV was set, and take the
+ * ip/cs values from the pt_regs that mce_gather_info() ignored earlier.
+ */
+static __always_inline void
+quirk_sandybridge_ifu(int bank, struct mce *m, struct pt_regs *regs)
+{
+	if (bank != 0)
+		return;
+	if ((m->mcgstatus & (MCG_STATUS_EIPV|MCG_STATUS_RIPV)) != 0)
+		return;
+	if ((m->status & (MCI_STATUS_OVER|MCI_STATUS_UC|
+		          MCI_STATUS_EN|MCI_STATUS_MISCV|MCI_STATUS_ADDRV|
+			  MCI_STATUS_PCC|MCI_STATUS_S|MCI_STATUS_AR|
+			  MCACOD)) !=
+			 (MCI_STATUS_UC|MCI_STATUS_EN|
+			  MCI_STATUS_MISCV|MCI_STATUS_ADDRV|MCI_STATUS_S|
+			  MCI_STATUS_AR|MCACOD_INSTR))
+		return;
+
+	m->mcgstatus |= MCG_STATUS_EIPV;
+	m->ip = regs->ip;
+	m->cs = regs->cs;
+}
+
+/*
+ * Disable fast string copy and return from the MCE handler upon the first SRAR
+ * MCE on bank 1 due to a CPU erratum on Intel Skylake/Cascade Lake/Cooper Lake
+ * CPUs.
+ * The fast string copy instructions ("REP; MOVS*") could consume an
+ * uncorrectable memory error in the cache line _right after_ the desired region
+ * to copy and raise an MCE with RIP pointing to the instruction _after_ the
+ * "REP; MOVS*".
+ * This mitigation addresses the issue completely with the caveat of performance
+ * degradation on the CPU affected. This is still better than the OS crashing on
+ * MCEs raised on an irrelevant process due to "REP; MOVS*" accesses from a
+ * kernel context (e.g., copy_page).
+ *
+ * Returns true when fast string copy on CPU has been disabled.
+ */
+static noinstr bool quirk_skylake_repmov(void)
+{
+	u64 mcgstatus   = mce_rdmsrl(MSR_IA32_MCG_STATUS);
+	u64 misc_enable = mce_rdmsrl(MSR_IA32_MISC_ENABLE);
+	u64 mc1_status;
+
+	/*
+	 * Apply the quirk only to local machine checks, i.e., no broadcast
+	 * sync is needed.
+	 */
+	if (!(mcgstatus & MCG_STATUS_LMCES) ||
+	    !(misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING))
+		return false;
+
+	mc1_status = mce_rdmsrl(MSR_IA32_MCx_STATUS(1));
+
+	/* Check for a software-recoverable data fetch error. */
+	if ((mc1_status &
+	     (MCI_STATUS_VAL | MCI_STATUS_OVER | MCI_STATUS_UC | MCI_STATUS_EN |
+	      MCI_STATUS_ADDRV | MCI_STATUS_MISCV | MCI_STATUS_PCC |
+	      MCI_STATUS_AR | MCI_STATUS_S)) ==
+	     (MCI_STATUS_VAL |                   MCI_STATUS_UC | MCI_STATUS_EN |
+	      MCI_STATUS_ADDRV | MCI_STATUS_MISCV |
+	      MCI_STATUS_AR | MCI_STATUS_S)) {
+		misc_enable &= ~MSR_IA32_MISC_ENABLE_FAST_STRING;
+		mce_wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
+		mce_wrmsrl(MSR_IA32_MCx_STATUS(1), 0);
+
+		instrumentation_begin();
+		pr_err_once("Erratum detected, disable fast string copy instructions.\n");
+		instrumentation_end();
+
+		return true;
+	}
+
+	return false;
+}
+
+/*
+ * Some Zen-based Instruction Fetch Units set EIPV=RIPV=0 on poison consumption
+ * errors. This means mce_gather_info() will not save the "ip" and "cs" registers.
+ *
+ * However, the context is still valid, so save the "cs" register for later use.
+ *
+ * The "ip" register is truly unknown, so don't save it or fixup EIPV/RIPV.
+ *
+ * The Instruction Fetch Unit is at MCA bank 1 for all affected systems.
+ */
+static __always_inline void quirk_zen_ifu(int bank, struct mce *m, struct pt_regs *regs)
+{
+	if (bank != 1)
+		return;
+	if (!(m->status & MCI_STATUS_POISON))
+		return;
+
+	m->cs = regs->cs;
+}
+
+/*
+ * Do a quick check if any of the events requires a panic.
+ * This decides if we keep the events around or clear them.
+ */
+static __always_inline int mce_no_way_out(struct mce *m, char **msg, unsigned long *validp,
+					  struct pt_regs *regs)
+{
+	char *tmp = *msg;
+	int i;
+
+	for (i = 0; i < this_cpu_read(mce_num_banks); i++) {
+		m->status = mce_rdmsrl(mca_msr_reg(i, MCA_STATUS));
+		if (!(m->status & MCI_STATUS_VAL))
+			continue;
+
+		arch___set_bit(i, validp);
+		if (mce_flags.snb_ifu_quirk)
+			quirk_sandybridge_ifu(i, m, regs);
+
+		if (mce_flags.zen_ifu_quirk)
+			quirk_zen_ifu(i, m, regs);
+
+		m->bank = i;
+		if (mce_severity(m, regs, &tmp, true) >= MCE_PANIC_SEVERITY) {
+			mce_read_aux(m, i);
+			*msg = tmp;
+			return 1;
+		}
+	}
+	return 0;
+}
+
+/*
+ * Variable to establish order between CPUs while scanning.
+ * Each CPU spins initially until executing is equal its number.
+ */
+static atomic_t mce_executing;
+
+/*
+ * Defines order of CPUs on entry. First CPU becomes Monarch.
+ */
+static atomic_t mce_callin;
+
+/*
+ * Track which CPUs entered the MCA broadcast synchronization and which not in
+ * order to print holdouts.
+ */
+static cpumask_t mce_missing_cpus = CPU_MASK_ALL;
+
+/*
+ * Check if a timeout waiting for other CPUs happened.
+ */
+static noinstr int mce_timed_out(u64 *t, const char *msg)
+{
+	int ret = 0;
+
+	/* Enable instrumentation around calls to external facilities */
+	instrumentation_begin();
+
+	/*
+	 * The others already did panic for some reason.
+	 * Bail out like in a timeout.
+	 * rmb() to tell the compiler that system_state
+	 * might have been modified by someone else.
+	 */
+	rmb();
+	if (atomic_read(&mce_panicked))
+		wait_for_panic();
+	if (!mca_cfg.monarch_timeout)
+		goto out;
+	if ((s64)*t < SPINUNIT) {
+		if (cpumask_and(&mce_missing_cpus, cpu_online_mask, &mce_missing_cpus))
+			pr_emerg("CPUs not responding to MCE broadcast (may include false positives): %*pbl\n",
+				 cpumask_pr_args(&mce_missing_cpus));
+		mce_panic(msg, NULL, NULL);
+
+		ret = 1;
+		goto out;
+	}
+	*t -= SPINUNIT;
+
+out:
+	touch_nmi_watchdog();
+
+	instrumentation_end();
+
+	return ret;
+}
+
+/*
+ * The Monarch's reign.  The Monarch is the CPU who entered
+ * the machine check handler first. It waits for the others to
+ * raise the exception too and then grades them. When any
+ * error is fatal panic. Only then let the others continue.
+ *
+ * The other CPUs entering the MCE handler will be controlled by the
+ * Monarch. They are called Subjects.
+ *
+ * This way we prevent any potential data corruption in a unrecoverable case
+ * and also makes sure always all CPU's errors are examined.
+ *
+ * Also this detects the case of a machine check event coming from outer
+ * space (not detected by any CPUs) In this case some external agent wants
+ * us to shut down, so panic too.
+ *
+ * The other CPUs might still decide to panic if the handler happens
+ * in a unrecoverable place, but in this case the system is in a semi-stable
+ * state and won't corrupt anything by itself. It's ok to let the others
+ * continue for a bit first.
+ *
+ * All the spin loops have timeouts; when a timeout happens a CPU
+ * typically elects itself to be Monarch.
+ */
+static void mce_reign(void)
+{
+	int cpu;
+	struct mce *m = NULL;
+	int global_worst = 0;
+	char *msg = NULL;
+
+	/*
+	 * This CPU is the Monarch and the other CPUs have run
+	 * through their handlers.
+	 * Grade the severity of the errors of all the CPUs.
+	 */
+	for_each_possible_cpu(cpu) {
+		struct mce *mtmp = &per_cpu(mces_seen, cpu);
+
+		if (mtmp->severity > global_worst) {
+			global_worst = mtmp->severity;
+			m = &per_cpu(mces_seen, cpu);
+		}
+	}
+
+	/*
+	 * Cannot recover? Panic here then.
+	 * This dumps all the mces in the log buffer and stops the
+	 * other CPUs.
+	 */
+	if (m && global_worst >= MCE_PANIC_SEVERITY) {
+		/* call mce_severity() to get "msg" for panic */
+		mce_severity(m, NULL, &msg, true);
+		mce_panic("Fatal machine check", m, msg);
+	}
+
+	/*
+	 * For UC somewhere we let the CPU who detects it handle it.
+	 * Also must let continue the others, otherwise the handling
+	 * CPU could deadlock on a lock.
+	 */
+
+	/*
+	 * No machine check event found. Must be some external
+	 * source or one CPU is hung. Panic.
+	 */
+	if (global_worst <= MCE_KEEP_SEVERITY)
+		mce_panic("Fatal machine check from unknown source", NULL, NULL);
+
+	/*
+	 * Now clear all the mces_seen so that they don't reappear on
+	 * the next mce.
+	 */
+	for_each_possible_cpu(cpu)
+		memset(&per_cpu(mces_seen, cpu), 0, sizeof(struct mce));
+}
+
+static atomic_t global_nwo;
+
+/*
+ * Start of Monarch synchronization. This waits until all CPUs have
+ * entered the exception handler and then determines if any of them
+ * saw a fatal event that requires panic. Then it executes them
+ * in the entry order.
+ * TBD double check parallel CPU hotunplug
+ */
+static noinstr int mce_start(int *no_way_out)
+{
+	u64 timeout = (u64)mca_cfg.monarch_timeout * NSEC_PER_USEC;
+	int order, ret = -1;
+
+	if (!timeout)
+		return ret;
+
+	raw_atomic_add(*no_way_out, &global_nwo);
+	/*
+	 * Rely on the implied barrier below, such that global_nwo
+	 * is updated before mce_callin.
+	 */
+	order = raw_atomic_inc_return(&mce_callin);
+	arch_cpumask_clear_cpu(smp_processor_id(), &mce_missing_cpus);
+
+	/* Enable instrumentation around calls to external facilities */
+	instrumentation_begin();
+
+	/*
+	 * Wait for everyone.
+	 */
+	while (raw_atomic_read(&mce_callin) != num_online_cpus()) {
+		if (mce_timed_out(&timeout,
+				  "Timeout: Not all CPUs entered broadcast exception handler")) {
+			raw_atomic_set(&global_nwo, 0);
+			goto out;
+		}
+		ndelay(SPINUNIT);
+	}
+
+	/*
+	 * mce_callin should be read before global_nwo
+	 */
+	smp_rmb();
+
+	if (order == 1) {
+		/*
+		 * Monarch: Starts executing now, the others wait.
+		 */
+		raw_atomic_set(&mce_executing, 1);
+	} else {
+		/*
+		 * Subject: Now start the scanning loop one by one in
+		 * the original callin order.
+		 * This way when there are any shared banks it will be
+		 * only seen by one CPU before cleared, avoiding duplicates.
+		 */
+		while (raw_atomic_read(&mce_executing) < order) {
+			if (mce_timed_out(&timeout,
+					  "Timeout: Subject CPUs unable to finish machine check processing")) {
+				raw_atomic_set(&global_nwo, 0);
+				goto out;
+			}
+			ndelay(SPINUNIT);
+		}
+	}
+
+	/*
+	 * Cache the global no_way_out state.
+	 */
+	*no_way_out = raw_atomic_read(&global_nwo);
+
+	ret = order;
+
+out:
+	instrumentation_end();
+
+	return ret;
+}
+
+/*
+ * Synchronize between CPUs after main scanning loop.
+ * This invokes the bulk of the Monarch processing.
+ */
+static noinstr int mce_end(int order)
+{
+	u64 timeout = (u64)mca_cfg.monarch_timeout * NSEC_PER_USEC;
+	int ret = -1;
+
+	/* Allow instrumentation around external facilities. */
+	instrumentation_begin();
+
+	if (!timeout)
+		goto reset;
+	if (order < 0)
+		goto reset;
+
+	/*
+	 * Allow others to run.
+	 */
+	atomic_inc(&mce_executing);
+
+	if (order == 1) {
+		/*
+		 * Monarch: Wait for everyone to go through their scanning
+		 * loops.
+		 */
+		while (atomic_read(&mce_executing) <= num_online_cpus()) {
+			if (mce_timed_out(&timeout,
+					  "Timeout: Monarch CPU unable to finish machine check processing"))
+				goto reset;
+			ndelay(SPINUNIT);
+		}
+
+		mce_reign();
+		barrier();
+		ret = 0;
+	} else {
+		/*
+		 * Subject: Wait for Monarch to finish.
+		 */
+		while (atomic_read(&mce_executing) != 0) {
+			if (mce_timed_out(&timeout,
+					  "Timeout: Monarch CPU did not finish machine check processing"))
+				goto reset;
+			ndelay(SPINUNIT);
+		}
+
+		/*
+		 * Don't reset anything. That's done by the Monarch.
+		 */
+		ret = 0;
+		goto out;
+	}
+
+	/*
+	 * Reset all global state.
+	 */
+reset:
+	atomic_set(&global_nwo, 0);
+	atomic_set(&mce_callin, 0);
+	cpumask_setall(&mce_missing_cpus);
+	barrier();
+
+	/*
+	 * Let others run again.
+	 */
+	atomic_set(&mce_executing, 0);
+
+out:
+	instrumentation_end();
+
+	return ret;
+}
+
+static __always_inline void mce_clear_state(unsigned long *toclear)
+{
+	int i;
+
+	for (i = 0; i < this_cpu_read(mce_num_banks); i++) {
+		if (arch_test_bit(i, toclear))
+			mce_wrmsrl(mca_msr_reg(i, MCA_STATUS), 0);
+	}
+}
+
+/*
+ * Cases where we avoid rendezvous handler timeout:
+ * 1) If this CPU is offline.
+ *
+ * 2) If crashing_cpu was set, e.g. we're entering kdump and we need to
+ *  skip those CPUs which remain looping in the 1st kernel - see
+ *  crash_nmi_callback().
+ *
+ * Note: there still is a small window between kexec-ing and the new,
+ * kdump kernel establishing a new #MC handler where a broadcasted MCE
+ * might not get handled properly.
+ */
+static noinstr bool mce_check_crashing_cpu(void)
+{
+	unsigned int cpu = smp_processor_id();
+
+	if (arch_cpu_is_offline(cpu) ||
+	    (crashing_cpu != -1 && crashing_cpu != cpu)) {
+		u64 mcgstatus;
+
+		mcgstatus = __rdmsr(MSR_IA32_MCG_STATUS);
+
+		if (boot_cpu_data.x86_vendor == X86_VENDOR_ZHAOXIN) {
+			if (mcgstatus & MCG_STATUS_LMCES)
+				return false;
+		}
+
+		if (mcgstatus & MCG_STATUS_RIPV) {
+			__wrmsr(MSR_IA32_MCG_STATUS, 0, 0);
+			return true;
+		}
+	}
+	return false;
+}
+
+static __always_inline int
+__mc_scan_banks(struct mce *m, struct pt_regs *regs, struct mce *final,
+		unsigned long *toclear, unsigned long *valid_banks, int no_way_out,
+		int *worst)
+{
+	struct mce_bank *mce_banks = this_cpu_ptr(mce_banks_array);
+	struct mca_config *cfg = &mca_cfg;
+	int severity, i, taint = 0;
+
+	for (i = 0; i < this_cpu_read(mce_num_banks); i++) {
+		arch___clear_bit(i, toclear);
+		if (!arch_test_bit(i, valid_banks))
+			continue;
+
+		if (!mce_banks[i].ctl)
+			continue;
+
+		m->misc = 0;
+		m->addr = 0;
+		m->bank = i;
+
+		m->status = mce_rdmsrl(mca_msr_reg(i, MCA_STATUS));
+		if (!(m->status & MCI_STATUS_VAL))
+			continue;
+
+		/*
+		 * Corrected or non-signaled errors are handled by
+		 * machine_check_poll(). Leave them alone, unless this panics.
+		 */
+		if (!(m->status & (cfg->ser ? MCI_STATUS_S : MCI_STATUS_UC)) &&
+			!no_way_out)
+			continue;
+
+		/* Set taint even when machine check was not enabled. */
+		taint++;
+
+		severity = mce_severity(m, regs, NULL, true);
+
+		/*
+		 * When machine check was for corrected/deferred handler don't
+		 * touch, unless we're panicking.
+		 */
+		if ((severity == MCE_KEEP_SEVERITY ||
+		     severity == MCE_UCNA_SEVERITY) && !no_way_out)
+			continue;
+
+		arch___set_bit(i, toclear);
+
+		/* Machine check event was not enabled. Clear, but ignore. */
+		if (severity == MCE_NO_SEVERITY)
+			continue;
+
+		mce_read_aux(m, i);
+
+		/* assuming valid severity level != 0 */
+		m->severity = severity;
+
+		/*
+		 * Enable instrumentation around the mce_log() call which is
+		 * done in #MC context, where instrumentation is disabled.
+		 */
+		instrumentation_begin();
+		mce_log(m);
+		instrumentation_end();
+
+		if (severity > *worst) {
+			*final = *m;
+			*worst = severity;
+		}
+	}
+
+	/* mce_clear_state will clear *final, save locally for use later */
+	*m = *final;
+
+	return taint;
+}
+
+static void kill_me_now(struct callback_head *ch)
+{
+	struct task_struct *p = container_of(ch, struct task_struct, mce_kill_me);
+
+	p->mce_count = 0;
+	force_sig(SIGBUS);
+}
+
+static void kill_me_maybe(struct callback_head *cb)
+{
+	struct task_struct *p = container_of(cb, struct task_struct, mce_kill_me);
+	int flags = MF_ACTION_REQUIRED;
+	unsigned long pfn;
+	int ret;
+
+	p->mce_count = 0;
+	pr_err("Uncorrected hardware memory error in user-access at %llx", p->mce_addr);
+
+	if (!p->mce_ripv)
+		flags |= MF_MUST_KILL;
+
+	pfn = (p->mce_addr & MCI_ADDR_PHYSADDR) >> PAGE_SHIFT;
+	ret = memory_failure(pfn, flags);
+	if (!ret) {
+		set_mce_nospec(pfn);
+		sync_core();
+		return;
+	}
+
+	/*
+	 * -EHWPOISON from memory_failure() means that it already sent SIGBUS
+	 * to the current process with the proper error info,
+	 * -EOPNOTSUPP means hwpoison_filter() filtered the error event,
+	 *
+	 * In both cases, no further processing is required.
+	 */
+	if (ret == -EHWPOISON || ret == -EOPNOTSUPP)
+		return;
+
+	pr_err("Memory error not recovered");
+	kill_me_now(cb);
+}
+
+static void kill_me_never(struct callback_head *cb)
+{
+	struct task_struct *p = container_of(cb, struct task_struct, mce_kill_me);
+	unsigned long pfn;
+
+	p->mce_count = 0;
+	pr_err("Kernel accessed poison in user space at %llx\n", p->mce_addr);
+	pfn = (p->mce_addr & MCI_ADDR_PHYSADDR) >> PAGE_SHIFT;
+	if (!memory_failure(pfn, 0))
+		set_mce_nospec(pfn);
+}
+
+static void queue_task_work(struct mce *m, char *msg, void (*func)(struct callback_head *))
+{
+	int count = ++current->mce_count;
+
+	/* First call, save all the details */
+	if (count == 1) {
+		current->mce_addr = m->addr;
+		current->mce_kflags = m->kflags;
+		current->mce_ripv = !!(m->mcgstatus & MCG_STATUS_RIPV);
+		current->mce_whole_page = whole_page(m);
+		current->mce_kill_me.func = func;
+	}
+
+	/* Ten is likely overkill. Don't expect more than two faults before task_work() */
+	if (count > 10)
+		mce_panic("Too many consecutive machine checks while accessing user data", m, msg);
+
+	/* Second or later call, make sure page address matches the one from first call */
+	if (count > 1 && (current->mce_addr >> PAGE_SHIFT) != (m->addr >> PAGE_SHIFT))
+		mce_panic("Consecutive machine checks to different user pages", m, msg);
+
+	/* Do not call task_work_add() more than once */
+	if (count > 1)
+		return;
+
+	task_work_add(current, &current->mce_kill_me, TWA_RESUME);
+}
+
+/* Handle unconfigured int18 (should never happen) */
+static noinstr void unexpected_machine_check(struct pt_regs *regs)
+{
+	instrumentation_begin();
+	pr_err("CPU#%d: Unexpected int18 (Machine Check)\n",
+	       smp_processor_id());
+	instrumentation_end();
+}
+
+/*
+ * The actual machine check handler. This only handles real exceptions when
+ * something got corrupted coming in through int 18.
+ *
+ * This is executed in #MC context not subject to normal locking rules.
+ * This implies that most kernel services cannot be safely used. Don't even
+ * think about putting a printk in there!
+ *
+ * On Intel systems this is entered on all CPUs in parallel through
+ * MCE broadcast. However some CPUs might be broken beyond repair,
+ * so be always careful when synchronizing with others.
+ *
+ * Tracing and kprobes are disabled: if we interrupted a kernel context
+ * with IF=1, we need to minimize stack usage.  There are also recursion
+ * issues: if the machine check was due to a failure of the memory
+ * backing the user stack, tracing that reads the user stack will cause
+ * potentially infinite recursion.
+ *
+ * Currently, the #MC handler calls out to a number of external facilities
+ * and, therefore, allows instrumentation around them. The optimal thing to
+ * have would be to do the absolutely minimal work required in #MC context
+ * and have instrumentation disabled only around that. Further processing can
+ * then happen in process context where instrumentation is allowed. Achieving
+ * that requires careful auditing and modifications. Until then, the code
+ * allows instrumentation temporarily, where required. *
+ */
+noinstr void do_machine_check(struct pt_regs *regs)
+{
+	int worst = 0, order, no_way_out, kill_current_task, lmce, taint = 0;
+	DECLARE_BITMAP(valid_banks, MAX_NR_BANKS) = { 0 };
+	DECLARE_BITMAP(toclear, MAX_NR_BANKS) = { 0 };
+	struct mce m, *final;
+	char *msg = NULL;
+
+	if (unlikely(mce_flags.p5))
+		return pentium_machine_check(regs);
+	else if (unlikely(mce_flags.winchip))
+		return winchip_machine_check(regs);
+	else if (unlikely(!mca_cfg.initialized))
+		return unexpected_machine_check(regs);
+
+	if (mce_flags.skx_repmov_quirk && quirk_skylake_repmov())
+		goto clear;
+
+	/*
+	 * Establish sequential order between the CPUs entering the machine
+	 * check handler.
+	 */
+	order = -1;
+
+	/*
+	 * If no_way_out gets set, there is no safe way to recover from this
+	 * MCE.
+	 */
+	no_way_out = 0;
+
+	/*
+	 * If kill_current_task is not set, there might be a way to recover from this
+	 * error.
+	 */
+	kill_current_task = 0;
+
+	/*
+	 * MCEs are always local on AMD. Same is determined by MCG_STATUS_LMCES
+	 * on Intel.
+	 */
+	lmce = 1;
+
+	this_cpu_inc(mce_exception_count);
+
+	mce_gather_info(&m, regs);
+	m.tsc = rdtsc();
+
+	final = this_cpu_ptr(&mces_seen);
+	*final = m;
+
+	no_way_out = mce_no_way_out(&m, &msg, valid_banks, regs);
+
+	barrier();
+
+	/*
+	 * When no restart IP might need to kill or panic.
+	 * Assume the worst for now, but if we find the
+	 * severity is MCE_AR_SEVERITY we have other options.
+	 */
+	if (!(m.mcgstatus & MCG_STATUS_RIPV))
+		kill_current_task = 1;
+	/*
+	 * Check if this MCE is signaled to only this logical processor,
+	 * on Intel, Zhaoxin only.
+	 */
+	if (m.cpuvendor == X86_VENDOR_INTEL ||
+	    m.cpuvendor == X86_VENDOR_ZHAOXIN)
+		lmce = m.mcgstatus & MCG_STATUS_LMCES;
+
+	/*
+	 * Local machine check may already know that we have to panic.
+	 * Broadcast machine check begins rendezvous in mce_start()
+	 * Go through all banks in exclusion of the other CPUs. This way we
+	 * don't report duplicated events on shared banks because the first one
+	 * to see it will clear it.
+	 */
+	if (lmce) {
+		if (no_way_out)
+			mce_panic("Fatal local machine check", &m, msg);
+	} else {
+		order = mce_start(&no_way_out);
+	}
+
+	taint = __mc_scan_banks(&m, regs, final, toclear, valid_banks, no_way_out, &worst);
+
+	if (!no_way_out)
+		mce_clear_state(toclear);
+
+	/*
+	 * Do most of the synchronization with other CPUs.
+	 * When there's any problem use only local no_way_out state.
+	 */
+	if (!lmce) {
+		if (mce_end(order) < 0) {
+			if (!no_way_out)
+				no_way_out = worst >= MCE_PANIC_SEVERITY;
+
+			if (no_way_out)
+				mce_panic("Fatal machine check on current CPU", &m, msg);
+		}
+	} else {
+		/*
+		 * If there was a fatal machine check we should have
+		 * already called mce_panic earlier in this function.
+		 * Since we re-read the banks, we might have found
+		 * something new. Check again to see if we found a
+		 * fatal error. We call "mce_severity()" again to
+		 * make sure we have the right "msg".
+		 */
+		if (worst >= MCE_PANIC_SEVERITY) {
+			mce_severity(&m, regs, &msg, true);
+			mce_panic("Local fatal machine check!", &m, msg);
+		}
+	}
+
+	/*
+	 * Enable instrumentation around the external facilities like task_work_add()
+	 * (via queue_task_work()), fixup_exception() etc. For now, that is. Fixing this
+	 * properly would need a lot more involved reorganization.
+	 */
+	instrumentation_begin();
+
+	if (taint)
+		add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE);
+
+	if (worst != MCE_AR_SEVERITY && !kill_current_task)
+		goto out;
+
+	/* Fault was in user mode and we need to take some action */
+	if ((m.cs & 3) == 3) {
+		/* If this triggers there is no way to recover. Die hard. */
+		BUG_ON(!on_thread_stack() || !user_mode(regs));
+
+		if (!mce_usable_address(&m))
+			queue_task_work(&m, msg, kill_me_now);
+		else
+			queue_task_work(&m, msg, kill_me_maybe);
+
+	} else {
+		/*
+		 * Handle an MCE which has happened in kernel space but from
+		 * which the kernel can recover: ex_has_fault_handler() has
+		 * already verified that the rIP at which the error happened is
+		 * a rIP from which the kernel can recover (by jumping to
+		 * recovery code specified in _ASM_EXTABLE_FAULT()) and the
+		 * corresponding exception handler which would do that is the
+		 * proper one.
+		 */
+		if (m.kflags & MCE_IN_KERNEL_RECOV) {
+			if (!fixup_exception(regs, X86_TRAP_MC, 0, 0))
+				mce_panic("Failed kernel mode recovery", &m, msg);
+		}
+
+		if (m.kflags & MCE_IN_KERNEL_COPYIN)
+			queue_task_work(&m, msg, kill_me_never);
+	}
+
+out:
+	instrumentation_end();
+
+clear:
+	mce_wrmsrl(MSR_IA32_MCG_STATUS, 0);
+}
+EXPORT_SYMBOL_GPL(do_machine_check);
+
+#ifndef CONFIG_MEMORY_FAILURE
+int memory_failure(unsigned long pfn, int flags)
+{
+	/* mce_severity() should not hand us an ACTION_REQUIRED error */
+	BUG_ON(flags & MF_ACTION_REQUIRED);
+	pr_err("Uncorrected memory error in page 0x%lx ignored\n"
+	       "Rebuild kernel with CONFIG_MEMORY_FAILURE=y for smarter handling\n",
+	       pfn);
+
+	return 0;
+}
+#endif
+
+/*
+ * Periodic polling timer for "silent" machine check errors.  If the
+ * poller finds an MCE, poll 2x faster.  When the poller finds no more
+ * errors, poll 2x slower (up to check_interval seconds).
+ */
+static unsigned long check_interval = INITIAL_CHECK_INTERVAL;
+
+static DEFINE_PER_CPU(unsigned long, mce_next_interval); /* in jiffies */
+static DEFINE_PER_CPU(struct timer_list, mce_timer);
+
+static unsigned long mce_adjust_timer_default(unsigned long interval)
+{
+	return interval;
+}
+
+static unsigned long (*mce_adjust_timer)(unsigned long interval) = mce_adjust_timer_default;
+
+static void __start_timer(struct timer_list *t, unsigned long interval)
+{
+	unsigned long when = jiffies + interval;
+	unsigned long flags;
+
+	local_irq_save(flags);
+
+	if (!timer_pending(t) || time_before(when, t->expires))
+		mod_timer(t, round_jiffies(when));
+
+	local_irq_restore(flags);
+}
+
+static void mc_poll_banks_default(void)
+{
+	machine_check_poll(0, this_cpu_ptr(&mce_poll_banks));
+}
+
+void (*mc_poll_banks)(void) = mc_poll_banks_default;
+
+static void mce_timer_fn(struct timer_list *t)
+{
+	struct timer_list *cpu_t = this_cpu_ptr(&mce_timer);
+	unsigned long iv;
+
+	WARN_ON(cpu_t != t);
+
+	iv = __this_cpu_read(mce_next_interval);
+
+	if (mce_available(this_cpu_ptr(&cpu_info))) {
+		mc_poll_banks();
+
+		if (mce_intel_cmci_poll()) {
+			iv = mce_adjust_timer(iv);
+			goto done;
+		}
+	}
+
+	/*
+	 * Alert userspace if needed. If we logged an MCE, reduce the polling
+	 * interval, otherwise increase the polling interval.
+	 */
+	if (mce_notify_irq())
+		iv = max(iv / 2, (unsigned long) HZ/100);
+	else
+		iv = min(iv * 2, round_jiffies_relative(check_interval * HZ));
+
+done:
+	__this_cpu_write(mce_next_interval, iv);
+	__start_timer(t, iv);
+}
+
+/*
+ * Ensure that the timer is firing in @interval from now.
+ */
+void mce_timer_kick(unsigned long interval)
+{
+	struct timer_list *t = this_cpu_ptr(&mce_timer);
+	unsigned long iv = __this_cpu_read(mce_next_interval);
+
+	__start_timer(t, interval);
+
+	if (interval < iv)
+		__this_cpu_write(mce_next_interval, interval);
+}
+
+/* Must not be called in IRQ context where del_timer_sync() can deadlock */
+static void mce_timer_delete_all(void)
+{
+	int cpu;
+
+	for_each_online_cpu(cpu)
+		del_timer_sync(&per_cpu(mce_timer, cpu));
+}
+
+/*
+ * Notify the user(s) about new machine check events.
+ * Can be called from interrupt context, but not from machine check/NMI
+ * context.
+ */
+int mce_notify_irq(void)
+{
+	/* Not more than two messages every minute */
+	static DEFINE_RATELIMIT_STATE(ratelimit, 60*HZ, 2);
+
+	if (test_and_clear_bit(0, &mce_need_notify)) {
+		mce_work_trigger();
+
+		if (__ratelimit(&ratelimit))
+			pr_info(HW_ERR "Machine check events logged\n");
+
+		return 1;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mce_notify_irq);
+
+static void __mcheck_cpu_mce_banks_init(void)
+{
+	struct mce_bank *mce_banks = this_cpu_ptr(mce_banks_array);
+	u8 n_banks = this_cpu_read(mce_num_banks);
+	int i;
+
+	for (i = 0; i < n_banks; i++) {
+		struct mce_bank *b = &mce_banks[i];
+
+		/*
+		 * Init them all, __mcheck_cpu_apply_quirks() is going to apply
+		 * the required vendor quirks before
+		 * __mcheck_cpu_init_clear_banks() does the final bank setup.
+		 */
+		b->ctl = -1ULL;
+		b->init = true;
+	}
+}
+
+/*
+ * Initialize Machine Checks for a CPU.
+ */
+static void __mcheck_cpu_cap_init(void)
+{
+	u64 cap;
+	u8 b;
+
+	rdmsrl(MSR_IA32_MCG_CAP, cap);
+
+	b = cap & MCG_BANKCNT_MASK;
+
+	if (b > MAX_NR_BANKS) {
+		pr_warn("CPU%d: Using only %u machine check banks out of %u\n",
+			smp_processor_id(), MAX_NR_BANKS, b);
+		b = MAX_NR_BANKS;
+	}
+
+	this_cpu_write(mce_num_banks, b);
+
+	__mcheck_cpu_mce_banks_init();
+
+	/* Use accurate RIP reporting if available. */
+	if ((cap & MCG_EXT_P) && MCG_EXT_CNT(cap) >= 9)
+		mca_cfg.rip_msr = MSR_IA32_MCG_EIP;
+
+	if (cap & MCG_SER_P)
+		mca_cfg.ser = 1;
+}
+
+static void __mcheck_cpu_init_generic(void)
+{
+	enum mcp_flags m_fl = 0;
+	mce_banks_t all_banks;
+	u64 cap;
+
+	if (!mca_cfg.bootlog)
+		m_fl = MCP_DONTLOG;
+
+	/*
+	 * Log the machine checks left over from the previous reset. Log them
+	 * only, do not start processing them. That will happen in mcheck_late_init()
+	 * when all consumers have been registered on the notifier chain.
+	 */
+	bitmap_fill(all_banks, MAX_NR_BANKS);
+	machine_check_poll(MCP_UC | MCP_QUEUE_LOG | m_fl, &all_banks);
+
+	cr4_set_bits(X86_CR4_MCE);
+
+	rdmsrl(MSR_IA32_MCG_CAP, cap);
+	if (cap & MCG_CTL_P)
+		wrmsr(MSR_IA32_MCG_CTL, 0xffffffff, 0xffffffff);
+}
+
+static void __mcheck_cpu_init_clear_banks(void)
+{
+	struct mce_bank *mce_banks = this_cpu_ptr(mce_banks_array);
+	int i;
+
+	for (i = 0; i < this_cpu_read(mce_num_banks); i++) {
+		struct mce_bank *b = &mce_banks[i];
+
+		if (!b->init)
+			continue;
+		wrmsrl(mca_msr_reg(i, MCA_CTL), b->ctl);
+		wrmsrl(mca_msr_reg(i, MCA_STATUS), 0);
+	}
+}
+
+/*
+ * Do a final check to see if there are any unused/RAZ banks.
+ *
+ * This must be done after the banks have been initialized and any quirks have
+ * been applied.
+ *
+ * Do not call this from any user-initiated flows, e.g. CPU hotplug or sysfs.
+ * Otherwise, a user who disables a bank will not be able to re-enable it
+ * without a system reboot.
+ */
+static void __mcheck_cpu_check_banks(void)
+{
+	struct mce_bank *mce_banks = this_cpu_ptr(mce_banks_array);
+	u64 msrval;
+	int i;
+
+	for (i = 0; i < this_cpu_read(mce_num_banks); i++) {
+		struct mce_bank *b = &mce_banks[i];
+
+		if (!b->init)
+			continue;
+
+		rdmsrl(mca_msr_reg(i, MCA_CTL), msrval);
+		b->init = !!msrval;
+	}
+}
+
+/* Add per CPU specific workarounds here */
+static int __mcheck_cpu_apply_quirks(struct cpuinfo_x86 *c)
+{
+	struct mce_bank *mce_banks = this_cpu_ptr(mce_banks_array);
+	struct mca_config *cfg = &mca_cfg;
+
+	if (c->x86_vendor == X86_VENDOR_UNKNOWN) {
+		pr_info("unknown CPU type - not enabling MCE support\n");
+		return -EOPNOTSUPP;
+	}
+
+	/* This should be disabled by the BIOS, but isn't always */
+	if (c->x86_vendor == X86_VENDOR_AMD) {
+		if (c->x86 == 15 && this_cpu_read(mce_num_banks) > 4) {
+			/*
+			 * disable GART TBL walk error reporting, which
+			 * trips off incorrectly with the IOMMU & 3ware
+			 * & Cerberus:
+			 */
+			clear_bit(10, (unsigned long *)&mce_banks[4].ctl);
+		}
+		if (c->x86 < 0x11 && cfg->bootlog < 0) {
+			/*
+			 * Lots of broken BIOS around that don't clear them
+			 * by default and leave crap in there. Don't log:
+			 */
+			cfg->bootlog = 0;
+		}
+		/*
+		 * Various K7s with broken bank 0 around. Always disable
+		 * by default.
+		 */
+		if (c->x86 == 6 && this_cpu_read(mce_num_banks) > 0)
+			mce_banks[0].ctl = 0;
+
+		/*
+		 * overflow_recov is supported for F15h Models 00h-0fh
+		 * even though we don't have a CPUID bit for it.
+		 */
+		if (c->x86 == 0x15 && c->x86_model <= 0xf)
+			mce_flags.overflow_recov = 1;
+
+		if (c->x86 >= 0x17 && c->x86 <= 0x1A)
+			mce_flags.zen_ifu_quirk = 1;
+
+	}
+
+	if (c->x86_vendor == X86_VENDOR_INTEL) {
+		/*
+		 * SDM documents that on family 6 bank 0 should not be written
+		 * because it aliases to another special BIOS controlled
+		 * register.
+		 * But it's not aliased anymore on model 0x1a+
+		 * Don't ignore bank 0 completely because there could be a
+		 * valid event later, merely don't write CTL0.
+		 */
+
+		if (c->x86 == 6 && c->x86_model < 0x1A && this_cpu_read(mce_num_banks) > 0)
+			mce_banks[0].init = false;
+
+		/*
+		 * All newer Intel systems support MCE broadcasting. Enable
+		 * synchronization with a one second timeout.
+		 */
+		if ((c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xe)) &&
+			cfg->monarch_timeout < 0)
+			cfg->monarch_timeout = USEC_PER_SEC;
+
+		/*
+		 * There are also broken BIOSes on some Pentium M and
+		 * earlier systems:
+		 */
+		if (c->x86 == 6 && c->x86_model <= 13 && cfg->bootlog < 0)
+			cfg->bootlog = 0;
+
+		if (c->x86 == 6 && c->x86_model == 45)
+			mce_flags.snb_ifu_quirk = 1;
+
+		/*
+		 * Skylake, Cascacde Lake and Cooper Lake require a quirk on
+		 * rep movs.
+		 */
+		if (c->x86 == 6 && c->x86_model == INTEL_FAM6_SKYLAKE_X)
+			mce_flags.skx_repmov_quirk = 1;
+	}
+
+	if (c->x86_vendor == X86_VENDOR_ZHAOXIN) {
+		/*
+		 * All newer Zhaoxin CPUs support MCE broadcasting. Enable
+		 * synchronization with a one second timeout.
+		 */
+		if (c->x86 > 6 || (c->x86_model == 0x19 || c->x86_model == 0x1f)) {
+			if (cfg->monarch_timeout < 0)
+				cfg->monarch_timeout = USEC_PER_SEC;
+		}
+	}
+
+	if (cfg->monarch_timeout < 0)
+		cfg->monarch_timeout = 0;
+	if (cfg->bootlog != 0)
+		cfg->panic_timeout = 30;
+
+	return 0;
+}
+
+static int __mcheck_cpu_ancient_init(struct cpuinfo_x86 *c)
+{
+	if (c->x86 != 5)
+		return 0;
+
+	switch (c->x86_vendor) {
+	case X86_VENDOR_INTEL:
+		intel_p5_mcheck_init(c);
+		mce_flags.p5 = 1;
+		return 1;
+	case X86_VENDOR_CENTAUR:
+		winchip_mcheck_init(c);
+		mce_flags.winchip = 1;
+		return 1;
+	default:
+		return 0;
+	}
+
+	return 0;
+}
+
+/*
+ * Init basic CPU features needed for early decoding of MCEs.
+ */
+static void __mcheck_cpu_init_early(struct cpuinfo_x86 *c)
+{
+	if (c->x86_vendor == X86_VENDOR_AMD || c->x86_vendor == X86_VENDOR_HYGON) {
+		mce_flags.overflow_recov = !!cpu_has(c, X86_FEATURE_OVERFLOW_RECOV);
+		mce_flags.succor	 = !!cpu_has(c, X86_FEATURE_SUCCOR);
+		mce_flags.smca		 = !!cpu_has(c, X86_FEATURE_SMCA);
+		mce_flags.amd_threshold	 = 1;
+	}
+}
+
+static void mce_centaur_feature_init(struct cpuinfo_x86 *c)
+{
+	struct mca_config *cfg = &mca_cfg;
+
+	 /*
+	  * All newer Centaur CPUs support MCE broadcasting. Enable
+	  * synchronization with a one second timeout.
+	  */
+	if ((c->x86 == 6 && c->x86_model == 0xf && c->x86_stepping >= 0xe) ||
+	     c->x86 > 6) {
+		if (cfg->monarch_timeout < 0)
+			cfg->monarch_timeout = USEC_PER_SEC;
+	}
+}
+
+static void mce_zhaoxin_feature_init(struct cpuinfo_x86 *c)
+{
+	struct mce_bank *mce_banks = this_cpu_ptr(mce_banks_array);
+
+	/*
+	 * These CPUs have MCA bank 8 which reports only one error type called
+	 * SVAD (System View Address Decoder). The reporting of that error is
+	 * controlled by IA32_MC8.CTL.0.
+	 *
+	 * If enabled, prefetching on these CPUs will cause SVAD MCE when
+	 * virtual machines start and result in a system  panic. Always disable
+	 * bank 8 SVAD error by default.
+	 */
+	if ((c->x86 == 7 && c->x86_model == 0x1b) ||
+	    (c->x86_model == 0x19 || c->x86_model == 0x1f)) {
+		if (this_cpu_read(mce_num_banks) > 8)
+			mce_banks[8].ctl = 0;
+	}
+
+	intel_init_cmci();
+	intel_init_lmce();
+	mce_adjust_timer = cmci_intel_adjust_timer;
+}
+
+static void mce_zhaoxin_feature_clear(struct cpuinfo_x86 *c)
+{
+	intel_clear_lmce();
+}
+
+static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
+{
+	switch (c->x86_vendor) {
+	case X86_VENDOR_INTEL:
+		mce_intel_feature_init(c);
+		mce_adjust_timer = cmci_intel_adjust_timer;
+		break;
+
+	case X86_VENDOR_AMD: {
+		mce_amd_feature_init(c);
+		break;
+		}
+
+	case X86_VENDOR_HYGON:
+		mce_hygon_feature_init(c);
+		break;
+
+	case X86_VENDOR_CENTAUR:
+		mce_centaur_feature_init(c);
+		break;
+
+	case X86_VENDOR_ZHAOXIN:
+		mce_zhaoxin_feature_init(c);
+		break;
+
+	default:
+		break;
+	}
+}
+
+static void __mcheck_cpu_clear_vendor(struct cpuinfo_x86 *c)
+{
+	switch (c->x86_vendor) {
+	case X86_VENDOR_INTEL:
+		mce_intel_feature_clear(c);
+		break;
+
+	case X86_VENDOR_ZHAOXIN:
+		mce_zhaoxin_feature_clear(c);
+		break;
+
+	default:
+		break;
+	}
+}
+
+static void mce_start_timer(struct timer_list *t)
+{
+	unsigned long iv = check_interval * HZ;
+
+	if (mca_cfg.ignore_ce || !iv)
+		return;
+
+	this_cpu_write(mce_next_interval, iv);
+	__start_timer(t, iv);
+}
+
+static void __mcheck_cpu_setup_timer(void)
+{
+	struct timer_list *t = this_cpu_ptr(&mce_timer);
+
+	timer_setup(t, mce_timer_fn, TIMER_PINNED);
+}
+
+static void __mcheck_cpu_init_timer(void)
+{
+	struct timer_list *t = this_cpu_ptr(&mce_timer);
+
+	timer_setup(t, mce_timer_fn, TIMER_PINNED);
+	mce_start_timer(t);
+}
+
+bool filter_mce(struct mce *m)
+{
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+		return amd_filter_mce(m);
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
+		return intel_filter_mce(m);
+
+	return false;
+}
+
+static __always_inline void exc_machine_check_kernel(struct pt_regs *regs)
+{
+	irqentry_state_t irq_state;
+
+	WARN_ON_ONCE(user_mode(regs));
+
+	/*
+	 * Only required when from kernel mode. See
+	 * mce_check_crashing_cpu() for details.
+	 */
+	if (mca_cfg.initialized && mce_check_crashing_cpu())
+		return;
+
+	irq_state = irqentry_nmi_enter(regs);
+
+	do_machine_check(regs);
+
+	irqentry_nmi_exit(regs, irq_state);
+}
+
+static __always_inline void exc_machine_check_user(struct pt_regs *regs)
+{
+	irqentry_enter_from_user_mode(regs);
+
+	do_machine_check(regs);
+
+	irqentry_exit_to_user_mode(regs);
+}
+
+#ifdef CONFIG_X86_64
+/* MCE hit kernel mode */
+DEFINE_IDTENTRY_MCE(exc_machine_check)
+{
+	unsigned long dr7;
+
+	dr7 = local_db_save();
+	exc_machine_check_kernel(regs);
+	local_db_restore(dr7);
+}
+
+/* The user mode variant. */
+DEFINE_IDTENTRY_MCE_USER(exc_machine_check)
+{
+	unsigned long dr7;
+
+	dr7 = local_db_save();
+	exc_machine_check_user(regs);
+	local_db_restore(dr7);
+}
+#else
+/* 32bit unified entry point */
+DEFINE_IDTENTRY_RAW(exc_machine_check)
+{
+	unsigned long dr7;
+
+	dr7 = local_db_save();
+	if (user_mode(regs))
+		exc_machine_check_user(regs);
+	else
+		exc_machine_check_kernel(regs);
+	local_db_restore(dr7);
+}
+#endif
+
+/*
+ * Called for each booted CPU to set up machine checks.
+ * Must be called with preempt off:
+ */
+void mcheck_cpu_init(struct cpuinfo_x86 *c)
+{
+	if (mca_cfg.disabled)
+		return;
+
+	if (__mcheck_cpu_ancient_init(c))
+		return;
+
+	if (!mce_available(c))
+		return;
+
+	__mcheck_cpu_cap_init();
+
+	if (__mcheck_cpu_apply_quirks(c) < 0) {
+		mca_cfg.disabled = 1;
+		return;
+	}
+
+	if (mce_gen_pool_init()) {
+		mca_cfg.disabled = 1;
+		pr_emerg("Couldn't allocate MCE records pool!\n");
+		return;
+	}
+
+	mca_cfg.initialized = 1;
+
+	__mcheck_cpu_init_early(c);
+	__mcheck_cpu_init_generic();
+	__mcheck_cpu_init_vendor(c);
+	__mcheck_cpu_init_clear_banks();
+	__mcheck_cpu_check_banks();
+	__mcheck_cpu_setup_timer();
+}
+
+/*
+ * Called for each booted CPU to clear some machine checks opt-ins
+ */
+void mcheck_cpu_clear(struct cpuinfo_x86 *c)
+{
+	if (mca_cfg.disabled)
+		return;
+
+	if (!mce_available(c))
+		return;
+
+	/*
+	 * Possibly to clear general settings generic to x86
+	 * __mcheck_cpu_clear_generic(c);
+	 */
+	__mcheck_cpu_clear_vendor(c);
+
+}
+
+static void __mce_disable_bank(void *arg)
+{
+	int bank = *((int *)arg);
+	__clear_bit(bank, this_cpu_ptr(mce_poll_banks));
+	cmci_disable_bank(bank);
+}
+
+void mce_disable_bank(int bank)
+{
+	if (bank >= this_cpu_read(mce_num_banks)) {
+		pr_warn(FW_BUG
+			"Ignoring request to disable invalid MCA bank %d.\n",
+			bank);
+		return;
+	}
+	set_bit(bank, mce_banks_ce_disabled);
+	on_each_cpu(__mce_disable_bank, &bank, 1);
+}
+
+/*
+ * mce=off Disables machine check
+ * mce=no_cmci Disables CMCI
+ * mce=no_lmce Disables LMCE
+ * mce=dont_log_ce Clears corrected events silently, no log created for CEs.
+ * mce=print_all Print all machine check logs to console
+ * mce=ignore_ce Disables polling and CMCI, corrected events are not cleared.
+ * mce=TOLERANCELEVEL[,monarchtimeout] (number, see above)
+ *	monarchtimeout is how long to wait for other CPUs on machine
+ *	check, or 0 to not wait
+ * mce=bootlog Log MCEs from before booting. Disabled by default on AMD Fam10h
+	and older.
+ * mce=nobootlog Don't log MCEs from before booting.
+ * mce=bios_cmci_threshold Don't program the CMCI threshold
+ * mce=recovery force enable copy_mc_fragile()
+ */
+static int __init mcheck_enable(char *str)
+{
+	struct mca_config *cfg = &mca_cfg;
+
+	if (*str == 0) {
+		enable_p5_mce();
+		return 1;
+	}
+	if (*str == '=')
+		str++;
+	if (!strcmp(str, "off"))
+		cfg->disabled = 1;
+	else if (!strcmp(str, "no_cmci"))
+		cfg->cmci_disabled = true;
+	else if (!strcmp(str, "no_lmce"))
+		cfg->lmce_disabled = 1;
+	else if (!strcmp(str, "dont_log_ce"))
+		cfg->dont_log_ce = true;
+	else if (!strcmp(str, "print_all"))
+		cfg->print_all = true;
+	else if (!strcmp(str, "ignore_ce"))
+		cfg->ignore_ce = true;
+	else if (!strcmp(str, "bootlog") || !strcmp(str, "nobootlog"))
+		cfg->bootlog = (str[0] == 'b');
+	else if (!strcmp(str, "bios_cmci_threshold"))
+		cfg->bios_cmci_threshold = 1;
+	else if (!strcmp(str, "recovery"))
+		cfg->recovery = 1;
+	else if (isdigit(str[0]))
+		get_option(&str, &(cfg->monarch_timeout));
+	else {
+		pr_info("mce argument %s ignored. Please use /sys\n", str);
+		return 0;
+	}
+	return 1;
+}
+__setup("mce", mcheck_enable);
+
+int __init mcheck_init(void)
+{
+	mce_register_decode_chain(&early_nb);
+	mce_register_decode_chain(&mce_uc_nb);
+	mce_register_decode_chain(&mce_default_nb);
+
+	INIT_WORK(&mce_work, mce_gen_pool_process);
+	init_irq_work(&mce_irq_work, mce_irq_work_cb);
+
+	return 0;
+}
+
+/*
+ * mce_syscore: PM support
+ */
+
+/*
+ * Disable machine checks on suspend and shutdown. We can't really handle
+ * them later.
+ */
+static void mce_disable_error_reporting(void)
+{
+	struct mce_bank *mce_banks = this_cpu_ptr(mce_banks_array);
+	int i;
+
+	for (i = 0; i < this_cpu_read(mce_num_banks); i++) {
+		struct mce_bank *b = &mce_banks[i];
+
+		if (b->init)
+			wrmsrl(mca_msr_reg(i, MCA_CTL), 0);
+	}
+	return;
+}
+
+static void vendor_disable_error_reporting(void)
+{
+	/*
+	 * Don't clear on Intel or AMD or Hygon or Zhaoxin CPUs. Some of these
+	 * MSRs are socket-wide. Disabling them for just a single offlined CPU
+	 * is bad, since it will inhibit reporting for all shared resources on
+	 * the socket like the last level cache (LLC), the integrated memory
+	 * controller (iMC), etc.
+	 */
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL ||
+	    boot_cpu_data.x86_vendor == X86_VENDOR_HYGON ||
+	    boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
+	    boot_cpu_data.x86_vendor == X86_VENDOR_ZHAOXIN)
+		return;
+
+	mce_disable_error_reporting();
+}
+
+static int mce_syscore_suspend(void)
+{
+	vendor_disable_error_reporting();
+	return 0;
+}
+
+static void mce_syscore_shutdown(void)
+{
+	vendor_disable_error_reporting();
+}
+
+/*
+ * On resume clear all MCE state. Don't want to see leftovers from the BIOS.
+ * Only one CPU is active at this time, the others get re-added later using
+ * CPU hotplug:
+ */
+static void mce_syscore_resume(void)
+{
+	__mcheck_cpu_init_generic();
+	__mcheck_cpu_init_vendor(raw_cpu_ptr(&cpu_info));
+	__mcheck_cpu_init_clear_banks();
+}
+
+static struct syscore_ops mce_syscore_ops = {
+	.suspend	= mce_syscore_suspend,
+	.shutdown	= mce_syscore_shutdown,
+	.resume		= mce_syscore_resume,
+};
+
+/*
+ * mce_device: Sysfs support
+ */
+
+static void mce_cpu_restart(void *data)
+{
+	if (!mce_available(raw_cpu_ptr(&cpu_info)))
+		return;
+	__mcheck_cpu_init_generic();
+	__mcheck_cpu_init_clear_banks();
+	__mcheck_cpu_init_timer();
+}
+
+/* Reinit MCEs after user configuration changes */
+static void mce_restart(void)
+{
+	mce_timer_delete_all();
+	on_each_cpu(mce_cpu_restart, NULL, 1);
+	mce_schedule_work();
+}
+
+/* Toggle features for corrected errors */
+static void mce_disable_cmci(void *data)
+{
+	if (!mce_available(raw_cpu_ptr(&cpu_info)))
+		return;
+	cmci_clear();
+}
+
+static void mce_enable_ce(void *all)
+{
+	if (!mce_available(raw_cpu_ptr(&cpu_info)))
+		return;
+	cmci_reenable();
+	cmci_recheck();
+	if (all)
+		__mcheck_cpu_init_timer();
+}
+
+static struct bus_type mce_subsys = {
+	.name		= "machinecheck",
+	.dev_name	= "machinecheck",
+};
+
+DEFINE_PER_CPU(struct device *, mce_device);
+
+static inline struct mce_bank_dev *attr_to_bank(struct device_attribute *attr)
+{
+	return container_of(attr, struct mce_bank_dev, attr);
+}
+
+static ssize_t show_bank(struct device *s, struct device_attribute *attr,
+			 char *buf)
+{
+	u8 bank = attr_to_bank(attr)->bank;
+	struct mce_bank *b;
+
+	if (bank >= per_cpu(mce_num_banks, s->id))
+		return -EINVAL;
+
+	b = &per_cpu(mce_banks_array, s->id)[bank];
+
+	if (!b->init)
+		return -ENODEV;
+
+	return sprintf(buf, "%llx\n", b->ctl);
+}
+
+static ssize_t set_bank(struct device *s, struct device_attribute *attr,
+			const char *buf, size_t size)
+{
+	u8 bank = attr_to_bank(attr)->bank;
+	struct mce_bank *b;
+	u64 new;
+
+	if (kstrtou64(buf, 0, &new) < 0)
+		return -EINVAL;
+
+	if (bank >= per_cpu(mce_num_banks, s->id))
+		return -EINVAL;
+
+	b = &per_cpu(mce_banks_array, s->id)[bank];
+
+	if (!b->init)
+		return -ENODEV;
+
+	b->ctl = new;
+	mce_restart();
+
+	return size;
+}
+
+static ssize_t set_ignore_ce(struct device *s,
+			     struct device_attribute *attr,
+			     const char *buf, size_t size)
+{
+	u64 new;
+
+	if (kstrtou64(buf, 0, &new) < 0)
+		return -EINVAL;
+
+	mutex_lock(&mce_sysfs_mutex);
+	if (mca_cfg.ignore_ce ^ !!new) {
+		if (new) {
+			/* disable ce features */
+			mce_timer_delete_all();
+			on_each_cpu(mce_disable_cmci, NULL, 1);
+			mca_cfg.ignore_ce = true;
+		} else {
+			/* enable ce features */
+			mca_cfg.ignore_ce = false;
+			on_each_cpu(mce_enable_ce, (void *)1, 1);
+		}
+	}
+	mutex_unlock(&mce_sysfs_mutex);
+
+	return size;
+}
+
+static ssize_t set_cmci_disabled(struct device *s,
+				 struct device_attribute *attr,
+				 const char *buf, size_t size)
+{
+	u64 new;
+
+	if (kstrtou64(buf, 0, &new) < 0)
+		return -EINVAL;
+
+	mutex_lock(&mce_sysfs_mutex);
+	if (mca_cfg.cmci_disabled ^ !!new) {
+		if (new) {
+			/* disable cmci */
+			on_each_cpu(mce_disable_cmci, NULL, 1);
+			mca_cfg.cmci_disabled = true;
+		} else {
+			/* enable cmci */
+			mca_cfg.cmci_disabled = false;
+			on_each_cpu(mce_enable_ce, NULL, 1);
+		}
+	}
+	mutex_unlock(&mce_sysfs_mutex);
+
+	return size;
+}
+
+static ssize_t store_int_with_restart(struct device *s,
+				      struct device_attribute *attr,
+				      const char *buf, size_t size)
+{
+	unsigned long old_check_interval = check_interval;
+	ssize_t ret = device_store_ulong(s, attr, buf, size);
+
+	if (check_interval == old_check_interval)
+		return ret;
+
+	mutex_lock(&mce_sysfs_mutex);
+	mce_restart();
+	mutex_unlock(&mce_sysfs_mutex);
+
+	return ret;
+}
+
+static DEVICE_INT_ATTR(monarch_timeout, 0644, mca_cfg.monarch_timeout);
+static DEVICE_BOOL_ATTR(dont_log_ce, 0644, mca_cfg.dont_log_ce);
+static DEVICE_BOOL_ATTR(print_all, 0644, mca_cfg.print_all);
+
+static struct dev_ext_attribute dev_attr_check_interval = {
+	__ATTR(check_interval, 0644, device_show_int, store_int_with_restart),
+	&check_interval
+};
+
+static struct dev_ext_attribute dev_attr_ignore_ce = {
+	__ATTR(ignore_ce, 0644, device_show_bool, set_ignore_ce),
+	&mca_cfg.ignore_ce
+};
+
+static struct dev_ext_attribute dev_attr_cmci_disabled = {
+	__ATTR(cmci_disabled, 0644, device_show_bool, set_cmci_disabled),
+	&mca_cfg.cmci_disabled
+};
+
+static struct device_attribute *mce_device_attrs[] = {
+	&dev_attr_check_interval.attr,
+#ifdef CONFIG_X86_MCELOG_LEGACY
+	&dev_attr_trigger,
+#endif
+	&dev_attr_monarch_timeout.attr,
+	&dev_attr_dont_log_ce.attr,
+	&dev_attr_print_all.attr,
+	&dev_attr_ignore_ce.attr,
+	&dev_attr_cmci_disabled.attr,
+	NULL
+};
+
+static cpumask_var_t mce_device_initialized;
+
+static void mce_device_release(struct device *dev)
+{
+	kfree(dev);
+}
+
+/* Per CPU device init. All of the CPUs still share the same bank device: */
+static int mce_device_create(unsigned int cpu)
+{
+	struct device *dev;
+	int err;
+	int i, j;
+
+	if (!mce_available(&boot_cpu_data))
+		return -EIO;
+
+	dev = per_cpu(mce_device, cpu);
+	if (dev)
+		return 0;
+
+	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		return -ENOMEM;
+	dev->id  = cpu;
+	dev->bus = &mce_subsys;
+	dev->release = &mce_device_release;
+
+	err = device_register(dev);
+	if (err) {
+		put_device(dev);
+		return err;
+	}
+
+	for (i = 0; mce_device_attrs[i]; i++) {
+		err = device_create_file(dev, mce_device_attrs[i]);
+		if (err)
+			goto error;
+	}
+	for (j = 0; j < per_cpu(mce_num_banks, cpu); j++) {
+		err = device_create_file(dev, &mce_bank_devs[j].attr);
+		if (err)
+			goto error2;
+	}
+	cpumask_set_cpu(cpu, mce_device_initialized);
+	per_cpu(mce_device, cpu) = dev;
+
+	return 0;
+error2:
+	while (--j >= 0)
+		device_remove_file(dev, &mce_bank_devs[j].attr);
+error:
+	while (--i >= 0)
+		device_remove_file(dev, mce_device_attrs[i]);
+
+	device_unregister(dev);
+
+	return err;
+}
+
+static void mce_device_remove(unsigned int cpu)
+{
+	struct device *dev = per_cpu(mce_device, cpu);
+	int i;
+
+	if (!cpumask_test_cpu(cpu, mce_device_initialized))
+		return;
+
+	for (i = 0; mce_device_attrs[i]; i++)
+		device_remove_file(dev, mce_device_attrs[i]);
+
+	for (i = 0; i < per_cpu(mce_num_banks, cpu); i++)
+		device_remove_file(dev, &mce_bank_devs[i].attr);
+
+	device_unregister(dev);
+	cpumask_clear_cpu(cpu, mce_device_initialized);
+	per_cpu(mce_device, cpu) = NULL;
+}
+
+/* Make sure there are no machine checks on offlined CPUs. */
+static void mce_disable_cpu(void)
+{
+	if (!mce_available(raw_cpu_ptr(&cpu_info)))
+		return;
+
+	if (!cpuhp_tasks_frozen)
+		cmci_clear();
+
+	vendor_disable_error_reporting();
+}
+
+static void mce_reenable_cpu(void)
+{
+	struct mce_bank *mce_banks = this_cpu_ptr(mce_banks_array);
+	int i;
+
+	if (!mce_available(raw_cpu_ptr(&cpu_info)))
+		return;
+
+	if (!cpuhp_tasks_frozen)
+		cmci_reenable();
+	for (i = 0; i < this_cpu_read(mce_num_banks); i++) {
+		struct mce_bank *b = &mce_banks[i];
+
+		if (b->init)
+			wrmsrl(mca_msr_reg(i, MCA_CTL), b->ctl);
+	}
+}
+
+static int mce_cpu_dead(unsigned int cpu)
+{
+	mce_intel_hcpu_update(cpu);
+
+	/* intentionally ignoring frozen here */
+	if (!cpuhp_tasks_frozen)
+		cmci_rediscover();
+	return 0;
+}
+
+static int mce_cpu_online(unsigned int cpu)
+{
+	struct timer_list *t = this_cpu_ptr(&mce_timer);
+	int ret;
+
+	mce_device_create(cpu);
+
+	ret = mce_threshold_create_device(cpu);
+	if (ret) {
+		mce_device_remove(cpu);
+		return ret;
+	}
+	mce_reenable_cpu();
+	mce_start_timer(t);
+	return 0;
+}
+
+static int mce_cpu_pre_down(unsigned int cpu)
+{
+	struct timer_list *t = this_cpu_ptr(&mce_timer);
+
+	mce_disable_cpu();
+	del_timer_sync(t);
+	mce_threshold_remove_device(cpu);
+	mce_device_remove(cpu);
+	return 0;
+}
+
+static __init void mce_init_banks(void)
+{
+	int i;
+
+	for (i = 0; i < MAX_NR_BANKS; i++) {
+		struct mce_bank_dev *b = &mce_bank_devs[i];
+		struct device_attribute *a = &b->attr;
+
+		b->bank = i;
+
+		sysfs_attr_init(&a->attr);
+		a->attr.name	= b->attrname;
+		snprintf(b->attrname, ATTR_LEN, "bank%d", i);
+
+		a->attr.mode	= 0644;
+		a->show		= show_bank;
+		a->store	= set_bank;
+	}
+}
+
+/*
+ * When running on XEN, this initcall is ordered against the XEN mcelog
+ * initcall:
+ *
+ *   device_initcall(xen_late_init_mcelog);
+ *   device_initcall_sync(mcheck_init_device);
+ */
+static __init int mcheck_init_device(void)
+{
+	int err;
+
+	/*
+	 * Check if we have a spare virtual bit. This will only become
+	 * a problem if/when we move beyond 5-level page tables.
+	 */
+	MAYBE_BUILD_BUG_ON(__VIRTUAL_MASK_SHIFT >= 63);
+
+	if (!mce_available(&boot_cpu_data)) {
+		err = -EIO;
+		goto err_out;
+	}
+
+	if (!zalloc_cpumask_var(&mce_device_initialized, GFP_KERNEL)) {
+		err = -ENOMEM;
+		goto err_out;
+	}
+
+	mce_init_banks();
+
+	err = subsys_system_register(&mce_subsys, NULL);
+	if (err)
+		goto err_out_mem;
+
+	err = cpuhp_setup_state(CPUHP_X86_MCE_DEAD, "x86/mce:dead", NULL,
+				mce_cpu_dead);
+	if (err)
+		goto err_out_mem;
+
+	/*
+	 * Invokes mce_cpu_online() on all CPUs which are online when
+	 * the state is installed.
+	 */
+	err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/mce:online",
+				mce_cpu_online, mce_cpu_pre_down);
+	if (err < 0)
+		goto err_out_online;
+
+	register_syscore_ops(&mce_syscore_ops);
+
+	return 0;
+
+err_out_online:
+	cpuhp_remove_state(CPUHP_X86_MCE_DEAD);
+
+err_out_mem:
+	free_cpumask_var(mce_device_initialized);
+
+err_out:
+	pr_err("Unable to init MCE device (rc: %d)\n", err);
+
+	return err;
+}
+device_initcall_sync(mcheck_init_device);
+
+/*
+ * Old style boot options parsing. Only for compatibility.
+ */
+static int __init mcheck_disable(char *str)
+{
+	mca_cfg.disabled = 1;
+	return 1;
+}
+__setup("nomce", mcheck_disable);
+
+#ifdef CONFIG_DEBUG_FS
+struct dentry *mce_get_debugfs_dir(void)
+{
+	static struct dentry *dmce;
+
+	if (!dmce)
+		dmce = debugfs_create_dir("mce", NULL);
+
+	return dmce;
+}
+
+static void mce_reset(void)
+{
+	atomic_set(&mce_fake_panicked, 0);
+	atomic_set(&mce_executing, 0);
+	atomic_set(&mce_callin, 0);
+	atomic_set(&global_nwo, 0);
+	cpumask_setall(&mce_missing_cpus);
+}
+
+static int fake_panic_get(void *data, u64 *val)
+{
+	*val = fake_panic;
+	return 0;
+}
+
+static int fake_panic_set(void *data, u64 val)
+{
+	mce_reset();
+	fake_panic = val;
+	return 0;
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(fake_panic_fops, fake_panic_get, fake_panic_set,
+			 "%llu\n");
+
+static void __init mcheck_debugfs_init(void)
+{
+	struct dentry *dmce;
+
+	dmce = mce_get_debugfs_dir();
+	debugfs_create_file_unsafe("fake_panic", 0444, dmce, NULL,
+				   &fake_panic_fops);
+}
+#else
+static void __init mcheck_debugfs_init(void) { }
+#endif
+
+static int __init mcheck_late_init(void)
+{
+	if (mca_cfg.recovery)
+		enable_copy_mc_fragile();
+
+	mcheck_debugfs_init();
+
+	/*
+	 * Flush out everything that has been logged during early boot, now that
+	 * everything has been initialized (workqueues, decoders, ...).
+	 */
+	mce_schedule_work();
+
+	return 0;
+}
+late_initcall(mcheck_late_init);
diff --git a/arch/x86/kernel/cpu/mce/dev-mcelog.c b/arch/x86/kernel/cpu/mce/dev-mcelog.c
new file mode 100644
index 0000000000..a05ac0716e
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/dev-mcelog.c
@@ -0,0 +1,373 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * /dev/mcelog driver
+ *
+ * K8 parts Copyright 2002,2003 Andi Kleen, SuSE Labs.
+ * Rest from unknown author(s).
+ * 2004 Andi Kleen. Rewrote most of it.
+ * Copyright 2008 Intel Corporation
+ * Author: Andi Kleen
+ */
+
+#include <linux/miscdevice.h>
+#include <linux/slab.h>
+#include <linux/kmod.h>
+#include <linux/poll.h>
+
+#include "internal.h"
+
+static BLOCKING_NOTIFIER_HEAD(mce_injector_chain);
+
+static DEFINE_MUTEX(mce_chrdev_read_mutex);
+
+static char mce_helper[128];
+static char *mce_helper_argv[2] = { mce_helper, NULL };
+
+/*
+ * Lockless MCE logging infrastructure.
+ * This avoids deadlocks on printk locks without having to break locks. Also
+ * separate MCEs from kernel messages to avoid bogus bug reports.
+ */
+
+static struct mce_log_buffer *mcelog;
+
+static DECLARE_WAIT_QUEUE_HEAD(mce_chrdev_wait);
+
+static int dev_mce_log(struct notifier_block *nb, unsigned long val,
+				void *data)
+{
+	struct mce *mce = (struct mce *)data;
+	unsigned int entry;
+
+	if (mce->kflags & MCE_HANDLED_CEC)
+		return NOTIFY_DONE;
+
+	mutex_lock(&mce_chrdev_read_mutex);
+
+	entry = mcelog->next;
+
+	/*
+	 * When the buffer fills up discard new entries. Assume that the
+	 * earlier errors are the more interesting ones:
+	 */
+	if (entry >= mcelog->len) {
+		set_bit(MCE_OVERFLOW, (unsigned long *)&mcelog->flags);
+		goto unlock;
+	}
+
+	mcelog->next = entry + 1;
+
+	memcpy(mcelog->entry + entry, mce, sizeof(struct mce));
+	mcelog->entry[entry].finished = 1;
+	mcelog->entry[entry].kflags = 0;
+
+	/* wake processes polling /dev/mcelog */
+	wake_up_interruptible(&mce_chrdev_wait);
+
+unlock:
+	mutex_unlock(&mce_chrdev_read_mutex);
+
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
+		mce->kflags |= MCE_HANDLED_MCELOG;
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block dev_mcelog_nb = {
+	.notifier_call	= dev_mce_log,
+	.priority	= MCE_PRIO_MCELOG,
+};
+
+static void mce_do_trigger(struct work_struct *work)
+{
+	call_usermodehelper(mce_helper, mce_helper_argv, NULL, UMH_NO_WAIT);
+}
+
+static DECLARE_WORK(mce_trigger_work, mce_do_trigger);
+
+
+void mce_work_trigger(void)
+{
+	if (mce_helper[0])
+		schedule_work(&mce_trigger_work);
+}
+
+static ssize_t
+show_trigger(struct device *s, struct device_attribute *attr, char *buf)
+{
+	strcpy(buf, mce_helper);
+	strcat(buf, "\n");
+	return strlen(mce_helper) + 1;
+}
+
+static ssize_t set_trigger(struct device *s, struct device_attribute *attr,
+				const char *buf, size_t siz)
+{
+	char *p;
+
+	strscpy(mce_helper, buf, sizeof(mce_helper));
+	p = strchr(mce_helper, '\n');
+
+	if (p)
+		*p = 0;
+
+	return strlen(mce_helper) + !!p;
+}
+
+DEVICE_ATTR(trigger, 0644, show_trigger, set_trigger);
+
+/*
+ * mce_chrdev: Character device /dev/mcelog to read and clear the MCE log.
+ */
+
+static DEFINE_SPINLOCK(mce_chrdev_state_lock);
+static int mce_chrdev_open_count;	/* #times opened */
+static int mce_chrdev_open_exclu;	/* already open exclusive? */
+
+static int mce_chrdev_open(struct inode *inode, struct file *file)
+{
+	spin_lock(&mce_chrdev_state_lock);
+
+	if (mce_chrdev_open_exclu ||
+	    (mce_chrdev_open_count && (file->f_flags & O_EXCL))) {
+		spin_unlock(&mce_chrdev_state_lock);
+
+		return -EBUSY;
+	}
+
+	if (file->f_flags & O_EXCL)
+		mce_chrdev_open_exclu = 1;
+	mce_chrdev_open_count++;
+
+	spin_unlock(&mce_chrdev_state_lock);
+
+	return nonseekable_open(inode, file);
+}
+
+static int mce_chrdev_release(struct inode *inode, struct file *file)
+{
+	spin_lock(&mce_chrdev_state_lock);
+
+	mce_chrdev_open_count--;
+	mce_chrdev_open_exclu = 0;
+
+	spin_unlock(&mce_chrdev_state_lock);
+
+	return 0;
+}
+
+static int mce_apei_read_done;
+
+/* Collect MCE record of previous boot in persistent storage via APEI ERST. */
+static int __mce_read_apei(char __user **ubuf, size_t usize)
+{
+	int rc;
+	u64 record_id;
+	struct mce m;
+
+	if (usize < sizeof(struct mce))
+		return -EINVAL;
+
+	rc = apei_read_mce(&m, &record_id);
+	/* Error or no more MCE record */
+	if (rc <= 0) {
+		mce_apei_read_done = 1;
+		/*
+		 * When ERST is disabled, mce_chrdev_read() should return
+		 * "no record" instead of "no device."
+		 */
+		if (rc == -ENODEV)
+			return 0;
+		return rc;
+	}
+	rc = -EFAULT;
+	if (copy_to_user(*ubuf, &m, sizeof(struct mce)))
+		return rc;
+	/*
+	 * In fact, we should have cleared the record after that has
+	 * been flushed to the disk or sent to network in
+	 * /sbin/mcelog, but we have no interface to support that now,
+	 * so just clear it to avoid duplication.
+	 */
+	rc = apei_clear_mce(record_id);
+	if (rc) {
+		mce_apei_read_done = 1;
+		return rc;
+	}
+	*ubuf += sizeof(struct mce);
+
+	return 0;
+}
+
+static ssize_t mce_chrdev_read(struct file *filp, char __user *ubuf,
+				size_t usize, loff_t *off)
+{
+	char __user *buf = ubuf;
+	unsigned next;
+	int i, err;
+
+	mutex_lock(&mce_chrdev_read_mutex);
+
+	if (!mce_apei_read_done) {
+		err = __mce_read_apei(&buf, usize);
+		if (err || buf != ubuf)
+			goto out;
+	}
+
+	/* Only supports full reads right now */
+	err = -EINVAL;
+	if (*off != 0 || usize < mcelog->len * sizeof(struct mce))
+		goto out;
+
+	next = mcelog->next;
+	err = 0;
+
+	for (i = 0; i < next; i++) {
+		struct mce *m = &mcelog->entry[i];
+
+		err |= copy_to_user(buf, m, sizeof(*m));
+		buf += sizeof(*m);
+	}
+
+	memset(mcelog->entry, 0, next * sizeof(struct mce));
+	mcelog->next = 0;
+
+	if (err)
+		err = -EFAULT;
+
+out:
+	mutex_unlock(&mce_chrdev_read_mutex);
+
+	return err ? err : buf - ubuf;
+}
+
+static __poll_t mce_chrdev_poll(struct file *file, poll_table *wait)
+{
+	poll_wait(file, &mce_chrdev_wait, wait);
+	if (READ_ONCE(mcelog->next))
+		return EPOLLIN | EPOLLRDNORM;
+	if (!mce_apei_read_done && apei_check_mce())
+		return EPOLLIN | EPOLLRDNORM;
+	return 0;
+}
+
+static long mce_chrdev_ioctl(struct file *f, unsigned int cmd,
+				unsigned long arg)
+{
+	int __user *p = (int __user *)arg;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	switch (cmd) {
+	case MCE_GET_RECORD_LEN:
+		return put_user(sizeof(struct mce), p);
+	case MCE_GET_LOG_LEN:
+		return put_user(mcelog->len, p);
+	case MCE_GETCLEAR_FLAGS: {
+		unsigned flags;
+
+		do {
+			flags = mcelog->flags;
+		} while (cmpxchg(&mcelog->flags, flags, 0) != flags);
+
+		return put_user(flags, p);
+	}
+	default:
+		return -ENOTTY;
+	}
+}
+
+void mce_register_injector_chain(struct notifier_block *nb)
+{
+	blocking_notifier_chain_register(&mce_injector_chain, nb);
+}
+EXPORT_SYMBOL_GPL(mce_register_injector_chain);
+
+void mce_unregister_injector_chain(struct notifier_block *nb)
+{
+	blocking_notifier_chain_unregister(&mce_injector_chain, nb);
+}
+EXPORT_SYMBOL_GPL(mce_unregister_injector_chain);
+
+static ssize_t mce_chrdev_write(struct file *filp, const char __user *ubuf,
+				size_t usize, loff_t *off)
+{
+	struct mce m;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+	/*
+	 * There are some cases where real MSR reads could slip
+	 * through.
+	 */
+	if (!boot_cpu_has(X86_FEATURE_MCE) || !boot_cpu_has(X86_FEATURE_MCA))
+		return -EIO;
+
+	if ((unsigned long)usize > sizeof(struct mce))
+		usize = sizeof(struct mce);
+	if (copy_from_user(&m, ubuf, usize))
+		return -EFAULT;
+
+	if (m.extcpu >= num_possible_cpus() || !cpu_online(m.extcpu))
+		return -EINVAL;
+
+	/*
+	 * Need to give user space some time to set everything up,
+	 * so do it a jiffie or two later everywhere.
+	 */
+	schedule_timeout(2);
+
+	blocking_notifier_call_chain(&mce_injector_chain, 0, &m);
+
+	return usize;
+}
+
+static const struct file_operations mce_chrdev_ops = {
+	.open			= mce_chrdev_open,
+	.release		= mce_chrdev_release,
+	.read			= mce_chrdev_read,
+	.write			= mce_chrdev_write,
+	.poll			= mce_chrdev_poll,
+	.unlocked_ioctl		= mce_chrdev_ioctl,
+	.compat_ioctl		= compat_ptr_ioctl,
+	.llseek			= no_llseek,
+};
+
+static struct miscdevice mce_chrdev_device = {
+	MISC_MCELOG_MINOR,
+	"mcelog",
+	&mce_chrdev_ops,
+};
+
+static __init int dev_mcelog_init_device(void)
+{
+	int mce_log_len;
+	int err;
+
+	mce_log_len = max(MCE_LOG_MIN_LEN, num_online_cpus());
+	mcelog = kzalloc(struct_size(mcelog, entry, mce_log_len), GFP_KERNEL);
+	if (!mcelog)
+		return -ENOMEM;
+
+	memcpy(mcelog->signature, MCE_LOG_SIGNATURE, sizeof(mcelog->signature));
+	mcelog->len = mce_log_len;
+	mcelog->recordlen = sizeof(struct mce);
+
+	/* register character device /dev/mcelog */
+	err = misc_register(&mce_chrdev_device);
+	if (err) {
+		if (err == -EBUSY)
+			/* Xen dom0 might have registered the device already. */
+			pr_info("Unable to init device /dev/mcelog, already registered");
+		else
+			pr_err("Unable to init device /dev/mcelog (rc: %d)\n", err);
+
+		kfree(mcelog);
+		return err;
+	}
+
+	mce_register_decode_chain(&dev_mcelog_nb);
+	return 0;
+}
+device_initcall_sync(dev_mcelog_init_device);
diff --git a/arch/x86/kernel/cpu/mce/genpool.c b/arch/x86/kernel/cpu/mce/genpool.c
new file mode 100644
index 0000000000..fbe8b61c34
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/genpool.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * MCE event pool management in MCE context
+ *
+ * Copyright (C) 2015 Intel Corp.
+ * Author: Chen, Gong <gong.chen@linux.intel.com>
+ */
+#include <linux/smp.h>
+#include <linux/mm.h>
+#include <linux/genalloc.h>
+#include <linux/llist.h>
+#include "internal.h"
+
+/*
+ * printk() is not safe in MCE context. This is a lock-less memory allocator
+ * used to save error information organized in a lock-less list.
+ *
+ * This memory pool is only to be used to save MCE records in MCE context.
+ * MCE events are rare, so a fixed size memory pool should be enough. Use
+ * 2 pages to save MCE events for now (~80 MCE records at most).
+ */
+#define MCE_POOLSZ	(2 * PAGE_SIZE)
+
+static struct gen_pool *mce_evt_pool;
+static LLIST_HEAD(mce_event_llist);
+static char gen_pool_buf[MCE_POOLSZ];
+
+/*
+ * Compare the record "t" with each of the records on list "l" to see if
+ * an equivalent one is present in the list.
+ */
+static bool is_duplicate_mce_record(struct mce_evt_llist *t, struct mce_evt_llist *l)
+{
+	struct mce_evt_llist *node;
+	struct mce *m1, *m2;
+
+	m1 = &t->mce;
+
+	llist_for_each_entry(node, &l->llnode, llnode) {
+		m2 = &node->mce;
+
+		if (!mce_cmp(m1, m2))
+			return true;
+	}
+	return false;
+}
+
+/*
+ * The system has panicked - we'd like to peruse the list of MCE records
+ * that have been queued, but not seen by anyone yet.  The list is in
+ * reverse time order, so we need to reverse it. While doing that we can
+ * also drop duplicate records (these were logged because some banks are
+ * shared between cores or by all threads on a socket).
+ */
+struct llist_node *mce_gen_pool_prepare_records(void)
+{
+	struct llist_node *head;
+	LLIST_HEAD(new_head);
+	struct mce_evt_llist *node, *t;
+
+	head = llist_del_all(&mce_event_llist);
+	if (!head)
+		return NULL;
+
+	/* squeeze out duplicates while reversing order */
+	llist_for_each_entry_safe(node, t, head, llnode) {
+		if (!is_duplicate_mce_record(node, t))
+			llist_add(&node->llnode, &new_head);
+	}
+
+	return new_head.first;
+}
+
+void mce_gen_pool_process(struct work_struct *__unused)
+{
+	struct llist_node *head;
+	struct mce_evt_llist *node, *tmp;
+	struct mce *mce;
+
+	head = llist_del_all(&mce_event_llist);
+	if (!head)
+		return;
+
+	head = llist_reverse_order(head);
+	llist_for_each_entry_safe(node, tmp, head, llnode) {
+		mce = &node->mce;
+		blocking_notifier_call_chain(&x86_mce_decoder_chain, 0, mce);
+		gen_pool_free(mce_evt_pool, (unsigned long)node, sizeof(*node));
+	}
+}
+
+bool mce_gen_pool_empty(void)
+{
+	return llist_empty(&mce_event_llist);
+}
+
+int mce_gen_pool_add(struct mce *mce)
+{
+	struct mce_evt_llist *node;
+
+	if (filter_mce(mce))
+		return -EINVAL;
+
+	if (!mce_evt_pool)
+		return -EINVAL;
+
+	node = (void *)gen_pool_alloc(mce_evt_pool, sizeof(*node));
+	if (!node) {
+		pr_warn_ratelimited("MCE records pool full!\n");
+		return -ENOMEM;
+	}
+
+	memcpy(&node->mce, mce, sizeof(*mce));
+	llist_add(&node->llnode, &mce_event_llist);
+
+	return 0;
+}
+
+static int mce_gen_pool_create(void)
+{
+	struct gen_pool *tmpp;
+	int ret = -ENOMEM;
+
+	tmpp = gen_pool_create(ilog2(sizeof(struct mce_evt_llist)), -1);
+	if (!tmpp)
+		goto out;
+
+	ret = gen_pool_add(tmpp, (unsigned long)gen_pool_buf, MCE_POOLSZ, -1);
+	if (ret) {
+		gen_pool_destroy(tmpp);
+		goto out;
+	}
+
+	mce_evt_pool = tmpp;
+
+out:
+	return ret;
+}
+
+int mce_gen_pool_init(void)
+{
+	/* Just init mce_gen_pool once. */
+	if (mce_evt_pool)
+		return 0;
+
+	return mce_gen_pool_create();
+}
diff --git a/arch/x86/kernel/cpu/mce/inject.c b/arch/x86/kernel/cpu/mce/inject.c
new file mode 100644
index 0000000000..72f0695c3d
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/inject.c
@@ -0,0 +1,800 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Machine check injection support.
+ * Copyright 2008 Intel Corporation.
+ *
+ * Authors:
+ * Andi Kleen
+ * Ying Huang
+ *
+ * The AMD part (from mce_amd_inj.c): a simple MCE injection facility
+ * for testing different aspects of the RAS code. This driver should be
+ * built as module so that it can be loaded on production kernels for
+ * testing purposes.
+ *
+ * Copyright (c) 2010-17:  Borislav Petkov <bp@alien8.de>
+ *			   Advanced Micro Devices Inc.
+ */
+
+#include <linux/cpu.h>
+#include <linux/debugfs.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/pci.h>
+#include <linux/uaccess.h>
+
+#include <asm/amd_nb.h>
+#include <asm/apic.h>
+#include <asm/irq_vectors.h>
+#include <asm/mce.h>
+#include <asm/nmi.h>
+#include <asm/smp.h>
+
+#include "internal.h"
+
+static bool hw_injection_possible = true;
+
+/*
+ * Collect all the MCi_XXX settings
+ */
+static struct mce i_mce;
+static struct dentry *dfs_inj;
+
+#define MAX_FLAG_OPT_SIZE	4
+#define NBCFG			0x44
+
+enum injection_type {
+	SW_INJ = 0,	/* SW injection, simply decode the error */
+	HW_INJ,		/* Trigger a #MC */
+	DFR_INT_INJ,    /* Trigger Deferred error interrupt */
+	THR_INT_INJ,    /* Trigger threshold interrupt */
+	N_INJ_TYPES,
+};
+
+static const char * const flags_options[] = {
+	[SW_INJ] = "sw",
+	[HW_INJ] = "hw",
+	[DFR_INT_INJ] = "df",
+	[THR_INT_INJ] = "th",
+	NULL
+};
+
+/* Set default injection to SW_INJ */
+static enum injection_type inj_type = SW_INJ;
+
+#define MCE_INJECT_SET(reg)						\
+static int inj_##reg##_set(void *data, u64 val)				\
+{									\
+	struct mce *m = (struct mce *)data;				\
+									\
+	m->reg = val;							\
+	return 0;							\
+}
+
+MCE_INJECT_SET(status);
+MCE_INJECT_SET(misc);
+MCE_INJECT_SET(addr);
+MCE_INJECT_SET(synd);
+
+#define MCE_INJECT_GET(reg)						\
+static int inj_##reg##_get(void *data, u64 *val)			\
+{									\
+	struct mce *m = (struct mce *)data;				\
+									\
+	*val = m->reg;							\
+	return 0;							\
+}
+
+MCE_INJECT_GET(status);
+MCE_INJECT_GET(misc);
+MCE_INJECT_GET(addr);
+MCE_INJECT_GET(synd);
+MCE_INJECT_GET(ipid);
+
+DEFINE_SIMPLE_ATTRIBUTE(status_fops, inj_status_get, inj_status_set, "%llx\n");
+DEFINE_SIMPLE_ATTRIBUTE(misc_fops, inj_misc_get, inj_misc_set, "%llx\n");
+DEFINE_SIMPLE_ATTRIBUTE(addr_fops, inj_addr_get, inj_addr_set, "%llx\n");
+DEFINE_SIMPLE_ATTRIBUTE(synd_fops, inj_synd_get, inj_synd_set, "%llx\n");
+
+/* Use the user provided IPID value on a sw injection. */
+static int inj_ipid_set(void *data, u64 val)
+{
+	struct mce *m = (struct mce *)data;
+
+	if (cpu_feature_enabled(X86_FEATURE_SMCA)) {
+		if (inj_type == SW_INJ)
+			m->ipid = val;
+	}
+
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(ipid_fops, inj_ipid_get, inj_ipid_set, "%llx\n");
+
+static void setup_inj_struct(struct mce *m)
+{
+	memset(m, 0, sizeof(struct mce));
+
+	m->cpuvendor = boot_cpu_data.x86_vendor;
+	m->time	     = ktime_get_real_seconds();
+	m->cpuid     = cpuid_eax(1);
+	m->microcode = boot_cpu_data.microcode;
+}
+
+/* Update fake mce registers on current CPU. */
+static void inject_mce(struct mce *m)
+{
+	struct mce *i = &per_cpu(injectm, m->extcpu);
+
+	/* Make sure no one reads partially written injectm */
+	i->finished = 0;
+	mb();
+	m->finished = 0;
+	/* First set the fields after finished */
+	i->extcpu = m->extcpu;
+	mb();
+	/* Now write record in order, finished last (except above) */
+	memcpy(i, m, sizeof(struct mce));
+	/* Finally activate it */
+	mb();
+	i->finished = 1;
+}
+
+static void raise_poll(struct mce *m)
+{
+	unsigned long flags;
+	mce_banks_t b;
+
+	memset(&b, 0xff, sizeof(mce_banks_t));
+	local_irq_save(flags);
+	machine_check_poll(0, &b);
+	local_irq_restore(flags);
+	m->finished = 0;
+}
+
+static void raise_exception(struct mce *m, struct pt_regs *pregs)
+{
+	struct pt_regs regs;
+	unsigned long flags;
+
+	if (!pregs) {
+		memset(&regs, 0, sizeof(struct pt_regs));
+		regs.ip = m->ip;
+		regs.cs = m->cs;
+		pregs = &regs;
+	}
+	/* do_machine_check() expects interrupts disabled -- at least */
+	local_irq_save(flags);
+	do_machine_check(pregs);
+	local_irq_restore(flags);
+	m->finished = 0;
+}
+
+static cpumask_var_t mce_inject_cpumask;
+static DEFINE_MUTEX(mce_inject_mutex);
+
+static int mce_raise_notify(unsigned int cmd, struct pt_regs *regs)
+{
+	int cpu = smp_processor_id();
+	struct mce *m = this_cpu_ptr(&injectm);
+	if (!cpumask_test_cpu(cpu, mce_inject_cpumask))
+		return NMI_DONE;
+	cpumask_clear_cpu(cpu, mce_inject_cpumask);
+	if (m->inject_flags & MCJ_EXCEPTION)
+		raise_exception(m, regs);
+	else if (m->status)
+		raise_poll(m);
+	return NMI_HANDLED;
+}
+
+static void mce_irq_ipi(void *info)
+{
+	int cpu = smp_processor_id();
+	struct mce *m = this_cpu_ptr(&injectm);
+
+	if (cpumask_test_cpu(cpu, mce_inject_cpumask) &&
+			m->inject_flags & MCJ_EXCEPTION) {
+		cpumask_clear_cpu(cpu, mce_inject_cpumask);
+		raise_exception(m, NULL);
+	}
+}
+
+/* Inject mce on current CPU */
+static int raise_local(void)
+{
+	struct mce *m = this_cpu_ptr(&injectm);
+	int context = MCJ_CTX(m->inject_flags);
+	int ret = 0;
+	int cpu = m->extcpu;
+
+	if (m->inject_flags & MCJ_EXCEPTION) {
+		pr_info("Triggering MCE exception on CPU %d\n", cpu);
+		switch (context) {
+		case MCJ_CTX_IRQ:
+			/*
+			 * Could do more to fake interrupts like
+			 * calling irq_enter, but the necessary
+			 * machinery isn't exported currently.
+			 */
+			fallthrough;
+		case MCJ_CTX_PROCESS:
+			raise_exception(m, NULL);
+			break;
+		default:
+			pr_info("Invalid MCE context\n");
+			ret = -EINVAL;
+		}
+		pr_info("MCE exception done on CPU %d\n", cpu);
+	} else if (m->status) {
+		pr_info("Starting machine check poll CPU %d\n", cpu);
+		raise_poll(m);
+		mce_notify_irq();
+		pr_info("Machine check poll done on CPU %d\n", cpu);
+	} else
+		m->finished = 0;
+
+	return ret;
+}
+
+static void __maybe_unused raise_mce(struct mce *m)
+{
+	int context = MCJ_CTX(m->inject_flags);
+
+	inject_mce(m);
+
+	if (context == MCJ_CTX_RANDOM)
+		return;
+
+	if (m->inject_flags & (MCJ_IRQ_BROADCAST | MCJ_NMI_BROADCAST)) {
+		unsigned long start;
+		int cpu;
+
+		cpus_read_lock();
+		cpumask_copy(mce_inject_cpumask, cpu_online_mask);
+		cpumask_clear_cpu(get_cpu(), mce_inject_cpumask);
+		for_each_online_cpu(cpu) {
+			struct mce *mcpu = &per_cpu(injectm, cpu);
+			if (!mcpu->finished ||
+			    MCJ_CTX(mcpu->inject_flags) != MCJ_CTX_RANDOM)
+				cpumask_clear_cpu(cpu, mce_inject_cpumask);
+		}
+		if (!cpumask_empty(mce_inject_cpumask)) {
+			if (m->inject_flags & MCJ_IRQ_BROADCAST) {
+				/*
+				 * don't wait because mce_irq_ipi is necessary
+				 * to be sync with following raise_local
+				 */
+				preempt_disable();
+				smp_call_function_many(mce_inject_cpumask,
+					mce_irq_ipi, NULL, 0);
+				preempt_enable();
+			} else if (m->inject_flags & MCJ_NMI_BROADCAST)
+				__apic_send_IPI_mask(mce_inject_cpumask, NMI_VECTOR);
+		}
+		start = jiffies;
+		while (!cpumask_empty(mce_inject_cpumask)) {
+			if (!time_before(jiffies, start + 2*HZ)) {
+				pr_err("Timeout waiting for mce inject %lx\n",
+					*cpumask_bits(mce_inject_cpumask));
+				break;
+			}
+			cpu_relax();
+		}
+		raise_local();
+		put_cpu();
+		cpus_read_unlock();
+	} else {
+		preempt_disable();
+		raise_local();
+		preempt_enable();
+	}
+}
+
+static int mce_inject_raise(struct notifier_block *nb, unsigned long val,
+			    void *data)
+{
+	struct mce *m = (struct mce *)data;
+
+	if (!m)
+		return NOTIFY_DONE;
+
+	mutex_lock(&mce_inject_mutex);
+	raise_mce(m);
+	mutex_unlock(&mce_inject_mutex);
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block inject_nb = {
+	.notifier_call  = mce_inject_raise,
+};
+
+/*
+ * Caller needs to be make sure this cpu doesn't disappear
+ * from under us, i.e.: get_cpu/put_cpu.
+ */
+static int toggle_hw_mce_inject(unsigned int cpu, bool enable)
+{
+	u32 l, h;
+	int err;
+
+	err = rdmsr_on_cpu(cpu, MSR_K7_HWCR, &l, &h);
+	if (err) {
+		pr_err("%s: error reading HWCR\n", __func__);
+		return err;
+	}
+
+	enable ? (l |= BIT(18)) : (l &= ~BIT(18));
+
+	err = wrmsr_on_cpu(cpu, MSR_K7_HWCR, l, h);
+	if (err)
+		pr_err("%s: error writing HWCR\n", __func__);
+
+	return err;
+}
+
+static int __set_inj(const char *buf)
+{
+	int i;
+
+	for (i = 0; i < N_INJ_TYPES; i++) {
+		if (!strncmp(flags_options[i], buf, strlen(flags_options[i]))) {
+			if (i > SW_INJ && !hw_injection_possible)
+				continue;
+			inj_type = i;
+			return 0;
+		}
+	}
+	return -EINVAL;
+}
+
+static ssize_t flags_read(struct file *filp, char __user *ubuf,
+			  size_t cnt, loff_t *ppos)
+{
+	char buf[MAX_FLAG_OPT_SIZE];
+	int n;
+
+	n = sprintf(buf, "%s\n", flags_options[inj_type]);
+
+	return simple_read_from_buffer(ubuf, cnt, ppos, buf, n);
+}
+
+static ssize_t flags_write(struct file *filp, const char __user *ubuf,
+			   size_t cnt, loff_t *ppos)
+{
+	char buf[MAX_FLAG_OPT_SIZE], *__buf;
+	int err;
+
+	if (!cnt || cnt > MAX_FLAG_OPT_SIZE)
+		return -EINVAL;
+
+	if (copy_from_user(&buf, ubuf, cnt))
+		return -EFAULT;
+
+	buf[cnt - 1] = 0;
+
+	/* strip whitespace */
+	__buf = strstrip(buf);
+
+	err = __set_inj(__buf);
+	if (err) {
+		pr_err("%s: Invalid flags value: %s\n", __func__, __buf);
+		return err;
+	}
+
+	*ppos += cnt;
+
+	return cnt;
+}
+
+static const struct file_operations flags_fops = {
+	.read           = flags_read,
+	.write          = flags_write,
+	.llseek         = generic_file_llseek,
+};
+
+/*
+ * On which CPU to inject?
+ */
+MCE_INJECT_GET(extcpu);
+
+static int inj_extcpu_set(void *data, u64 val)
+{
+	struct mce *m = (struct mce *)data;
+
+	if (val >= nr_cpu_ids || !cpu_online(val)) {
+		pr_err("%s: Invalid CPU: %llu\n", __func__, val);
+		return -EINVAL;
+	}
+	m->extcpu = val;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(extcpu_fops, inj_extcpu_get, inj_extcpu_set, "%llu\n");
+
+static void trigger_mce(void *info)
+{
+	asm volatile("int $18");
+}
+
+static void trigger_dfr_int(void *info)
+{
+	asm volatile("int %0" :: "i" (DEFERRED_ERROR_VECTOR));
+}
+
+static void trigger_thr_int(void *info)
+{
+	asm volatile("int %0" :: "i" (THRESHOLD_APIC_VECTOR));
+}
+
+static u32 get_nbc_for_node(int node_id)
+{
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+	u32 cores_per_node;
+
+	cores_per_node = (c->x86_max_cores * smp_num_siblings) / amd_get_nodes_per_socket();
+
+	return cores_per_node * node_id;
+}
+
+static void toggle_nb_mca_mst_cpu(u16 nid)
+{
+	struct amd_northbridge *nb;
+	struct pci_dev *F3;
+	u32 val;
+	int err;
+
+	nb = node_to_amd_nb(nid);
+	if (!nb)
+		return;
+
+	F3 = nb->misc;
+	if (!F3)
+		return;
+
+	err = pci_read_config_dword(F3, NBCFG, &val);
+	if (err) {
+		pr_err("%s: Error reading F%dx%03x.\n",
+		       __func__, PCI_FUNC(F3->devfn), NBCFG);
+		return;
+	}
+
+	if (val & BIT(27))
+		return;
+
+	pr_err("%s: Set D18F3x44[NbMcaToMstCpuEn] which BIOS hasn't done.\n",
+	       __func__);
+
+	val |= BIT(27);
+	err = pci_write_config_dword(F3, NBCFG, val);
+	if (err)
+		pr_err("%s: Error writing F%dx%03x.\n",
+		       __func__, PCI_FUNC(F3->devfn), NBCFG);
+}
+
+static void prepare_msrs(void *info)
+{
+	struct mce m = *(struct mce *)info;
+	u8 b = m.bank;
+
+	wrmsrl(MSR_IA32_MCG_STATUS, m.mcgstatus);
+
+	if (boot_cpu_has(X86_FEATURE_SMCA)) {
+		if (m.inject_flags == DFR_INT_INJ) {
+			wrmsrl(MSR_AMD64_SMCA_MCx_DESTAT(b), m.status);
+			wrmsrl(MSR_AMD64_SMCA_MCx_DEADDR(b), m.addr);
+		} else {
+			wrmsrl(MSR_AMD64_SMCA_MCx_STATUS(b), m.status);
+			wrmsrl(MSR_AMD64_SMCA_MCx_ADDR(b), m.addr);
+		}
+
+		wrmsrl(MSR_AMD64_SMCA_MCx_MISC(b), m.misc);
+		wrmsrl(MSR_AMD64_SMCA_MCx_SYND(b), m.synd);
+	} else {
+		wrmsrl(MSR_IA32_MCx_STATUS(b), m.status);
+		wrmsrl(MSR_IA32_MCx_ADDR(b), m.addr);
+		wrmsrl(MSR_IA32_MCx_MISC(b), m.misc);
+	}
+}
+
+static void do_inject(void)
+{
+	u64 mcg_status = 0;
+	unsigned int cpu = i_mce.extcpu;
+	u8 b = i_mce.bank;
+
+	i_mce.tsc = rdtsc_ordered();
+
+	i_mce.status |= MCI_STATUS_VAL;
+
+	if (i_mce.misc)
+		i_mce.status |= MCI_STATUS_MISCV;
+
+	if (i_mce.synd)
+		i_mce.status |= MCI_STATUS_SYNDV;
+
+	if (inj_type == SW_INJ) {
+		mce_log(&i_mce);
+		return;
+	}
+
+	/* prep MCE global settings for the injection */
+	mcg_status = MCG_STATUS_MCIP | MCG_STATUS_EIPV;
+
+	if (!(i_mce.status & MCI_STATUS_PCC))
+		mcg_status |= MCG_STATUS_RIPV;
+
+	/*
+	 * Ensure necessary status bits for deferred errors:
+	 * - MCx_STATUS[Deferred]: make sure it is a deferred error
+	 * - MCx_STATUS[UC] cleared: deferred errors are _not_ UC
+	 */
+	if (inj_type == DFR_INT_INJ) {
+		i_mce.status |= MCI_STATUS_DEFERRED;
+		i_mce.status &= ~MCI_STATUS_UC;
+	}
+
+	/*
+	 * For multi node CPUs, logging and reporting of bank 4 errors happens
+	 * only on the node base core. Refer to D18F3x44[NbMcaToMstCpuEn] for
+	 * Fam10h and later BKDGs.
+	 */
+	if (boot_cpu_has(X86_FEATURE_AMD_DCM) &&
+	    b == 4 &&
+	    boot_cpu_data.x86 < 0x17) {
+		toggle_nb_mca_mst_cpu(topology_die_id(cpu));
+		cpu = get_nbc_for_node(topology_die_id(cpu));
+	}
+
+	cpus_read_lock();
+	if (!cpu_online(cpu))
+		goto err;
+
+	toggle_hw_mce_inject(cpu, true);
+
+	i_mce.mcgstatus = mcg_status;
+	i_mce.inject_flags = inj_type;
+	smp_call_function_single(cpu, prepare_msrs, &i_mce, 0);
+
+	toggle_hw_mce_inject(cpu, false);
+
+	switch (inj_type) {
+	case DFR_INT_INJ:
+		smp_call_function_single(cpu, trigger_dfr_int, NULL, 0);
+		break;
+	case THR_INT_INJ:
+		smp_call_function_single(cpu, trigger_thr_int, NULL, 0);
+		break;
+	default:
+		smp_call_function_single(cpu, trigger_mce, NULL, 0);
+	}
+
+err:
+	cpus_read_unlock();
+
+}
+
+/*
+ * This denotes into which bank we're injecting and triggers
+ * the injection, at the same time.
+ */
+static int inj_bank_set(void *data, u64 val)
+{
+	struct mce *m = (struct mce *)data;
+	u8 n_banks;
+	u64 cap;
+
+	/* Get bank count on target CPU so we can handle non-uniform values. */
+	rdmsrl_on_cpu(m->extcpu, MSR_IA32_MCG_CAP, &cap);
+	n_banks = cap & MCG_BANKCNT_MASK;
+
+	if (val >= n_banks) {
+		pr_err("MCA bank %llu non-existent on CPU%d\n", val, m->extcpu);
+		return -EINVAL;
+	}
+
+	m->bank = val;
+
+	/*
+	 * sw-only injection allows to write arbitrary values into the MCA
+	 * registers because it tests only the decoding paths.
+	 */
+	if (inj_type == SW_INJ)
+		goto inject;
+
+	/*
+	 * Read IPID value to determine if a bank is populated on the target
+	 * CPU.
+	 */
+	if (cpu_feature_enabled(X86_FEATURE_SMCA)) {
+		u64 ipid;
+
+		if (rdmsrl_on_cpu(m->extcpu, MSR_AMD64_SMCA_MCx_IPID(val), &ipid)) {
+			pr_err("Error reading IPID on CPU%d\n", m->extcpu);
+			return -EINVAL;
+		}
+
+		if (!ipid) {
+			pr_err("Cannot inject into unpopulated bank %llu\n", val);
+			return -ENODEV;
+		}
+	}
+
+inject:
+	do_inject();
+
+	/* Reset injection struct */
+	setup_inj_struct(&i_mce);
+
+	return 0;
+}
+
+MCE_INJECT_GET(bank);
+
+DEFINE_SIMPLE_ATTRIBUTE(bank_fops, inj_bank_get, inj_bank_set, "%llu\n");
+
+static const char readme_msg[] =
+"Description of the files and their usages:\n"
+"\n"
+"Note1: i refers to the bank number below.\n"
+"Note2: See respective BKDGs for the exact bit definitions of the files below\n"
+"as they mirror the hardware registers.\n"
+"\n"
+"status:\t Set MCi_STATUS: the bits in that MSR control the error type and\n"
+"\t attributes of the error which caused the MCE.\n"
+"\n"
+"misc:\t Set MCi_MISC: provide auxiliary info about the error. It is mostly\n"
+"\t used for error thresholding purposes and its validity is indicated by\n"
+"\t MCi_STATUS[MiscV].\n"
+"\n"
+"synd:\t Set MCi_SYND: provide syndrome info about the error. Only valid on\n"
+"\t Scalable MCA systems, and its validity is indicated by MCi_STATUS[SyndV].\n"
+"\n"
+"addr:\t Error address value to be written to MCi_ADDR. Log address information\n"
+"\t associated with the error.\n"
+"\n"
+"cpu:\t The CPU to inject the error on.\n"
+"\n"
+"bank:\t Specify the bank you want to inject the error into: the number of\n"
+"\t banks in a processor varies and is family/model-specific, therefore, the\n"
+"\t supplied value is sanity-checked. Setting the bank value also triggers the\n"
+"\t injection.\n"
+"\n"
+"flags:\t Injection type to be performed. Writing to this file will trigger a\n"
+"\t real machine check, an APIC interrupt or invoke the error decoder routines\n"
+"\t for AMD processors.\n"
+"\n"
+"\t Allowed error injection types:\n"
+"\t  - \"sw\": Software error injection. Decode error to a human-readable \n"
+"\t    format only. Safe to use.\n"
+"\t  - \"hw\": Hardware error injection. Causes the #MC exception handler to \n"
+"\t    handle the error. Be warned: might cause system panic if MCi_STATUS[PCC] \n"
+"\t    is set. Therefore, consider setting (debugfs_mountpoint)/mce/fake_panic \n"
+"\t    before injecting.\n"
+"\t  - \"df\": Trigger APIC interrupt for Deferred error. Causes deferred \n"
+"\t    error APIC interrupt handler to handle the error if the feature is \n"
+"\t    is present in hardware. \n"
+"\t  - \"th\": Trigger APIC interrupt for Threshold errors. Causes threshold \n"
+"\t    APIC interrupt handler to handle the error. \n"
+"\n"
+"ipid:\t IPID (AMD-specific)\n"
+"\n";
+
+static ssize_t
+inj_readme_read(struct file *filp, char __user *ubuf,
+		       size_t cnt, loff_t *ppos)
+{
+	return simple_read_from_buffer(ubuf, cnt, ppos,
+					readme_msg, strlen(readme_msg));
+}
+
+static const struct file_operations readme_fops = {
+	.read		= inj_readme_read,
+};
+
+static struct dfs_node {
+	char *name;
+	const struct file_operations *fops;
+	umode_t perm;
+} dfs_fls[] = {
+	{ .name = "status",	.fops = &status_fops, .perm = S_IRUSR | S_IWUSR },
+	{ .name = "misc",	.fops = &misc_fops,   .perm = S_IRUSR | S_IWUSR },
+	{ .name = "addr",	.fops = &addr_fops,   .perm = S_IRUSR | S_IWUSR },
+	{ .name = "synd",	.fops = &synd_fops,   .perm = S_IRUSR | S_IWUSR },
+	{ .name = "ipid",	.fops = &ipid_fops,   .perm = S_IRUSR | S_IWUSR },
+	{ .name = "bank",	.fops = &bank_fops,   .perm = S_IRUSR | S_IWUSR },
+	{ .name = "flags",	.fops = &flags_fops,  .perm = S_IRUSR | S_IWUSR },
+	{ .name = "cpu",	.fops = &extcpu_fops, .perm = S_IRUSR | S_IWUSR },
+	{ .name = "README",	.fops = &readme_fops, .perm = S_IRUSR | S_IRGRP | S_IROTH },
+};
+
+static void __init debugfs_init(void)
+{
+	unsigned int i;
+
+	dfs_inj = debugfs_create_dir("mce-inject", NULL);
+
+	for (i = 0; i < ARRAY_SIZE(dfs_fls); i++)
+		debugfs_create_file(dfs_fls[i].name, dfs_fls[i].perm, dfs_inj,
+				    &i_mce, dfs_fls[i].fops);
+}
+
+static void check_hw_inj_possible(void)
+{
+	int cpu;
+	u8 bank;
+
+	/*
+	 * This behavior exists only on SMCA systems though its not directly
+	 * related to SMCA.
+	 */
+	if (!cpu_feature_enabled(X86_FEATURE_SMCA))
+		return;
+
+	cpu = get_cpu();
+
+	for (bank = 0; bank < MAX_NR_BANKS; ++bank) {
+		u64 status = MCI_STATUS_VAL, ipid;
+
+		/* Check whether bank is populated */
+		rdmsrl(MSR_AMD64_SMCA_MCx_IPID(bank), ipid);
+		if (!ipid)
+			continue;
+
+		toggle_hw_mce_inject(cpu, true);
+
+		wrmsrl_safe(mca_msr_reg(bank, MCA_STATUS), status);
+		rdmsrl_safe(mca_msr_reg(bank, MCA_STATUS), &status);
+		wrmsrl_safe(mca_msr_reg(bank, MCA_STATUS), 0);
+
+		if (!status) {
+			hw_injection_possible = false;
+			pr_warn("Platform does not allow *hardware* error injection."
+				"Try using APEI EINJ instead.\n");
+		}
+
+		toggle_hw_mce_inject(cpu, false);
+
+		break;
+	}
+
+	put_cpu();
+}
+
+static int __init inject_init(void)
+{
+	if (!alloc_cpumask_var(&mce_inject_cpumask, GFP_KERNEL))
+		return -ENOMEM;
+
+	check_hw_inj_possible();
+
+	debugfs_init();
+
+	register_nmi_handler(NMI_LOCAL, mce_raise_notify, 0, "mce_notify");
+	mce_register_injector_chain(&inject_nb);
+
+	setup_inj_struct(&i_mce);
+
+	pr_info("Machine check injector initialized\n");
+
+	return 0;
+}
+
+static void __exit inject_exit(void)
+{
+
+	mce_unregister_injector_chain(&inject_nb);
+	unregister_nmi_handler(NMI_LOCAL, "mce_notify");
+
+	debugfs_remove_recursive(dfs_inj);
+	dfs_inj = NULL;
+
+	memset(&dfs_fls, 0, sizeof(dfs_fls));
+
+	free_cpumask_var(mce_inject_cpumask);
+}
+
+module_init(inject_init);
+module_exit(inject_exit);
+MODULE_LICENSE("GPL");
diff --git a/arch/x86/kernel/cpu/mce/intel.c b/arch/x86/kernel/cpu/mce/intel.c
new file mode 100644
index 0000000000..f5323551c1
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/intel.c
@@ -0,0 +1,538 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel specific MCE features.
+ * Copyright 2004 Zwane Mwaikambo <zwane@linuxpower.ca>
+ * Copyright (C) 2008, 2009 Intel Corporation
+ * Author: Andi Kleen
+ */
+
+#include <linux/gfp.h>
+#include <linux/interrupt.h>
+#include <linux/percpu.h>
+#include <linux/sched.h>
+#include <linux/cpumask.h>
+#include <asm/apic.h>
+#include <asm/cpufeature.h>
+#include <asm/intel-family.h>
+#include <asm/processor.h>
+#include <asm/msr.h>
+#include <asm/mce.h>
+
+#include "internal.h"
+
+/*
+ * Support for Intel Correct Machine Check Interrupts. This allows
+ * the CPU to raise an interrupt when a corrected machine check happened.
+ * Normally we pick those up using a regular polling timer.
+ * Also supports reliable discovery of shared banks.
+ */
+
+/*
+ * CMCI can be delivered to multiple cpus that share a machine check bank
+ * so we need to designate a single cpu to process errors logged in each bank
+ * in the interrupt handler (otherwise we would have many races and potential
+ * double reporting of the same error).
+ * Note that this can change when a cpu is offlined or brought online since
+ * some MCA banks are shared across cpus. When a cpu is offlined, cmci_clear()
+ * disables CMCI on all banks owned by the cpu and clears this bitfield. At
+ * this point, cmci_rediscover() kicks in and a different cpu may end up
+ * taking ownership of some of the shared MCA banks that were previously
+ * owned by the offlined cpu.
+ */
+static DEFINE_PER_CPU(mce_banks_t, mce_banks_owned);
+
+/*
+ * CMCI storm detection backoff counter
+ *
+ * During storm, we reset this counter to INITIAL_CHECK_INTERVAL in case we've
+ * encountered an error. If not, we decrement it by one. We signal the end of
+ * the CMCI storm when it reaches 0.
+ */
+static DEFINE_PER_CPU(int, cmci_backoff_cnt);
+
+/*
+ * cmci_discover_lock protects against parallel discovery attempts
+ * which could race against each other.
+ */
+static DEFINE_RAW_SPINLOCK(cmci_discover_lock);
+
+/*
+ * On systems that do support CMCI but it's disabled, polling for MCEs can
+ * cause the same event to be reported multiple times because IA32_MCi_STATUS
+ * is shared by the same package.
+ */
+static DEFINE_SPINLOCK(cmci_poll_lock);
+
+#define CMCI_THRESHOLD		1
+#define CMCI_POLL_INTERVAL	(30 * HZ)
+#define CMCI_STORM_INTERVAL	(HZ)
+#define CMCI_STORM_THRESHOLD	15
+
+static DEFINE_PER_CPU(unsigned long, cmci_time_stamp);
+static DEFINE_PER_CPU(unsigned int, cmci_storm_cnt);
+static DEFINE_PER_CPU(unsigned int, cmci_storm_state);
+
+enum {
+	CMCI_STORM_NONE,
+	CMCI_STORM_ACTIVE,
+	CMCI_STORM_SUBSIDED,
+};
+
+static atomic_t cmci_storm_on_cpus;
+
+static int cmci_supported(int *banks)
+{
+	u64 cap;
+
+	if (mca_cfg.cmci_disabled || mca_cfg.ignore_ce)
+		return 0;
+
+	/*
+	 * Vendor check is not strictly needed, but the initial
+	 * initialization is vendor keyed and this
+	 * makes sure none of the backdoors are entered otherwise.
+	 */
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL &&
+	    boot_cpu_data.x86_vendor != X86_VENDOR_ZHAOXIN)
+		return 0;
+
+	if (!boot_cpu_has(X86_FEATURE_APIC) || lapic_get_maxlvt() < 6)
+		return 0;
+	rdmsrl(MSR_IA32_MCG_CAP, cap);
+	*banks = min_t(unsigned, MAX_NR_BANKS, cap & 0xff);
+	return !!(cap & MCG_CMCI_P);
+}
+
+static bool lmce_supported(void)
+{
+	u64 tmp;
+
+	if (mca_cfg.lmce_disabled)
+		return false;
+
+	rdmsrl(MSR_IA32_MCG_CAP, tmp);
+
+	/*
+	 * LMCE depends on recovery support in the processor. Hence both
+	 * MCG_SER_P and MCG_LMCE_P should be present in MCG_CAP.
+	 */
+	if ((tmp & (MCG_SER_P | MCG_LMCE_P)) !=
+		   (MCG_SER_P | MCG_LMCE_P))
+		return false;
+
+	/*
+	 * BIOS should indicate support for LMCE by setting bit 20 in
+	 * IA32_FEAT_CTL without which touching MCG_EXT_CTL will generate a #GP
+	 * fault.  The MSR must also be locked for LMCE_ENABLED to take effect.
+	 * WARN if the MSR isn't locked as init_ia32_feat_ctl() unconditionally
+	 * locks the MSR in the event that it wasn't already locked by BIOS.
+	 */
+	rdmsrl(MSR_IA32_FEAT_CTL, tmp);
+	if (WARN_ON_ONCE(!(tmp & FEAT_CTL_LOCKED)))
+		return false;
+
+	return tmp & FEAT_CTL_LMCE_ENABLED;
+}
+
+bool mce_intel_cmci_poll(void)
+{
+	if (__this_cpu_read(cmci_storm_state) == CMCI_STORM_NONE)
+		return false;
+
+	/*
+	 * Reset the counter if we've logged an error in the last poll
+	 * during the storm.
+	 */
+	if (machine_check_poll(0, this_cpu_ptr(&mce_banks_owned)))
+		this_cpu_write(cmci_backoff_cnt, INITIAL_CHECK_INTERVAL);
+	else
+		this_cpu_dec(cmci_backoff_cnt);
+
+	return true;
+}
+
+void mce_intel_hcpu_update(unsigned long cpu)
+{
+	if (per_cpu(cmci_storm_state, cpu) == CMCI_STORM_ACTIVE)
+		atomic_dec(&cmci_storm_on_cpus);
+
+	per_cpu(cmci_storm_state, cpu) = CMCI_STORM_NONE;
+}
+
+static void cmci_toggle_interrupt_mode(bool on)
+{
+	unsigned long flags, *owned;
+	int bank;
+	u64 val;
+
+	raw_spin_lock_irqsave(&cmci_discover_lock, flags);
+	owned = this_cpu_ptr(mce_banks_owned);
+	for_each_set_bit(bank, owned, MAX_NR_BANKS) {
+		rdmsrl(MSR_IA32_MCx_CTL2(bank), val);
+
+		if (on)
+			val |= MCI_CTL2_CMCI_EN;
+		else
+			val &= ~MCI_CTL2_CMCI_EN;
+
+		wrmsrl(MSR_IA32_MCx_CTL2(bank), val);
+	}
+	raw_spin_unlock_irqrestore(&cmci_discover_lock, flags);
+}
+
+unsigned long cmci_intel_adjust_timer(unsigned long interval)
+{
+	if ((this_cpu_read(cmci_backoff_cnt) > 0) &&
+	    (__this_cpu_read(cmci_storm_state) == CMCI_STORM_ACTIVE)) {
+		mce_notify_irq();
+		return CMCI_STORM_INTERVAL;
+	}
+
+	switch (__this_cpu_read(cmci_storm_state)) {
+	case CMCI_STORM_ACTIVE:
+
+		/*
+		 * We switch back to interrupt mode once the poll timer has
+		 * silenced itself. That means no events recorded and the timer
+		 * interval is back to our poll interval.
+		 */
+		__this_cpu_write(cmci_storm_state, CMCI_STORM_SUBSIDED);
+		if (!atomic_sub_return(1, &cmci_storm_on_cpus))
+			pr_notice("CMCI storm subsided: switching to interrupt mode\n");
+
+		fallthrough;
+
+	case CMCI_STORM_SUBSIDED:
+		/*
+		 * We wait for all CPUs to go back to SUBSIDED state. When that
+		 * happens we switch back to interrupt mode.
+		 */
+		if (!atomic_read(&cmci_storm_on_cpus)) {
+			__this_cpu_write(cmci_storm_state, CMCI_STORM_NONE);
+			cmci_toggle_interrupt_mode(true);
+			cmci_recheck();
+		}
+		return CMCI_POLL_INTERVAL;
+	default:
+
+		/* We have shiny weather. Let the poll do whatever it thinks. */
+		return interval;
+	}
+}
+
+static bool cmci_storm_detect(void)
+{
+	unsigned int cnt = __this_cpu_read(cmci_storm_cnt);
+	unsigned long ts = __this_cpu_read(cmci_time_stamp);
+	unsigned long now = jiffies;
+	int r;
+
+	if (__this_cpu_read(cmci_storm_state) != CMCI_STORM_NONE)
+		return true;
+
+	if (time_before_eq(now, ts + CMCI_STORM_INTERVAL)) {
+		cnt++;
+	} else {
+		cnt = 1;
+		__this_cpu_write(cmci_time_stamp, now);
+	}
+	__this_cpu_write(cmci_storm_cnt, cnt);
+
+	if (cnt <= CMCI_STORM_THRESHOLD)
+		return false;
+
+	cmci_toggle_interrupt_mode(false);
+	__this_cpu_write(cmci_storm_state, CMCI_STORM_ACTIVE);
+	r = atomic_add_return(1, &cmci_storm_on_cpus);
+	mce_timer_kick(CMCI_STORM_INTERVAL);
+	this_cpu_write(cmci_backoff_cnt, INITIAL_CHECK_INTERVAL);
+
+	if (r == 1)
+		pr_notice("CMCI storm detected: switching to poll mode\n");
+	return true;
+}
+
+/*
+ * The interrupt handler. This is called on every event.
+ * Just call the poller directly to log any events.
+ * This could in theory increase the threshold under high load,
+ * but doesn't for now.
+ */
+static void intel_threshold_interrupt(void)
+{
+	if (cmci_storm_detect())
+		return;
+
+	machine_check_poll(MCP_TIMESTAMP, this_cpu_ptr(&mce_banks_owned));
+}
+
+/*
+ * Enable CMCI (Corrected Machine Check Interrupt) for available MCE banks
+ * on this CPU. Use the algorithm recommended in the SDM to discover shared
+ * banks.
+ */
+static void cmci_discover(int banks)
+{
+	unsigned long *owned = (void *)this_cpu_ptr(&mce_banks_owned);
+	unsigned long flags;
+	int i;
+	int bios_wrong_thresh = 0;
+
+	raw_spin_lock_irqsave(&cmci_discover_lock, flags);
+	for (i = 0; i < banks; i++) {
+		u64 val;
+		int bios_zero_thresh = 0;
+
+		if (test_bit(i, owned))
+			continue;
+
+		/* Skip banks in firmware first mode */
+		if (test_bit(i, mce_banks_ce_disabled))
+			continue;
+
+		rdmsrl(MSR_IA32_MCx_CTL2(i), val);
+
+		/* Already owned by someone else? */
+		if (val & MCI_CTL2_CMCI_EN) {
+			clear_bit(i, owned);
+			__clear_bit(i, this_cpu_ptr(mce_poll_banks));
+			continue;
+		}
+
+		if (!mca_cfg.bios_cmci_threshold) {
+			val &= ~MCI_CTL2_CMCI_THRESHOLD_MASK;
+			val |= CMCI_THRESHOLD;
+		} else if (!(val & MCI_CTL2_CMCI_THRESHOLD_MASK)) {
+			/*
+			 * If bios_cmci_threshold boot option was specified
+			 * but the threshold is zero, we'll try to initialize
+			 * it to 1.
+			 */
+			bios_zero_thresh = 1;
+			val |= CMCI_THRESHOLD;
+		}
+
+		val |= MCI_CTL2_CMCI_EN;
+		wrmsrl(MSR_IA32_MCx_CTL2(i), val);
+		rdmsrl(MSR_IA32_MCx_CTL2(i), val);
+
+		/* Did the enable bit stick? -- the bank supports CMCI */
+		if (val & MCI_CTL2_CMCI_EN) {
+			set_bit(i, owned);
+			__clear_bit(i, this_cpu_ptr(mce_poll_banks));
+			/*
+			 * We are able to set thresholds for some banks that
+			 * had a threshold of 0. This means the BIOS has not
+			 * set the thresholds properly or does not work with
+			 * this boot option. Note down now and report later.
+			 */
+			if (mca_cfg.bios_cmci_threshold && bios_zero_thresh &&
+					(val & MCI_CTL2_CMCI_THRESHOLD_MASK))
+				bios_wrong_thresh = 1;
+		} else {
+			WARN_ON(!test_bit(i, this_cpu_ptr(mce_poll_banks)));
+		}
+	}
+	raw_spin_unlock_irqrestore(&cmci_discover_lock, flags);
+	if (mca_cfg.bios_cmci_threshold && bios_wrong_thresh) {
+		pr_info_once(
+			"bios_cmci_threshold: Some banks do not have valid thresholds set\n");
+		pr_info_once(
+			"bios_cmci_threshold: Make sure your BIOS supports this boot option\n");
+	}
+}
+
+/*
+ * Just in case we missed an event during initialization check
+ * all the CMCI owned banks.
+ */
+void cmci_recheck(void)
+{
+	unsigned long flags;
+	int banks;
+
+	if (!mce_available(raw_cpu_ptr(&cpu_info)) || !cmci_supported(&banks))
+		return;
+
+	local_irq_save(flags);
+	machine_check_poll(0, this_cpu_ptr(&mce_banks_owned));
+	local_irq_restore(flags);
+}
+
+/* Caller must hold the lock on cmci_discover_lock */
+static void __cmci_disable_bank(int bank)
+{
+	u64 val;
+
+	if (!test_bit(bank, this_cpu_ptr(mce_banks_owned)))
+		return;
+	rdmsrl(MSR_IA32_MCx_CTL2(bank), val);
+	val &= ~MCI_CTL2_CMCI_EN;
+	wrmsrl(MSR_IA32_MCx_CTL2(bank), val);
+	__clear_bit(bank, this_cpu_ptr(mce_banks_owned));
+}
+
+/*
+ * Disable CMCI on this CPU for all banks it owns when it goes down.
+ * This allows other CPUs to claim the banks on rediscovery.
+ */
+void cmci_clear(void)
+{
+	unsigned long flags;
+	int i;
+	int banks;
+
+	if (!cmci_supported(&banks))
+		return;
+	raw_spin_lock_irqsave(&cmci_discover_lock, flags);
+	for (i = 0; i < banks; i++)
+		__cmci_disable_bank(i);
+	raw_spin_unlock_irqrestore(&cmci_discover_lock, flags);
+}
+
+static void cmci_rediscover_work_func(void *arg)
+{
+	int banks;
+
+	/* Recheck banks in case CPUs don't all have the same */
+	if (cmci_supported(&banks))
+		cmci_discover(banks);
+}
+
+/* After a CPU went down cycle through all the others and rediscover */
+void cmci_rediscover(void)
+{
+	int banks;
+
+	if (!cmci_supported(&banks))
+		return;
+
+	on_each_cpu(cmci_rediscover_work_func, NULL, 1);
+}
+
+/*
+ * Reenable CMCI on this CPU in case a CPU down failed.
+ */
+void cmci_reenable(void)
+{
+	int banks;
+	if (cmci_supported(&banks))
+		cmci_discover(banks);
+}
+
+void cmci_disable_bank(int bank)
+{
+	int banks;
+	unsigned long flags;
+
+	if (!cmci_supported(&banks))
+		return;
+
+	raw_spin_lock_irqsave(&cmci_discover_lock, flags);
+	__cmci_disable_bank(bank);
+	raw_spin_unlock_irqrestore(&cmci_discover_lock, flags);
+}
+
+/* Bank polling function when CMCI is disabled. */
+static void cmci_mc_poll_banks(void)
+{
+	spin_lock(&cmci_poll_lock);
+	machine_check_poll(0, this_cpu_ptr(&mce_poll_banks));
+	spin_unlock(&cmci_poll_lock);
+}
+
+void intel_init_cmci(void)
+{
+	int banks;
+
+	if (!cmci_supported(&banks)) {
+		mc_poll_banks = cmci_mc_poll_banks;
+		return;
+	}
+
+	mce_threshold_vector = intel_threshold_interrupt;
+	cmci_discover(banks);
+	/*
+	 * For CPU #0 this runs with still disabled APIC, but that's
+	 * ok because only the vector is set up. We still do another
+	 * check for the banks later for CPU #0 just to make sure
+	 * to not miss any events.
+	 */
+	apic_write(APIC_LVTCMCI, THRESHOLD_APIC_VECTOR|APIC_DM_FIXED);
+	cmci_recheck();
+}
+
+void intel_init_lmce(void)
+{
+	u64 val;
+
+	if (!lmce_supported())
+		return;
+
+	rdmsrl(MSR_IA32_MCG_EXT_CTL, val);
+
+	if (!(val & MCG_EXT_CTL_LMCE_EN))
+		wrmsrl(MSR_IA32_MCG_EXT_CTL, val | MCG_EXT_CTL_LMCE_EN);
+}
+
+void intel_clear_lmce(void)
+{
+	u64 val;
+
+	if (!lmce_supported())
+		return;
+
+	rdmsrl(MSR_IA32_MCG_EXT_CTL, val);
+	val &= ~MCG_EXT_CTL_LMCE_EN;
+	wrmsrl(MSR_IA32_MCG_EXT_CTL, val);
+}
+
+/*
+ * Enable additional error logs from the integrated
+ * memory controller on processors that support this.
+ */
+static void intel_imc_init(struct cpuinfo_x86 *c)
+{
+	u64 error_control;
+
+	switch (c->x86_model) {
+	case INTEL_FAM6_SANDYBRIDGE_X:
+	case INTEL_FAM6_IVYBRIDGE_X:
+	case INTEL_FAM6_HASWELL_X:
+		if (rdmsrl_safe(MSR_ERROR_CONTROL, &error_control))
+			return;
+		error_control |= 2;
+		wrmsrl_safe(MSR_ERROR_CONTROL, error_control);
+		break;
+	}
+}
+
+void mce_intel_feature_init(struct cpuinfo_x86 *c)
+{
+	intel_init_cmci();
+	intel_init_lmce();
+	intel_imc_init(c);
+}
+
+void mce_intel_feature_clear(struct cpuinfo_x86 *c)
+{
+	intel_clear_lmce();
+}
+
+bool intel_filter_mce(struct mce *m)
+{
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+
+	/* MCE errata HSD131, HSM142, HSW131, BDM48, HSM142 and SKX37 */
+	if ((c->x86 == 6) &&
+	    ((c->x86_model == INTEL_FAM6_HASWELL) ||
+	     (c->x86_model == INTEL_FAM6_HASWELL_L) ||
+	     (c->x86_model == INTEL_FAM6_BROADWELL) ||
+	     (c->x86_model == INTEL_FAM6_HASWELL_G) ||
+	     (c->x86_model == INTEL_FAM6_SKYLAKE_X)) &&
+	    (m->bank == 0) &&
+	    ((m->status & 0xa0000000ffffffff) == 0x80000000000f0005))
+		return true;
+
+	return false;
+}
diff --git a/arch/x86/kernel/cpu/mce/internal.h b/arch/x86/kernel/cpu/mce/internal.h
new file mode 100644
index 0000000000..bcf1b3c66c
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/internal.h
@@ -0,0 +1,281 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __X86_MCE_INTERNAL_H__
+#define __X86_MCE_INTERNAL_H__
+
+#undef pr_fmt
+#define pr_fmt(fmt) "mce: " fmt
+
+#include <linux/device.h>
+#include <asm/mce.h>
+
+enum severity_level {
+	MCE_NO_SEVERITY,
+	MCE_DEFERRED_SEVERITY,
+	MCE_UCNA_SEVERITY = MCE_DEFERRED_SEVERITY,
+	MCE_KEEP_SEVERITY,
+	MCE_SOME_SEVERITY,
+	MCE_AO_SEVERITY,
+	MCE_UC_SEVERITY,
+	MCE_AR_SEVERITY,
+	MCE_PANIC_SEVERITY,
+};
+
+extern struct blocking_notifier_head x86_mce_decoder_chain;
+
+#define INITIAL_CHECK_INTERVAL	5 * 60 /* 5 minutes */
+
+struct mce_evt_llist {
+	struct llist_node llnode;
+	struct mce mce;
+};
+
+void mce_gen_pool_process(struct work_struct *__unused);
+bool mce_gen_pool_empty(void);
+int mce_gen_pool_add(struct mce *mce);
+int mce_gen_pool_init(void);
+struct llist_node *mce_gen_pool_prepare_records(void);
+
+int mce_severity(struct mce *a, struct pt_regs *regs, char **msg, bool is_excp);
+struct dentry *mce_get_debugfs_dir(void);
+
+extern mce_banks_t mce_banks_ce_disabled;
+
+#ifdef CONFIG_X86_MCE_INTEL
+unsigned long cmci_intel_adjust_timer(unsigned long interval);
+bool mce_intel_cmci_poll(void);
+void mce_intel_hcpu_update(unsigned long cpu);
+void cmci_disable_bank(int bank);
+void intel_init_cmci(void);
+void intel_init_lmce(void);
+void intel_clear_lmce(void);
+bool intel_filter_mce(struct mce *m);
+#else
+# define cmci_intel_adjust_timer mce_adjust_timer_default
+static inline bool mce_intel_cmci_poll(void) { return false; }
+static inline void mce_intel_hcpu_update(unsigned long cpu) { }
+static inline void cmci_disable_bank(int bank) { }
+static inline void intel_init_cmci(void) { }
+static inline void intel_init_lmce(void) { }
+static inline void intel_clear_lmce(void) { }
+static inline bool intel_filter_mce(struct mce *m) { return false; }
+#endif
+
+void mce_timer_kick(unsigned long interval);
+
+#ifdef CONFIG_ACPI_APEI
+int apei_write_mce(struct mce *m);
+ssize_t apei_read_mce(struct mce *m, u64 *record_id);
+int apei_check_mce(void);
+int apei_clear_mce(u64 record_id);
+#else
+static inline int apei_write_mce(struct mce *m)
+{
+	return -EINVAL;
+}
+static inline ssize_t apei_read_mce(struct mce *m, u64 *record_id)
+{
+	return 0;
+}
+static inline int apei_check_mce(void)
+{
+	return 0;
+}
+static inline int apei_clear_mce(u64 record_id)
+{
+	return -EINVAL;
+}
+#endif
+
+/*
+ * We consider records to be equivalent if bank+status+addr+misc all match.
+ * This is only used when the system is going down because of a fatal error
+ * to avoid cluttering the console log with essentially repeated information.
+ * In normal processing all errors seen are logged.
+ */
+static inline bool mce_cmp(struct mce *m1, struct mce *m2)
+{
+	return m1->bank != m2->bank ||
+		m1->status != m2->status ||
+		m1->addr != m2->addr ||
+		m1->misc != m2->misc;
+}
+
+extern struct device_attribute dev_attr_trigger;
+
+#ifdef CONFIG_X86_MCELOG_LEGACY
+void mce_work_trigger(void);
+void mce_register_injector_chain(struct notifier_block *nb);
+void mce_unregister_injector_chain(struct notifier_block *nb);
+#else
+static inline void mce_work_trigger(void)	{ }
+static inline void mce_register_injector_chain(struct notifier_block *nb)	{ }
+static inline void mce_unregister_injector_chain(struct notifier_block *nb)	{ }
+#endif
+
+struct mca_config {
+	__u64 lmce_disabled		: 1,
+	      disabled			: 1,
+	      ser			: 1,
+	      recovery			: 1,
+	      bios_cmci_threshold	: 1,
+	      /* Proper #MC exception handler is set */
+	      initialized		: 1,
+	      __reserved		: 58;
+
+	bool dont_log_ce;
+	bool cmci_disabled;
+	bool ignore_ce;
+	bool print_all;
+
+	int monarch_timeout;
+	int panic_timeout;
+	u32 rip_msr;
+	s8 bootlog;
+};
+
+extern struct mca_config mca_cfg;
+DECLARE_PER_CPU_READ_MOSTLY(unsigned int, mce_num_banks);
+
+struct mce_vendor_flags {
+	/*
+	 * Indicates that overflow conditions are not fatal, when set.
+	 */
+	__u64 overflow_recov	: 1,
+
+	/*
+	 * (AMD) SUCCOR stands for S/W UnCorrectable error COntainment and
+	 * Recovery. It indicates support for data poisoning in HW and deferred
+	 * error interrupts.
+	 */
+	succor			: 1,
+
+	/*
+	 * (AMD) SMCA: This bit indicates support for Scalable MCA which expands
+	 * the register space for each MCA bank and also increases number of
+	 * banks. Also, to accommodate the new banks and registers, the MCA
+	 * register space is moved to a new MSR range.
+	 */
+	smca			: 1,
+
+	/* Zen IFU quirk */
+	zen_ifu_quirk		: 1,
+
+	/* AMD-style error thresholding banks present. */
+	amd_threshold		: 1,
+
+	/* Pentium, family 5-style MCA */
+	p5			: 1,
+
+	/* Centaur Winchip C6-style MCA */
+	winchip			: 1,
+
+	/* SandyBridge IFU quirk */
+	snb_ifu_quirk		: 1,
+
+	/* Skylake, Cascade Lake, Cooper Lake REP;MOVS* quirk */
+	skx_repmov_quirk	: 1,
+
+	__reserved_0		: 55;
+};
+
+extern struct mce_vendor_flags mce_flags;
+
+struct mce_bank {
+	/* subevents to enable */
+	u64			ctl;
+
+	/* initialise bank? */
+	__u64 init		: 1,
+
+	/*
+	 * (AMD) MCA_CONFIG[McaLsbInStatusSupported]: When set, this bit indicates
+	 * the LSB field is found in MCA_STATUS and not in MCA_ADDR.
+	 */
+	lsb_in_status		: 1,
+
+	__reserved_1		: 62;
+};
+
+DECLARE_PER_CPU_READ_MOSTLY(struct mce_bank[MAX_NR_BANKS], mce_banks_array);
+
+enum mca_msr {
+	MCA_CTL,
+	MCA_STATUS,
+	MCA_ADDR,
+	MCA_MISC,
+};
+
+/* Decide whether to add MCE record to MCE event pool or filter it out. */
+extern bool filter_mce(struct mce *m);
+
+#ifdef CONFIG_X86_MCE_AMD
+extern bool amd_filter_mce(struct mce *m);
+
+/*
+ * If MCA_CONFIG[McaLsbInStatusSupported] is set, extract ErrAddr in bits
+ * [56:0] of MCA_STATUS, else in bits [55:0] of MCA_ADDR.
+ */
+static __always_inline void smca_extract_err_addr(struct mce *m)
+{
+	u8 lsb;
+
+	if (!mce_flags.smca)
+		return;
+
+	if (this_cpu_ptr(mce_banks_array)[m->bank].lsb_in_status) {
+		lsb = (m->status >> 24) & 0x3f;
+
+		m->addr &= GENMASK_ULL(56, lsb);
+
+		return;
+	}
+
+	lsb = (m->addr >> 56) & 0x3f;
+
+	m->addr &= GENMASK_ULL(55, lsb);
+}
+
+#else
+static inline bool amd_filter_mce(struct mce *m) { return false; }
+static inline void smca_extract_err_addr(struct mce *m) { }
+#endif
+
+#ifdef CONFIG_X86_ANCIENT_MCE
+void intel_p5_mcheck_init(struct cpuinfo_x86 *c);
+void winchip_mcheck_init(struct cpuinfo_x86 *c);
+noinstr void pentium_machine_check(struct pt_regs *regs);
+noinstr void winchip_machine_check(struct pt_regs *regs);
+static inline void enable_p5_mce(void) { mce_p5_enabled = 1; }
+#else
+static __always_inline void intel_p5_mcheck_init(struct cpuinfo_x86 *c) {}
+static __always_inline void winchip_mcheck_init(struct cpuinfo_x86 *c) {}
+static __always_inline void enable_p5_mce(void) {}
+static __always_inline void pentium_machine_check(struct pt_regs *regs) {}
+static __always_inline void winchip_machine_check(struct pt_regs *regs) {}
+#endif
+
+noinstr u64 mce_rdmsrl(u32 msr);
+
+static __always_inline u32 mca_msr_reg(int bank, enum mca_msr reg)
+{
+	if (cpu_feature_enabled(X86_FEATURE_SMCA)) {
+		switch (reg) {
+		case MCA_CTL:	 return MSR_AMD64_SMCA_MCx_CTL(bank);
+		case MCA_ADDR:	 return MSR_AMD64_SMCA_MCx_ADDR(bank);
+		case MCA_MISC:	 return MSR_AMD64_SMCA_MCx_MISC(bank);
+		case MCA_STATUS: return MSR_AMD64_SMCA_MCx_STATUS(bank);
+		}
+	}
+
+	switch (reg) {
+	case MCA_CTL:	 return MSR_IA32_MCx_CTL(bank);
+	case MCA_ADDR:	 return MSR_IA32_MCx_ADDR(bank);
+	case MCA_MISC:	 return MSR_IA32_MCx_MISC(bank);
+	case MCA_STATUS: return MSR_IA32_MCx_STATUS(bank);
+	}
+
+	return 0;
+}
+
+extern void (*mc_poll_banks)(void);
+#endif /* __X86_MCE_INTERNAL_H__ */
diff --git a/arch/x86/kernel/cpu/mce/p5.c b/arch/x86/kernel/cpu/mce/p5.c
new file mode 100644
index 0000000000..2272ad53fc
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/p5.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * P5 specific Machine Check Exception Reporting
+ * (C) Copyright 2002 Alan Cox <alan@lxorguk.ukuu.org.uk>
+ */
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/smp.h>
+#include <linux/hardirq.h>
+
+#include <asm/processor.h>
+#include <asm/traps.h>
+#include <asm/tlbflush.h>
+#include <asm/mce.h>
+#include <asm/msr.h>
+
+#include "internal.h"
+
+/* By default disabled */
+int mce_p5_enabled __read_mostly;
+
+/* Machine check handler for Pentium class Intel CPUs: */
+noinstr void pentium_machine_check(struct pt_regs *regs)
+{
+	u32 loaddr, hi, lotype;
+
+	instrumentation_begin();
+	rdmsr(MSR_IA32_P5_MC_ADDR, loaddr, hi);
+	rdmsr(MSR_IA32_P5_MC_TYPE, lotype, hi);
+
+	pr_emerg("CPU#%d: Machine Check Exception:  0x%8X (type 0x%8X).\n",
+		 smp_processor_id(), loaddr, lotype);
+
+	if (lotype & (1<<5)) {
+		pr_emerg("CPU#%d: Possible thermal failure (CPU on fire ?).\n",
+			 smp_processor_id());
+	}
+
+	add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE);
+	instrumentation_end();
+}
+
+/* Set up machine check reporting for processors with Intel style MCE: */
+void intel_p5_mcheck_init(struct cpuinfo_x86 *c)
+{
+	u32 l, h;
+
+	/* Default P5 to off as its often misconnected: */
+	if (!mce_p5_enabled)
+		return;
+
+	/* Check for MCE support: */
+	if (!cpu_has(c, X86_FEATURE_MCE))
+		return;
+
+	/* Read registers before enabling: */
+	rdmsr(MSR_IA32_P5_MC_ADDR, l, h);
+	rdmsr(MSR_IA32_P5_MC_TYPE, l, h);
+	pr_info("Intel old style machine check architecture supported.\n");
+
+	/* Enable MCE: */
+	cr4_set_bits(X86_CR4_MCE);
+	pr_info("Intel old style machine check reporting enabled on CPU#%d.\n",
+		smp_processor_id());
+}
diff --git a/arch/x86/kernel/cpu/mce/severity.c b/arch/x86/kernel/cpu/mce/severity.c
new file mode 100644
index 0000000000..c4477162c0
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/severity.c
@@ -0,0 +1,479 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * MCE grading rules.
+ * Copyright 2008, 2009 Intel Corporation.
+ *
+ * Author: Andi Kleen
+ */
+#include <linux/kernel.h>
+#include <linux/seq_file.h>
+#include <linux/init.h>
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
+
+#include <asm/mce.h>
+#include <asm/intel-family.h>
+#include <asm/traps.h>
+#include <asm/insn.h>
+#include <asm/insn-eval.h>
+
+#include "internal.h"
+
+/*
+ * Grade an mce by severity. In general the most severe ones are processed
+ * first. Since there are quite a lot of combinations test the bits in a
+ * table-driven way. The rules are simply processed in order, first
+ * match wins.
+ *
+ * Note this is only used for machine check exceptions, the corrected
+ * errors use much simpler rules. The exceptions still check for the corrected
+ * errors, but only to leave them alone for the CMCI handler (except for
+ * panic situations)
+ */
+
+enum context { IN_KERNEL = 1, IN_USER = 2, IN_KERNEL_RECOV = 3 };
+enum ser { SER_REQUIRED = 1, NO_SER = 2 };
+enum exception { EXCP_CONTEXT = 1, NO_EXCP = 2 };
+
+static struct severity {
+	u64 mask;
+	u64 result;
+	unsigned char sev;
+	unsigned char mcgmask;
+	unsigned char mcgres;
+	unsigned char ser;
+	unsigned char context;
+	unsigned char excp;
+	unsigned char covered;
+	unsigned char cpu_model;
+	unsigned char cpu_minstepping;
+	unsigned char bank_lo, bank_hi;
+	char *msg;
+} severities[] = {
+#define MCESEV(s, m, c...) { .sev = MCE_ ## s ## _SEVERITY, .msg = m, ## c }
+#define BANK_RANGE(l, h) .bank_lo = l, .bank_hi = h
+#define MODEL_STEPPING(m, s) .cpu_model = m, .cpu_minstepping = s
+#define  KERNEL		.context = IN_KERNEL
+#define  USER		.context = IN_USER
+#define  KERNEL_RECOV	.context = IN_KERNEL_RECOV
+#define  SER		.ser = SER_REQUIRED
+#define  NOSER		.ser = NO_SER
+#define  EXCP		.excp = EXCP_CONTEXT
+#define  NOEXCP		.excp = NO_EXCP
+#define  BITCLR(x)	.mask = x, .result = 0
+#define  BITSET(x)	.mask = x, .result = x
+#define  MCGMASK(x, y)	.mcgmask = x, .mcgres = y
+#define  MASK(x, y)	.mask = x, .result = y
+#define MCI_UC_S (MCI_STATUS_UC|MCI_STATUS_S)
+#define MCI_UC_AR (MCI_STATUS_UC|MCI_STATUS_AR)
+#define MCI_UC_SAR (MCI_STATUS_UC|MCI_STATUS_S|MCI_STATUS_AR)
+#define	MCI_ADDR (MCI_STATUS_ADDRV|MCI_STATUS_MISCV)
+
+	MCESEV(
+		NO, "Invalid",
+		BITCLR(MCI_STATUS_VAL)
+		),
+	MCESEV(
+		NO, "Not enabled",
+		EXCP, BITCLR(MCI_STATUS_EN)
+		),
+	MCESEV(
+		PANIC, "Processor context corrupt",
+		BITSET(MCI_STATUS_PCC)
+		),
+	/* When MCIP is not set something is very confused */
+	MCESEV(
+		PANIC, "MCIP not set in MCA handler",
+		EXCP, MCGMASK(MCG_STATUS_MCIP, 0)
+		),
+	/* Neither return not error IP -- no chance to recover -> PANIC */
+	MCESEV(
+		PANIC, "Neither restart nor error IP",
+		EXCP, MCGMASK(MCG_STATUS_RIPV|MCG_STATUS_EIPV, 0)
+		),
+	MCESEV(
+		PANIC, "In kernel and no restart IP",
+		EXCP, KERNEL, MCGMASK(MCG_STATUS_RIPV, 0)
+		),
+	MCESEV(
+		PANIC, "In kernel and no restart IP",
+		EXCP, KERNEL_RECOV, MCGMASK(MCG_STATUS_RIPV, 0)
+		),
+	MCESEV(
+		KEEP, "Corrected error",
+		NOSER, BITCLR(MCI_STATUS_UC)
+		),
+	/*
+	 * known AO MCACODs reported via MCE or CMC:
+	 *
+	 * SRAO could be signaled either via a machine check exception or
+	 * CMCI with the corresponding bit S 1 or 0. So we don't need to
+	 * check bit S for SRAO.
+	 */
+	MCESEV(
+		AO, "Action optional: memory scrubbing error",
+		SER, MASK(MCI_UC_AR|MCACOD_SCRUBMSK, MCI_STATUS_UC|MCACOD_SCRUB)
+		),
+	MCESEV(
+		AO, "Action optional: last level cache writeback error",
+		SER, MASK(MCI_UC_AR|MCACOD, MCI_STATUS_UC|MCACOD_L3WB)
+		),
+	/*
+	 * Quirk for Skylake/Cascade Lake. Patrol scrubber may be configured
+	 * to report uncorrected errors using CMCI with a special signature.
+	 * UC=0, MSCOD=0x0010, MCACOD=binary(000X 0000 1100 XXXX) reported
+	 * in one of the memory controller banks.
+	 * Set severity to "AO" for same action as normal patrol scrub error.
+	 */
+	MCESEV(
+		AO, "Uncorrected Patrol Scrub Error",
+		SER, MASK(MCI_STATUS_UC|MCI_ADDR|0xffffeff0, MCI_ADDR|0x001000c0),
+		MODEL_STEPPING(INTEL_FAM6_SKYLAKE_X, 4), BANK_RANGE(13, 18)
+	),
+
+	/* ignore OVER for UCNA */
+	MCESEV(
+		UCNA, "Uncorrected no action required",
+		SER, MASK(MCI_UC_SAR, MCI_STATUS_UC)
+		),
+	MCESEV(
+		PANIC, "Illegal combination (UCNA with AR=1)",
+		SER,
+		MASK(MCI_STATUS_OVER|MCI_UC_SAR, MCI_STATUS_UC|MCI_STATUS_AR)
+		),
+	MCESEV(
+		KEEP, "Non signaled machine check",
+		SER, BITCLR(MCI_STATUS_S)
+		),
+
+	MCESEV(
+		PANIC, "Action required with lost events",
+		SER, BITSET(MCI_STATUS_OVER|MCI_UC_SAR)
+		),
+
+	/* known AR MCACODs: */
+#ifdef	CONFIG_MEMORY_FAILURE
+	MCESEV(
+		KEEP, "Action required but unaffected thread is continuable",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCI_ADDR, MCI_UC_SAR|MCI_ADDR),
+		MCGMASK(MCG_STATUS_RIPV|MCG_STATUS_EIPV, MCG_STATUS_RIPV)
+		),
+	MCESEV(
+		AR, "Action required: data load in error recoverable area of kernel",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCI_ADDR|MCACOD, MCI_UC_SAR|MCI_ADDR|MCACOD_DATA),
+		KERNEL_RECOV
+		),
+	MCESEV(
+		AR, "Action required: data load error in a user process",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCI_ADDR|MCACOD, MCI_UC_SAR|MCI_ADDR|MCACOD_DATA),
+		USER
+		),
+	MCESEV(
+		AR, "Action required: instruction fetch error in a user process",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCI_ADDR|MCACOD, MCI_UC_SAR|MCI_ADDR|MCACOD_INSTR),
+		USER
+		),
+	MCESEV(
+		PANIC, "Data load in unrecoverable area of kernel",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCI_ADDR|MCACOD, MCI_UC_SAR|MCI_ADDR|MCACOD_DATA),
+		KERNEL
+		),
+	MCESEV(
+		PANIC, "Instruction fetch error in kernel",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCI_ADDR|MCACOD, MCI_UC_SAR|MCI_ADDR|MCACOD_INSTR),
+		KERNEL
+		),
+#endif
+	MCESEV(
+		PANIC, "Action required: unknown MCACOD",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR, MCI_UC_SAR)
+		),
+
+	MCESEV(
+		SOME, "Action optional: unknown MCACOD",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR, MCI_UC_S)
+		),
+	MCESEV(
+		SOME, "Action optional with lost events",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR, MCI_STATUS_OVER|MCI_UC_S)
+		),
+
+	MCESEV(
+		PANIC, "Overflowed uncorrected",
+		BITSET(MCI_STATUS_OVER|MCI_STATUS_UC)
+		),
+	MCESEV(
+		PANIC, "Uncorrected in kernel",
+		BITSET(MCI_STATUS_UC),
+		KERNEL
+		),
+	MCESEV(
+		UC, "Uncorrected",
+		BITSET(MCI_STATUS_UC)
+		),
+	MCESEV(
+		SOME, "No match",
+		BITSET(0)
+		)	/* always matches. keep at end */
+};
+
+#define mc_recoverable(mcg) (((mcg) & (MCG_STATUS_RIPV|MCG_STATUS_EIPV)) == \
+				(MCG_STATUS_RIPV|MCG_STATUS_EIPV))
+
+static bool is_copy_from_user(struct pt_regs *regs)
+{
+	u8 insn_buf[MAX_INSN_SIZE];
+	unsigned long addr;
+	struct insn insn;
+	int ret;
+
+	if (!regs)
+		return false;
+
+	if (copy_from_kernel_nofault(insn_buf, (void *)regs->ip, MAX_INSN_SIZE))
+		return false;
+
+	ret = insn_decode_kernel(&insn, insn_buf);
+	if (ret < 0)
+		return false;
+
+	switch (insn.opcode.value) {
+	/* MOV mem,reg */
+	case 0x8A: case 0x8B:
+	/* MOVZ mem,reg */
+	case 0xB60F: case 0xB70F:
+		addr = (unsigned long)insn_get_addr_ref(&insn, regs);
+		break;
+	/* REP MOVS */
+	case 0xA4: case 0xA5:
+		addr = regs->si;
+		break;
+	default:
+		return false;
+	}
+
+	if (fault_in_kernel_space(addr))
+		return false;
+
+	current->mce_vaddr = (void __user *)addr;
+
+	return true;
+}
+
+/*
+ * If mcgstatus indicated that ip/cs on the stack were
+ * no good, then "m->cs" will be zero and we will have
+ * to assume the worst case (IN_KERNEL) as we actually
+ * have no idea what we were executing when the machine
+ * check hit.
+ * If we do have a good "m->cs" (or a faked one in the
+ * case we were executing in VM86 mode) we can use it to
+ * distinguish an exception taken in user from from one
+ * taken in the kernel.
+ */
+static noinstr int error_context(struct mce *m, struct pt_regs *regs)
+{
+	int fixup_type;
+	bool copy_user;
+
+	if ((m->cs & 3) == 3)
+		return IN_USER;
+
+	if (!mc_recoverable(m->mcgstatus))
+		return IN_KERNEL;
+
+	/* Allow instrumentation around external facilities usage. */
+	instrumentation_begin();
+	fixup_type = ex_get_fixup_type(m->ip);
+	copy_user  = is_copy_from_user(regs);
+	instrumentation_end();
+
+	switch (fixup_type) {
+	case EX_TYPE_UACCESS:
+	case EX_TYPE_COPY:
+		if (!copy_user)
+			return IN_KERNEL;
+		m->kflags |= MCE_IN_KERNEL_COPYIN;
+		fallthrough;
+
+	case EX_TYPE_FAULT_MCE_SAFE:
+	case EX_TYPE_DEFAULT_MCE_SAFE:
+		m->kflags |= MCE_IN_KERNEL_RECOV;
+		return IN_KERNEL_RECOV;
+
+	default:
+		return IN_KERNEL;
+	}
+}
+
+/* See AMD PPR(s) section Machine Check Error Handling. */
+static noinstr int mce_severity_amd(struct mce *m, struct pt_regs *regs, char **msg, bool is_excp)
+{
+	char *panic_msg = NULL;
+	int ret;
+
+	/*
+	 * Default return value: Action required, the error must be handled
+	 * immediately.
+	 */
+	ret = MCE_AR_SEVERITY;
+
+	/* Processor Context Corrupt, no need to fumble too much, die! */
+	if (m->status & MCI_STATUS_PCC) {
+		panic_msg = "Processor Context Corrupt";
+		ret = MCE_PANIC_SEVERITY;
+		goto out;
+	}
+
+	if (m->status & MCI_STATUS_DEFERRED) {
+		ret = MCE_DEFERRED_SEVERITY;
+		goto out;
+	}
+
+	/*
+	 * If the UC bit is not set, the system either corrected or deferred
+	 * the error. No action will be required after logging the error.
+	 */
+	if (!(m->status & MCI_STATUS_UC)) {
+		ret = MCE_KEEP_SEVERITY;
+		goto out;
+	}
+
+	/*
+	 * On MCA overflow, without the MCA overflow recovery feature the
+	 * system will not be able to recover, panic.
+	 */
+	if ((m->status & MCI_STATUS_OVER) && !mce_flags.overflow_recov) {
+		panic_msg = "Overflowed uncorrected error without MCA Overflow Recovery";
+		ret = MCE_PANIC_SEVERITY;
+		goto out;
+	}
+
+	if (!mce_flags.succor) {
+		panic_msg = "Uncorrected error without MCA Recovery";
+		ret = MCE_PANIC_SEVERITY;
+		goto out;
+	}
+
+	if (error_context(m, regs) == IN_KERNEL) {
+		panic_msg = "Uncorrected unrecoverable error in kernel context";
+		ret = MCE_PANIC_SEVERITY;
+	}
+
+out:
+	if (msg && panic_msg)
+		*msg = panic_msg;
+
+	return ret;
+}
+
+static noinstr int mce_severity_intel(struct mce *m, struct pt_regs *regs, char **msg, bool is_excp)
+{
+	enum exception excp = (is_excp ? EXCP_CONTEXT : NO_EXCP);
+	enum context ctx = error_context(m, regs);
+	struct severity *s;
+
+	for (s = severities;; s++) {
+		if ((m->status & s->mask) != s->result)
+			continue;
+		if ((m->mcgstatus & s->mcgmask) != s->mcgres)
+			continue;
+		if (s->ser == SER_REQUIRED && !mca_cfg.ser)
+			continue;
+		if (s->ser == NO_SER && mca_cfg.ser)
+			continue;
+		if (s->context && ctx != s->context)
+			continue;
+		if (s->excp && excp != s->excp)
+			continue;
+		if (s->cpu_model && boot_cpu_data.x86_model != s->cpu_model)
+			continue;
+		if (s->cpu_minstepping && boot_cpu_data.x86_stepping < s->cpu_minstepping)
+			continue;
+		if (s->bank_lo && (m->bank < s->bank_lo || m->bank > s->bank_hi))
+			continue;
+		if (msg)
+			*msg = s->msg;
+		s->covered = 1;
+
+		return s->sev;
+	}
+}
+
+int noinstr mce_severity(struct mce *m, struct pt_regs *regs, char **msg, bool is_excp)
+{
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
+	    boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
+		return mce_severity_amd(m, regs, msg, is_excp);
+	else
+		return mce_severity_intel(m, regs, msg, is_excp);
+}
+
+#ifdef CONFIG_DEBUG_FS
+static void *s_start(struct seq_file *f, loff_t *pos)
+{
+	if (*pos >= ARRAY_SIZE(severities))
+		return NULL;
+	return &severities[*pos];
+}
+
+static void *s_next(struct seq_file *f, void *data, loff_t *pos)
+{
+	if (++(*pos) >= ARRAY_SIZE(severities))
+		return NULL;
+	return &severities[*pos];
+}
+
+static void s_stop(struct seq_file *f, void *data)
+{
+}
+
+static int s_show(struct seq_file *f, void *data)
+{
+	struct severity *ser = data;
+	seq_printf(f, "%d\t%s\n", ser->covered, ser->msg);
+	return 0;
+}
+
+static const struct seq_operations severities_seq_ops = {
+	.start	= s_start,
+	.next	= s_next,
+	.stop	= s_stop,
+	.show	= s_show,
+};
+
+static int severities_coverage_open(struct inode *inode, struct file *file)
+{
+	return seq_open(file, &severities_seq_ops);
+}
+
+static ssize_t severities_coverage_write(struct file *file,
+					 const char __user *ubuf,
+					 size_t count, loff_t *ppos)
+{
+	int i;
+	for (i = 0; i < ARRAY_SIZE(severities); i++)
+		severities[i].covered = 0;
+	return count;
+}
+
+static const struct file_operations severities_coverage_fops = {
+	.open		= severities_coverage_open,
+	.release	= seq_release,
+	.read		= seq_read,
+	.write		= severities_coverage_write,
+	.llseek		= seq_lseek,
+};
+
+static int __init severities_debugfs_init(void)
+{
+	struct dentry *dmce;
+
+	dmce = mce_get_debugfs_dir();
+
+	debugfs_create_file("severities-coverage", 0444, dmce, NULL,
+			    &severities_coverage_fops);
+	return 0;
+}
+late_initcall(severities_debugfs_init);
+#endif /* CONFIG_DEBUG_FS */
diff --git a/arch/x86/kernel/cpu/mce/threshold.c b/arch/x86/kernel/cpu/mce/threshold.c
new file mode 100644
index 0000000000..ef4e7bb5fd
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/threshold.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Common corrected MCE threshold handler code:
+ */
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+
+#include <asm/irq_vectors.h>
+#include <asm/traps.h>
+#include <asm/apic.h>
+#include <asm/mce.h>
+#include <asm/trace/irq_vectors.h>
+
+#include "internal.h"
+
+static void default_threshold_interrupt(void)
+{
+	pr_err("Unexpected threshold interrupt at vector %x\n",
+		THRESHOLD_APIC_VECTOR);
+}
+
+void (*mce_threshold_vector)(void) = default_threshold_interrupt;
+
+DEFINE_IDTENTRY_SYSVEC(sysvec_threshold)
+{
+	trace_threshold_apic_entry(THRESHOLD_APIC_VECTOR);
+	inc_irq_stat(irq_threshold_count);
+	mce_threshold_vector();
+	trace_threshold_apic_exit(THRESHOLD_APIC_VECTOR);
+	apic_eoi();
+}
diff --git a/arch/x86/kernel/cpu/mce/winchip.c b/arch/x86/kernel/cpu/mce/winchip.c
new file mode 100644
index 0000000000..6c99f29419
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/winchip.c
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * IDT Winchip specific Machine Check Exception Reporting
+ * (C) Copyright 2002 Alan Cox <alan@lxorguk.ukuu.org.uk>
+ */
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/hardirq.h>
+
+#include <asm/processor.h>
+#include <asm/traps.h>
+#include <asm/tlbflush.h>
+#include <asm/mce.h>
+#include <asm/msr.h>
+
+#include "internal.h"
+
+/* Machine check handler for WinChip C6: */
+noinstr void winchip_machine_check(struct pt_regs *regs)
+{
+	instrumentation_begin();
+	pr_emerg("CPU0: Machine Check Exception.\n");
+	add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE);
+	instrumentation_end();
+}
+
+/* Set up machine check reporting on the Winchip C6 series */
+void winchip_mcheck_init(struct cpuinfo_x86 *c)
+{
+	u32 lo, hi;
+
+	rdmsr(MSR_IDT_FCR1, lo, hi);
+	lo |= (1<<2);	/* Enable EIERRINT (int 18 MCE) */
+	lo &= ~(1<<4);	/* Enable MCE */
+	wrmsr(MSR_IDT_FCR1, lo, hi);
+
+	cr4_set_bits(X86_CR4_MCE);
+
+	pr_info("Winchip machine check reporting enabled on CPU#0.\n");
+}
diff --git a/arch/x86/kernel/cpu/microcode/Makefile b/arch/x86/kernel/cpu/microcode/Makefile
new file mode 100644
index 0000000000..193d98b33a
--- /dev/null
+++ b/arch/x86/kernel/cpu/microcode/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0-only
+microcode-y				:= core.o
+obj-$(CONFIG_MICROCODE)			+= microcode.o
+microcode-$(CONFIG_CPU_SUP_INTEL)	+= intel.o
+microcode-$(CONFIG_CPU_SUP_AMD)		+= amd.o
diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
new file mode 100644
index 0000000000..bbd1dc38ea
--- /dev/null
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -0,0 +1,966 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  AMD CPU Microcode Update Driver for Linux
+ *
+ *  This driver allows to upgrade microcode on F10h AMD
+ *  CPUs and later.
+ *
+ *  Copyright (C) 2008-2011 Advanced Micro Devices Inc.
+ *	          2013-2018 Borislav Petkov <bp@alien8.de>
+ *
+ *  Author: Peter Oruba <peter.oruba@amd.com>
+ *
+ *  Based on work by:
+ *  Tigran Aivazian <aivazian.tigran@gmail.com>
+ *
+ *  early loader:
+ *  Copyright (C) 2013 Advanced Micro Devices, Inc.
+ *
+ *  Author: Jacob Shin <jacob.shin@amd.com>
+ *  Fixes: Borislav Petkov <bp@suse.de>
+ */
+#define pr_fmt(fmt) "microcode: " fmt
+
+#include <linux/earlycpio.h>
+#include <linux/firmware.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/initrd.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+
+#include <asm/microcode.h>
+#include <asm/processor.h>
+#include <asm/setup.h>
+#include <asm/cpu.h>
+#include <asm/msr.h>
+
+#include "internal.h"
+
+#define UCODE_MAGIC			0x00414d44
+#define UCODE_EQUIV_CPU_TABLE_TYPE	0x00000000
+#define UCODE_UCODE_TYPE		0x00000001
+
+#define SECTION_HDR_SIZE		8
+#define CONTAINER_HDR_SZ		12
+
+struct equiv_cpu_entry {
+	u32	installed_cpu;
+	u32	fixed_errata_mask;
+	u32	fixed_errata_compare;
+	u16	equiv_cpu;
+	u16	res;
+} __packed;
+
+struct microcode_header_amd {
+	u32	data_code;
+	u32	patch_id;
+	u16	mc_patch_data_id;
+	u8	mc_patch_data_len;
+	u8	init_flag;
+	u32	mc_patch_data_checksum;
+	u32	nb_dev_id;
+	u32	sb_dev_id;
+	u16	processor_rev_id;
+	u8	nb_rev_id;
+	u8	sb_rev_id;
+	u8	bios_api_rev;
+	u8	reserved1[3];
+	u32	match_reg[8];
+} __packed;
+
+struct microcode_amd {
+	struct microcode_header_amd	hdr;
+	unsigned int			mpb[];
+};
+
+#define PATCH_MAX_SIZE (3 * PAGE_SIZE)
+
+static struct equiv_cpu_table {
+	unsigned int num_entries;
+	struct equiv_cpu_entry *entry;
+} equiv_table;
+
+/*
+ * This points to the current valid container of microcode patches which we will
+ * save from the initrd/builtin before jettisoning its contents. @mc is the
+ * microcode patch we found to match.
+ */
+struct cont_desc {
+	struct microcode_amd *mc;
+	u32		     cpuid_1_eax;
+	u32		     psize;
+	u8		     *data;
+	size_t		     size;
+};
+
+static u32 ucode_new_rev;
+
+/*
+ * Microcode patch container file is prepended to the initrd in cpio
+ * format. See Documentation/arch/x86/microcode.rst
+ */
+static const char
+ucode_path[] __maybe_unused = "kernel/x86/microcode/AuthenticAMD.bin";
+
+static u16 find_equiv_id(struct equiv_cpu_table *et, u32 sig)
+{
+	unsigned int i;
+
+	if (!et || !et->num_entries)
+		return 0;
+
+	for (i = 0; i < et->num_entries; i++) {
+		struct equiv_cpu_entry *e = &et->entry[i];
+
+		if (sig == e->installed_cpu)
+			return e->equiv_cpu;
+	}
+	return 0;
+}
+
+/*
+ * Check whether there is a valid microcode container file at the beginning
+ * of @buf of size @buf_size. Set @early to use this function in the early path.
+ */
+static bool verify_container(const u8 *buf, size_t buf_size, bool early)
+{
+	u32 cont_magic;
+
+	if (buf_size <= CONTAINER_HDR_SZ) {
+		if (!early)
+			pr_debug("Truncated microcode container header.\n");
+
+		return false;
+	}
+
+	cont_magic = *(const u32 *)buf;
+	if (cont_magic != UCODE_MAGIC) {
+		if (!early)
+			pr_debug("Invalid magic value (0x%08x).\n", cont_magic);
+
+		return false;
+	}
+
+	return true;
+}
+
+/*
+ * Check whether there is a valid, non-truncated CPU equivalence table at the
+ * beginning of @buf of size @buf_size. Set @early to use this function in the
+ * early path.
+ */
+static bool verify_equivalence_table(const u8 *buf, size_t buf_size, bool early)
+{
+	const u32 *hdr = (const u32 *)buf;
+	u32 cont_type, equiv_tbl_len;
+
+	if (!verify_container(buf, buf_size, early))
+		return false;
+
+	cont_type = hdr[1];
+	if (cont_type != UCODE_EQUIV_CPU_TABLE_TYPE) {
+		if (!early)
+			pr_debug("Wrong microcode container equivalence table type: %u.\n",
+			       cont_type);
+
+		return false;
+	}
+
+	buf_size -= CONTAINER_HDR_SZ;
+
+	equiv_tbl_len = hdr[2];
+	if (equiv_tbl_len < sizeof(struct equiv_cpu_entry) ||
+	    buf_size < equiv_tbl_len) {
+		if (!early)
+			pr_debug("Truncated equivalence table.\n");
+
+		return false;
+	}
+
+	return true;
+}
+
+/*
+ * Check whether there is a valid, non-truncated microcode patch section at the
+ * beginning of @buf of size @buf_size. Set @early to use this function in the
+ * early path.
+ *
+ * On success, @sh_psize returns the patch size according to the section header,
+ * to the caller.
+ */
+static bool
+__verify_patch_section(const u8 *buf, size_t buf_size, u32 *sh_psize, bool early)
+{
+	u32 p_type, p_size;
+	const u32 *hdr;
+
+	if (buf_size < SECTION_HDR_SIZE) {
+		if (!early)
+			pr_debug("Truncated patch section.\n");
+
+		return false;
+	}
+
+	hdr = (const u32 *)buf;
+	p_type = hdr[0];
+	p_size = hdr[1];
+
+	if (p_type != UCODE_UCODE_TYPE) {
+		if (!early)
+			pr_debug("Invalid type field (0x%x) in container file section header.\n",
+				p_type);
+
+		return false;
+	}
+
+	if (p_size < sizeof(struct microcode_header_amd)) {
+		if (!early)
+			pr_debug("Patch of size %u too short.\n", p_size);
+
+		return false;
+	}
+
+	*sh_psize = p_size;
+
+	return true;
+}
+
+/*
+ * Check whether the passed remaining file @buf_size is large enough to contain
+ * a patch of the indicated @sh_psize (and also whether this size does not
+ * exceed the per-family maximum). @sh_psize is the size read from the section
+ * header.
+ */
+static unsigned int __verify_patch_size(u8 family, u32 sh_psize, size_t buf_size)
+{
+	u32 max_size;
+
+	if (family >= 0x15)
+		return min_t(u32, sh_psize, buf_size);
+
+#define F1XH_MPB_MAX_SIZE 2048
+#define F14H_MPB_MAX_SIZE 1824
+
+	switch (family) {
+	case 0x10 ... 0x12:
+		max_size = F1XH_MPB_MAX_SIZE;
+		break;
+	case 0x14:
+		max_size = F14H_MPB_MAX_SIZE;
+		break;
+	default:
+		WARN(1, "%s: WTF family: 0x%x\n", __func__, family);
+		return 0;
+	}
+
+	if (sh_psize > min_t(u32, buf_size, max_size))
+		return 0;
+
+	return sh_psize;
+}
+
+/*
+ * Verify the patch in @buf.
+ *
+ * Returns:
+ * negative: on error
+ * positive: patch is not for this family, skip it
+ * 0: success
+ */
+static int
+verify_patch(u8 family, const u8 *buf, size_t buf_size, u32 *patch_size, bool early)
+{
+	struct microcode_header_amd *mc_hdr;
+	unsigned int ret;
+	u32 sh_psize;
+	u16 proc_id;
+	u8 patch_fam;
+
+	if (!__verify_patch_section(buf, buf_size, &sh_psize, early))
+		return -1;
+
+	/*
+	 * The section header length is not included in this indicated size
+	 * but is present in the leftover file length so we need to subtract
+	 * it before passing this value to the function below.
+	 */
+	buf_size -= SECTION_HDR_SIZE;
+
+	/*
+	 * Check if the remaining buffer is big enough to contain a patch of
+	 * size sh_psize, as the section claims.
+	 */
+	if (buf_size < sh_psize) {
+		if (!early)
+			pr_debug("Patch of size %u truncated.\n", sh_psize);
+
+		return -1;
+	}
+
+	ret = __verify_patch_size(family, sh_psize, buf_size);
+	if (!ret) {
+		if (!early)
+			pr_debug("Per-family patch size mismatch.\n");
+		return -1;
+	}
+
+	*patch_size = sh_psize;
+
+	mc_hdr	= (struct microcode_header_amd *)(buf + SECTION_HDR_SIZE);
+	if (mc_hdr->nb_dev_id || mc_hdr->sb_dev_id) {
+		if (!early)
+			pr_err("Patch-ID 0x%08x: chipset-specific code unsupported.\n", mc_hdr->patch_id);
+		return -1;
+	}
+
+	proc_id	= mc_hdr->processor_rev_id;
+	patch_fam = 0xf + (proc_id >> 12);
+	if (patch_fam != family)
+		return 1;
+
+	return 0;
+}
+
+/*
+ * This scans the ucode blob for the proper container as we can have multiple
+ * containers glued together. Returns the equivalence ID from the equivalence
+ * table or 0 if none found.
+ * Returns the amount of bytes consumed while scanning. @desc contains all the
+ * data we're going to use in later stages of the application.
+ */
+static size_t parse_container(u8 *ucode, size_t size, struct cont_desc *desc)
+{
+	struct equiv_cpu_table table;
+	size_t orig_size = size;
+	u32 *hdr = (u32 *)ucode;
+	u16 eq_id;
+	u8 *buf;
+
+	if (!verify_equivalence_table(ucode, size, true))
+		return 0;
+
+	buf = ucode;
+
+	table.entry = (struct equiv_cpu_entry *)(buf + CONTAINER_HDR_SZ);
+	table.num_entries = hdr[2] / sizeof(struct equiv_cpu_entry);
+
+	/*
+	 * Find the equivalence ID of our CPU in this table. Even if this table
+	 * doesn't contain a patch for the CPU, scan through the whole container
+	 * so that it can be skipped in case there are other containers appended.
+	 */
+	eq_id = find_equiv_id(&table, desc->cpuid_1_eax);
+
+	buf  += hdr[2] + CONTAINER_HDR_SZ;
+	size -= hdr[2] + CONTAINER_HDR_SZ;
+
+	/*
+	 * Scan through the rest of the container to find where it ends. We do
+	 * some basic sanity-checking too.
+	 */
+	while (size > 0) {
+		struct microcode_amd *mc;
+		u32 patch_size;
+		int ret;
+
+		ret = verify_patch(x86_family(desc->cpuid_1_eax), buf, size, &patch_size, true);
+		if (ret < 0) {
+			/*
+			 * Patch verification failed, skip to the next container, if
+			 * there is one. Before exit, check whether that container has
+			 * found a patch already. If so, use it.
+			 */
+			goto out;
+		} else if (ret > 0) {
+			goto skip;
+		}
+
+		mc = (struct microcode_amd *)(buf + SECTION_HDR_SIZE);
+		if (eq_id == mc->hdr.processor_rev_id) {
+			desc->psize = patch_size;
+			desc->mc = mc;
+		}
+
+skip:
+		/* Skip patch section header too: */
+		buf  += patch_size + SECTION_HDR_SIZE;
+		size -= patch_size + SECTION_HDR_SIZE;
+	}
+
+out:
+	/*
+	 * If we have found a patch (desc->mc), it means we're looking at the
+	 * container which has a patch for this CPU so return 0 to mean, @ucode
+	 * already points to the proper container. Otherwise, we return the size
+	 * we scanned so that we can advance to the next container in the
+	 * buffer.
+	 */
+	if (desc->mc) {
+		desc->data = ucode;
+		desc->size = orig_size - size;
+
+		return 0;
+	}
+
+	return orig_size - size;
+}
+
+/*
+ * Scan the ucode blob for the proper container as we can have multiple
+ * containers glued together.
+ */
+static void scan_containers(u8 *ucode, size_t size, struct cont_desc *desc)
+{
+	while (size) {
+		size_t s = parse_container(ucode, size, desc);
+		if (!s)
+			return;
+
+		/* catch wraparound */
+		if (size >= s) {
+			ucode += s;
+			size  -= s;
+		} else {
+			return;
+		}
+	}
+}
+
+static int __apply_microcode_amd(struct microcode_amd *mc)
+{
+	u32 rev, dummy;
+
+	native_wrmsrl(MSR_AMD64_PATCH_LOADER, (u64)(long)&mc->hdr.data_code);
+
+	/* verify patch application was successful */
+	native_rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
+	if (rev != mc->hdr.patch_id)
+		return -1;
+
+	return 0;
+}
+
+/*
+ * Early load occurs before we can vmalloc(). So we look for the microcode
+ * patch container file in initrd, traverse equivalent cpu table, look for a
+ * matching microcode patch, and update, all in initrd memory in place.
+ * When vmalloc() is available for use later -- on 64-bit during first AP load,
+ * and on 32-bit during save_microcode_in_initrd_amd() -- we can call
+ * load_microcode_amd() to save equivalent cpu table and microcode patches in
+ * kernel heap memory.
+ *
+ * Returns true if container found (sets @desc), false otherwise.
+ */
+static bool early_apply_microcode(u32 cpuid_1_eax, void *ucode, size_t size)
+{
+	struct cont_desc desc = { 0 };
+	struct microcode_amd *mc;
+	u32 rev, dummy, *new_rev;
+	bool ret = false;
+
+#ifdef CONFIG_X86_32
+	new_rev = (u32 *)__pa_nodebug(&ucode_new_rev);
+#else
+	new_rev = &ucode_new_rev;
+#endif
+
+	desc.cpuid_1_eax = cpuid_1_eax;
+
+	scan_containers(ucode, size, &desc);
+
+	mc = desc.mc;
+	if (!mc)
+		return ret;
+
+	native_rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
+
+	/*
+	 * Allow application of the same revision to pick up SMT-specific
+	 * changes even if the revision of the other SMT thread is already
+	 * up-to-date.
+	 */
+	if (rev > mc->hdr.patch_id)
+		return ret;
+
+	if (!__apply_microcode_amd(mc)) {
+		*new_rev = mc->hdr.patch_id;
+		ret      = true;
+	}
+
+	return ret;
+}
+
+static bool get_builtin_microcode(struct cpio_data *cp, unsigned int family)
+{
+	char fw_name[36] = "amd-ucode/microcode_amd.bin";
+	struct firmware fw;
+
+	if (IS_ENABLED(CONFIG_X86_32))
+		return false;
+
+	if (family >= 0x15)
+		snprintf(fw_name, sizeof(fw_name),
+			 "amd-ucode/microcode_amd_fam%.2xh.bin", family);
+
+	if (firmware_request_builtin(&fw, fw_name)) {
+		cp->size = fw.size;
+		cp->data = (void *)fw.data;
+		return true;
+	}
+
+	return false;
+}
+
+static void find_blobs_in_containers(unsigned int cpuid_1_eax, struct cpio_data *ret)
+{
+	struct ucode_cpu_info *uci;
+	struct cpio_data cp;
+	const char *path;
+	bool use_pa;
+
+	if (IS_ENABLED(CONFIG_X86_32)) {
+		uci	= (struct ucode_cpu_info *)__pa_nodebug(ucode_cpu_info);
+		path	= (const char *)__pa_nodebug(ucode_path);
+		use_pa	= true;
+	} else {
+		uci     = ucode_cpu_info;
+		path	= ucode_path;
+		use_pa	= false;
+	}
+
+	if (!get_builtin_microcode(&cp, x86_family(cpuid_1_eax)))
+		cp = find_microcode_in_initrd(path, use_pa);
+
+	/* Needed in load_microcode_amd() */
+	uci->cpu_sig.sig = cpuid_1_eax;
+
+	*ret = cp;
+}
+
+static void apply_ucode_from_containers(unsigned int cpuid_1_eax)
+{
+	struct cpio_data cp = { };
+
+	find_blobs_in_containers(cpuid_1_eax, &cp);
+	if (!(cp.data && cp.size))
+		return;
+
+	early_apply_microcode(cpuid_1_eax, cp.data, cp.size);
+}
+
+void load_ucode_amd_early(unsigned int cpuid_1_eax)
+{
+	return apply_ucode_from_containers(cpuid_1_eax);
+}
+
+static enum ucode_state load_microcode_amd(u8 family, const u8 *data, size_t size);
+
+int __init save_microcode_in_initrd_amd(unsigned int cpuid_1_eax)
+{
+	struct cont_desc desc = { 0 };
+	enum ucode_state ret;
+	struct cpio_data cp;
+
+	cp = find_microcode_in_initrd(ucode_path, false);
+	if (!(cp.data && cp.size))
+		return -EINVAL;
+
+	desc.cpuid_1_eax = cpuid_1_eax;
+
+	scan_containers(cp.data, cp.size, &desc);
+	if (!desc.mc)
+		return -EINVAL;
+
+	ret = load_microcode_amd(x86_family(cpuid_1_eax), desc.data, desc.size);
+	if (ret > UCODE_UPDATED)
+		return -EINVAL;
+
+	return 0;
+}
+
+/*
+ * a small, trivial cache of per-family ucode patches
+ */
+static struct ucode_patch *cache_find_patch(u16 equiv_cpu)
+{
+	struct ucode_patch *p;
+
+	list_for_each_entry(p, &microcode_cache, plist)
+		if (p->equiv_cpu == equiv_cpu)
+			return p;
+	return NULL;
+}
+
+static void update_cache(struct ucode_patch *new_patch)
+{
+	struct ucode_patch *p;
+
+	list_for_each_entry(p, &microcode_cache, plist) {
+		if (p->equiv_cpu == new_patch->equiv_cpu) {
+			if (p->patch_id >= new_patch->patch_id) {
+				/* we already have the latest patch */
+				kfree(new_patch->data);
+				kfree(new_patch);
+				return;
+			}
+
+			list_replace(&p->plist, &new_patch->plist);
+			kfree(p->data);
+			kfree(p);
+			return;
+		}
+	}
+	/* no patch found, add it */
+	list_add_tail(&new_patch->plist, &microcode_cache);
+}
+
+static void free_cache(void)
+{
+	struct ucode_patch *p, *tmp;
+
+	list_for_each_entry_safe(p, tmp, &microcode_cache, plist) {
+		__list_del(p->plist.prev, p->plist.next);
+		kfree(p->data);
+		kfree(p);
+	}
+}
+
+static struct ucode_patch *find_patch(unsigned int cpu)
+{
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	u16 equiv_id;
+
+
+	equiv_id = find_equiv_id(&equiv_table, uci->cpu_sig.sig);
+	if (!equiv_id)
+		return NULL;
+
+	return cache_find_patch(equiv_id);
+}
+
+void reload_ucode_amd(unsigned int cpu)
+{
+	u32 rev, dummy __always_unused;
+	struct microcode_amd *mc;
+	struct ucode_patch *p;
+
+	p = find_patch(cpu);
+	if (!p)
+		return;
+
+	mc = p->data;
+
+	rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
+
+	if (rev < mc->hdr.patch_id) {
+		if (!__apply_microcode_amd(mc)) {
+			ucode_new_rev = mc->hdr.patch_id;
+			pr_info("reload patch_level=0x%08x\n", ucode_new_rev);
+		}
+	}
+}
+
+static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
+{
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	struct ucode_patch *p;
+
+	csig->sig = cpuid_eax(0x00000001);
+	csig->rev = c->microcode;
+
+	/*
+	 * a patch could have been loaded early, set uci->mc so that
+	 * mc_bp_resume() can call apply_microcode()
+	 */
+	p = find_patch(cpu);
+	if (p && (p->patch_id == csig->rev))
+		uci->mc = p->data;
+
+	pr_info("CPU%d: patch_level=0x%08x\n", cpu, csig->rev);
+
+	return 0;
+}
+
+static enum ucode_state apply_microcode_amd(int cpu)
+{
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	struct microcode_amd *mc_amd;
+	struct ucode_cpu_info *uci;
+	struct ucode_patch *p;
+	enum ucode_state ret;
+	u32 rev, dummy __always_unused;
+
+	BUG_ON(raw_smp_processor_id() != cpu);
+
+	uci = ucode_cpu_info + cpu;
+
+	p = find_patch(cpu);
+	if (!p)
+		return UCODE_NFOUND;
+
+	mc_amd  = p->data;
+	uci->mc = p->data;
+
+	rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
+
+	/* need to apply patch? */
+	if (rev > mc_amd->hdr.patch_id) {
+		ret = UCODE_OK;
+		goto out;
+	}
+
+	if (__apply_microcode_amd(mc_amd)) {
+		pr_err("CPU%d: update failed for patch_level=0x%08x\n",
+			cpu, mc_amd->hdr.patch_id);
+		return UCODE_ERROR;
+	}
+
+	rev = mc_amd->hdr.patch_id;
+	ret = UCODE_UPDATED;
+
+	pr_info("CPU%d: new patch_level=0x%08x\n", cpu, rev);
+
+out:
+	uci->cpu_sig.rev = rev;
+	c->microcode	 = rev;
+
+	/* Update boot_cpu_data's revision too, if we're on the BSP: */
+	if (c->cpu_index == boot_cpu_data.cpu_index)
+		boot_cpu_data.microcode = rev;
+
+	return ret;
+}
+
+static size_t install_equiv_cpu_table(const u8 *buf, size_t buf_size)
+{
+	u32 equiv_tbl_len;
+	const u32 *hdr;
+
+	if (!verify_equivalence_table(buf, buf_size, false))
+		return 0;
+
+	hdr = (const u32 *)buf;
+	equiv_tbl_len = hdr[2];
+
+	equiv_table.entry = vmalloc(equiv_tbl_len);
+	if (!equiv_table.entry) {
+		pr_err("failed to allocate equivalent CPU table\n");
+		return 0;
+	}
+
+	memcpy(equiv_table.entry, buf + CONTAINER_HDR_SZ, equiv_tbl_len);
+	equiv_table.num_entries = equiv_tbl_len / sizeof(struct equiv_cpu_entry);
+
+	/* add header length */
+	return equiv_tbl_len + CONTAINER_HDR_SZ;
+}
+
+static void free_equiv_cpu_table(void)
+{
+	vfree(equiv_table.entry);
+	memset(&equiv_table, 0, sizeof(equiv_table));
+}
+
+static void cleanup(void)
+{
+	free_equiv_cpu_table();
+	free_cache();
+}
+
+/*
+ * Return a non-negative value even if some of the checks failed so that
+ * we can skip over the next patch. If we return a negative value, we
+ * signal a grave error like a memory allocation has failed and the
+ * driver cannot continue functioning normally. In such cases, we tear
+ * down everything we've used up so far and exit.
+ */
+static int verify_and_add_patch(u8 family, u8 *fw, unsigned int leftover,
+				unsigned int *patch_size)
+{
+	struct microcode_header_amd *mc_hdr;
+	struct ucode_patch *patch;
+	u16 proc_id;
+	int ret;
+
+	ret = verify_patch(family, fw, leftover, patch_size, false);
+	if (ret)
+		return ret;
+
+	patch = kzalloc(sizeof(*patch), GFP_KERNEL);
+	if (!patch) {
+		pr_err("Patch allocation failure.\n");
+		return -EINVAL;
+	}
+
+	patch->data = kmemdup(fw + SECTION_HDR_SIZE, *patch_size, GFP_KERNEL);
+	if (!patch->data) {
+		pr_err("Patch data allocation failure.\n");
+		kfree(patch);
+		return -EINVAL;
+	}
+	patch->size = *patch_size;
+
+	mc_hdr      = (struct microcode_header_amd *)(fw + SECTION_HDR_SIZE);
+	proc_id     = mc_hdr->processor_rev_id;
+
+	INIT_LIST_HEAD(&patch->plist);
+	patch->patch_id  = mc_hdr->patch_id;
+	patch->equiv_cpu = proc_id;
+
+	pr_debug("%s: Added patch_id: 0x%08x, proc_id: 0x%04x\n",
+		 __func__, patch->patch_id, proc_id);
+
+	/* ... and add to cache. */
+	update_cache(patch);
+
+	return 0;
+}
+
+/* Scan the blob in @data and add microcode patches to the cache. */
+static enum ucode_state __load_microcode_amd(u8 family, const u8 *data,
+					     size_t size)
+{
+	u8 *fw = (u8 *)data;
+	size_t offset;
+
+	offset = install_equiv_cpu_table(data, size);
+	if (!offset)
+		return UCODE_ERROR;
+
+	fw   += offset;
+	size -= offset;
+
+	if (*(u32 *)fw != UCODE_UCODE_TYPE) {
+		pr_err("invalid type field in container file section header\n");
+		free_equiv_cpu_table();
+		return UCODE_ERROR;
+	}
+
+	while (size > 0) {
+		unsigned int crnt_size = 0;
+		int ret;
+
+		ret = verify_and_add_patch(family, fw, size, &crnt_size);
+		if (ret < 0)
+			return UCODE_ERROR;
+
+		fw   +=  crnt_size + SECTION_HDR_SIZE;
+		size -= (crnt_size + SECTION_HDR_SIZE);
+	}
+
+	return UCODE_OK;
+}
+
+static enum ucode_state load_microcode_amd(u8 family, const u8 *data, size_t size)
+{
+	struct cpuinfo_x86 *c;
+	unsigned int nid, cpu;
+	struct ucode_patch *p;
+	enum ucode_state ret;
+
+	/* free old equiv table */
+	free_equiv_cpu_table();
+
+	ret = __load_microcode_amd(family, data, size);
+	if (ret != UCODE_OK) {
+		cleanup();
+		return ret;
+	}
+
+	for_each_node(nid) {
+		cpu = cpumask_first(cpumask_of_node(nid));
+		c = &cpu_data(cpu);
+
+		p = find_patch(cpu);
+		if (!p)
+			continue;
+
+		if (c->microcode >= p->patch_id)
+			continue;
+
+		ret = UCODE_NEW;
+	}
+
+	return ret;
+}
+
+/*
+ * AMD microcode firmware naming convention, up to family 15h they are in
+ * the legacy file:
+ *
+ *    amd-ucode/microcode_amd.bin
+ *
+ * This legacy file is always smaller than 2K in size.
+ *
+ * Beginning with family 15h, they are in family-specific firmware files:
+ *
+ *    amd-ucode/microcode_amd_fam15h.bin
+ *    amd-ucode/microcode_amd_fam16h.bin
+ *    ...
+ *
+ * These might be larger than 2K.
+ */
+static enum ucode_state request_microcode_amd(int cpu, struct device *device)
+{
+	char fw_name[36] = "amd-ucode/microcode_amd.bin";
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	enum ucode_state ret = UCODE_NFOUND;
+	const struct firmware *fw;
+
+	if (c->x86 >= 0x15)
+		snprintf(fw_name, sizeof(fw_name), "amd-ucode/microcode_amd_fam%.2xh.bin", c->x86);
+
+	if (request_firmware_direct(&fw, (const char *)fw_name, device)) {
+		pr_debug("failed to load file %s\n", fw_name);
+		goto out;
+	}
+
+	ret = UCODE_ERROR;
+	if (!verify_container(fw->data, fw->size, false))
+		goto fw_release;
+
+	ret = load_microcode_amd(c->x86, fw->data, fw->size);
+
+ fw_release:
+	release_firmware(fw);
+
+ out:
+	return ret;
+}
+
+static void microcode_fini_cpu_amd(int cpu)
+{
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+
+	uci->mc = NULL;
+}
+
+static struct microcode_ops microcode_amd_ops = {
+	.request_microcode_fw             = request_microcode_amd,
+	.collect_cpu_info                 = collect_cpu_info_amd,
+	.apply_microcode                  = apply_microcode_amd,
+	.microcode_fini_cpu               = microcode_fini_cpu_amd,
+};
+
+struct microcode_ops * __init init_amd_microcode(void)
+{
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+
+	if (c->x86_vendor != X86_VENDOR_AMD || c->x86 < 0x10) {
+		pr_warn("AMD CPU family 0x%x not supported\n", c->x86);
+		return NULL;
+	}
+
+	if (ucode_new_rev)
+		pr_info_once("microcode updated early to new patch_level=0x%08x\n",
+			     ucode_new_rev);
+
+	return &microcode_amd_ops;
+}
+
+void __exit exit_amd_microcode(void)
+{
+	cleanup();
+}
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
new file mode 100644
index 0000000000..a4ebd5e0ae
--- /dev/null
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -0,0 +1,684 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * CPU Microcode Update Driver for Linux
+ *
+ * Copyright (C) 2000-2006 Tigran Aivazian <aivazian.tigran@gmail.com>
+ *	      2006	Shaohua Li <shaohua.li@intel.com>
+ *	      2013-2016	Borislav Petkov <bp@alien8.de>
+ *
+ * X86 CPU microcode early update for Linux:
+ *
+ *	Copyright (C) 2012 Fenghua Yu <fenghua.yu@intel.com>
+ *			   H Peter Anvin" <hpa@zytor.com>
+ *		  (C) 2015 Borislav Petkov <bp@alien8.de>
+ *
+ * This driver allows to upgrade microcode on x86 processors.
+ */
+
+#define pr_fmt(fmt) "microcode: " fmt
+
+#include <linux/platform_device.h>
+#include <linux/stop_machine.h>
+#include <linux/syscore_ops.h>
+#include <linux/miscdevice.h>
+#include <linux/capability.h>
+#include <linux/firmware.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/cpu.h>
+#include <linux/nmi.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+
+#include <asm/cpu_device_id.h>
+#include <asm/perf_event.h>
+#include <asm/processor.h>
+#include <asm/cmdline.h>
+#include <asm/setup.h>
+
+#include "internal.h"
+
+#define DRIVER_VERSION	"2.2"
+
+static struct microcode_ops	*microcode_ops;
+static bool dis_ucode_ldr = true;
+
+bool initrd_gone;
+
+LIST_HEAD(microcode_cache);
+
+/*
+ * Synchronization.
+ *
+ * All non cpu-hotplug-callback call sites use:
+ *
+ * - cpus_read_lock/unlock() to synchronize with
+ *   the cpu-hotplug-callback call sites.
+ *
+ * We guarantee that only a single cpu is being
+ * updated at any particular moment of time.
+ */
+struct ucode_cpu_info		ucode_cpu_info[NR_CPUS];
+
+struct cpu_info_ctx {
+	struct cpu_signature	*cpu_sig;
+	int			err;
+};
+
+/*
+ * Those patch levels cannot be updated to newer ones and thus should be final.
+ */
+static u32 final_levels[] = {
+	0x01000098,
+	0x0100009f,
+	0x010000af,
+	0, /* T-101 terminator */
+};
+
+/*
+ * Check the current patch level on this CPU.
+ *
+ * Returns:
+ *  - true: if update should stop
+ *  - false: otherwise
+ */
+static bool amd_check_current_patch_level(void)
+{
+	u32 lvl, dummy, i;
+	u32 *levels;
+
+	native_rdmsr(MSR_AMD64_PATCH_LEVEL, lvl, dummy);
+
+	if (IS_ENABLED(CONFIG_X86_32))
+		levels = (u32 *)__pa_nodebug(&final_levels);
+	else
+		levels = final_levels;
+
+	for (i = 0; levels[i]; i++) {
+		if (lvl == levels[i])
+			return true;
+	}
+	return false;
+}
+
+static bool __init check_loader_disabled_bsp(void)
+{
+	static const char *__dis_opt_str = "dis_ucode_ldr";
+
+#ifdef CONFIG_X86_32
+	const char *cmdline = (const char *)__pa_nodebug(boot_command_line);
+	const char *option  = (const char *)__pa_nodebug(__dis_opt_str);
+	bool *res = (bool *)__pa_nodebug(&dis_ucode_ldr);
+
+#else /* CONFIG_X86_64 */
+	const char *cmdline = boot_command_line;
+	const char *option  = __dis_opt_str;
+	bool *res = &dis_ucode_ldr;
+#endif
+
+	/*
+	 * CPUID(1).ECX[31]: reserved for hypervisor use. This is still not
+	 * completely accurate as xen pv guests don't see that CPUID bit set but
+	 * that's good enough as they don't land on the BSP path anyway.
+	 */
+	if (native_cpuid_ecx(1) & BIT(31))
+		return *res;
+
+	if (x86_cpuid_vendor() == X86_VENDOR_AMD) {
+		if (amd_check_current_patch_level())
+			return *res;
+	}
+
+	if (cmdline_find_option_bool(cmdline, option) <= 0)
+		*res = false;
+
+	return *res;
+}
+
+void __init load_ucode_bsp(void)
+{
+	unsigned int cpuid_1_eax;
+	bool intel = true;
+
+	if (!have_cpuid_p())
+		return;
+
+	cpuid_1_eax = native_cpuid_eax(1);
+
+	switch (x86_cpuid_vendor()) {
+	case X86_VENDOR_INTEL:
+		if (x86_family(cpuid_1_eax) < 6)
+			return;
+		break;
+
+	case X86_VENDOR_AMD:
+		if (x86_family(cpuid_1_eax) < 0x10)
+			return;
+		intel = false;
+		break;
+
+	default:
+		return;
+	}
+
+	if (check_loader_disabled_bsp())
+		return;
+
+	if (intel)
+		load_ucode_intel_bsp();
+	else
+		load_ucode_amd_early(cpuid_1_eax);
+}
+
+static bool check_loader_disabled_ap(void)
+{
+#ifdef CONFIG_X86_32
+	return *((bool *)__pa_nodebug(&dis_ucode_ldr));
+#else
+	return dis_ucode_ldr;
+#endif
+}
+
+void load_ucode_ap(void)
+{
+	unsigned int cpuid_1_eax;
+
+	if (check_loader_disabled_ap())
+		return;
+
+	cpuid_1_eax = native_cpuid_eax(1);
+
+	switch (x86_cpuid_vendor()) {
+	case X86_VENDOR_INTEL:
+		if (x86_family(cpuid_1_eax) >= 6)
+			load_ucode_intel_ap();
+		break;
+	case X86_VENDOR_AMD:
+		if (x86_family(cpuid_1_eax) >= 0x10)
+			load_ucode_amd_early(cpuid_1_eax);
+		break;
+	default:
+		break;
+	}
+}
+
+static int __init save_microcode_in_initrd(void)
+{
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+	int ret = -EINVAL;
+
+	if (dis_ucode_ldr) {
+		ret = 0;
+		goto out;
+	}
+
+	switch (c->x86_vendor) {
+	case X86_VENDOR_INTEL:
+		if (c->x86 >= 6)
+			ret = save_microcode_in_initrd_intel();
+		break;
+	case X86_VENDOR_AMD:
+		if (c->x86 >= 0x10)
+			ret = save_microcode_in_initrd_amd(cpuid_eax(1));
+		break;
+	default:
+		break;
+	}
+
+out:
+	initrd_gone = true;
+
+	return ret;
+}
+
+struct cpio_data find_microcode_in_initrd(const char *path, bool use_pa)
+{
+#ifdef CONFIG_BLK_DEV_INITRD
+	unsigned long start = 0;
+	size_t size;
+
+#ifdef CONFIG_X86_32
+	struct boot_params *params;
+
+	if (use_pa)
+		params = (struct boot_params *)__pa_nodebug(&boot_params);
+	else
+		params = &boot_params;
+
+	size = params->hdr.ramdisk_size;
+
+	/*
+	 * Set start only if we have an initrd image. We cannot use initrd_start
+	 * because it is not set that early yet.
+	 */
+	if (size)
+		start = params->hdr.ramdisk_image;
+
+# else /* CONFIG_X86_64 */
+	size  = (unsigned long)boot_params.ext_ramdisk_size << 32;
+	size |= boot_params.hdr.ramdisk_size;
+
+	if (size) {
+		start  = (unsigned long)boot_params.ext_ramdisk_image << 32;
+		start |= boot_params.hdr.ramdisk_image;
+
+		start += PAGE_OFFSET;
+	}
+# endif
+
+	/*
+	 * Fixup the start address: after reserve_initrd() runs, initrd_start
+	 * has the virtual address of the beginning of the initrd. It also
+	 * possibly relocates the ramdisk. In either case, initrd_start contains
+	 * the updated address so use that instead.
+	 *
+	 * initrd_gone is for the hotplug case where we've thrown out initrd
+	 * already.
+	 */
+	if (!use_pa) {
+		if (initrd_gone)
+			return (struct cpio_data){ NULL, 0, "" };
+		if (initrd_start)
+			start = initrd_start;
+	} else {
+		/*
+		 * The picture with physical addresses is a bit different: we
+		 * need to get the *physical* address to which the ramdisk was
+		 * relocated, i.e., relocated_ramdisk (not initrd_start) and
+		 * since we're running from physical addresses, we need to access
+		 * relocated_ramdisk through its *physical* address too.
+		 */
+		u64 *rr = (u64 *)__pa_nodebug(&relocated_ramdisk);
+		if (*rr)
+			start = *rr;
+	}
+
+	return find_cpio_data(path, (void *)start, size, NULL);
+#else /* !CONFIG_BLK_DEV_INITRD */
+	return (struct cpio_data){ NULL, 0, "" };
+#endif
+}
+
+static void reload_early_microcode(unsigned int cpu)
+{
+	int vendor, family;
+
+	vendor = x86_cpuid_vendor();
+	family = x86_cpuid_family();
+
+	switch (vendor) {
+	case X86_VENDOR_INTEL:
+		if (family >= 6)
+			reload_ucode_intel();
+		break;
+	case X86_VENDOR_AMD:
+		if (family >= 0x10)
+			reload_ucode_amd(cpu);
+		break;
+	default:
+		break;
+	}
+}
+
+/* fake device for request_firmware */
+static struct platform_device	*microcode_pdev;
+
+#ifdef CONFIG_MICROCODE_LATE_LOADING
+/*
+ * Late loading dance. Why the heavy-handed stomp_machine effort?
+ *
+ * - HT siblings must be idle and not execute other code while the other sibling
+ *   is loading microcode in order to avoid any negative interactions caused by
+ *   the loading.
+ *
+ * - In addition, microcode update on the cores must be serialized until this
+ *   requirement can be relaxed in the future. Right now, this is conservative
+ *   and good.
+ */
+#define SPINUNIT 100 /* 100 nsec */
+
+static int check_online_cpus(void)
+{
+	unsigned int cpu;
+
+	/*
+	 * Make sure all CPUs are online.  It's fine for SMT to be disabled if
+	 * all the primary threads are still online.
+	 */
+	for_each_present_cpu(cpu) {
+		if (topology_is_primary_thread(cpu) && !cpu_online(cpu)) {
+			pr_err("Not all CPUs online, aborting microcode update.\n");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+static atomic_t late_cpus_in;
+static atomic_t late_cpus_out;
+
+static int __wait_for_cpus(atomic_t *t, long long timeout)
+{
+	int all_cpus = num_online_cpus();
+
+	atomic_inc(t);
+
+	while (atomic_read(t) < all_cpus) {
+		if (timeout < SPINUNIT) {
+			pr_err("Timeout while waiting for CPUs rendezvous, remaining: %d\n",
+				all_cpus - atomic_read(t));
+			return 1;
+		}
+
+		ndelay(SPINUNIT);
+		timeout -= SPINUNIT;
+
+		touch_nmi_watchdog();
+	}
+	return 0;
+}
+
+/*
+ * Returns:
+ * < 0 - on error
+ *   0 - success (no update done or microcode was updated)
+ */
+static int __reload_late(void *info)
+{
+	int cpu = smp_processor_id();
+	enum ucode_state err;
+	int ret = 0;
+
+	/*
+	 * Wait for all CPUs to arrive. A load will not be attempted unless all
+	 * CPUs show up.
+	 * */
+	if (__wait_for_cpus(&late_cpus_in, NSEC_PER_SEC))
+		return -1;
+
+	/*
+	 * On an SMT system, it suffices to load the microcode on one sibling of
+	 * the core because the microcode engine is shared between the threads.
+	 * Synchronization still needs to take place so that no concurrent
+	 * loading attempts happen on multiple threads of an SMT core. See
+	 * below.
+	 */
+	if (cpumask_first(topology_sibling_cpumask(cpu)) == cpu)
+		err = microcode_ops->apply_microcode(cpu);
+	else
+		goto wait_for_siblings;
+
+	if (err >= UCODE_NFOUND) {
+		if (err == UCODE_ERROR) {
+			pr_warn("Error reloading microcode on CPU %d\n", cpu);
+			ret = -1;
+		}
+	}
+
+wait_for_siblings:
+	if (__wait_for_cpus(&late_cpus_out, NSEC_PER_SEC))
+		panic("Timeout during microcode update!\n");
+
+	/*
+	 * At least one thread has completed update on each core.
+	 * For others, simply call the update to make sure the
+	 * per-cpu cpuinfo can be updated with right microcode
+	 * revision.
+	 */
+	if (cpumask_first(topology_sibling_cpumask(cpu)) != cpu)
+		err = microcode_ops->apply_microcode(cpu);
+
+	return ret;
+}
+
+/*
+ * Reload microcode late on all CPUs. Wait for a sec until they
+ * all gather together.
+ */
+static int microcode_reload_late(void)
+{
+	int old = boot_cpu_data.microcode, ret;
+	struct cpuinfo_x86 prev_info;
+
+	pr_err("Attempting late microcode loading - it is dangerous and taints the kernel.\n");
+	pr_err("You should switch to early loading, if possible.\n");
+
+	atomic_set(&late_cpus_in,  0);
+	atomic_set(&late_cpus_out, 0);
+
+	/*
+	 * Take a snapshot before the microcode update in order to compare and
+	 * check whether any bits changed after an update.
+	 */
+	store_cpu_caps(&prev_info);
+
+	ret = stop_machine_cpuslocked(__reload_late, NULL, cpu_online_mask);
+	if (!ret) {
+		pr_info("Reload succeeded, microcode revision: 0x%x -> 0x%x\n",
+			old, boot_cpu_data.microcode);
+		microcode_check(&prev_info);
+	} else {
+		pr_info("Reload failed, current microcode revision: 0x%x\n",
+			boot_cpu_data.microcode);
+	}
+
+	return ret;
+}
+
+static ssize_t reload_store(struct device *dev,
+			    struct device_attribute *attr,
+			    const char *buf, size_t size)
+{
+	enum ucode_state tmp_ret = UCODE_OK;
+	int bsp = boot_cpu_data.cpu_index;
+	unsigned long val;
+	ssize_t ret = 0;
+
+	ret = kstrtoul(buf, 0, &val);
+	if (ret || val != 1)
+		return -EINVAL;
+
+	cpus_read_lock();
+
+	ret = check_online_cpus();
+	if (ret)
+		goto put;
+
+	tmp_ret = microcode_ops->request_microcode_fw(bsp, &microcode_pdev->dev);
+	if (tmp_ret != UCODE_NEW)
+		goto put;
+
+	ret = microcode_reload_late();
+put:
+	cpus_read_unlock();
+
+	if (ret == 0)
+		ret = size;
+
+	add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
+
+	return ret;
+}
+
+static DEVICE_ATTR_WO(reload);
+#endif
+
+static ssize_t version_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
+
+	return sprintf(buf, "0x%x\n", uci->cpu_sig.rev);
+}
+
+static ssize_t processor_flags_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
+
+	return sprintf(buf, "0x%x\n", uci->cpu_sig.pf);
+}
+
+static DEVICE_ATTR_RO(version);
+static DEVICE_ATTR_RO(processor_flags);
+
+static struct attribute *mc_default_attrs[] = {
+	&dev_attr_version.attr,
+	&dev_attr_processor_flags.attr,
+	NULL
+};
+
+static const struct attribute_group mc_attr_group = {
+	.attrs			= mc_default_attrs,
+	.name			= "microcode",
+};
+
+static void microcode_fini_cpu(int cpu)
+{
+	if (microcode_ops->microcode_fini_cpu)
+		microcode_ops->microcode_fini_cpu(cpu);
+}
+
+static enum ucode_state microcode_init_cpu(int cpu)
+{
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+
+	memset(uci, 0, sizeof(*uci));
+
+	microcode_ops->collect_cpu_info(cpu, &uci->cpu_sig);
+
+	return microcode_ops->apply_microcode(cpu);
+}
+
+/**
+ * microcode_bsp_resume - Update boot CPU microcode during resume.
+ */
+void microcode_bsp_resume(void)
+{
+	int cpu = smp_processor_id();
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+
+	if (uci->mc)
+		microcode_ops->apply_microcode(cpu);
+	else
+		reload_early_microcode(cpu);
+}
+
+static struct syscore_ops mc_syscore_ops = {
+	.resume	= microcode_bsp_resume,
+};
+
+static int mc_cpu_starting(unsigned int cpu)
+{
+	enum ucode_state err = microcode_ops->apply_microcode(cpu);
+
+	pr_debug("%s: CPU%d, err: %d\n", __func__, cpu, err);
+
+	return err == UCODE_ERROR;
+}
+
+static int mc_cpu_online(unsigned int cpu)
+{
+	struct device *dev = get_cpu_device(cpu);
+
+	if (sysfs_create_group(&dev->kobj, &mc_attr_group))
+		pr_err("Failed to create group for CPU%d\n", cpu);
+	return 0;
+}
+
+static int mc_cpu_down_prep(unsigned int cpu)
+{
+	struct device *dev;
+
+	dev = get_cpu_device(cpu);
+
+	microcode_fini_cpu(cpu);
+
+	/* Suspend is in progress, only remove the interface */
+	sysfs_remove_group(&dev->kobj, &mc_attr_group);
+	pr_debug("%s: CPU%d\n", __func__, cpu);
+
+	return 0;
+}
+
+static void setup_online_cpu(struct work_struct *work)
+{
+	int cpu = smp_processor_id();
+	enum ucode_state err;
+
+	err = microcode_init_cpu(cpu);
+	if (err == UCODE_ERROR) {
+		pr_err("Error applying microcode on CPU%d\n", cpu);
+		return;
+	}
+
+	mc_cpu_online(cpu);
+}
+
+static struct attribute *cpu_root_microcode_attrs[] = {
+#ifdef CONFIG_MICROCODE_LATE_LOADING
+	&dev_attr_reload.attr,
+#endif
+	NULL
+};
+
+static const struct attribute_group cpu_root_microcode_group = {
+	.name  = "microcode",
+	.attrs = cpu_root_microcode_attrs,
+};
+
+static int __init microcode_init(void)
+{
+	struct device *dev_root;
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+	int error;
+
+	if (dis_ucode_ldr)
+		return -EINVAL;
+
+	if (c->x86_vendor == X86_VENDOR_INTEL)
+		microcode_ops = init_intel_microcode();
+	else if (c->x86_vendor == X86_VENDOR_AMD)
+		microcode_ops = init_amd_microcode();
+	else
+		pr_err("no support for this CPU vendor\n");
+
+	if (!microcode_ops)
+		return -ENODEV;
+
+	microcode_pdev = platform_device_register_simple("microcode", -1, NULL, 0);
+	if (IS_ERR(microcode_pdev))
+		return PTR_ERR(microcode_pdev);
+
+	dev_root = bus_get_dev_root(&cpu_subsys);
+	if (dev_root) {
+		error = sysfs_create_group(&dev_root->kobj, &cpu_root_microcode_group);
+		put_device(dev_root);
+		if (error) {
+			pr_err("Error creating microcode group!\n");
+			goto out_pdev;
+		}
+	}
+
+	/* Do per-CPU setup */
+	schedule_on_each_cpu(setup_online_cpu);
+
+	register_syscore_ops(&mc_syscore_ops);
+	cpuhp_setup_state_nocalls(CPUHP_AP_MICROCODE_LOADER, "x86/microcode:starting",
+				  mc_cpu_starting, NULL);
+	cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "x86/microcode:online",
+				  mc_cpu_online, mc_cpu_down_prep);
+
+	pr_info("Microcode Update Driver: v%s.", DRIVER_VERSION);
+
+	return 0;
+
+ out_pdev:
+	platform_device_unregister(microcode_pdev);
+	return error;
+
+}
+fs_initcall(save_microcode_in_initrd);
+late_initcall(microcode_init);
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
new file mode 100644
index 0000000000..94dd6af9c9
--- /dev/null
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -0,0 +1,906 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Intel CPU Microcode Update Driver for Linux
+ *
+ * Copyright (C) 2000-2006 Tigran Aivazian <aivazian.tigran@gmail.com>
+ *		 2006 Shaohua Li <shaohua.li@intel.com>
+ *
+ * Intel CPU microcode early update for Linux
+ *
+ * Copyright (C) 2012 Fenghua Yu <fenghua.yu@intel.com>
+ *		      H Peter Anvin" <hpa@zytor.com>
+ */
+#define pr_fmt(fmt) "microcode: " fmt
+#include <linux/earlycpio.h>
+#include <linux/firmware.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/initrd.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/cpu.h>
+#include <linux/uio.h>
+#include <linux/mm.h>
+
+#include <asm/intel-family.h>
+#include <asm/processor.h>
+#include <asm/tlbflush.h>
+#include <asm/setup.h>
+#include <asm/msr.h>
+
+#include "internal.h"
+
+static const char ucode_path[] = "kernel/x86/microcode/GenuineIntel.bin";
+
+/* Current microcode patch used in early patching on the APs. */
+static struct microcode_intel *intel_ucode_patch;
+
+/* last level cache size per core */
+static int llc_size_per_core;
+
+/* microcode format is extended from prescott processors */
+struct extended_signature {
+	unsigned int	sig;
+	unsigned int	pf;
+	unsigned int	cksum;
+};
+
+struct extended_sigtable {
+	unsigned int			count;
+	unsigned int			cksum;
+	unsigned int			reserved[3];
+	struct extended_signature	sigs[];
+};
+
+#define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE)
+#define EXT_HEADER_SIZE		(sizeof(struct extended_sigtable))
+#define EXT_SIGNATURE_SIZE	(sizeof(struct extended_signature))
+
+static inline unsigned int get_totalsize(struct microcode_header_intel *hdr)
+{
+	return hdr->datasize ? hdr->totalsize : DEFAULT_UCODE_TOTALSIZE;
+}
+
+static inline unsigned int exttable_size(struct extended_sigtable *et)
+{
+	return et->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE;
+}
+
+int intel_cpu_collect_info(struct ucode_cpu_info *uci)
+{
+	unsigned int val[2];
+	unsigned int family, model;
+	struct cpu_signature csig = { 0 };
+	unsigned int eax, ebx, ecx, edx;
+
+	memset(uci, 0, sizeof(*uci));
+
+	eax = 0x00000001;
+	ecx = 0;
+	native_cpuid(&eax, &ebx, &ecx, &edx);
+	csig.sig = eax;
+
+	family = x86_family(eax);
+	model  = x86_model(eax);
+
+	if (model >= 5 || family > 6) {
+		/* get processor flags from MSR 0x17 */
+		native_rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
+		csig.pf = 1 << ((val[1] >> 18) & 7);
+	}
+
+	csig.rev = intel_get_microcode_revision();
+
+	uci->cpu_sig = csig;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(intel_cpu_collect_info);
+
+/*
+ * Returns 1 if update has been found, 0 otherwise.
+ */
+int intel_find_matching_signature(void *mc, unsigned int csig, int cpf)
+{
+	struct microcode_header_intel *mc_hdr = mc;
+	struct extended_sigtable *ext_hdr;
+	struct extended_signature *ext_sig;
+	int i;
+
+	if (intel_cpu_signatures_match(csig, cpf, mc_hdr->sig, mc_hdr->pf))
+		return 1;
+
+	/* Look for ext. headers: */
+	if (get_totalsize(mc_hdr) <= intel_microcode_get_datasize(mc_hdr) + MC_HEADER_SIZE)
+		return 0;
+
+	ext_hdr = mc + intel_microcode_get_datasize(mc_hdr) + MC_HEADER_SIZE;
+	ext_sig = (void *)ext_hdr + EXT_HEADER_SIZE;
+
+	for (i = 0; i < ext_hdr->count; i++) {
+		if (intel_cpu_signatures_match(csig, cpf, ext_sig->sig, ext_sig->pf))
+			return 1;
+		ext_sig++;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(intel_find_matching_signature);
+
+/**
+ * intel_microcode_sanity_check() - Sanity check microcode file.
+ * @mc: Pointer to the microcode file contents.
+ * @print_err: Display failure reason if true, silent if false.
+ * @hdr_type: Type of file, i.e. normal microcode file or In Field Scan file.
+ *            Validate if the microcode header type matches with the type
+ *            specified here.
+ *
+ * Validate certain header fields and verify if computed checksum matches
+ * with the one specified in the header.
+ *
+ * Return: 0 if the file passes all the checks, -EINVAL if any of the checks
+ * fail.
+ */
+int intel_microcode_sanity_check(void *mc, bool print_err, int hdr_type)
+{
+	unsigned long total_size, data_size, ext_table_size;
+	struct microcode_header_intel *mc_header = mc;
+	struct extended_sigtable *ext_header = NULL;
+	u32 sum, orig_sum, ext_sigcount = 0, i;
+	struct extended_signature *ext_sig;
+
+	total_size = get_totalsize(mc_header);
+	data_size = intel_microcode_get_datasize(mc_header);
+
+	if (data_size + MC_HEADER_SIZE > total_size) {
+		if (print_err)
+			pr_err("Error: bad microcode data file size.\n");
+		return -EINVAL;
+	}
+
+	if (mc_header->ldrver != 1 || mc_header->hdrver != hdr_type) {
+		if (print_err)
+			pr_err("Error: invalid/unknown microcode update format. Header type %d\n",
+			       mc_header->hdrver);
+		return -EINVAL;
+	}
+
+	ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
+	if (ext_table_size) {
+		u32 ext_table_sum = 0;
+		u32 *ext_tablep;
+
+		if (ext_table_size < EXT_HEADER_SIZE ||
+		    ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
+			if (print_err)
+				pr_err("Error: truncated extended signature table.\n");
+			return -EINVAL;
+		}
+
+		ext_header = mc + MC_HEADER_SIZE + data_size;
+		if (ext_table_size != exttable_size(ext_header)) {
+			if (print_err)
+				pr_err("Error: extended signature table size mismatch.\n");
+			return -EFAULT;
+		}
+
+		ext_sigcount = ext_header->count;
+
+		/*
+		 * Check extended table checksum: the sum of all dwords that
+		 * comprise a valid table must be 0.
+		 */
+		ext_tablep = (u32 *)ext_header;
+
+		i = ext_table_size / sizeof(u32);
+		while (i--)
+			ext_table_sum += ext_tablep[i];
+
+		if (ext_table_sum) {
+			if (print_err)
+				pr_warn("Bad extended signature table checksum, aborting.\n");
+			return -EINVAL;
+		}
+	}
+
+	/*
+	 * Calculate the checksum of update data and header. The checksum of
+	 * valid update data and header including the extended signature table
+	 * must be 0.
+	 */
+	orig_sum = 0;
+	i = (MC_HEADER_SIZE + data_size) / sizeof(u32);
+	while (i--)
+		orig_sum += ((u32 *)mc)[i];
+
+	if (orig_sum) {
+		if (print_err)
+			pr_err("Bad microcode data checksum, aborting.\n");
+		return -EINVAL;
+	}
+
+	if (!ext_table_size)
+		return 0;
+
+	/*
+	 * Check extended signature checksum: 0 => valid.
+	 */
+	for (i = 0; i < ext_sigcount; i++) {
+		ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
+			  EXT_SIGNATURE_SIZE * i;
+
+		sum = (mc_header->sig + mc_header->pf + mc_header->cksum) -
+		      (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
+		if (sum) {
+			if (print_err)
+				pr_err("Bad extended signature checksum, aborting.\n");
+			return -EINVAL;
+		}
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(intel_microcode_sanity_check);
+
+/*
+ * Returns 1 if update has been found, 0 otherwise.
+ */
+static int has_newer_microcode(void *mc, unsigned int csig, int cpf, int new_rev)
+{
+	struct microcode_header_intel *mc_hdr = mc;
+
+	if (mc_hdr->rev <= new_rev)
+		return 0;
+
+	return intel_find_matching_signature(mc, csig, cpf);
+}
+
+static struct ucode_patch *memdup_patch(void *data, unsigned int size)
+{
+	struct ucode_patch *p;
+
+	p = kzalloc(sizeof(struct ucode_patch), GFP_KERNEL);
+	if (!p)
+		return NULL;
+
+	p->data = kmemdup(data, size, GFP_KERNEL);
+	if (!p->data) {
+		kfree(p);
+		return NULL;
+	}
+
+	return p;
+}
+
+static void save_microcode_patch(struct ucode_cpu_info *uci, void *data, unsigned int size)
+{
+	struct microcode_header_intel *mc_hdr, *mc_saved_hdr;
+	struct ucode_patch *iter, *tmp, *p = NULL;
+	bool prev_found = false;
+	unsigned int sig, pf;
+
+	mc_hdr = (struct microcode_header_intel *)data;
+
+	list_for_each_entry_safe(iter, tmp, &microcode_cache, plist) {
+		mc_saved_hdr = (struct microcode_header_intel *)iter->data;
+		sig	     = mc_saved_hdr->sig;
+		pf	     = mc_saved_hdr->pf;
+
+		if (intel_find_matching_signature(data, sig, pf)) {
+			prev_found = true;
+
+			if (mc_hdr->rev <= mc_saved_hdr->rev)
+				continue;
+
+			p = memdup_patch(data, size);
+			if (!p)
+				pr_err("Error allocating buffer %p\n", data);
+			else {
+				list_replace(&iter->plist, &p->plist);
+				kfree(iter->data);
+				kfree(iter);
+			}
+		}
+	}
+
+	/*
+	 * There weren't any previous patches found in the list cache; save the
+	 * newly found.
+	 */
+	if (!prev_found) {
+		p = memdup_patch(data, size);
+		if (!p)
+			pr_err("Error allocating buffer for %p\n", data);
+		else
+			list_add_tail(&p->plist, &microcode_cache);
+	}
+
+	if (!p)
+		return;
+
+	if (!intel_find_matching_signature(p->data, uci->cpu_sig.sig, uci->cpu_sig.pf))
+		return;
+
+	/*
+	 * Save for early loading. On 32-bit, that needs to be a physical
+	 * address as the APs are running from physical addresses, before
+	 * paging has been enabled.
+	 */
+	if (IS_ENABLED(CONFIG_X86_32))
+		intel_ucode_patch = (struct microcode_intel *)__pa_nodebug(p->data);
+	else
+		intel_ucode_patch = p->data;
+}
+
+/*
+ * Get microcode matching with BSP's model. Only CPUs with the same model as
+ * BSP can stay in the platform.
+ */
+static struct microcode_intel *
+scan_microcode(void *data, size_t size, struct ucode_cpu_info *uci, bool save)
+{
+	struct microcode_header_intel *mc_header;
+	struct microcode_intel *patch = NULL;
+	unsigned int mc_size;
+
+	while (size) {
+		if (size < sizeof(struct microcode_header_intel))
+			break;
+
+		mc_header = (struct microcode_header_intel *)data;
+
+		mc_size = get_totalsize(mc_header);
+		if (!mc_size ||
+		    mc_size > size ||
+		    intel_microcode_sanity_check(data, false, MC_HEADER_TYPE_MICROCODE) < 0)
+			break;
+
+		size -= mc_size;
+
+		if (!intel_find_matching_signature(data, uci->cpu_sig.sig,
+						   uci->cpu_sig.pf)) {
+			data += mc_size;
+			continue;
+		}
+
+		if (save) {
+			save_microcode_patch(uci, data, mc_size);
+			goto next;
+		}
+
+
+		if (!patch) {
+			if (!has_newer_microcode(data,
+						 uci->cpu_sig.sig,
+						 uci->cpu_sig.pf,
+						 uci->cpu_sig.rev))
+				goto next;
+
+		} else {
+			struct microcode_header_intel *phdr = &patch->hdr;
+
+			if (!has_newer_microcode(data,
+						 phdr->sig,
+						 phdr->pf,
+						 phdr->rev))
+				goto next;
+		}
+
+		/* We have a newer patch, save it. */
+		patch = data;
+
+next:
+		data += mc_size;
+	}
+
+	if (size)
+		return NULL;
+
+	return patch;
+}
+
+static bool load_builtin_intel_microcode(struct cpio_data *cp)
+{
+	unsigned int eax = 1, ebx, ecx = 0, edx;
+	struct firmware fw;
+	char name[30];
+
+	if (IS_ENABLED(CONFIG_X86_32))
+		return false;
+
+	native_cpuid(&eax, &ebx, &ecx, &edx);
+
+	sprintf(name, "intel-ucode/%02x-%02x-%02x",
+		      x86_family(eax), x86_model(eax), x86_stepping(eax));
+
+	if (firmware_request_builtin(&fw, name)) {
+		cp->size = fw.size;
+		cp->data = (void *)fw.data;
+		return true;
+	}
+
+	return false;
+}
+
+static void print_ucode_info(int old_rev, int new_rev, unsigned int date)
+{
+	pr_info_once("updated early: 0x%x -> 0x%x, date = %04x-%02x-%02x\n",
+		     old_rev,
+		     new_rev,
+		     date & 0xffff,
+		     date >> 24,
+		     (date >> 16) & 0xff);
+}
+
+#ifdef CONFIG_X86_32
+
+static int delay_ucode_info;
+static int current_mc_date;
+static int early_old_rev;
+
+/*
+ * Print early updated ucode info after printk works. This is delayed info dump.
+ */
+void show_ucode_info_early(void)
+{
+	struct ucode_cpu_info uci;
+
+	if (delay_ucode_info) {
+		intel_cpu_collect_info(&uci);
+		print_ucode_info(early_old_rev, uci.cpu_sig.rev, current_mc_date);
+		delay_ucode_info = 0;
+	}
+}
+
+/*
+ * At this point, we can not call printk() yet. Delay printing microcode info in
+ * show_ucode_info_early() until printk() works.
+ */
+static void print_ucode(int old_rev, int new_rev, int date)
+{
+	int *delay_ucode_info_p;
+	int *current_mc_date_p;
+	int *early_old_rev_p;
+
+	delay_ucode_info_p = (int *)__pa_nodebug(&delay_ucode_info);
+	current_mc_date_p = (int *)__pa_nodebug(&current_mc_date);
+	early_old_rev_p = (int *)__pa_nodebug(&early_old_rev);
+
+	*delay_ucode_info_p = 1;
+	*current_mc_date_p = date;
+	*early_old_rev_p = old_rev;
+}
+#else
+
+static inline void print_ucode(int old_rev, int new_rev, int date)
+{
+	print_ucode_info(old_rev, new_rev, date);
+}
+#endif
+
+static int apply_microcode_early(struct ucode_cpu_info *uci, bool early)
+{
+	struct microcode_intel *mc;
+	u32 rev, old_rev;
+
+	mc = uci->mc;
+	if (!mc)
+		return 0;
+
+	/*
+	 * Save us the MSR write below - which is a particular expensive
+	 * operation - when the other hyperthread has updated the microcode
+	 * already.
+	 */
+	rev = intel_get_microcode_revision();
+	if (rev >= mc->hdr.rev) {
+		uci->cpu_sig.rev = rev;
+		return UCODE_OK;
+	}
+
+	old_rev = rev;
+
+	/*
+	 * Writeback and invalidate caches before updating microcode to avoid
+	 * internal issues depending on what the microcode is updating.
+	 */
+	native_wbinvd();
+
+	/* write microcode via MSR 0x79 */
+	native_wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
+
+	rev = intel_get_microcode_revision();
+	if (rev != mc->hdr.rev)
+		return -1;
+
+	uci->cpu_sig.rev = rev;
+
+	if (early)
+		print_ucode(old_rev, uci->cpu_sig.rev, mc->hdr.date);
+	else
+		print_ucode_info(old_rev, uci->cpu_sig.rev, mc->hdr.date);
+
+	return 0;
+}
+
+int __init save_microcode_in_initrd_intel(void)
+{
+	struct ucode_cpu_info uci;
+	struct cpio_data cp;
+
+	/*
+	 * initrd is going away, clear patch ptr. We will scan the microcode one
+	 * last time before jettisoning and save a patch, if found. Then we will
+	 * update that pointer too, with a stable patch address to use when
+	 * resuming the cores.
+	 */
+	intel_ucode_patch = NULL;
+
+	if (!load_builtin_intel_microcode(&cp))
+		cp = find_microcode_in_initrd(ucode_path, false);
+
+	if (!(cp.data && cp.size))
+		return 0;
+
+	intel_cpu_collect_info(&uci);
+
+	scan_microcode(cp.data, cp.size, &uci, true);
+	return 0;
+}
+
+/*
+ * @res_patch, output: a pointer to the patch we found.
+ */
+static struct microcode_intel *__load_ucode_intel(struct ucode_cpu_info *uci)
+{
+	static const char *path;
+	struct cpio_data cp;
+	bool use_pa;
+
+	if (IS_ENABLED(CONFIG_X86_32)) {
+		path	  = (const char *)__pa_nodebug(ucode_path);
+		use_pa	  = true;
+	} else {
+		path	  = ucode_path;
+		use_pa	  = false;
+	}
+
+	/* try built-in microcode first */
+	if (!load_builtin_intel_microcode(&cp))
+		cp = find_microcode_in_initrd(path, use_pa);
+
+	if (!(cp.data && cp.size))
+		return NULL;
+
+	intel_cpu_collect_info(uci);
+
+	return scan_microcode(cp.data, cp.size, uci, false);
+}
+
+void __init load_ucode_intel_bsp(void)
+{
+	struct microcode_intel *patch;
+	struct ucode_cpu_info uci;
+
+	patch = __load_ucode_intel(&uci);
+	if (!patch)
+		return;
+
+	uci.mc = patch;
+
+	apply_microcode_early(&uci, true);
+}
+
+void load_ucode_intel_ap(void)
+{
+	struct microcode_intel *patch, **iup;
+	struct ucode_cpu_info uci;
+
+	if (IS_ENABLED(CONFIG_X86_32))
+		iup = (struct microcode_intel **) __pa_nodebug(&intel_ucode_patch);
+	else
+		iup = &intel_ucode_patch;
+
+	if (!*iup) {
+		patch = __load_ucode_intel(&uci);
+		if (!patch)
+			return;
+
+		*iup = patch;
+	}
+
+	uci.mc = *iup;
+
+	apply_microcode_early(&uci, true);
+}
+
+static struct microcode_intel *find_patch(struct ucode_cpu_info *uci)
+{
+	struct microcode_header_intel *phdr;
+	struct ucode_patch *iter, *tmp;
+
+	list_for_each_entry_safe(iter, tmp, &microcode_cache, plist) {
+
+		phdr = (struct microcode_header_intel *)iter->data;
+
+		if (phdr->rev <= uci->cpu_sig.rev)
+			continue;
+
+		if (!intel_find_matching_signature(phdr,
+						   uci->cpu_sig.sig,
+						   uci->cpu_sig.pf))
+			continue;
+
+		return iter->data;
+	}
+	return NULL;
+}
+
+void reload_ucode_intel(void)
+{
+	struct microcode_intel *p;
+	struct ucode_cpu_info uci;
+
+	intel_cpu_collect_info(&uci);
+
+	p = find_patch(&uci);
+	if (!p)
+		return;
+
+	uci.mc = p;
+
+	apply_microcode_early(&uci, false);
+}
+
+static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
+{
+	struct cpuinfo_x86 *c = &cpu_data(cpu_num);
+	unsigned int val[2];
+
+	memset(csig, 0, sizeof(*csig));
+
+	csig->sig = cpuid_eax(0x00000001);
+
+	if ((c->x86_model >= 5) || (c->x86 > 6)) {
+		/* get processor flags from MSR 0x17 */
+		rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
+		csig->pf = 1 << ((val[1] >> 18) & 7);
+	}
+
+	csig->rev = c->microcode;
+
+	return 0;
+}
+
+static enum ucode_state apply_microcode_intel(int cpu)
+{
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	bool bsp = c->cpu_index == boot_cpu_data.cpu_index;
+	struct microcode_intel *mc;
+	enum ucode_state ret;
+	static int prev_rev;
+	u32 rev;
+
+	/* We should bind the task to the CPU */
+	if (WARN_ON(raw_smp_processor_id() != cpu))
+		return UCODE_ERROR;
+
+	/* Look for a newer patch in our cache: */
+	mc = find_patch(uci);
+	if (!mc) {
+		mc = uci->mc;
+		if (!mc)
+			return UCODE_NFOUND;
+	}
+
+	/*
+	 * Save us the MSR write below - which is a particular expensive
+	 * operation - when the other hyperthread has updated the microcode
+	 * already.
+	 */
+	rev = intel_get_microcode_revision();
+	if (rev >= mc->hdr.rev) {
+		ret = UCODE_OK;
+		goto out;
+	}
+
+	/*
+	 * Writeback and invalidate caches before updating microcode to avoid
+	 * internal issues depending on what the microcode is updating.
+	 */
+	native_wbinvd();
+
+	/* write microcode via MSR 0x79 */
+	wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
+
+	rev = intel_get_microcode_revision();
+
+	if (rev != mc->hdr.rev) {
+		pr_err("CPU%d update to revision 0x%x failed\n",
+		       cpu, mc->hdr.rev);
+		return UCODE_ERROR;
+	}
+
+	if (bsp && rev != prev_rev) {
+		pr_info("updated to revision 0x%x, date = %04x-%02x-%02x\n",
+			rev,
+			mc->hdr.date & 0xffff,
+			mc->hdr.date >> 24,
+			(mc->hdr.date >> 16) & 0xff);
+		prev_rev = rev;
+	}
+
+	ret = UCODE_UPDATED;
+
+out:
+	uci->cpu_sig.rev = rev;
+	c->microcode	 = rev;
+
+	/* Update boot_cpu_data's revision too, if we're on the BSP: */
+	if (bsp)
+		boot_cpu_data.microcode = rev;
+
+	return ret;
+}
+
+static enum ucode_state generic_load_microcode(int cpu, struct iov_iter *iter)
+{
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	unsigned int curr_mc_size = 0, new_mc_size = 0;
+	enum ucode_state ret = UCODE_OK;
+	int new_rev = uci->cpu_sig.rev;
+	u8 *new_mc = NULL, *mc = NULL;
+	unsigned int csig, cpf;
+
+	while (iov_iter_count(iter)) {
+		struct microcode_header_intel mc_header;
+		unsigned int mc_size, data_size;
+		u8 *data;
+
+		if (!copy_from_iter_full(&mc_header, sizeof(mc_header), iter)) {
+			pr_err("error! Truncated or inaccessible header in microcode data file\n");
+			break;
+		}
+
+		mc_size = get_totalsize(&mc_header);
+		if (mc_size < sizeof(mc_header)) {
+			pr_err("error! Bad data in microcode data file (totalsize too small)\n");
+			break;
+		}
+		data_size = mc_size - sizeof(mc_header);
+		if (data_size > iov_iter_count(iter)) {
+			pr_err("error! Bad data in microcode data file (truncated file?)\n");
+			break;
+		}
+
+		/* For performance reasons, reuse mc area when possible */
+		if (!mc || mc_size > curr_mc_size) {
+			vfree(mc);
+			mc = vmalloc(mc_size);
+			if (!mc)
+				break;
+			curr_mc_size = mc_size;
+		}
+
+		memcpy(mc, &mc_header, sizeof(mc_header));
+		data = mc + sizeof(mc_header);
+		if (!copy_from_iter_full(data, data_size, iter) ||
+		    intel_microcode_sanity_check(mc, true, MC_HEADER_TYPE_MICROCODE) < 0) {
+			break;
+		}
+
+		csig = uci->cpu_sig.sig;
+		cpf = uci->cpu_sig.pf;
+		if (has_newer_microcode(mc, csig, cpf, new_rev)) {
+			vfree(new_mc);
+			new_rev = mc_header.rev;
+			new_mc  = mc;
+			new_mc_size = mc_size;
+			mc = NULL;	/* trigger new vmalloc */
+			ret = UCODE_NEW;
+		}
+	}
+
+	vfree(mc);
+
+	if (iov_iter_count(iter)) {
+		vfree(new_mc);
+		return UCODE_ERROR;
+	}
+
+	if (!new_mc)
+		return UCODE_NFOUND;
+
+	vfree(uci->mc);
+	uci->mc = (struct microcode_intel *)new_mc;
+
+	/* Save for CPU hotplug */
+	save_microcode_patch(uci, new_mc, new_mc_size);
+
+	pr_debug("CPU%d found a matching microcode update with version 0x%x (current=0x%x)\n",
+		 cpu, new_rev, uci->cpu_sig.rev);
+
+	return ret;
+}
+
+static bool is_blacklisted(unsigned int cpu)
+{
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+
+	/*
+	 * Late loading on model 79 with microcode revision less than 0x0b000021
+	 * and LLC size per core bigger than 2.5MB may result in a system hang.
+	 * This behavior is documented in item BDF90, #334165 (Intel Xeon
+	 * Processor E7-8800/4800 v4 Product Family).
+	 */
+	if (c->x86 == 6 &&
+	    c->x86_model == INTEL_FAM6_BROADWELL_X &&
+	    c->x86_stepping == 0x01 &&
+	    llc_size_per_core > 2621440 &&
+	    c->microcode < 0x0b000021) {
+		pr_err_once("Erratum BDF90: late loading with revision < 0x0b000021 (0x%x) disabled.\n", c->microcode);
+		pr_err_once("Please consider either early loading through initrd/built-in or a potential BIOS update.\n");
+		return true;
+	}
+
+	return false;
+}
+
+static enum ucode_state request_microcode_fw(int cpu, struct device *device)
+{
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	const struct firmware *firmware;
+	struct iov_iter iter;
+	enum ucode_state ret;
+	struct kvec kvec;
+	char name[30];
+
+	if (is_blacklisted(cpu))
+		return UCODE_NFOUND;
+
+	sprintf(name, "intel-ucode/%02x-%02x-%02x",
+		c->x86, c->x86_model, c->x86_stepping);
+
+	if (request_firmware_direct(&firmware, name, device)) {
+		pr_debug("data file %s load failed\n", name);
+		return UCODE_NFOUND;
+	}
+
+	kvec.iov_base = (void *)firmware->data;
+	kvec.iov_len = firmware->size;
+	iov_iter_kvec(&iter, ITER_SOURCE, &kvec, 1, firmware->size);
+	ret = generic_load_microcode(cpu, &iter);
+
+	release_firmware(firmware);
+
+	return ret;
+}
+
+static struct microcode_ops microcode_intel_ops = {
+	.request_microcode_fw             = request_microcode_fw,
+	.collect_cpu_info                 = collect_cpu_info,
+	.apply_microcode                  = apply_microcode_intel,
+};
+
+static int __init calc_llc_size_per_core(struct cpuinfo_x86 *c)
+{
+	u64 llc_size = c->x86_cache_size * 1024ULL;
+
+	do_div(llc_size, c->x86_max_cores);
+
+	return (int)llc_size;
+}
+
+struct microcode_ops * __init init_intel_microcode(void)
+{
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+
+	if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
+	    cpu_has(c, X86_FEATURE_IA64)) {
+		pr_err("Intel CPU family 0x%x not supported\n", c->x86);
+		return NULL;
+	}
+
+	llc_size_per_core = calc_llc_size_per_core(c);
+
+	return &microcode_intel_ops;
+}
diff --git a/arch/x86/kernel/cpu/microcode/internal.h b/arch/x86/kernel/cpu/microcode/internal.h
new file mode 100644
index 0000000000..bf883aa712
--- /dev/null
+++ b/arch/x86/kernel/cpu/microcode/internal.h
@@ -0,0 +1,131 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _X86_MICROCODE_INTERNAL_H
+#define _X86_MICROCODE_INTERNAL_H
+
+#include <linux/earlycpio.h>
+#include <linux/initrd.h>
+
+#include <asm/cpu.h>
+#include <asm/microcode.h>
+
+struct ucode_patch {
+	struct list_head plist;
+	void *data;		/* Intel uses only this one */
+	unsigned int size;
+	u32 patch_id;
+	u16 equiv_cpu;
+};
+
+extern struct list_head microcode_cache;
+
+struct device;
+
+enum ucode_state {
+	UCODE_OK	= 0,
+	UCODE_NEW,
+	UCODE_UPDATED,
+	UCODE_NFOUND,
+	UCODE_ERROR,
+};
+
+struct microcode_ops {
+	enum ucode_state (*request_microcode_fw)(int cpu, struct device *dev);
+
+	void (*microcode_fini_cpu)(int cpu);
+
+	/*
+	 * The generic 'microcode_core' part guarantees that
+	 * the callbacks below run on a target cpu when they
+	 * are being called.
+	 * See also the "Synchronization" section in microcode_core.c.
+	 */
+	enum ucode_state (*apply_microcode)(int cpu);
+	int (*collect_cpu_info)(int cpu, struct cpu_signature *csig);
+};
+
+extern struct ucode_cpu_info ucode_cpu_info[];
+struct cpio_data find_microcode_in_initrd(const char *path, bool use_pa);
+
+#define MAX_UCODE_COUNT 128
+
+#define QCHAR(a, b, c, d) ((a) + ((b) << 8) + ((c) << 16) + ((d) << 24))
+#define CPUID_INTEL1 QCHAR('G', 'e', 'n', 'u')
+#define CPUID_INTEL2 QCHAR('i', 'n', 'e', 'I')
+#define CPUID_INTEL3 QCHAR('n', 't', 'e', 'l')
+#define CPUID_AMD1 QCHAR('A', 'u', 't', 'h')
+#define CPUID_AMD2 QCHAR('e', 'n', 't', 'i')
+#define CPUID_AMD3 QCHAR('c', 'A', 'M', 'D')
+
+#define CPUID_IS(a, b, c, ebx, ecx, edx)	\
+		(!(((ebx) ^ (a)) | ((edx) ^ (b)) | ((ecx) ^ (c))))
+
+/*
+ * In early loading microcode phase on BSP, boot_cpu_data is not set up yet.
+ * x86_cpuid_vendor() gets vendor id for BSP.
+ *
+ * In 32 bit AP case, accessing boot_cpu_data needs linear address. To simplify
+ * coding, we still use x86_cpuid_vendor() to get vendor id for AP.
+ *
+ * x86_cpuid_vendor() gets vendor information directly from CPUID.
+ */
+static inline int x86_cpuid_vendor(void)
+{
+	u32 eax = 0x00000000;
+	u32 ebx, ecx = 0, edx;
+
+	native_cpuid(&eax, &ebx, &ecx, &edx);
+
+	if (CPUID_IS(CPUID_INTEL1, CPUID_INTEL2, CPUID_INTEL3, ebx, ecx, edx))
+		return X86_VENDOR_INTEL;
+
+	if (CPUID_IS(CPUID_AMD1, CPUID_AMD2, CPUID_AMD3, ebx, ecx, edx))
+		return X86_VENDOR_AMD;
+
+	return X86_VENDOR_UNKNOWN;
+}
+
+static inline unsigned int x86_cpuid_family(void)
+{
+	u32 eax = 0x00000001;
+	u32 ebx, ecx = 0, edx;
+
+	native_cpuid(&eax, &ebx, &ecx, &edx);
+
+	return x86_family(eax);
+}
+
+extern bool initrd_gone;
+
+#ifdef CONFIG_CPU_SUP_AMD
+void load_ucode_amd_bsp(unsigned int family);
+void load_ucode_amd_ap(unsigned int family);
+void load_ucode_amd_early(unsigned int cpuid_1_eax);
+int save_microcode_in_initrd_amd(unsigned int family);
+void reload_ucode_amd(unsigned int cpu);
+struct microcode_ops *init_amd_microcode(void);
+void exit_amd_microcode(void);
+#else /* CONFIG_CPU_SUP_AMD */
+static inline void load_ucode_amd_bsp(unsigned int family) { }
+static inline void load_ucode_amd_ap(unsigned int family) { }
+static inline void load_ucode_amd_early(unsigned int family) { }
+static inline int save_microcode_in_initrd_amd(unsigned int family) { return -EINVAL; }
+static inline void reload_ucode_amd(unsigned int cpu) { }
+static inline struct microcode_ops *init_amd_microcode(void) { return NULL; }
+static inline void exit_amd_microcode(void) { }
+#endif /* !CONFIG_CPU_SUP_AMD */
+
+#ifdef CONFIG_CPU_SUP_INTEL
+void load_ucode_intel_bsp(void);
+void load_ucode_intel_ap(void);
+int save_microcode_in_initrd_intel(void);
+void reload_ucode_intel(void);
+struct microcode_ops *init_intel_microcode(void);
+#else /* CONFIG_CPU_SUP_INTEL */
+static inline void load_ucode_intel_bsp(void) { }
+static inline void load_ucode_intel_ap(void) { }
+static inline int save_microcode_in_initrd_intel(void) { return -EINVAL; }
+static inline void reload_ucode_intel(void) { }
+static inline struct microcode_ops *init_intel_microcode(void) { return NULL; }
+#endif  /* !CONFIG_CPU_SUP_INTEL */
+
+#endif /* _X86_MICROCODE_INTERNAL_H */
diff --git a/arch/x86/kernel/cpu/mkcapflags.sh b/arch/x86/kernel/cpu/mkcapflags.sh
new file mode 100644
index 0000000000..1db560ed2c
--- /dev/null
+++ b/arch/x86/kernel/cpu/mkcapflags.sh
@@ -0,0 +1,74 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Generate the x86_cap/bug_flags[] arrays from include/asm/cpufeatures.h
+#
+
+set -e
+
+OUT=$1
+
+dump_array()
+{
+	ARRAY=$1
+	SIZE=$2
+	PFX=$3
+	POSTFIX=$4
+	IN=$5
+
+	PFX_SZ=$(echo $PFX | wc -c)
+	TABS="$(printf '\t\t\t\t\t')"
+
+	echo "const char * const $ARRAY[$SIZE] = {"
+
+	# Iterate through any input lines starting with #define $PFX
+	sed -n -e 's/\t/ /g' -e "s/^ *# *define *$PFX//p" $IN |
+	while read i
+	do
+		# Name is everything up to the first whitespace
+		NAME="$(echo "$i" | sed 's/ .*//')"
+
+		# If the /* comment */ starts with a quote string, grab that.
+		VALUE="$(echo "$i" | sed -n 's@.*/\* *\("[^"]*"\).*\*/@\1@p')"
+		[ -z "$VALUE" ] && VALUE="\"$NAME\""
+		[ "$VALUE" = '""' ] && continue
+
+		# Name is uppercase, VALUE is all lowercase
+		VALUE="$(echo "$VALUE" | tr A-Z a-z)"
+
+        if [ -n "$POSTFIX" ]; then
+            T=$(( $PFX_SZ + $(echo $POSTFIX | wc -c) + 2 ))
+	        TABS="$(printf '\t\t\t\t\t\t')"
+		    TABCOUNT=$(( ( 6*8 - ($T + 1) - $(echo "$NAME" | wc -c) ) / 8 ))
+		    printf "\t[%s - %s]%.*s = %s,\n" "$PFX$NAME" "$POSTFIX" "$TABCOUNT" "$TABS" "$VALUE"
+        else
+		    TABCOUNT=$(( ( 5*8 - ($PFX_SZ + 1) - $(echo "$NAME" | wc -c) ) / 8 ))
+            printf "\t[%s]%.*s = %s,\n" "$PFX$NAME" "$TABCOUNT" "$TABS" "$VALUE"
+        fi
+	done
+	echo "};"
+}
+
+trap 'rm "$OUT"' EXIT
+
+(
+	echo "#ifndef _ASM_X86_CPUFEATURES_H"
+	echo "#include <asm/cpufeatures.h>"
+	echo "#endif"
+	echo ""
+
+	dump_array "x86_cap_flags" "NCAPINTS*32" "X86_FEATURE_" "" $2
+	echo ""
+
+	dump_array "x86_bug_flags" "NBUGINTS*32" "X86_BUG_" "NCAPINTS*32" $2
+	echo ""
+
+	echo "#ifdef CONFIG_X86_VMX_FEATURE_NAMES"
+	echo "#ifndef _ASM_X86_VMXFEATURES_H"
+	echo "#include <asm/vmxfeatures.h>"
+	echo "#endif"
+	dump_array "x86_vmx_flags" "NVMXINTS*32" "VMX_FEATURE_" "" $3
+	echo "#endif /* CONFIG_X86_VMX_FEATURE_NAMES */"
+) > $OUT
+
+trap - EXIT
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
new file mode 100644
index 0000000000..e6bba12c75
--- /dev/null
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -0,0 +1,647 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * HyperV  Detection code.
+ *
+ * Copyright (C) 2010, Novell, Inc.
+ * Author : K. Y. Srinivasan <ksrinivasan@novell.com>
+ */
+
+#include <linux/types.h>
+#include <linux/time.h>
+#include <linux/clocksource.h>
+#include <linux/init.h>
+#include <linux/export.h>
+#include <linux/hardirq.h>
+#include <linux/efi.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kexec.h>
+#include <linux/i8253.h>
+#include <linux/random.h>
+#include <asm/processor.h>
+#include <asm/hypervisor.h>
+#include <asm/hyperv-tlfs.h>
+#include <asm/mshyperv.h>
+#include <asm/desc.h>
+#include <asm/idtentry.h>
+#include <asm/irq_regs.h>
+#include <asm/i8259.h>
+#include <asm/apic.h>
+#include <asm/timer.h>
+#include <asm/reboot.h>
+#include <asm/nmi.h>
+#include <clocksource/hyperv_timer.h>
+#include <asm/numa.h>
+#include <asm/svm.h>
+
+/* Is Linux running as the root partition? */
+bool hv_root_partition;
+/* Is Linux running on nested Microsoft Hypervisor */
+bool hv_nested;
+struct ms_hyperv_info ms_hyperv;
+
+/* Used in modules via hv_do_hypercall(): see arch/x86/include/asm/mshyperv.h */
+bool hyperv_paravisor_present __ro_after_init;
+EXPORT_SYMBOL_GPL(hyperv_paravisor_present);
+
+#if IS_ENABLED(CONFIG_HYPERV)
+static inline unsigned int hv_get_nested_reg(unsigned int reg)
+{
+	if (hv_is_sint_reg(reg))
+		return reg - HV_REGISTER_SINT0 + HV_REGISTER_NESTED_SINT0;
+
+	switch (reg) {
+	case HV_REGISTER_SIMP:
+		return HV_REGISTER_NESTED_SIMP;
+	case HV_REGISTER_SIEFP:
+		return HV_REGISTER_NESTED_SIEFP;
+	case HV_REGISTER_SVERSION:
+		return HV_REGISTER_NESTED_SVERSION;
+	case HV_REGISTER_SCONTROL:
+		return HV_REGISTER_NESTED_SCONTROL;
+	case HV_REGISTER_EOM:
+		return HV_REGISTER_NESTED_EOM;
+	default:
+		return reg;
+	}
+}
+
+u64 hv_get_non_nested_register(unsigned int reg)
+{
+	u64 value;
+
+	if (hv_is_synic_reg(reg) && ms_hyperv.paravisor_present)
+		hv_ivm_msr_read(reg, &value);
+	else
+		rdmsrl(reg, value);
+	return value;
+}
+EXPORT_SYMBOL_GPL(hv_get_non_nested_register);
+
+void hv_set_non_nested_register(unsigned int reg, u64 value)
+{
+	if (hv_is_synic_reg(reg) && ms_hyperv.paravisor_present) {
+		hv_ivm_msr_write(reg, value);
+
+		/* Write proxy bit via wrmsl instruction */
+		if (hv_is_sint_reg(reg))
+			wrmsrl(reg, value | 1 << 20);
+	} else {
+		wrmsrl(reg, value);
+	}
+}
+EXPORT_SYMBOL_GPL(hv_set_non_nested_register);
+
+u64 hv_get_register(unsigned int reg)
+{
+	if (hv_nested)
+		reg = hv_get_nested_reg(reg);
+
+	return hv_get_non_nested_register(reg);
+}
+EXPORT_SYMBOL_GPL(hv_get_register);
+
+void hv_set_register(unsigned int reg, u64 value)
+{
+	if (hv_nested)
+		reg = hv_get_nested_reg(reg);
+
+	hv_set_non_nested_register(reg, value);
+}
+EXPORT_SYMBOL_GPL(hv_set_register);
+
+static void (*vmbus_handler)(void);
+static void (*hv_stimer0_handler)(void);
+static void (*hv_kexec_handler)(void);
+static void (*hv_crash_handler)(struct pt_regs *regs);
+
+DEFINE_IDTENTRY_SYSVEC(sysvec_hyperv_callback)
+{
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
+	inc_irq_stat(irq_hv_callback_count);
+	if (vmbus_handler)
+		vmbus_handler();
+
+	if (ms_hyperv.hints & HV_DEPRECATING_AEOI_RECOMMENDED)
+		apic_eoi();
+
+	set_irq_regs(old_regs);
+}
+
+void hv_setup_vmbus_handler(void (*handler)(void))
+{
+	vmbus_handler = handler;
+}
+
+void hv_remove_vmbus_handler(void)
+{
+	/* We have no way to deallocate the interrupt gate */
+	vmbus_handler = NULL;
+}
+
+/*
+ * Routines to do per-architecture handling of stimer0
+ * interrupts when in Direct Mode
+ */
+DEFINE_IDTENTRY_SYSVEC(sysvec_hyperv_stimer0)
+{
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
+	inc_irq_stat(hyperv_stimer0_count);
+	if (hv_stimer0_handler)
+		hv_stimer0_handler();
+	add_interrupt_randomness(HYPERV_STIMER0_VECTOR);
+	apic_eoi();
+
+	set_irq_regs(old_regs);
+}
+
+/* For x86/x64, override weak placeholders in hyperv_timer.c */
+void hv_setup_stimer0_handler(void (*handler)(void))
+{
+	hv_stimer0_handler = handler;
+}
+
+void hv_remove_stimer0_handler(void)
+{
+	/* We have no way to deallocate the interrupt gate */
+	hv_stimer0_handler = NULL;
+}
+
+void hv_setup_kexec_handler(void (*handler)(void))
+{
+	hv_kexec_handler = handler;
+}
+
+void hv_remove_kexec_handler(void)
+{
+	hv_kexec_handler = NULL;
+}
+
+void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs))
+{
+	hv_crash_handler = handler;
+}
+
+void hv_remove_crash_handler(void)
+{
+	hv_crash_handler = NULL;
+}
+
+#ifdef CONFIG_KEXEC_CORE
+static void hv_machine_shutdown(void)
+{
+	if (kexec_in_progress && hv_kexec_handler)
+		hv_kexec_handler();
+
+	/*
+	 * Call hv_cpu_die() on all the CPUs, otherwise later the hypervisor
+	 * corrupts the old VP Assist Pages and can crash the kexec kernel.
+	 */
+	if (kexec_in_progress && hyperv_init_cpuhp > 0)
+		cpuhp_remove_state(hyperv_init_cpuhp);
+
+	/* The function calls stop_other_cpus(). */
+	native_machine_shutdown();
+
+	/* Disable the hypercall page when there is only 1 active CPU. */
+	if (kexec_in_progress)
+		hyperv_cleanup();
+}
+
+static void hv_machine_crash_shutdown(struct pt_regs *regs)
+{
+	if (hv_crash_handler)
+		hv_crash_handler(regs);
+
+	/* The function calls crash_smp_send_stop(). */
+	native_machine_crash_shutdown(regs);
+
+	/* Disable the hypercall page when there is only 1 active CPU. */
+	hyperv_cleanup();
+}
+#endif /* CONFIG_KEXEC_CORE */
+#endif /* CONFIG_HYPERV */
+
+static uint32_t  __init ms_hyperv_platform(void)
+{
+	u32 eax;
+	u32 hyp_signature[3];
+
+	if (!boot_cpu_has(X86_FEATURE_HYPERVISOR))
+		return 0;
+
+	cpuid(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS,
+	      &eax, &hyp_signature[0], &hyp_signature[1], &hyp_signature[2]);
+
+	if (eax < HYPERV_CPUID_MIN || eax > HYPERV_CPUID_MAX ||
+	    memcmp("Microsoft Hv", hyp_signature, 12))
+		return 0;
+
+	/* HYPERCALL and VP_INDEX MSRs are mandatory for all features. */
+	eax = cpuid_eax(HYPERV_CPUID_FEATURES);
+	if (!(eax & HV_MSR_HYPERCALL_AVAILABLE)) {
+		pr_warn("x86/hyperv: HYPERCALL MSR not available.\n");
+		return 0;
+	}
+	if (!(eax & HV_MSR_VP_INDEX_AVAILABLE)) {
+		pr_warn("x86/hyperv: VP_INDEX MSR not available.\n");
+		return 0;
+	}
+
+	return HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS;
+}
+
+#ifdef CONFIG_X86_LOCAL_APIC
+/*
+ * Prior to WS2016 Debug-VM sends NMIs to all CPUs which makes
+ * it difficult to process CHANNELMSG_UNLOAD in case of crash. Handle
+ * unknown NMI on the first CPU which gets it.
+ */
+static int hv_nmi_unknown(unsigned int val, struct pt_regs *regs)
+{
+	static atomic_t nmi_cpu = ATOMIC_INIT(-1);
+
+	if (!unknown_nmi_panic)
+		return NMI_DONE;
+
+	if (atomic_cmpxchg(&nmi_cpu, -1, raw_smp_processor_id()) != -1)
+		return NMI_HANDLED;
+
+	return NMI_DONE;
+}
+#endif
+
+static unsigned long hv_get_tsc_khz(void)
+{
+	unsigned long freq;
+
+	rdmsrl(HV_X64_MSR_TSC_FREQUENCY, freq);
+
+	return freq / 1000;
+}
+
+#if defined(CONFIG_SMP) && IS_ENABLED(CONFIG_HYPERV)
+static void __init hv_smp_prepare_boot_cpu(void)
+{
+	native_smp_prepare_boot_cpu();
+#if defined(CONFIG_X86_64) && defined(CONFIG_PARAVIRT_SPINLOCKS)
+	hv_init_spinlocks();
+#endif
+}
+
+static void __init hv_smp_prepare_cpus(unsigned int max_cpus)
+{
+#ifdef CONFIG_X86_64
+	int i;
+	int ret;
+#endif
+
+	native_smp_prepare_cpus(max_cpus);
+
+	/*
+	 *  Override wakeup_secondary_cpu_64 callback for SEV-SNP
+	 *  enlightened guest.
+	 */
+	if (!ms_hyperv.paravisor_present && hv_isolation_type_snp()) {
+		apic->wakeup_secondary_cpu_64 = hv_snp_boot_ap;
+		return;
+	}
+
+#ifdef CONFIG_X86_64
+	for_each_present_cpu(i) {
+		if (i == 0)
+			continue;
+		ret = hv_call_add_logical_proc(numa_cpu_node(i), i, cpu_physical_id(i));
+		BUG_ON(ret);
+	}
+
+	for_each_present_cpu(i) {
+		if (i == 0)
+			continue;
+		ret = hv_call_create_vp(numa_cpu_node(i), hv_current_partition_id, i, i);
+		BUG_ON(ret);
+	}
+#endif
+}
+#endif
+
+/*
+ * When a fully enlightened TDX VM runs on Hyper-V, the firmware sets the
+ * HW_REDUCED flag: refer to acpi_tb_create_local_fadt(). Consequently ttyS0
+ * interrupts can't work because request_irq() -> ... -> irq_to_desc() returns
+ * NULL for ttyS0. This happens because mp_config_acpi_legacy_irqs() sees a
+ * nr_legacy_irqs() of 0, so it doesn't initialize the array 'mp_irqs[]', and
+ * later setup_IO_APIC_irqs() -> find_irq_entry() fails to find the legacy irqs
+ * from the array and hence doesn't create the necessary irq description info.
+ *
+ * Clone arch/x86/kernel/acpi/boot.c: acpi_generic_reduced_hw_init() here,
+ * except don't change 'legacy_pic', which keeps its default value
+ * 'default_legacy_pic'. This way, mp_config_acpi_legacy_irqs() sees a non-zero
+ * nr_legacy_irqs() and eventually serial console interrupts works properly.
+ */
+static void __init reduced_hw_init(void)
+{
+	x86_init.timers.timer_init	= x86_init_noop;
+	x86_init.irqs.pre_vector_init	= x86_init_noop;
+}
+
+static void __init ms_hyperv_init_platform(void)
+{
+	int hv_max_functions_eax;
+	int hv_host_info_eax;
+	int hv_host_info_ebx;
+	int hv_host_info_ecx;
+	int hv_host_info_edx;
+
+#ifdef CONFIG_PARAVIRT
+	pv_info.name = "Hyper-V";
+#endif
+
+	/*
+	 * Extract the features and hints
+	 */
+	ms_hyperv.features = cpuid_eax(HYPERV_CPUID_FEATURES);
+	ms_hyperv.priv_high = cpuid_ebx(HYPERV_CPUID_FEATURES);
+	ms_hyperv.misc_features = cpuid_edx(HYPERV_CPUID_FEATURES);
+	ms_hyperv.hints    = cpuid_eax(HYPERV_CPUID_ENLIGHTMENT_INFO);
+
+	hv_max_functions_eax = cpuid_eax(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS);
+
+	pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, hints 0x%x, misc 0x%x\n",
+		ms_hyperv.features, ms_hyperv.priv_high, ms_hyperv.hints,
+		ms_hyperv.misc_features);
+
+	ms_hyperv.max_vp_index = cpuid_eax(HYPERV_CPUID_IMPLEMENT_LIMITS);
+	ms_hyperv.max_lp_index = cpuid_ebx(HYPERV_CPUID_IMPLEMENT_LIMITS);
+
+	pr_debug("Hyper-V: max %u virtual processors, %u logical processors\n",
+		 ms_hyperv.max_vp_index, ms_hyperv.max_lp_index);
+
+	/*
+	 * Check CPU management privilege.
+	 *
+	 * To mirror what Windows does we should extract CPU management
+	 * features and use the ReservedIdentityBit to detect if Linux is the
+	 * root partition. But that requires negotiating CPU management
+	 * interface (a process to be finalized). For now, use the privilege
+	 * flag as the indicator for running as root.
+	 *
+	 * Hyper-V should never specify running as root and as a Confidential
+	 * VM. But to protect against a compromised/malicious Hyper-V trying
+	 * to exploit root behavior to expose Confidential VM memory, ignore
+	 * the root partition setting if also a Confidential VM.
+	 */
+	if ((ms_hyperv.priv_high & HV_CPU_MANAGEMENT) &&
+	    !(ms_hyperv.priv_high & HV_ISOLATION)) {
+		hv_root_partition = true;
+		pr_info("Hyper-V: running as root partition\n");
+	}
+
+	if (ms_hyperv.hints & HV_X64_HYPERV_NESTED) {
+		hv_nested = true;
+		pr_info("Hyper-V: running on a nested hypervisor\n");
+	}
+
+	/*
+	 * Extract host information.
+	 */
+	if (hv_max_functions_eax >= HYPERV_CPUID_VERSION) {
+		hv_host_info_eax = cpuid_eax(HYPERV_CPUID_VERSION);
+		hv_host_info_ebx = cpuid_ebx(HYPERV_CPUID_VERSION);
+		hv_host_info_ecx = cpuid_ecx(HYPERV_CPUID_VERSION);
+		hv_host_info_edx = cpuid_edx(HYPERV_CPUID_VERSION);
+
+		pr_info("Hyper-V: Host Build %d.%d.%d.%d-%d-%d\n",
+			hv_host_info_ebx >> 16, hv_host_info_ebx & 0xFFFF,
+			hv_host_info_eax, hv_host_info_edx & 0xFFFFFF,
+			hv_host_info_ecx, hv_host_info_edx >> 24);
+	}
+
+	if (ms_hyperv.features & HV_ACCESS_FREQUENCY_MSRS &&
+	    ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE) {
+		x86_platform.calibrate_tsc = hv_get_tsc_khz;
+		x86_platform.calibrate_cpu = hv_get_tsc_khz;
+	}
+
+	if (ms_hyperv.priv_high & HV_ISOLATION) {
+		ms_hyperv.isolation_config_a = cpuid_eax(HYPERV_CPUID_ISOLATION_CONFIG);
+		ms_hyperv.isolation_config_b = cpuid_ebx(HYPERV_CPUID_ISOLATION_CONFIG);
+
+		if (ms_hyperv.shared_gpa_boundary_active)
+			ms_hyperv.shared_gpa_boundary =
+				BIT_ULL(ms_hyperv.shared_gpa_boundary_bits);
+
+		hyperv_paravisor_present = !!ms_hyperv.paravisor_present;
+
+		pr_info("Hyper-V: Isolation Config: Group A 0x%x, Group B 0x%x\n",
+			ms_hyperv.isolation_config_a, ms_hyperv.isolation_config_b);
+
+
+		if (hv_get_isolation_type() == HV_ISOLATION_TYPE_SNP) {
+			static_branch_enable(&isolation_type_snp);
+		} else if (hv_get_isolation_type() == HV_ISOLATION_TYPE_TDX) {
+			static_branch_enable(&isolation_type_tdx);
+
+			/* A TDX VM must use x2APIC and doesn't use lazy EOI. */
+			ms_hyperv.hints &= ~HV_X64_APIC_ACCESS_RECOMMENDED;
+
+			if (!ms_hyperv.paravisor_present) {
+				/* To be supported: more work is required.  */
+				ms_hyperv.features &= ~HV_MSR_REFERENCE_TSC_AVAILABLE;
+
+				/* HV_REGISTER_CRASH_CTL is unsupported. */
+				ms_hyperv.misc_features &= ~HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
+
+				/* Don't trust Hyper-V's TLB-flushing hypercalls. */
+				ms_hyperv.hints &= ~HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
+
+				x86_init.acpi.reduced_hw_early_init = reduced_hw_init;
+			}
+		}
+	}
+
+	if (hv_max_functions_eax >= HYPERV_CPUID_NESTED_FEATURES) {
+		ms_hyperv.nested_features =
+			cpuid_eax(HYPERV_CPUID_NESTED_FEATURES);
+		pr_info("Hyper-V: Nested features: 0x%x\n",
+			ms_hyperv.nested_features);
+	}
+
+#ifdef CONFIG_X86_LOCAL_APIC
+	if (ms_hyperv.features & HV_ACCESS_FREQUENCY_MSRS &&
+	    ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE) {
+		/*
+		 * Get the APIC frequency.
+		 */
+		u64	hv_lapic_frequency;
+
+		rdmsrl(HV_X64_MSR_APIC_FREQUENCY, hv_lapic_frequency);
+		hv_lapic_frequency = div_u64(hv_lapic_frequency, HZ);
+		lapic_timer_period = hv_lapic_frequency;
+		pr_info("Hyper-V: LAPIC Timer Frequency: %#x\n",
+			lapic_timer_period);
+	}
+
+	register_nmi_handler(NMI_UNKNOWN, hv_nmi_unknown, NMI_FLAG_FIRST,
+			     "hv_nmi_unknown");
+#endif
+
+#ifdef CONFIG_X86_IO_APIC
+	no_timer_check = 1;
+#endif
+
+#if IS_ENABLED(CONFIG_HYPERV) && defined(CONFIG_KEXEC_CORE)
+	machine_ops.shutdown = hv_machine_shutdown;
+	machine_ops.crash_shutdown = hv_machine_crash_shutdown;
+#endif
+	if (ms_hyperv.features & HV_ACCESS_TSC_INVARIANT) {
+		/*
+		 * Writing to synthetic MSR 0x40000118 updates/changes the
+		 * guest visible CPUIDs. Setting bit 0 of this MSR  enables
+		 * guests to report invariant TSC feature through CPUID
+		 * instruction, CPUID 0x800000007/EDX, bit 8. See code in
+		 * early_init_intel() where this bit is examined. The
+		 * setting of this MSR bit should happen before init_intel()
+		 * is called.
+		 */
+		wrmsrl(HV_X64_MSR_TSC_INVARIANT_CONTROL, HV_EXPOSE_INVARIANT_TSC);
+		setup_force_cpu_cap(X86_FEATURE_TSC_RELIABLE);
+	}
+
+	/*
+	 * Generation 2 instances don't support reading the NMI status from
+	 * 0x61 port.
+	 */
+	if (efi_enabled(EFI_BOOT))
+		x86_platform.get_nmi_reason = hv_get_nmi_reason;
+
+	/*
+	 * Hyper-V VMs have a PIT emulation quirk such that zeroing the
+	 * counter register during PIT shutdown restarts the PIT. So it
+	 * continues to interrupt @18.2 HZ. Setting i8253_clear_counter
+	 * to false tells pit_shutdown() not to zero the counter so that
+	 * the PIT really is shutdown. Generation 2 VMs don't have a PIT,
+	 * and setting this value has no effect.
+	 */
+	i8253_clear_counter_on_shutdown = false;
+
+#if IS_ENABLED(CONFIG_HYPERV)
+	if ((hv_get_isolation_type() == HV_ISOLATION_TYPE_VBS) ||
+	    ms_hyperv.paravisor_present)
+		hv_vtom_init();
+	/*
+	 * Setup the hook to get control post apic initialization.
+	 */
+	x86_platform.apic_post_init = hyperv_init;
+	hyperv_setup_mmu_ops();
+	/* Setup the IDT for hypervisor callback */
+	alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_hyperv_callback);
+
+	/* Setup the IDT for reenlightenment notifications */
+	if (ms_hyperv.features & HV_ACCESS_REENLIGHTENMENT) {
+		alloc_intr_gate(HYPERV_REENLIGHTENMENT_VECTOR,
+				asm_sysvec_hyperv_reenlightenment);
+	}
+
+	/* Setup the IDT for stimer0 */
+	if (ms_hyperv.misc_features & HV_STIMER_DIRECT_MODE_AVAILABLE) {
+		alloc_intr_gate(HYPERV_STIMER0_VECTOR,
+				asm_sysvec_hyperv_stimer0);
+	}
+
+# ifdef CONFIG_SMP
+	smp_ops.smp_prepare_boot_cpu = hv_smp_prepare_boot_cpu;
+	if (hv_root_partition ||
+	    (!ms_hyperv.paravisor_present && hv_isolation_type_snp()))
+		smp_ops.smp_prepare_cpus = hv_smp_prepare_cpus;
+# endif
+
+	/*
+	 * Hyper-V doesn't provide irq remapping for IO-APIC. To enable x2apic,
+	 * set x2apic destination mode to physical mode when x2apic is available
+	 * and Hyper-V IOMMU driver makes sure cpus assigned with IO-APIC irqs
+	 * have 8-bit APIC id.
+	 */
+# ifdef CONFIG_X86_X2APIC
+	if (x2apic_supported())
+		x2apic_phys = 1;
+# endif
+
+	/* Register Hyper-V specific clocksource */
+	hv_init_clocksource();
+	hv_vtl_init_platform();
+#endif
+	/*
+	 * TSC should be marked as unstable only after Hyper-V
+	 * clocksource has been initialized. This ensures that the
+	 * stability of the sched_clock is not altered.
+	 */
+	if (!(ms_hyperv.features & HV_ACCESS_TSC_INVARIANT))
+		mark_tsc_unstable("running on Hyper-V");
+
+	hardlockup_detector_disable();
+}
+
+static bool __init ms_hyperv_x2apic_available(void)
+{
+	return x2apic_supported();
+}
+
+/*
+ * If ms_hyperv_msi_ext_dest_id() returns true, hyperv_prepare_irq_remapping()
+ * returns -ENODEV and the Hyper-V IOMMU driver is not used; instead, the
+ * generic support of the 15-bit APIC ID is used: see __irq_msi_compose_msg().
+ *
+ * Note: for a VM on Hyper-V, the I/O-APIC is the only device which
+ * (logically) generates MSIs directly to the system APIC irq domain.
+ * There is no HPET, and PCI MSI/MSI-X interrupts are remapped by the
+ * pci-hyperv host bridge.
+ *
+ * Note: for a Hyper-V root partition, this will always return false.
+ * The hypervisor doesn't expose these HYPERV_CPUID_VIRT_STACK_* cpuids by
+ * default, they are implemented as intercepts by the Windows Hyper-V stack.
+ * Even a nested root partition (L2 root) will not get them because the
+ * nested (L1) hypervisor filters them out.
+ */
+static bool __init ms_hyperv_msi_ext_dest_id(void)
+{
+	u32 eax;
+
+	eax = cpuid_eax(HYPERV_CPUID_VIRT_STACK_INTERFACE);
+	if (eax != HYPERV_VS_INTERFACE_EAX_SIGNATURE)
+		return false;
+
+	eax = cpuid_eax(HYPERV_CPUID_VIRT_STACK_PROPERTIES);
+	return eax & HYPERV_VS_PROPERTIES_EAX_EXTENDED_IOAPIC_RTE;
+}
+
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+static void hv_sev_es_hcall_prepare(struct ghcb *ghcb, struct pt_regs *regs)
+{
+	/* RAX and CPL are already in the GHCB */
+	ghcb_set_rcx(ghcb, regs->cx);
+	ghcb_set_rdx(ghcb, regs->dx);
+	ghcb_set_r8(ghcb, regs->r8);
+}
+
+static bool hv_sev_es_hcall_finish(struct ghcb *ghcb, struct pt_regs *regs)
+{
+	/* No checking of the return state needed */
+	return true;
+}
+#endif
+
+const __initconst struct hypervisor_x86 x86_hyper_ms_hyperv = {
+	.name			= "Microsoft Hyper-V",
+	.detect			= ms_hyperv_platform,
+	.type			= X86_HYPER_MS_HYPERV,
+	.init.x2apic_available	= ms_hyperv_x2apic_available,
+	.init.msi_ext_dest_id	= ms_hyperv_msi_ext_dest_id,
+	.init.init_platform	= ms_hyperv_init_platform,
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+	.runtime.sev_es_hcall_prepare = hv_sev_es_hcall_prepare,
+	.runtime.sev_es_hcall_finish = hv_sev_es_hcall_finish,
+#endif
+};
diff --git a/arch/x86/kernel/cpu/mtrr/Makefile b/arch/x86/kernel/cpu/mtrr/Makefile
new file mode 100644
index 0000000000..aee4bc5ad4
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-y		:= mtrr.o if.o generic.o cleanup.o
+obj-$(CONFIG_X86_32) += amd.o cyrix.o centaur.o legacy.o
+
diff --git a/arch/x86/kernel/cpu/mtrr/amd.c b/arch/x86/kernel/cpu/mtrr/amd.c
new file mode 100644
index 0000000000..ef3e8e42b7
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/amd.c
@@ -0,0 +1,119 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+
+#include "mtrr.h"
+
+static void
+amd_get_mtrr(unsigned int reg, unsigned long *base,
+	     unsigned long *size, mtrr_type *type)
+{
+	unsigned long low, high;
+
+	rdmsr(MSR_K6_UWCCR, low, high);
+	/* Upper dword is region 1, lower is region 0 */
+	if (reg == 1)
+		low = high;
+	/* The base masks off on the right alignment */
+	*base = (low & 0xFFFE0000) >> PAGE_SHIFT;
+	*type = 0;
+	if (low & 1)
+		*type = MTRR_TYPE_UNCACHABLE;
+	if (low & 2)
+		*type = MTRR_TYPE_WRCOMB;
+	if (!(low & 3)) {
+		*size = 0;
+		return;
+	}
+	/*
+	 * This needs a little explaining. The size is stored as an
+	 * inverted mask of bits of 128K granularity 15 bits long offset
+	 * 2 bits.
+	 *
+	 * So to get a size we do invert the mask and add 1 to the lowest
+	 * mask bit (4 as its 2 bits in). This gives us a size we then shift
+	 * to turn into 128K blocks.
+	 *
+	 * eg              111 1111 1111 1100      is 512K
+	 *
+	 * invert          000 0000 0000 0011
+	 * +1              000 0000 0000 0100
+	 * *128K   ...
+	 */
+	low = (~low) & 0x1FFFC;
+	*size = (low + 4) << (15 - PAGE_SHIFT);
+}
+
+/**
+ * amd_set_mtrr - Set variable MTRR register on the local CPU.
+ *
+ * @reg The register to set.
+ * @base The base address of the region.
+ * @size The size of the region. If this is 0 the region is disabled.
+ * @type The type of the region.
+ *
+ * Returns nothing.
+ */
+static void
+amd_set_mtrr(unsigned int reg, unsigned long base, unsigned long size, mtrr_type type)
+{
+	u32 regs[2];
+
+	/*
+	 * Low is MTRR0, High MTRR 1
+	 */
+	rdmsr(MSR_K6_UWCCR, regs[0], regs[1]);
+	/*
+	 * Blank to disable
+	 */
+	if (size == 0) {
+		regs[reg] = 0;
+	} else {
+		/*
+		 * Set the register to the base, the type (off by one) and an
+		 * inverted bitmask of the size The size is the only odd
+		 * bit. We are fed say 512K We invert this and we get 111 1111
+		 * 1111 1011 but if you subtract one and invert you get the
+		 * desired 111 1111 1111 1100 mask
+		 *
+		 *  But ~(x - 1) == ~x + 1 == -x. Two's complement rocks!
+		 */
+		regs[reg] = (-size >> (15 - PAGE_SHIFT) & 0x0001FFFC)
+		    | (base << PAGE_SHIFT) | (type + 1);
+	}
+
+	/*
+	 * The writeback rule is quite specific. See the manual. Its
+	 * disable local interrupts, write back the cache, set the mtrr
+	 */
+	wbinvd();
+	wrmsr(MSR_K6_UWCCR, regs[0], regs[1]);
+}
+
+static int
+amd_validate_add_page(unsigned long base, unsigned long size, unsigned int type)
+{
+	/*
+	 * Apply the K6 block alignment and size rules
+	 * In order
+	 * o Uncached or gathering only
+	 * o 128K or bigger block
+	 * o Power of 2 block
+	 * o base suitably aligned to the power
+	 */
+	if (type > MTRR_TYPE_WRCOMB || size < (1 << (17 - PAGE_SHIFT))
+	    || (size & ~(size - 1)) - size || (base & (size - 1)))
+		return -EINVAL;
+	return 0;
+}
+
+const struct mtrr_ops amd_mtrr_ops = {
+	.var_regs          = 2,
+	.set               = amd_set_mtrr,
+	.get               = amd_get_mtrr,
+	.get_free_region   = generic_get_free_region,
+	.validate_add_page = amd_validate_add_page,
+	.have_wrcomb       = positive_have_wrcomb,
+};
diff --git a/arch/x86/kernel/cpu/mtrr/centaur.c b/arch/x86/kernel/cpu/mtrr/centaur.c
new file mode 100644
index 0000000000..6f6c3ae929
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/centaur.c
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <linux/mm.h>
+
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+
+#include "mtrr.h"
+
+static struct {
+	unsigned long high;
+	unsigned long low;
+} centaur_mcr[8];
+
+static u8 centaur_mcr_reserved;
+static u8 centaur_mcr_type;	/* 0 for winchip, 1 for winchip2 */
+
+/**
+ * centaur_get_free_region - Get a free MTRR.
+ *
+ * @base: The starting (base) address of the region.
+ * @size: The size (in bytes) of the region.
+ *
+ * Returns: the index of the region on success, else -1 on error.
+ */
+static int
+centaur_get_free_region(unsigned long base, unsigned long size, int replace_reg)
+{
+	unsigned long lbase, lsize;
+	mtrr_type ltype;
+	int i, max;
+
+	max = num_var_ranges;
+	if (replace_reg >= 0 && replace_reg < max)
+		return replace_reg;
+
+	for (i = 0; i < max; ++i) {
+		if (centaur_mcr_reserved & (1 << i))
+			continue;
+		mtrr_if->get(i, &lbase, &lsize, &ltype);
+		if (lsize == 0)
+			return i;
+	}
+
+	return -ENOSPC;
+}
+
+static void
+centaur_get_mcr(unsigned int reg, unsigned long *base,
+		unsigned long *size, mtrr_type * type)
+{
+	*base = centaur_mcr[reg].high >> PAGE_SHIFT;
+	*size = -(centaur_mcr[reg].low & 0xfffff000) >> PAGE_SHIFT;
+	*type = MTRR_TYPE_WRCOMB;		/* write-combining  */
+
+	if (centaur_mcr_type == 1 && ((centaur_mcr[reg].low & 31) & 2))
+		*type = MTRR_TYPE_UNCACHABLE;
+	if (centaur_mcr_type == 1 && (centaur_mcr[reg].low & 31) == 25)
+		*type = MTRR_TYPE_WRBACK;
+	if (centaur_mcr_type == 0 && (centaur_mcr[reg].low & 31) == 31)
+		*type = MTRR_TYPE_WRBACK;
+}
+
+static void
+centaur_set_mcr(unsigned int reg, unsigned long base,
+		unsigned long size, mtrr_type type)
+{
+	unsigned long low, high;
+
+	if (size == 0) {
+		/* Disable */
+		high = low = 0;
+	} else {
+		high = base << PAGE_SHIFT;
+		if (centaur_mcr_type == 0) {
+			/* Only support write-combining... */
+			low = -size << PAGE_SHIFT | 0x1f;
+		} else {
+			if (type == MTRR_TYPE_UNCACHABLE)
+				low = -size << PAGE_SHIFT | 0x02; /* NC */
+			else
+				low = -size << PAGE_SHIFT | 0x09; /* WWO, WC */
+		}
+	}
+	centaur_mcr[reg].high = high;
+	centaur_mcr[reg].low = low;
+	wrmsr(MSR_IDT_MCR0 + reg, low, high);
+}
+
+static int
+centaur_validate_add_page(unsigned long base, unsigned long size, unsigned int type)
+{
+	/*
+	 * FIXME: Winchip2 supports uncached
+	 */
+	if (type != MTRR_TYPE_WRCOMB &&
+	    (centaur_mcr_type == 0 || type != MTRR_TYPE_UNCACHABLE)) {
+		pr_warn("mtrr: only write-combining%s supported\n",
+			   centaur_mcr_type ? " and uncacheable are" : " is");
+		return -EINVAL;
+	}
+	return 0;
+}
+
+const struct mtrr_ops centaur_mtrr_ops = {
+	.var_regs          = 8,
+	.set               = centaur_set_mcr,
+	.get               = centaur_get_mcr,
+	.get_free_region   = centaur_get_free_region,
+	.validate_add_page = centaur_validate_add_page,
+	.have_wrcomb       = positive_have_wrcomb,
+};
diff --git a/arch/x86/kernel/cpu/mtrr/cleanup.c b/arch/x86/kernel/cpu/mtrr/cleanup.c
new file mode 100644
index 0000000000..18cf79d6e2
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/cleanup.c
@@ -0,0 +1,980 @@
+/*
+ * MTRR (Memory Type Range Register) cleanup
+ *
+ *  Copyright (C) 2009 Yinghai Lu
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the Free
+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/smp.h>
+#include <linux/cpu.h>
+#include <linux/mutex.h>
+#include <linux/uaccess.h>
+#include <linux/kvm_para.h>
+#include <linux/range.h>
+
+#include <asm/processor.h>
+#include <asm/e820/api.h>
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+
+#include "mtrr.h"
+
+struct var_mtrr_range_state {
+	unsigned long	base_pfn;
+	unsigned long	size_pfn;
+	mtrr_type	type;
+};
+
+struct var_mtrr_state {
+	unsigned long	range_startk;
+	unsigned long	range_sizek;
+	unsigned long	chunk_sizek;
+	unsigned long	gran_sizek;
+	unsigned int	reg;
+};
+
+/* Should be related to MTRR_VAR_RANGES nums */
+#define RANGE_NUM				256
+
+static struct range __initdata		range[RANGE_NUM];
+static int __initdata				nr_range;
+
+static struct var_mtrr_range_state __initdata	range_state[RANGE_NUM];
+
+#define BIOS_BUG_MSG \
+	"WARNING: BIOS bug: VAR MTRR %d contains strange UC entry under 1M, check with your system vendor!\n"
+
+static int __init
+x86_get_mtrr_mem_range(struct range *range, int nr_range,
+		       unsigned long extra_remove_base,
+		       unsigned long extra_remove_size)
+{
+	unsigned long base, size;
+	mtrr_type type;
+	int i;
+
+	for (i = 0; i < num_var_ranges; i++) {
+		type = range_state[i].type;
+		if (type != MTRR_TYPE_WRBACK)
+			continue;
+		base = range_state[i].base_pfn;
+		size = range_state[i].size_pfn;
+		nr_range = add_range_with_merge(range, RANGE_NUM, nr_range,
+						base, base + size);
+	}
+
+	Dprintk("After WB checking\n");
+	for (i = 0; i < nr_range; i++)
+		Dprintk("MTRR MAP PFN: %016llx - %016llx\n",
+			 range[i].start, range[i].end);
+
+	/* Take out UC ranges: */
+	for (i = 0; i < num_var_ranges; i++) {
+		type = range_state[i].type;
+		if (type != MTRR_TYPE_UNCACHABLE &&
+		    type != MTRR_TYPE_WRPROT)
+			continue;
+		size = range_state[i].size_pfn;
+		if (!size)
+			continue;
+		base = range_state[i].base_pfn;
+		if (base < (1<<(20-PAGE_SHIFT)) && mtrr_state.have_fixed &&
+		    (mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED) &&
+		    (mtrr_state.enabled & MTRR_STATE_MTRR_FIXED_ENABLED)) {
+			/* Var MTRR contains UC entry below 1M? Skip it: */
+			pr_warn(BIOS_BUG_MSG, i);
+			if (base + size <= (1<<(20-PAGE_SHIFT)))
+				continue;
+			size -= (1<<(20-PAGE_SHIFT)) - base;
+			base = 1<<(20-PAGE_SHIFT);
+		}
+		subtract_range(range, RANGE_NUM, base, base + size);
+	}
+	if (extra_remove_size)
+		subtract_range(range, RANGE_NUM, extra_remove_base,
+				 extra_remove_base + extra_remove_size);
+
+	Dprintk("After UC checking\n");
+	for (i = 0; i < RANGE_NUM; i++) {
+		if (!range[i].end)
+			continue;
+
+		Dprintk("MTRR MAP PFN: %016llx - %016llx\n",
+			 range[i].start, range[i].end);
+	}
+
+	/* sort the ranges */
+	nr_range = clean_sort_range(range, RANGE_NUM);
+
+	Dprintk("After sorting\n");
+	for (i = 0; i < nr_range; i++)
+		Dprintk("MTRR MAP PFN: %016llx - %016llx\n",
+			range[i].start, range[i].end);
+
+	return nr_range;
+}
+
+#ifdef CONFIG_MTRR_SANITIZER
+
+static unsigned long __init sum_ranges(struct range *range, int nr_range)
+{
+	unsigned long sum = 0;
+	int i;
+
+	for (i = 0; i < nr_range; i++)
+		sum += range[i].end - range[i].start;
+
+	return sum;
+}
+
+static int enable_mtrr_cleanup __initdata =
+	CONFIG_MTRR_SANITIZER_ENABLE_DEFAULT;
+
+static int __init disable_mtrr_cleanup_setup(char *str)
+{
+	enable_mtrr_cleanup = 0;
+	return 0;
+}
+early_param("disable_mtrr_cleanup", disable_mtrr_cleanup_setup);
+
+static int __init enable_mtrr_cleanup_setup(char *str)
+{
+	enable_mtrr_cleanup = 1;
+	return 0;
+}
+early_param("enable_mtrr_cleanup", enable_mtrr_cleanup_setup);
+
+static void __init
+set_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek,
+	     unsigned char type)
+{
+	u32 base_lo, base_hi, mask_lo, mask_hi;
+	u64 base, mask;
+
+	if (!sizek) {
+		fill_mtrr_var_range(reg, 0, 0, 0, 0);
+		return;
+	}
+
+	mask = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
+	mask &= ~((((u64)sizek) << 10) - 1);
+
+	base = ((u64)basek) << 10;
+
+	base |= type;
+	mask |= 0x800;
+
+	base_lo = base & ((1ULL<<32) - 1);
+	base_hi = base >> 32;
+
+	mask_lo = mask & ((1ULL<<32) - 1);
+	mask_hi = mask >> 32;
+
+	fill_mtrr_var_range(reg, base_lo, base_hi, mask_lo, mask_hi);
+}
+
+static void __init
+save_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek,
+	      unsigned char type)
+{
+	range_state[reg].base_pfn = basek >> (PAGE_SHIFT - 10);
+	range_state[reg].size_pfn = sizek >> (PAGE_SHIFT - 10);
+	range_state[reg].type = type;
+}
+
+static void __init set_var_mtrr_all(void)
+{
+	unsigned long basek, sizek;
+	unsigned char type;
+	unsigned int reg;
+
+	for (reg = 0; reg < num_var_ranges; reg++) {
+		basek = range_state[reg].base_pfn << (PAGE_SHIFT - 10);
+		sizek = range_state[reg].size_pfn << (PAGE_SHIFT - 10);
+		type = range_state[reg].type;
+
+		set_var_mtrr(reg, basek, sizek, type);
+	}
+}
+
+static unsigned long to_size_factor(unsigned long sizek, char *factorp)
+{
+	unsigned long base = sizek;
+	char factor;
+
+	if (base & ((1<<10) - 1)) {
+		/* Not MB-aligned: */
+		factor = 'K';
+	} else if (base & ((1<<20) - 1)) {
+		factor = 'M';
+		base >>= 10;
+	} else {
+		factor = 'G';
+		base >>= 20;
+	}
+
+	*factorp = factor;
+
+	return base;
+}
+
+static unsigned int __init
+range_to_mtrr(unsigned int reg, unsigned long range_startk,
+	      unsigned long range_sizek, unsigned char type)
+{
+	if (!range_sizek || (reg >= num_var_ranges))
+		return reg;
+
+	while (range_sizek) {
+		unsigned long max_align, align;
+		unsigned long sizek;
+
+		/* Compute the maximum size with which we can make a range: */
+		if (range_startk)
+			max_align = __ffs(range_startk);
+		else
+			max_align = BITS_PER_LONG - 1;
+
+		align = __fls(range_sizek);
+		if (align > max_align)
+			align = max_align;
+
+		sizek = 1UL << align;
+		if (mtrr_debug) {
+			char start_factor = 'K', size_factor = 'K';
+			unsigned long start_base, size_base;
+
+			start_base = to_size_factor(range_startk, &start_factor);
+			size_base = to_size_factor(sizek, &size_factor);
+
+			Dprintk("Setting variable MTRR %d, "
+				"base: %ld%cB, range: %ld%cB, type %s\n",
+				reg, start_base, start_factor,
+				size_base, size_factor,
+				(type == MTRR_TYPE_UNCACHABLE) ? "UC" :
+				   ((type == MTRR_TYPE_WRBACK) ? "WB" : "Other")
+				);
+		}
+		save_var_mtrr(reg++, range_startk, sizek, type);
+		range_startk += sizek;
+		range_sizek -= sizek;
+		if (reg >= num_var_ranges)
+			break;
+	}
+	return reg;
+}
+
+static unsigned __init
+range_to_mtrr_with_hole(struct var_mtrr_state *state, unsigned long basek,
+			unsigned long sizek)
+{
+	unsigned long hole_basek, hole_sizek;
+	unsigned long second_sizek;
+	unsigned long range0_basek, range0_sizek;
+	unsigned long range_basek, range_sizek;
+	unsigned long chunk_sizek;
+	unsigned long gran_sizek;
+
+	hole_basek = 0;
+	hole_sizek = 0;
+	second_sizek = 0;
+	chunk_sizek = state->chunk_sizek;
+	gran_sizek = state->gran_sizek;
+
+	/* Align with gran size, prevent small block used up MTRRs: */
+	range_basek = ALIGN(state->range_startk, gran_sizek);
+	if ((range_basek > basek) && basek)
+		return second_sizek;
+
+	state->range_sizek -= (range_basek - state->range_startk);
+	range_sizek = ALIGN(state->range_sizek, gran_sizek);
+
+	while (range_sizek > state->range_sizek) {
+		range_sizek -= gran_sizek;
+		if (!range_sizek)
+			return 0;
+	}
+	state->range_sizek = range_sizek;
+
+	/* Try to append some small hole: */
+	range0_basek = state->range_startk;
+	range0_sizek = ALIGN(state->range_sizek, chunk_sizek);
+
+	/* No increase: */
+	if (range0_sizek == state->range_sizek) {
+		Dprintk("rangeX: %016lx - %016lx\n",
+			range0_basek<<10,
+			(range0_basek + state->range_sizek)<<10);
+		state->reg = range_to_mtrr(state->reg, range0_basek,
+				state->range_sizek, MTRR_TYPE_WRBACK);
+		return 0;
+	}
+
+	/* Only cut back when it is not the last: */
+	if (sizek) {
+		while (range0_basek + range0_sizek > (basek + sizek)) {
+			if (range0_sizek >= chunk_sizek)
+				range0_sizek -= chunk_sizek;
+			else
+				range0_sizek = 0;
+
+			if (!range0_sizek)
+				break;
+		}
+	}
+
+second_try:
+	range_basek = range0_basek + range0_sizek;
+
+	/* One hole in the middle: */
+	if (range_basek > basek && range_basek <= (basek + sizek))
+		second_sizek = range_basek - basek;
+
+	if (range0_sizek > state->range_sizek) {
+
+		/* One hole in middle or at the end: */
+		hole_sizek = range0_sizek - state->range_sizek - second_sizek;
+
+		/* Hole size should be less than half of range0 size: */
+		if (hole_sizek >= (range0_sizek >> 1) &&
+		    range0_sizek >= chunk_sizek) {
+			range0_sizek -= chunk_sizek;
+			second_sizek = 0;
+			hole_sizek = 0;
+
+			goto second_try;
+		}
+	}
+
+	if (range0_sizek) {
+		Dprintk("range0: %016lx - %016lx\n",
+			range0_basek<<10,
+			(range0_basek + range0_sizek)<<10);
+		state->reg = range_to_mtrr(state->reg, range0_basek,
+				range0_sizek, MTRR_TYPE_WRBACK);
+	}
+
+	if (range0_sizek < state->range_sizek) {
+		/* Need to handle left over range: */
+		range_sizek = state->range_sizek - range0_sizek;
+
+		Dprintk("range: %016lx - %016lx\n",
+			 range_basek<<10,
+			 (range_basek + range_sizek)<<10);
+
+		state->reg = range_to_mtrr(state->reg, range_basek,
+				 range_sizek, MTRR_TYPE_WRBACK);
+	}
+
+	if (hole_sizek) {
+		hole_basek = range_basek - hole_sizek - second_sizek;
+		Dprintk("hole: %016lx - %016lx\n",
+			 hole_basek<<10,
+			 (hole_basek + hole_sizek)<<10);
+		state->reg = range_to_mtrr(state->reg, hole_basek,
+				 hole_sizek, MTRR_TYPE_UNCACHABLE);
+	}
+
+	return second_sizek;
+}
+
+static void __init
+set_var_mtrr_range(struct var_mtrr_state *state, unsigned long base_pfn,
+		   unsigned long size_pfn)
+{
+	unsigned long basek, sizek;
+	unsigned long second_sizek = 0;
+
+	if (state->reg >= num_var_ranges)
+		return;
+
+	basek = base_pfn << (PAGE_SHIFT - 10);
+	sizek = size_pfn << (PAGE_SHIFT - 10);
+
+	/* See if I can merge with the last range: */
+	if ((basek <= 1024) ||
+	    (state->range_startk + state->range_sizek == basek)) {
+		unsigned long endk = basek + sizek;
+		state->range_sizek = endk - state->range_startk;
+		return;
+	}
+	/* Write the range mtrrs: */
+	if (state->range_sizek != 0)
+		second_sizek = range_to_mtrr_with_hole(state, basek, sizek);
+
+	/* Allocate an msr: */
+	state->range_startk = basek + second_sizek;
+	state->range_sizek  = sizek - second_sizek;
+}
+
+/* Minimum size of mtrr block that can take hole: */
+static u64 mtrr_chunk_size __initdata = (256ULL<<20);
+
+static int __init parse_mtrr_chunk_size_opt(char *p)
+{
+	if (!p)
+		return -EINVAL;
+	mtrr_chunk_size = memparse(p, &p);
+	return 0;
+}
+early_param("mtrr_chunk_size", parse_mtrr_chunk_size_opt);
+
+/* Granularity of mtrr of block: */
+static u64 mtrr_gran_size __initdata;
+
+static int __init parse_mtrr_gran_size_opt(char *p)
+{
+	if (!p)
+		return -EINVAL;
+	mtrr_gran_size = memparse(p, &p);
+	return 0;
+}
+early_param("mtrr_gran_size", parse_mtrr_gran_size_opt);
+
+static unsigned long nr_mtrr_spare_reg __initdata =
+				 CONFIG_MTRR_SANITIZER_SPARE_REG_NR_DEFAULT;
+
+static int __init parse_mtrr_spare_reg(char *arg)
+{
+	if (arg)
+		nr_mtrr_spare_reg = simple_strtoul(arg, NULL, 0);
+	return 0;
+}
+early_param("mtrr_spare_reg_nr", parse_mtrr_spare_reg);
+
+static int __init
+x86_setup_var_mtrrs(struct range *range, int nr_range,
+		    u64 chunk_size, u64 gran_size)
+{
+	struct var_mtrr_state var_state;
+	int num_reg;
+	int i;
+
+	var_state.range_startk	= 0;
+	var_state.range_sizek	= 0;
+	var_state.reg		= 0;
+	var_state.chunk_sizek	= chunk_size >> 10;
+	var_state.gran_sizek	= gran_size >> 10;
+
+	memset(range_state, 0, sizeof(range_state));
+
+	/* Write the range: */
+	for (i = 0; i < nr_range; i++) {
+		set_var_mtrr_range(&var_state, range[i].start,
+				   range[i].end - range[i].start);
+	}
+
+	/* Write the last range: */
+	if (var_state.range_sizek != 0)
+		range_to_mtrr_with_hole(&var_state, 0, 0);
+
+	num_reg = var_state.reg;
+	/* Clear out the extra MTRR's: */
+	while (var_state.reg < num_var_ranges) {
+		save_var_mtrr(var_state.reg, 0, 0, 0);
+		var_state.reg++;
+	}
+
+	return num_reg;
+}
+
+struct mtrr_cleanup_result {
+	unsigned long	gran_sizek;
+	unsigned long	chunk_sizek;
+	unsigned long	lose_cover_sizek;
+	unsigned int	num_reg;
+	int		bad;
+};
+
+/*
+ * gran_size: 64K, 128K, 256K, 512K, 1M, 2M, ..., 2G
+ * chunk size: gran_size, ..., 2G
+ * so we need (1+16)*8
+ */
+#define NUM_RESULT	136
+#define PSHIFT		(PAGE_SHIFT - 10)
+
+static struct mtrr_cleanup_result __initdata result[NUM_RESULT];
+static unsigned long __initdata min_loss_pfn[RANGE_NUM];
+
+static void __init print_out_mtrr_range_state(void)
+{
+	char start_factor = 'K', size_factor = 'K';
+	unsigned long start_base, size_base;
+	mtrr_type type;
+	int i;
+
+	for (i = 0; i < num_var_ranges; i++) {
+
+		size_base = range_state[i].size_pfn << (PAGE_SHIFT - 10);
+		if (!size_base)
+			continue;
+
+		size_base = to_size_factor(size_base, &size_factor);
+		start_base = range_state[i].base_pfn << (PAGE_SHIFT - 10);
+		start_base = to_size_factor(start_base, &start_factor);
+		type = range_state[i].type;
+
+		Dprintk("reg %d, base: %ld%cB, range: %ld%cB, type %s\n",
+			i, start_base, start_factor,
+			size_base, size_factor,
+			(type == MTRR_TYPE_UNCACHABLE) ? "UC" :
+			    ((type == MTRR_TYPE_WRPROT) ? "WP" :
+			     ((type == MTRR_TYPE_WRBACK) ? "WB" : "Other"))
+			);
+	}
+}
+
+static int __init mtrr_need_cleanup(void)
+{
+	int i;
+	mtrr_type type;
+	unsigned long size;
+	/* Extra one for all 0: */
+	int num[MTRR_NUM_TYPES + 1];
+
+	/* Check entries number: */
+	memset(num, 0, sizeof(num));
+	for (i = 0; i < num_var_ranges; i++) {
+		type = range_state[i].type;
+		size = range_state[i].size_pfn;
+		if (type >= MTRR_NUM_TYPES)
+			continue;
+		if (!size)
+			type = MTRR_NUM_TYPES;
+		num[type]++;
+	}
+
+	/* Check if we got UC entries: */
+	if (!num[MTRR_TYPE_UNCACHABLE])
+		return 0;
+
+	/* Check if we only had WB and UC */
+	if (num[MTRR_TYPE_WRBACK] + num[MTRR_TYPE_UNCACHABLE] !=
+	    num_var_ranges - num[MTRR_NUM_TYPES])
+		return 0;
+
+	return 1;
+}
+
+static unsigned long __initdata range_sums;
+
+static void __init
+mtrr_calc_range_state(u64 chunk_size, u64 gran_size,
+		      unsigned long x_remove_base,
+		      unsigned long x_remove_size, int i)
+{
+	/*
+	 * range_new should really be an automatic variable, but
+	 * putting 4096 bytes on the stack is frowned upon, to put it
+	 * mildly. It is safe to make it a static __initdata variable,
+	 * since mtrr_calc_range_state is only called during init and
+	 * there's no way it will call itself recursively.
+	 */
+	static struct range range_new[RANGE_NUM] __initdata;
+	unsigned long range_sums_new;
+	int nr_range_new;
+	int num_reg;
+
+	/* Convert ranges to var ranges state: */
+	num_reg = x86_setup_var_mtrrs(range, nr_range, chunk_size, gran_size);
+
+	/* We got new setting in range_state, check it: */
+	memset(range_new, 0, sizeof(range_new));
+	nr_range_new = x86_get_mtrr_mem_range(range_new, 0,
+				x_remove_base, x_remove_size);
+	range_sums_new = sum_ranges(range_new, nr_range_new);
+
+	result[i].chunk_sizek = chunk_size >> 10;
+	result[i].gran_sizek = gran_size >> 10;
+	result[i].num_reg = num_reg;
+
+	if (range_sums < range_sums_new) {
+		result[i].lose_cover_sizek = (range_sums_new - range_sums) << PSHIFT;
+		result[i].bad = 1;
+	} else {
+		result[i].lose_cover_sizek = (range_sums - range_sums_new) << PSHIFT;
+	}
+
+	/* Double check it: */
+	if (!result[i].bad && !result[i].lose_cover_sizek) {
+		if (nr_range_new != nr_range || memcmp(range, range_new, sizeof(range)))
+			result[i].bad = 1;
+	}
+
+	if (!result[i].bad && (range_sums - range_sums_new < min_loss_pfn[num_reg]))
+		min_loss_pfn[num_reg] = range_sums - range_sums_new;
+}
+
+static void __init mtrr_print_out_one_result(int i)
+{
+	unsigned long gran_base, chunk_base, lose_base;
+	char gran_factor, chunk_factor, lose_factor;
+
+	gran_base = to_size_factor(result[i].gran_sizek, &gran_factor);
+	chunk_base = to_size_factor(result[i].chunk_sizek, &chunk_factor);
+	lose_base = to_size_factor(result[i].lose_cover_sizek, &lose_factor);
+
+	pr_info("%sgran_size: %ld%c \tchunk_size: %ld%c \t",
+		result[i].bad ? "*BAD*" : " ",
+		gran_base, gran_factor, chunk_base, chunk_factor);
+	pr_cont("num_reg: %d  \tlose cover RAM: %s%ld%c\n",
+		result[i].num_reg, result[i].bad ? "-" : "",
+		lose_base, lose_factor);
+}
+
+static int __init mtrr_search_optimal_index(void)
+{
+	int num_reg_good;
+	int index_good;
+	int i;
+
+	if (nr_mtrr_spare_reg >= num_var_ranges)
+		nr_mtrr_spare_reg = num_var_ranges - 1;
+
+	num_reg_good = -1;
+	for (i = num_var_ranges - nr_mtrr_spare_reg; i > 0; i--) {
+		if (!min_loss_pfn[i])
+			num_reg_good = i;
+	}
+
+	index_good = -1;
+	if (num_reg_good != -1) {
+		for (i = 0; i < NUM_RESULT; i++) {
+			if (!result[i].bad &&
+			    result[i].num_reg == num_reg_good &&
+			    !result[i].lose_cover_sizek) {
+				index_good = i;
+				break;
+			}
+		}
+	}
+
+	return index_good;
+}
+
+int __init mtrr_cleanup(void)
+{
+	unsigned long x_remove_base, x_remove_size;
+	unsigned long base, size, def, dummy;
+	u64 chunk_size, gran_size;
+	mtrr_type type;
+	int index_good;
+	int i;
+
+	if (!mtrr_enabled())
+		return 0;
+
+	if (!cpu_feature_enabled(X86_FEATURE_MTRR) || enable_mtrr_cleanup < 1)
+		return 0;
+
+	rdmsr(MSR_MTRRdefType, def, dummy);
+	def &= 0xff;
+	if (def != MTRR_TYPE_UNCACHABLE)
+		return 0;
+
+	/* Get it and store it aside: */
+	memset(range_state, 0, sizeof(range_state));
+	for (i = 0; i < num_var_ranges; i++) {
+		mtrr_if->get(i, &base, &size, &type);
+		range_state[i].base_pfn = base;
+		range_state[i].size_pfn = size;
+		range_state[i].type = type;
+	}
+
+	/* Check if we need handle it and can handle it: */
+	if (!mtrr_need_cleanup())
+		return 0;
+
+	/* Print original var MTRRs at first, for debugging: */
+	Dprintk("original variable MTRRs\n");
+	print_out_mtrr_range_state();
+
+	memset(range, 0, sizeof(range));
+	x_remove_size = 0;
+	x_remove_base = 1 << (32 - PAGE_SHIFT);
+	if (mtrr_tom2)
+		x_remove_size = (mtrr_tom2 >> PAGE_SHIFT) - x_remove_base;
+
+	/*
+	 * [0, 1M) should always be covered by var mtrr with WB
+	 * and fixed mtrrs should take effect before var mtrr for it:
+	 */
+	nr_range = add_range_with_merge(range, RANGE_NUM, 0, 0,
+					1ULL<<(20 - PAGE_SHIFT));
+	/* add from var mtrr at last */
+	nr_range = x86_get_mtrr_mem_range(range, nr_range,
+					  x_remove_base, x_remove_size);
+
+	range_sums = sum_ranges(range, nr_range);
+	pr_info("total RAM covered: %ldM\n",
+	       range_sums >> (20 - PAGE_SHIFT));
+
+	if (mtrr_chunk_size && mtrr_gran_size) {
+		i = 0;
+		mtrr_calc_range_state(mtrr_chunk_size, mtrr_gran_size,
+				      x_remove_base, x_remove_size, i);
+
+		mtrr_print_out_one_result(i);
+
+		if (!result[i].bad) {
+			set_var_mtrr_all();
+			Dprintk("New variable MTRRs\n");
+			print_out_mtrr_range_state();
+			return 1;
+		}
+		pr_info("invalid mtrr_gran_size or mtrr_chunk_size, will find optimal one\n");
+	}
+
+	i = 0;
+	memset(min_loss_pfn, 0xff, sizeof(min_loss_pfn));
+	memset(result, 0, sizeof(result));
+	for (gran_size = (1ULL<<16); gran_size < (1ULL<<32); gran_size <<= 1) {
+
+		for (chunk_size = gran_size; chunk_size < (1ULL<<32);
+		     chunk_size <<= 1) {
+
+			if (i >= NUM_RESULT)
+				continue;
+
+			mtrr_calc_range_state(chunk_size, gran_size,
+				      x_remove_base, x_remove_size, i);
+			if (mtrr_debug) {
+				mtrr_print_out_one_result(i);
+				pr_info("\n");
+			}
+
+			i++;
+		}
+	}
+
+	/* Try to find the optimal index: */
+	index_good = mtrr_search_optimal_index();
+
+	if (index_good != -1) {
+		pr_info("Found optimal setting for mtrr clean up\n");
+		i = index_good;
+		mtrr_print_out_one_result(i);
+
+		/* Convert ranges to var ranges state: */
+		chunk_size = result[i].chunk_sizek;
+		chunk_size <<= 10;
+		gran_size = result[i].gran_sizek;
+		gran_size <<= 10;
+		x86_setup_var_mtrrs(range, nr_range, chunk_size, gran_size);
+		set_var_mtrr_all();
+		Dprintk("New variable MTRRs\n");
+		print_out_mtrr_range_state();
+		return 1;
+	} else {
+		/* print out all */
+		for (i = 0; i < NUM_RESULT; i++)
+			mtrr_print_out_one_result(i);
+	}
+
+	pr_info("mtrr_cleanup: can not find optimal value\n");
+	pr_info("please specify mtrr_gran_size/mtrr_chunk_size\n");
+
+	return 0;
+}
+#else
+int __init mtrr_cleanup(void)
+{
+	return 0;
+}
+#endif
+
+static int disable_mtrr_trim;
+
+static int __init disable_mtrr_trim_setup(char *str)
+{
+	disable_mtrr_trim = 1;
+	return 0;
+}
+early_param("disable_mtrr_trim", disable_mtrr_trim_setup);
+
+/*
+ * Newer AMD K8s and later CPUs have a special magic MSR way to force WB
+ * for memory >4GB. Check for that here.
+ * Note this won't check if the MTRRs < 4GB where the magic bit doesn't
+ * apply to are wrong, but so far we don't know of any such case in the wild.
+ */
+#define Tom2Enabled		(1U << 21)
+#define Tom2ForceMemTypeWB	(1U << 22)
+
+int __init amd_special_default_mtrr(void)
+{
+	u32 l, h;
+
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
+	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
+		return 0;
+	if (boot_cpu_data.x86 < 0xf)
+		return 0;
+	/* In case some hypervisor doesn't pass SYSCFG through: */
+	if (rdmsr_safe(MSR_AMD64_SYSCFG, &l, &h) < 0)
+		return 0;
+	/*
+	 * Memory between 4GB and top of mem is forced WB by this magic bit.
+	 * Reserved before K8RevF, but should be zero there.
+	 */
+	if ((l & (Tom2Enabled | Tom2ForceMemTypeWB)) ==
+		 (Tom2Enabled | Tom2ForceMemTypeWB))
+		return 1;
+	return 0;
+}
+
+static u64 __init
+real_trim_memory(unsigned long start_pfn, unsigned long limit_pfn)
+{
+	u64 trim_start, trim_size;
+
+	trim_start = start_pfn;
+	trim_start <<= PAGE_SHIFT;
+
+	trim_size = limit_pfn;
+	trim_size <<= PAGE_SHIFT;
+	trim_size -= trim_start;
+
+	return e820__range_update(trim_start, trim_size, E820_TYPE_RAM, E820_TYPE_RESERVED);
+}
+
+/**
+ * mtrr_trim_uncached_memory - trim RAM not covered by MTRRs
+ * @end_pfn: ending page frame number
+ *
+ * Some buggy BIOSes don't setup the MTRRs properly for systems with certain
+ * memory configurations.  This routine checks that the highest MTRR matches
+ * the end of memory, to make sure the MTRRs having a write back type cover
+ * all of the memory the kernel is intending to use.  If not, it'll trim any
+ * memory off the end by adjusting end_pfn, removing it from the kernel's
+ * allocation pools, warning the user with an obnoxious message.
+ */
+int __init mtrr_trim_uncached_memory(unsigned long end_pfn)
+{
+	unsigned long i, base, size, highest_pfn = 0, def, dummy;
+	mtrr_type type;
+	u64 total_trim_size;
+	/* extra one for all 0 */
+	int num[MTRR_NUM_TYPES + 1];
+
+	if (!mtrr_enabled())
+		return 0;
+
+	/*
+	 * Make sure we only trim uncachable memory on machines that
+	 * support the Intel MTRR architecture:
+	 */
+	if (!cpu_feature_enabled(X86_FEATURE_MTRR) || disable_mtrr_trim)
+		return 0;
+
+	rdmsr(MSR_MTRRdefType, def, dummy);
+	def &= MTRR_DEF_TYPE_TYPE;
+	if (def != MTRR_TYPE_UNCACHABLE)
+		return 0;
+
+	/* Get it and store it aside: */
+	memset(range_state, 0, sizeof(range_state));
+	for (i = 0; i < num_var_ranges; i++) {
+		mtrr_if->get(i, &base, &size, &type);
+		range_state[i].base_pfn = base;
+		range_state[i].size_pfn = size;
+		range_state[i].type = type;
+	}
+
+	/* Find highest cached pfn: */
+	for (i = 0; i < num_var_ranges; i++) {
+		type = range_state[i].type;
+		if (type != MTRR_TYPE_WRBACK)
+			continue;
+		base = range_state[i].base_pfn;
+		size = range_state[i].size_pfn;
+		if (highest_pfn < base + size)
+			highest_pfn = base + size;
+	}
+
+	/* kvm/qemu doesn't have mtrr set right, don't trim them all: */
+	if (!highest_pfn) {
+		pr_info("CPU MTRRs all blank - virtualized system.\n");
+		return 0;
+	}
+
+	/* Check entries number: */
+	memset(num, 0, sizeof(num));
+	for (i = 0; i < num_var_ranges; i++) {
+		type = range_state[i].type;
+		if (type >= MTRR_NUM_TYPES)
+			continue;
+		size = range_state[i].size_pfn;
+		if (!size)
+			type = MTRR_NUM_TYPES;
+		num[type]++;
+	}
+
+	/* No entry for WB? */
+	if (!num[MTRR_TYPE_WRBACK])
+		return 0;
+
+	/* Check if we only had WB and UC: */
+	if (num[MTRR_TYPE_WRBACK] + num[MTRR_TYPE_UNCACHABLE] !=
+		num_var_ranges - num[MTRR_NUM_TYPES])
+		return 0;
+
+	memset(range, 0, sizeof(range));
+	nr_range = 0;
+	if (mtrr_tom2) {
+		range[nr_range].start = (1ULL<<(32 - PAGE_SHIFT));
+		range[nr_range].end = mtrr_tom2 >> PAGE_SHIFT;
+		if (highest_pfn < range[nr_range].end)
+			highest_pfn = range[nr_range].end;
+		nr_range++;
+	}
+	nr_range = x86_get_mtrr_mem_range(range, nr_range, 0, 0);
+
+	/* Check the head: */
+	total_trim_size = 0;
+	if (range[0].start)
+		total_trim_size += real_trim_memory(0, range[0].start);
+
+	/* Check the holes: */
+	for (i = 0; i < nr_range - 1; i++) {
+		if (range[i].end < range[i+1].start)
+			total_trim_size += real_trim_memory(range[i].end,
+							    range[i+1].start);
+	}
+
+	/* Check the top: */
+	i = nr_range - 1;
+	if (range[i].end < end_pfn)
+		total_trim_size += real_trim_memory(range[i].end,
+							 end_pfn);
+
+	if (total_trim_size) {
+		pr_warn("WARNING: BIOS bug: CPU MTRRs don't cover all of memory, losing %lluMB of RAM.\n",
+			total_trim_size >> 20);
+
+		if (!changed_by_mtrr_cleanup)
+			WARN_ON(1);
+
+		pr_info("update e820 for mtrr\n");
+		e820__update_table_print();
+
+		return 1;
+	}
+
+	return 0;
+}
diff --git a/arch/x86/kernel/cpu/mtrr/cyrix.c b/arch/x86/kernel/cpu/mtrr/cyrix.c
new file mode 100644
index 0000000000..238dad57d4
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/cyrix.c
@@ -0,0 +1,244 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+
+#include <asm/processor-cyrix.h>
+#include <asm/processor-flags.h>
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+
+#include "mtrr.h"
+
+static void
+cyrix_get_arr(unsigned int reg, unsigned long *base,
+	      unsigned long *size, mtrr_type * type)
+{
+	unsigned char arr, ccr3, rcr, shift;
+	unsigned long flags;
+
+	arr = CX86_ARR_BASE + (reg << 1) + reg;	/* avoid multiplication by 3 */
+
+	local_irq_save(flags);
+
+	ccr3 = getCx86(CX86_CCR3);
+	setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10);	/* enable MAPEN */
+	((unsigned char *)base)[3] = getCx86(arr);
+	((unsigned char *)base)[2] = getCx86(arr + 1);
+	((unsigned char *)base)[1] = getCx86(arr + 2);
+	rcr = getCx86(CX86_RCR_BASE + reg);
+	setCx86(CX86_CCR3, ccr3);			/* disable MAPEN */
+
+	local_irq_restore(flags);
+
+	shift = ((unsigned char *) base)[1] & 0x0f;
+	*base >>= PAGE_SHIFT;
+
+	/*
+	 * Power of two, at least 4K on ARR0-ARR6, 256K on ARR7
+	 * Note: shift==0xf means 4G, this is unsupported.
+	 */
+	if (shift)
+		*size = (reg < 7 ? 0x1UL : 0x40UL) << (shift - 1);
+	else
+		*size = 0;
+
+	/* Bit 0 is Cache Enable on ARR7, Cache Disable on ARR0-ARR6 */
+	if (reg < 7) {
+		switch (rcr) {
+		case 1:
+			*type = MTRR_TYPE_UNCACHABLE;
+			break;
+		case 8:
+			*type = MTRR_TYPE_WRBACK;
+			break;
+		case 9:
+			*type = MTRR_TYPE_WRCOMB;
+			break;
+		case 24:
+		default:
+			*type = MTRR_TYPE_WRTHROUGH;
+			break;
+		}
+	} else {
+		switch (rcr) {
+		case 0:
+			*type = MTRR_TYPE_UNCACHABLE;
+			break;
+		case 8:
+			*type = MTRR_TYPE_WRCOMB;
+			break;
+		case 9:
+			*type = MTRR_TYPE_WRBACK;
+			break;
+		case 25:
+		default:
+			*type = MTRR_TYPE_WRTHROUGH;
+			break;
+		}
+	}
+}
+
+/*
+ * cyrix_get_free_region - get a free ARR.
+ *
+ * @base: the starting (base) address of the region.
+ * @size: the size (in bytes) of the region.
+ *
+ * Returns: the index of the region on success, else -1 on error.
+*/
+static int
+cyrix_get_free_region(unsigned long base, unsigned long size, int replace_reg)
+{
+	unsigned long lbase, lsize;
+	mtrr_type ltype;
+	int i;
+
+	switch (replace_reg) {
+	case 7:
+		if (size < 0x40)
+			break;
+		fallthrough;
+	case 6:
+	case 5:
+	case 4:
+		return replace_reg;
+	case 3:
+	case 2:
+	case 1:
+	case 0:
+		return replace_reg;
+	}
+	/* If we are to set up a region >32M then look at ARR7 immediately */
+	if (size > 0x2000) {
+		cyrix_get_arr(7, &lbase, &lsize, &ltype);
+		if (lsize == 0)
+			return 7;
+		/* Else try ARR0-ARR6 first  */
+	} else {
+		for (i = 0; i < 7; i++) {
+			cyrix_get_arr(i, &lbase, &lsize, &ltype);
+			if (lsize == 0)
+				return i;
+		}
+		/*
+		 * ARR0-ARR6 isn't free
+		 * try ARR7 but its size must be at least 256K
+		 */
+		cyrix_get_arr(i, &lbase, &lsize, &ltype);
+		if ((lsize == 0) && (size >= 0x40))
+			return i;
+	}
+	return -ENOSPC;
+}
+
+static u32 cr4, ccr3;
+
+static void prepare_set(void)
+{
+	u32 cr0;
+
+	/*  Save value of CR4 and clear Page Global Enable (bit 7)  */
+	if (boot_cpu_has(X86_FEATURE_PGE)) {
+		cr4 = __read_cr4();
+		__write_cr4(cr4 & ~X86_CR4_PGE);
+	}
+
+	/*
+	 * Disable and flush caches.
+	 * Note that wbinvd flushes the TLBs as a side-effect
+	 */
+	cr0 = read_cr0() | X86_CR0_CD;
+	wbinvd();
+	write_cr0(cr0);
+	wbinvd();
+
+	/* Cyrix ARRs - everything else was excluded at the top */
+	ccr3 = getCx86(CX86_CCR3);
+
+	/* Cyrix ARRs - everything else was excluded at the top */
+	setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10);
+}
+
+static void post_set(void)
+{
+	/* Flush caches and TLBs */
+	wbinvd();
+
+	/* Cyrix ARRs - everything else was excluded at the top */
+	setCx86(CX86_CCR3, ccr3);
+
+	/* Enable caches */
+	write_cr0(read_cr0() & ~X86_CR0_CD);
+
+	/* Restore value of CR4 */
+	if (boot_cpu_has(X86_FEATURE_PGE))
+		__write_cr4(cr4);
+}
+
+static void cyrix_set_arr(unsigned int reg, unsigned long base,
+			  unsigned long size, mtrr_type type)
+{
+	unsigned char arr, arr_type, arr_size;
+
+	arr = CX86_ARR_BASE + (reg << 1) + reg;	/* avoid multiplication by 3 */
+
+	/* count down from 32M (ARR0-ARR6) or from 2G (ARR7) */
+	if (reg >= 7)
+		size >>= 6;
+
+	size &= 0x7fff;		/* make sure arr_size <= 14 */
+	for (arr_size = 0; size; arr_size++, size >>= 1)
+		;
+
+	if (reg < 7) {
+		switch (type) {
+		case MTRR_TYPE_UNCACHABLE:
+			arr_type = 1;
+			break;
+		case MTRR_TYPE_WRCOMB:
+			arr_type = 9;
+			break;
+		case MTRR_TYPE_WRTHROUGH:
+			arr_type = 24;
+			break;
+		default:
+			arr_type = 8;
+			break;
+		}
+	} else {
+		switch (type) {
+		case MTRR_TYPE_UNCACHABLE:
+			arr_type = 0;
+			break;
+		case MTRR_TYPE_WRCOMB:
+			arr_type = 8;
+			break;
+		case MTRR_TYPE_WRTHROUGH:
+			arr_type = 25;
+			break;
+		default:
+			arr_type = 9;
+			break;
+		}
+	}
+
+	prepare_set();
+
+	base <<= PAGE_SHIFT;
+	setCx86(arr + 0,  ((unsigned char *)&base)[3]);
+	setCx86(arr + 1,  ((unsigned char *)&base)[2]);
+	setCx86(arr + 2, (((unsigned char *)&base)[1]) | arr_size);
+	setCx86(CX86_RCR_BASE + reg, arr_type);
+
+	post_set();
+}
+
+const struct mtrr_ops cyrix_mtrr_ops = {
+	.var_regs          = 8,
+	.set               = cyrix_set_arr,
+	.get               = cyrix_get_arr,
+	.get_free_region   = cyrix_get_free_region,
+	.validate_add_page = generic_validate_add_page,
+	.have_wrcomb       = positive_have_wrcomb,
+};
diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c
new file mode 100644
index 0000000000..2d6aa5d2e3
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/generic.c
@@ -0,0 +1,1070 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * This only handles 32bit MTRR on 32bit hosts. This is strictly wrong
+ * because MTRRs can span up to 40 bits (36bits on most modern x86)
+ */
+
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/cc_platform.h>
+#include <asm/processor-flags.h>
+#include <asm/cacheinfo.h>
+#include <asm/cpufeature.h>
+#include <asm/hypervisor.h>
+#include <asm/mshyperv.h>
+#include <asm/tlbflush.h>
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+#include <asm/memtype.h>
+
+#include "mtrr.h"
+
+struct fixed_range_block {
+	int base_msr;		/* start address of an MTRR block */
+	int ranges;		/* number of MTRRs in this block  */
+};
+
+static struct fixed_range_block fixed_range_blocks[] = {
+	{ MSR_MTRRfix64K_00000, 1 }, /* one   64k MTRR  */
+	{ MSR_MTRRfix16K_80000, 2 }, /* two   16k MTRRs */
+	{ MSR_MTRRfix4K_C0000,  8 }, /* eight  4k MTRRs */
+	{}
+};
+
+struct cache_map {
+	u64 start;
+	u64 end;
+	u64 flags;
+	u64 type:8;
+	u64 fixed:1;
+};
+
+bool mtrr_debug;
+
+static int __init mtrr_param_setup(char *str)
+{
+	int rc = 0;
+
+	if (!str)
+		return -EINVAL;
+	if (!strcmp(str, "debug"))
+		mtrr_debug = true;
+	else
+		rc = -EINVAL;
+
+	return rc;
+}
+early_param("mtrr", mtrr_param_setup);
+
+/*
+ * CACHE_MAP_MAX is the maximum number of memory ranges in cache_map, where
+ * no 2 adjacent ranges have the same cache mode (those would be merged).
+ * The number is based on the worst case:
+ * - no two adjacent fixed MTRRs share the same cache mode
+ * - one variable MTRR is spanning a huge area with mode WB
+ * - 255 variable MTRRs with mode UC all overlap with the WB MTRR, creating 2
+ *   additional ranges each (result like "ababababa...aba" with a = WB, b = UC),
+ *   accounting for MTRR_MAX_VAR_RANGES * 2 - 1 range entries
+ * - a TOP_MEM2 area (even with overlapping an UC MTRR can't add 2 range entries
+ *   to the possible maximum, as it always starts at 4GB, thus it can't be in
+ *   the middle of that MTRR, unless that MTRR starts at 0, which would remove
+ *   the initial "a" from the "abababa" pattern above)
+ * The map won't contain ranges with no matching MTRR (those fall back to the
+ * default cache mode).
+ */
+#define CACHE_MAP_MAX	(MTRR_NUM_FIXED_RANGES + MTRR_MAX_VAR_RANGES * 2)
+
+static struct cache_map init_cache_map[CACHE_MAP_MAX] __initdata;
+static struct cache_map *cache_map __refdata = init_cache_map;
+static unsigned int cache_map_size = CACHE_MAP_MAX;
+static unsigned int cache_map_n;
+static unsigned int cache_map_fixed;
+
+static unsigned long smp_changes_mask;
+static int mtrr_state_set;
+u64 mtrr_tom2;
+
+struct mtrr_state_type mtrr_state;
+EXPORT_SYMBOL_GPL(mtrr_state);
+
+/* Reserved bits in the high portion of the MTRRphysBaseN MSR. */
+u32 phys_hi_rsvd;
+
+/*
+ * BIOS is expected to clear MtrrFixDramModEn bit, see for example
+ * "BIOS and Kernel Developer's Guide for the AMD Athlon 64 and AMD
+ * Opteron Processors" (26094 Rev. 3.30 February 2006), section
+ * "13.2.1.2 SYSCFG Register": "The MtrrFixDramModEn bit should be set
+ * to 1 during BIOS initialization of the fixed MTRRs, then cleared to
+ * 0 for operation."
+ */
+static inline void k8_check_syscfg_dram_mod_en(void)
+{
+	u32 lo, hi;
+
+	if (!((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) &&
+	      (boot_cpu_data.x86 >= 0x0f)))
+		return;
+
+	rdmsr(MSR_AMD64_SYSCFG, lo, hi);
+	if (lo & K8_MTRRFIXRANGE_DRAM_MODIFY) {
+		pr_err(FW_WARN "MTRR: CPU %u: SYSCFG[MtrrFixDramModEn]"
+		       " not cleared by BIOS, clearing this bit\n",
+		       smp_processor_id());
+		lo &= ~K8_MTRRFIXRANGE_DRAM_MODIFY;
+		mtrr_wrmsr(MSR_AMD64_SYSCFG, lo, hi);
+	}
+}
+
+/* Get the size of contiguous MTRR range */
+static u64 get_mtrr_size(u64 mask)
+{
+	u64 size;
+
+	mask |= (u64)phys_hi_rsvd << 32;
+	size = -mask;
+
+	return size;
+}
+
+static u8 get_var_mtrr_state(unsigned int reg, u64 *start, u64 *size)
+{
+	struct mtrr_var_range *mtrr = mtrr_state.var_ranges + reg;
+
+	if (!(mtrr->mask_lo & MTRR_PHYSMASK_V))
+		return MTRR_TYPE_INVALID;
+
+	*start = (((u64)mtrr->base_hi) << 32) + (mtrr->base_lo & PAGE_MASK);
+	*size = get_mtrr_size((((u64)mtrr->mask_hi) << 32) +
+			      (mtrr->mask_lo & PAGE_MASK));
+
+	return mtrr->base_lo & MTRR_PHYSBASE_TYPE;
+}
+
+static u8 get_effective_type(u8 type1, u8 type2)
+{
+	if (type1 == MTRR_TYPE_UNCACHABLE || type2 == MTRR_TYPE_UNCACHABLE)
+		return MTRR_TYPE_UNCACHABLE;
+
+	if ((type1 == MTRR_TYPE_WRBACK && type2 == MTRR_TYPE_WRTHROUGH) ||
+	    (type1 == MTRR_TYPE_WRTHROUGH && type2 == MTRR_TYPE_WRBACK))
+		return MTRR_TYPE_WRTHROUGH;
+
+	if (type1 != type2)
+		return MTRR_TYPE_UNCACHABLE;
+
+	return type1;
+}
+
+static void rm_map_entry_at(int idx)
+{
+	cache_map_n--;
+	if (cache_map_n > idx) {
+		memmove(cache_map + idx, cache_map + idx + 1,
+			sizeof(*cache_map) * (cache_map_n - idx));
+	}
+}
+
+/*
+ * Add an entry into cache_map at a specific index.  Merges adjacent entries if
+ * appropriate.  Return the number of merges for correcting the scan index
+ * (this is needed as merging will reduce the number of entries, which will
+ * result in skipping entries in future iterations if the scan index isn't
+ * corrected).
+ * Note that the corrected index can never go below -1 (resulting in being 0 in
+ * the next scan iteration), as "2" is returned only if the current index is
+ * larger than zero.
+ */
+static int add_map_entry_at(u64 start, u64 end, u8 type, int idx)
+{
+	bool merge_prev = false, merge_next = false;
+
+	if (start >= end)
+		return 0;
+
+	if (idx > 0) {
+		struct cache_map *prev = cache_map + idx - 1;
+
+		if (!prev->fixed && start == prev->end && type == prev->type)
+			merge_prev = true;
+	}
+
+	if (idx < cache_map_n) {
+		struct cache_map *next = cache_map + idx;
+
+		if (!next->fixed && end == next->start && type == next->type)
+			merge_next = true;
+	}
+
+	if (merge_prev && merge_next) {
+		cache_map[idx - 1].end = cache_map[idx].end;
+		rm_map_entry_at(idx);
+		return 2;
+	}
+	if (merge_prev) {
+		cache_map[idx - 1].end = end;
+		return 1;
+	}
+	if (merge_next) {
+		cache_map[idx].start = start;
+		return 1;
+	}
+
+	/* Sanity check: the array should NEVER be too small! */
+	if (cache_map_n == cache_map_size) {
+		WARN(1, "MTRR cache mode memory map exhausted!\n");
+		cache_map_n = cache_map_fixed;
+		return 0;
+	}
+
+	if (cache_map_n > idx) {
+		memmove(cache_map + idx + 1, cache_map + idx,
+			sizeof(*cache_map) * (cache_map_n - idx));
+	}
+
+	cache_map[idx].start = start;
+	cache_map[idx].end = end;
+	cache_map[idx].type = type;
+	cache_map[idx].fixed = 0;
+	cache_map_n++;
+
+	return 0;
+}
+
+/* Clear a part of an entry. Return 1 if start of entry is still valid. */
+static int clr_map_range_at(u64 start, u64 end, int idx)
+{
+	int ret = start != cache_map[idx].start;
+	u64 tmp;
+
+	if (start == cache_map[idx].start && end == cache_map[idx].end) {
+		rm_map_entry_at(idx);
+	} else if (start == cache_map[idx].start) {
+		cache_map[idx].start = end;
+	} else if (end == cache_map[idx].end) {
+		cache_map[idx].end = start;
+	} else {
+		tmp = cache_map[idx].end;
+		cache_map[idx].end = start;
+		add_map_entry_at(end, tmp, cache_map[idx].type, idx + 1);
+	}
+
+	return ret;
+}
+
+/*
+ * Add MTRR to the map.  The current map is scanned and each part of the MTRR
+ * either overlapping with an existing entry or with a hole in the map is
+ * handled separately.
+ */
+static void add_map_entry(u64 start, u64 end, u8 type)
+{
+	u8 new_type, old_type;
+	u64 tmp;
+	int i;
+
+	for (i = 0; i < cache_map_n && start < end; i++) {
+		if (start >= cache_map[i].end)
+			continue;
+
+		if (start < cache_map[i].start) {
+			/* Region start has no overlap. */
+			tmp = min(end, cache_map[i].start);
+			i -= add_map_entry_at(start, tmp,  type, i);
+			start = tmp;
+			continue;
+		}
+
+		new_type = get_effective_type(type, cache_map[i].type);
+		old_type = cache_map[i].type;
+
+		if (cache_map[i].fixed || new_type == old_type) {
+			/* Cut off start of new entry. */
+			start = cache_map[i].end;
+			continue;
+		}
+
+		/* Handle only overlapping part of region. */
+		tmp = min(end, cache_map[i].end);
+		i += clr_map_range_at(start, tmp, i);
+		i -= add_map_entry_at(start, tmp, new_type, i);
+		start = tmp;
+	}
+
+	/* Add rest of region after last map entry (rest might be empty). */
+	add_map_entry_at(start, end, type, i);
+}
+
+/* Add variable MTRRs to cache map. */
+static void map_add_var(void)
+{
+	u64 start, size;
+	unsigned int i;
+	u8 type;
+
+	/*
+	 * Add AMD TOP_MEM2 area.  Can't be added in mtrr_build_map(), as it
+	 * needs to be added again when rebuilding the map due to potentially
+	 * having moved as a result of variable MTRRs for memory below 4GB.
+	 */
+	if (mtrr_tom2) {
+		add_map_entry(BIT_ULL(32), mtrr_tom2, MTRR_TYPE_WRBACK);
+		cache_map[cache_map_n - 1].fixed = 1;
+	}
+
+	for (i = 0; i < num_var_ranges; i++) {
+		type = get_var_mtrr_state(i, &start, &size);
+		if (type != MTRR_TYPE_INVALID)
+			add_map_entry(start, start + size, type);
+	}
+}
+
+/*
+ * Rebuild map by replacing variable entries.  Needs to be called when MTRR
+ * registers are being changed after boot, as such changes could include
+ * removals of registers, which are complicated to handle without rebuild of
+ * the map.
+ */
+void generic_rebuild_map(void)
+{
+	if (mtrr_if != &generic_mtrr_ops)
+		return;
+
+	cache_map_n = cache_map_fixed;
+
+	map_add_var();
+}
+
+static unsigned int __init get_cache_map_size(void)
+{
+	return cache_map_fixed + 2 * num_var_ranges + (mtrr_tom2 != 0);
+}
+
+/* Build the cache_map containing the cache modes per memory range. */
+void __init mtrr_build_map(void)
+{
+	u64 start, end, size;
+	unsigned int i;
+	u8 type;
+
+	/* Add fixed MTRRs, optimize for adjacent entries with same type. */
+	if (mtrr_state.enabled & MTRR_STATE_MTRR_FIXED_ENABLED) {
+		/*
+		 * Start with 64k size fixed entries, preset 1st one (hence the
+		 * loop below is starting with index 1).
+		 */
+		start = 0;
+		end = size = 0x10000;
+		type = mtrr_state.fixed_ranges[0];
+
+		for (i = 1; i < MTRR_NUM_FIXED_RANGES; i++) {
+			/* 8 64k entries, then 16 16k ones, rest 4k. */
+			if (i == 8 || i == 24)
+				size >>= 2;
+
+			if (mtrr_state.fixed_ranges[i] != type) {
+				add_map_entry(start, end, type);
+				start = end;
+				type = mtrr_state.fixed_ranges[i];
+			}
+			end += size;
+		}
+		add_map_entry(start, end, type);
+	}
+
+	/* Mark fixed, they take precedence. */
+	for (i = 0; i < cache_map_n; i++)
+		cache_map[i].fixed = 1;
+	cache_map_fixed = cache_map_n;
+
+	map_add_var();
+
+	pr_info("MTRR map: %u entries (%u fixed + %u variable; max %u), built from %u variable MTRRs\n",
+		cache_map_n, cache_map_fixed, cache_map_n - cache_map_fixed,
+		get_cache_map_size(), num_var_ranges + (mtrr_tom2 != 0));
+
+	if (mtrr_debug) {
+		for (i = 0; i < cache_map_n; i++) {
+			pr_info("%3u: %016llx-%016llx %s\n", i,
+				cache_map[i].start, cache_map[i].end - 1,
+				mtrr_attrib_to_str(cache_map[i].type));
+		}
+	}
+}
+
+/* Copy the cache_map from __initdata memory to dynamically allocated one. */
+void __init mtrr_copy_map(void)
+{
+	unsigned int new_size = get_cache_map_size();
+
+	if (!mtrr_state.enabled || !new_size) {
+		cache_map = NULL;
+		return;
+	}
+
+	mutex_lock(&mtrr_mutex);
+
+	cache_map = kcalloc(new_size, sizeof(*cache_map), GFP_KERNEL);
+	if (cache_map) {
+		memmove(cache_map, init_cache_map,
+			cache_map_n * sizeof(*cache_map));
+		cache_map_size = new_size;
+	} else {
+		mtrr_state.enabled = 0;
+		pr_err("MTRRs disabled due to allocation failure for lookup map.\n");
+	}
+
+	mutex_unlock(&mtrr_mutex);
+}
+
+/**
+ * mtrr_overwrite_state - set static MTRR state
+ *
+ * Used to set MTRR state via different means (e.g. with data obtained from
+ * a hypervisor).
+ * Is allowed only for special cases when running virtualized. Must be called
+ * from the x86_init.hyper.init_platform() hook.  It can be called only once.
+ * The MTRR state can't be changed afterwards.  To ensure that, X86_FEATURE_MTRR
+ * is cleared.
+ */
+void mtrr_overwrite_state(struct mtrr_var_range *var, unsigned int num_var,
+			  mtrr_type def_type)
+{
+	unsigned int i;
+
+	/* Only allowed to be called once before mtrr_bp_init(). */
+	if (WARN_ON_ONCE(mtrr_state_set))
+		return;
+
+	/* Only allowed when running virtualized. */
+	if (!cpu_feature_enabled(X86_FEATURE_HYPERVISOR))
+		return;
+
+	/*
+	 * Only allowed for special virtualization cases:
+	 * - when running as Hyper-V, SEV-SNP guest using vTOM
+	 * - when running as Xen PV guest
+	 * - when running as SEV-SNP or TDX guest to avoid unnecessary
+	 *   VMM communication/Virtualization exceptions (#VC, #VE)
+	 */
+	if (!cc_platform_has(CC_ATTR_GUEST_SEV_SNP) &&
+	    !hv_is_isolation_supported() &&
+	    !cpu_feature_enabled(X86_FEATURE_XENPV) &&
+	    !cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
+		return;
+
+	/* Disable MTRR in order to disable MTRR modifications. */
+	setup_clear_cpu_cap(X86_FEATURE_MTRR);
+
+	if (var) {
+		if (num_var > MTRR_MAX_VAR_RANGES) {
+			pr_warn("Trying to overwrite MTRR state with %u variable entries\n",
+				num_var);
+			num_var = MTRR_MAX_VAR_RANGES;
+		}
+		for (i = 0; i < num_var; i++)
+			mtrr_state.var_ranges[i] = var[i];
+		num_var_ranges = num_var;
+	}
+
+	mtrr_state.def_type = def_type;
+	mtrr_state.enabled |= MTRR_STATE_MTRR_ENABLED;
+
+	mtrr_state_set = 1;
+}
+
+static u8 type_merge(u8 type, u8 new_type, u8 *uniform)
+{
+	u8 effective_type;
+
+	if (type == MTRR_TYPE_INVALID)
+		return new_type;
+
+	effective_type = get_effective_type(type, new_type);
+	if (type != effective_type)
+		*uniform = 0;
+
+	return effective_type;
+}
+
+/**
+ * mtrr_type_lookup - look up memory type in MTRR
+ *
+ * Return Values:
+ * MTRR_TYPE_(type)  - The effective MTRR type for the region
+ * MTRR_TYPE_INVALID - MTRR is disabled
+ *
+ * Output Argument:
+ * uniform - Set to 1 when the returned MTRR type is valid for the whole
+ *	     region, set to 0 else.
+ */
+u8 mtrr_type_lookup(u64 start, u64 end, u8 *uniform)
+{
+	u8 type = MTRR_TYPE_INVALID;
+	unsigned int i;
+
+	if (!mtrr_state_set) {
+		/* Uniformity is unknown. */
+		*uniform = 0;
+		return MTRR_TYPE_UNCACHABLE;
+	}
+
+	*uniform = 1;
+
+	if (!(mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED))
+		return MTRR_TYPE_UNCACHABLE;
+
+	for (i = 0; i < cache_map_n && start < end; i++) {
+		/* Region after current map entry? -> continue with next one. */
+		if (start >= cache_map[i].end)
+			continue;
+
+		/* Start of region not covered by current map entry? */
+		if (start < cache_map[i].start) {
+			/* At least some part of region has default type. */
+			type = type_merge(type, mtrr_state.def_type, uniform);
+			/* End of region not covered, too? -> lookup done. */
+			if (end <= cache_map[i].start)
+				return type;
+		}
+
+		/* At least part of region covered by map entry. */
+		type = type_merge(type, cache_map[i].type, uniform);
+
+		start = cache_map[i].end;
+	}
+
+	/* End of region past last entry in map? -> use default type. */
+	if (start < end)
+		type = type_merge(type, mtrr_state.def_type, uniform);
+
+	return type;
+}
+
+/* Get the MSR pair relating to a var range */
+static void
+get_mtrr_var_range(unsigned int index, struct mtrr_var_range *vr)
+{
+	rdmsr(MTRRphysBase_MSR(index), vr->base_lo, vr->base_hi);
+	rdmsr(MTRRphysMask_MSR(index), vr->mask_lo, vr->mask_hi);
+}
+
+/* Fill the MSR pair relating to a var range */
+void fill_mtrr_var_range(unsigned int index,
+		u32 base_lo, u32 base_hi, u32 mask_lo, u32 mask_hi)
+{
+	struct mtrr_var_range *vr;
+
+	vr = mtrr_state.var_ranges;
+
+	vr[index].base_lo = base_lo;
+	vr[index].base_hi = base_hi;
+	vr[index].mask_lo = mask_lo;
+	vr[index].mask_hi = mask_hi;
+}
+
+static void get_fixed_ranges(mtrr_type *frs)
+{
+	unsigned int *p = (unsigned int *)frs;
+	int i;
+
+	k8_check_syscfg_dram_mod_en();
+
+	rdmsr(MSR_MTRRfix64K_00000, p[0], p[1]);
+
+	for (i = 0; i < 2; i++)
+		rdmsr(MSR_MTRRfix16K_80000 + i, p[2 + i * 2], p[3 + i * 2]);
+	for (i = 0; i < 8; i++)
+		rdmsr(MSR_MTRRfix4K_C0000 + i, p[6 + i * 2], p[7 + i * 2]);
+}
+
+void mtrr_save_fixed_ranges(void *info)
+{
+	if (boot_cpu_has(X86_FEATURE_MTRR))
+		get_fixed_ranges(mtrr_state.fixed_ranges);
+}
+
+static unsigned __initdata last_fixed_start;
+static unsigned __initdata last_fixed_end;
+static mtrr_type __initdata last_fixed_type;
+
+static void __init print_fixed_last(void)
+{
+	if (!last_fixed_end)
+		return;
+
+	pr_info("  %05X-%05X %s\n", last_fixed_start,
+		last_fixed_end - 1, mtrr_attrib_to_str(last_fixed_type));
+
+	last_fixed_end = 0;
+}
+
+static void __init update_fixed_last(unsigned base, unsigned end,
+				     mtrr_type type)
+{
+	last_fixed_start = base;
+	last_fixed_end = end;
+	last_fixed_type = type;
+}
+
+static void __init
+print_fixed(unsigned base, unsigned step, const mtrr_type *types)
+{
+	unsigned i;
+
+	for (i = 0; i < 8; ++i, ++types, base += step) {
+		if (last_fixed_end == 0) {
+			update_fixed_last(base, base + step, *types);
+			continue;
+		}
+		if (last_fixed_end == base && last_fixed_type == *types) {
+			last_fixed_end = base + step;
+			continue;
+		}
+		/* new segments: gap or different type */
+		print_fixed_last();
+		update_fixed_last(base, base + step, *types);
+	}
+}
+
+static void __init print_mtrr_state(void)
+{
+	unsigned int i;
+	int high_width;
+
+	pr_info("MTRR default type: %s\n",
+		mtrr_attrib_to_str(mtrr_state.def_type));
+	if (mtrr_state.have_fixed) {
+		pr_info("MTRR fixed ranges %sabled:\n",
+			((mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED) &&
+			 (mtrr_state.enabled & MTRR_STATE_MTRR_FIXED_ENABLED)) ?
+			 "en" : "dis");
+		print_fixed(0x00000, 0x10000, mtrr_state.fixed_ranges + 0);
+		for (i = 0; i < 2; ++i)
+			print_fixed(0x80000 + i * 0x20000, 0x04000,
+				    mtrr_state.fixed_ranges + (i + 1) * 8);
+		for (i = 0; i < 8; ++i)
+			print_fixed(0xC0000 + i * 0x08000, 0x01000,
+				    mtrr_state.fixed_ranges + (i + 3) * 8);
+
+		/* tail */
+		print_fixed_last();
+	}
+	pr_info("MTRR variable ranges %sabled:\n",
+		mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED ? "en" : "dis");
+	high_width = (boot_cpu_data.x86_phys_bits - (32 - PAGE_SHIFT) + 3) / 4;
+
+	for (i = 0; i < num_var_ranges; ++i) {
+		if (mtrr_state.var_ranges[i].mask_lo & MTRR_PHYSMASK_V)
+			pr_info("  %u base %0*X%05X000 mask %0*X%05X000 %s\n",
+				i,
+				high_width,
+				mtrr_state.var_ranges[i].base_hi,
+				mtrr_state.var_ranges[i].base_lo >> 12,
+				high_width,
+				mtrr_state.var_ranges[i].mask_hi,
+				mtrr_state.var_ranges[i].mask_lo >> 12,
+				mtrr_attrib_to_str(mtrr_state.var_ranges[i].base_lo &
+						    MTRR_PHYSBASE_TYPE));
+		else
+			pr_info("  %u disabled\n", i);
+	}
+	if (mtrr_tom2)
+		pr_info("TOM2: %016llx aka %lldM\n", mtrr_tom2, mtrr_tom2>>20);
+}
+
+/* Grab all of the MTRR state for this CPU into *state */
+bool __init get_mtrr_state(void)
+{
+	struct mtrr_var_range *vrs;
+	unsigned lo, dummy;
+	unsigned int i;
+
+	vrs = mtrr_state.var_ranges;
+
+	rdmsr(MSR_MTRRcap, lo, dummy);
+	mtrr_state.have_fixed = lo & MTRR_CAP_FIX;
+
+	for (i = 0; i < num_var_ranges; i++)
+		get_mtrr_var_range(i, &vrs[i]);
+	if (mtrr_state.have_fixed)
+		get_fixed_ranges(mtrr_state.fixed_ranges);
+
+	rdmsr(MSR_MTRRdefType, lo, dummy);
+	mtrr_state.def_type = lo & MTRR_DEF_TYPE_TYPE;
+	mtrr_state.enabled = (lo & MTRR_DEF_TYPE_ENABLE) >> MTRR_STATE_SHIFT;
+
+	if (amd_special_default_mtrr()) {
+		unsigned low, high;
+
+		/* TOP_MEM2 */
+		rdmsr(MSR_K8_TOP_MEM2, low, high);
+		mtrr_tom2 = high;
+		mtrr_tom2 <<= 32;
+		mtrr_tom2 |= low;
+		mtrr_tom2 &= 0xffffff800000ULL;
+	}
+
+	if (mtrr_debug)
+		print_mtrr_state();
+
+	mtrr_state_set = 1;
+
+	return !!(mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED);
+}
+
+/* Some BIOS's are messed up and don't set all MTRRs the same! */
+void __init mtrr_state_warn(void)
+{
+	unsigned long mask = smp_changes_mask;
+
+	if (!mask)
+		return;
+	if (mask & MTRR_CHANGE_MASK_FIXED)
+		pr_warn("mtrr: your CPUs had inconsistent fixed MTRR settings\n");
+	if (mask & MTRR_CHANGE_MASK_VARIABLE)
+		pr_warn("mtrr: your CPUs had inconsistent variable MTRR settings\n");
+	if (mask & MTRR_CHANGE_MASK_DEFTYPE)
+		pr_warn("mtrr: your CPUs had inconsistent MTRRdefType settings\n");
+
+	pr_info("mtrr: probably your BIOS does not setup all CPUs.\n");
+	pr_info("mtrr: corrected configuration.\n");
+}
+
+/*
+ * Doesn't attempt to pass an error out to MTRR users
+ * because it's quite complicated in some cases and probably not
+ * worth it because the best error handling is to ignore it.
+ */
+void mtrr_wrmsr(unsigned msr, unsigned a, unsigned b)
+{
+	if (wrmsr_safe(msr, a, b) < 0) {
+		pr_err("MTRR: CPU %u: Writing MSR %x to %x:%x failed\n",
+			smp_processor_id(), msr, a, b);
+	}
+}
+
+/**
+ * set_fixed_range - checks & updates a fixed-range MTRR if it
+ *		     differs from the value it should have
+ * @msr: MSR address of the MTTR which should be checked and updated
+ * @changed: pointer which indicates whether the MTRR needed to be changed
+ * @msrwords: pointer to the MSR values which the MSR should have
+ */
+static void set_fixed_range(int msr, bool *changed, unsigned int *msrwords)
+{
+	unsigned lo, hi;
+
+	rdmsr(msr, lo, hi);
+
+	if (lo != msrwords[0] || hi != msrwords[1]) {
+		mtrr_wrmsr(msr, msrwords[0], msrwords[1]);
+		*changed = true;
+	}
+}
+
+/**
+ * generic_get_free_region - Get a free MTRR.
+ * @base: The starting (base) address of the region.
+ * @size: The size (in bytes) of the region.
+ * @replace_reg: mtrr index to be replaced; set to invalid value if none.
+ *
+ * Returns: The index of the region on success, else negative on error.
+ */
+int
+generic_get_free_region(unsigned long base, unsigned long size, int replace_reg)
+{
+	unsigned long lbase, lsize;
+	mtrr_type ltype;
+	int i, max;
+
+	max = num_var_ranges;
+	if (replace_reg >= 0 && replace_reg < max)
+		return replace_reg;
+
+	for (i = 0; i < max; ++i) {
+		mtrr_if->get(i, &lbase, &lsize, &ltype);
+		if (lsize == 0)
+			return i;
+	}
+
+	return -ENOSPC;
+}
+
+static void generic_get_mtrr(unsigned int reg, unsigned long *base,
+			     unsigned long *size, mtrr_type *type)
+{
+	u32 mask_lo, mask_hi, base_lo, base_hi;
+	unsigned int hi;
+	u64 tmp, mask;
+
+	/*
+	 * get_mtrr doesn't need to update mtrr_state, also it could be called
+	 * from any cpu, so try to print it out directly.
+	 */
+	get_cpu();
+
+	rdmsr(MTRRphysMask_MSR(reg), mask_lo, mask_hi);
+
+	if (!(mask_lo & MTRR_PHYSMASK_V)) {
+		/*  Invalid (i.e. free) range */
+		*base = 0;
+		*size = 0;
+		*type = 0;
+		goto out_put_cpu;
+	}
+
+	rdmsr(MTRRphysBase_MSR(reg), base_lo, base_hi);
+
+	/* Work out the shifted address mask: */
+	tmp = (u64)mask_hi << 32 | (mask_lo & PAGE_MASK);
+	mask = (u64)phys_hi_rsvd << 32 | tmp;
+
+	/* Expand tmp with high bits to all 1s: */
+	hi = fls64(tmp);
+	if (hi > 0) {
+		tmp |= ~((1ULL<<(hi - 1)) - 1);
+
+		if (tmp != mask) {
+			pr_warn("mtrr: your BIOS has configured an incorrect mask, fixing it.\n");
+			add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
+			mask = tmp;
+		}
+	}
+
+	/*
+	 * This works correctly if size is a power of two, i.e. a
+	 * contiguous range:
+	 */
+	*size = -mask >> PAGE_SHIFT;
+	*base = (u64)base_hi << (32 - PAGE_SHIFT) | base_lo >> PAGE_SHIFT;
+	*type = base_lo & MTRR_PHYSBASE_TYPE;
+
+out_put_cpu:
+	put_cpu();
+}
+
+/**
+ * set_fixed_ranges - checks & updates the fixed-range MTRRs if they
+ *		      differ from the saved set
+ * @frs: pointer to fixed-range MTRR values, saved by get_fixed_ranges()
+ */
+static int set_fixed_ranges(mtrr_type *frs)
+{
+	unsigned long long *saved = (unsigned long long *)frs;
+	bool changed = false;
+	int block = -1, range;
+
+	k8_check_syscfg_dram_mod_en();
+
+	while (fixed_range_blocks[++block].ranges) {
+		for (range = 0; range < fixed_range_blocks[block].ranges; range++)
+			set_fixed_range(fixed_range_blocks[block].base_msr + range,
+					&changed, (unsigned int *)saved++);
+	}
+
+	return changed;
+}
+
+/*
+ * Set the MSR pair relating to a var range.
+ * Returns true if changes are made.
+ */
+static bool set_mtrr_var_ranges(unsigned int index, struct mtrr_var_range *vr)
+{
+	unsigned int lo, hi;
+	bool changed = false;
+
+	rdmsr(MTRRphysBase_MSR(index), lo, hi);
+	if ((vr->base_lo & ~MTRR_PHYSBASE_RSVD) != (lo & ~MTRR_PHYSBASE_RSVD)
+	    || (vr->base_hi & ~phys_hi_rsvd) != (hi & ~phys_hi_rsvd)) {
+
+		mtrr_wrmsr(MTRRphysBase_MSR(index), vr->base_lo, vr->base_hi);
+		changed = true;
+	}
+
+	rdmsr(MTRRphysMask_MSR(index), lo, hi);
+
+	if ((vr->mask_lo & ~MTRR_PHYSMASK_RSVD) != (lo & ~MTRR_PHYSMASK_RSVD)
+	    || (vr->mask_hi & ~phys_hi_rsvd) != (hi & ~phys_hi_rsvd)) {
+		mtrr_wrmsr(MTRRphysMask_MSR(index), vr->mask_lo, vr->mask_hi);
+		changed = true;
+	}
+	return changed;
+}
+
+static u32 deftype_lo, deftype_hi;
+
+/**
+ * set_mtrr_state - Set the MTRR state for this CPU.
+ *
+ * NOTE: The CPU must already be in a safe state for MTRR changes, including
+ *       measures that only a single CPU can be active in set_mtrr_state() in
+ *       order to not be subject to races for usage of deftype_lo. This is
+ *       accomplished by taking cache_disable_lock.
+ * RETURNS: 0 if no changes made, else a mask indicating what was changed.
+ */
+static unsigned long set_mtrr_state(void)
+{
+	unsigned long change_mask = 0;
+	unsigned int i;
+
+	for (i = 0; i < num_var_ranges; i++) {
+		if (set_mtrr_var_ranges(i, &mtrr_state.var_ranges[i]))
+			change_mask |= MTRR_CHANGE_MASK_VARIABLE;
+	}
+
+	if (mtrr_state.have_fixed && set_fixed_ranges(mtrr_state.fixed_ranges))
+		change_mask |= MTRR_CHANGE_MASK_FIXED;
+
+	/*
+	 * Set_mtrr_restore restores the old value of MTRRdefType,
+	 * so to set it we fiddle with the saved value:
+	 */
+	if ((deftype_lo & MTRR_DEF_TYPE_TYPE) != mtrr_state.def_type ||
+	    ((deftype_lo & MTRR_DEF_TYPE_ENABLE) >> MTRR_STATE_SHIFT) != mtrr_state.enabled) {
+
+		deftype_lo = (deftype_lo & MTRR_DEF_TYPE_DISABLE) |
+			     mtrr_state.def_type |
+			     (mtrr_state.enabled << MTRR_STATE_SHIFT);
+		change_mask |= MTRR_CHANGE_MASK_DEFTYPE;
+	}
+
+	return change_mask;
+}
+
+void mtrr_disable(void)
+{
+	/* Save MTRR state */
+	rdmsr(MSR_MTRRdefType, deftype_lo, deftype_hi);
+
+	/* Disable MTRRs, and set the default type to uncached */
+	mtrr_wrmsr(MSR_MTRRdefType, deftype_lo & MTRR_DEF_TYPE_DISABLE, deftype_hi);
+}
+
+void mtrr_enable(void)
+{
+	/* Intel (P6) standard MTRRs */
+	mtrr_wrmsr(MSR_MTRRdefType, deftype_lo, deftype_hi);
+}
+
+void mtrr_generic_set_state(void)
+{
+	unsigned long mask, count;
+
+	/* Actually set the state */
+	mask = set_mtrr_state();
+
+	/* Use the atomic bitops to update the global mask */
+	for (count = 0; count < sizeof(mask) * 8; ++count) {
+		if (mask & 0x01)
+			set_bit(count, &smp_changes_mask);
+		mask >>= 1;
+	}
+}
+
+/**
+ * generic_set_mtrr - set variable MTRR register on the local CPU.
+ *
+ * @reg: The register to set.
+ * @base: The base address of the region.
+ * @size: The size of the region. If this is 0 the region is disabled.
+ * @type: The type of the region.
+ *
+ * Returns nothing.
+ */
+static void generic_set_mtrr(unsigned int reg, unsigned long base,
+			     unsigned long size, mtrr_type type)
+{
+	unsigned long flags;
+	struct mtrr_var_range *vr;
+
+	vr = &mtrr_state.var_ranges[reg];
+
+	local_irq_save(flags);
+	cache_disable();
+
+	if (size == 0) {
+		/*
+		 * The invalid bit is kept in the mask, so we simply
+		 * clear the relevant mask register to disable a range.
+		 */
+		mtrr_wrmsr(MTRRphysMask_MSR(reg), 0, 0);
+		memset(vr, 0, sizeof(struct mtrr_var_range));
+	} else {
+		vr->base_lo = base << PAGE_SHIFT | type;
+		vr->base_hi = (base >> (32 - PAGE_SHIFT)) & ~phys_hi_rsvd;
+		vr->mask_lo = -size << PAGE_SHIFT | MTRR_PHYSMASK_V;
+		vr->mask_hi = (-size >> (32 - PAGE_SHIFT)) & ~phys_hi_rsvd;
+
+		mtrr_wrmsr(MTRRphysBase_MSR(reg), vr->base_lo, vr->base_hi);
+		mtrr_wrmsr(MTRRphysMask_MSR(reg), vr->mask_lo, vr->mask_hi);
+	}
+
+	cache_enable();
+	local_irq_restore(flags);
+}
+
+int generic_validate_add_page(unsigned long base, unsigned long size,
+			      unsigned int type)
+{
+	unsigned long lbase, last;
+
+	/*
+	 * For Intel PPro stepping <= 7
+	 * must be 4 MiB aligned and not touch 0x70000000 -> 0x7003FFFF
+	 */
+	if (mtrr_if == &generic_mtrr_ops && boot_cpu_data.x86 == 6 &&
+	    boot_cpu_data.x86_model == 1 &&
+	    boot_cpu_data.x86_stepping <= 7) {
+		if (base & ((1 << (22 - PAGE_SHIFT)) - 1)) {
+			pr_warn("mtrr: base(0x%lx000) is not 4 MiB aligned\n", base);
+			return -EINVAL;
+		}
+		if (!(base + size < 0x70000 || base > 0x7003F) &&
+		    (type == MTRR_TYPE_WRCOMB
+		     || type == MTRR_TYPE_WRBACK)) {
+			pr_warn("mtrr: writable mtrr between 0x70000000 and 0x7003FFFF may hang the CPU.\n");
+			return -EINVAL;
+		}
+	}
+
+	/*
+	 * Check upper bits of base and last are equal and lower bits are 0
+	 * for base and 1 for last
+	 */
+	last = base + size - 1;
+	for (lbase = base; !(lbase & 1) && (last & 1);
+	     lbase = lbase >> 1, last = last >> 1)
+		;
+	if (lbase != last) {
+		pr_warn("mtrr: base(0x%lx000) is not aligned on a size(0x%lx000) boundary\n", base, size);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int generic_have_wrcomb(void)
+{
+	unsigned long config, dummy;
+	rdmsr(MSR_MTRRcap, config, dummy);
+	return config & MTRR_CAP_WC;
+}
+
+int positive_have_wrcomb(void)
+{
+	return 1;
+}
+
+/*
+ * Generic structure...
+ */
+const struct mtrr_ops generic_mtrr_ops = {
+	.get			= generic_get_mtrr,
+	.get_free_region	= generic_get_free_region,
+	.set			= generic_set_mtrr,
+	.validate_add_page	= generic_validate_add_page,
+	.have_wrcomb		= generic_have_wrcomb,
+};
diff --git a/arch/x86/kernel/cpu/mtrr/if.c b/arch/x86/kernel/cpu/mtrr/if.c
new file mode 100644
index 0000000000..a5c506f6da
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/if.c
@@ -0,0 +1,425 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/capability.h>
+#include <linux/seq_file.h>
+#include <linux/uaccess.h>
+#include <linux/proc_fs.h>
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+
+#define LINE_SIZE 80
+
+#include <asm/mtrr.h>
+
+#include "mtrr.h"
+
+#define FILE_FCOUNT(f) (((struct seq_file *)((f)->private_data))->private)
+
+static const char *const mtrr_strings[MTRR_NUM_TYPES] =
+{
+	"uncachable",		/* 0 */
+	"write-combining",	/* 1 */
+	"?",			/* 2 */
+	"?",			/* 3 */
+	"write-through",	/* 4 */
+	"write-protect",	/* 5 */
+	"write-back",		/* 6 */
+};
+
+const char *mtrr_attrib_to_str(int x)
+{
+	return (x <= 6) ? mtrr_strings[x] : "?";
+}
+
+#ifdef CONFIG_PROC_FS
+
+static int
+mtrr_file_add(unsigned long base, unsigned long size,
+	      unsigned int type, bool increment, struct file *file, int page)
+{
+	unsigned int *fcount = FILE_FCOUNT(file);
+	int reg, max;
+
+	max = num_var_ranges;
+	if (fcount == NULL) {
+		fcount = kcalloc(max, sizeof(*fcount), GFP_KERNEL);
+		if (!fcount)
+			return -ENOMEM;
+		FILE_FCOUNT(file) = fcount;
+	}
+	if (!page) {
+		if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1)))
+			return -EINVAL;
+		base >>= PAGE_SHIFT;
+		size >>= PAGE_SHIFT;
+	}
+	reg = mtrr_add_page(base, size, type, true);
+	if (reg >= 0)
+		++fcount[reg];
+	return reg;
+}
+
+static int
+mtrr_file_del(unsigned long base, unsigned long size,
+	      struct file *file, int page)
+{
+	unsigned int *fcount = FILE_FCOUNT(file);
+	int reg;
+
+	if (!page) {
+		if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1)))
+			return -EINVAL;
+		base >>= PAGE_SHIFT;
+		size >>= PAGE_SHIFT;
+	}
+	reg = mtrr_del_page(-1, base, size);
+	if (reg < 0)
+		return reg;
+	if (fcount == NULL)
+		return reg;
+	if (fcount[reg] < 1)
+		return -EINVAL;
+	--fcount[reg];
+	return reg;
+}
+
+/*
+ * seq_file can seek but we ignore it.
+ *
+ * Format of control line:
+ *    "base=%Lx size=%Lx type=%s" or "disable=%d"
+ */
+static ssize_t
+mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos)
+{
+	int i, err;
+	unsigned long reg;
+	unsigned long long base, size;
+	char *ptr;
+	char line[LINE_SIZE];
+	int length;
+	size_t linelen;
+
+	memset(line, 0, LINE_SIZE);
+
+	len = min_t(size_t, len, LINE_SIZE - 1);
+	length = strncpy_from_user(line, buf, len);
+	if (length < 0)
+		return length;
+
+	linelen = strlen(line);
+	ptr = line + linelen - 1;
+	if (linelen && *ptr == '\n')
+		*ptr = '\0';
+
+	if (!strncmp(line, "disable=", 8)) {
+		reg = simple_strtoul(line + 8, &ptr, 0);
+		err = mtrr_del_page(reg, 0, 0);
+		if (err < 0)
+			return err;
+		return len;
+	}
+
+	if (strncmp(line, "base=", 5))
+		return -EINVAL;
+
+	base = simple_strtoull(line + 5, &ptr, 0);
+	ptr = skip_spaces(ptr);
+
+	if (strncmp(ptr, "size=", 5))
+		return -EINVAL;
+
+	size = simple_strtoull(ptr + 5, &ptr, 0);
+	if ((base & 0xfff) || (size & 0xfff))
+		return -EINVAL;
+	ptr = skip_spaces(ptr);
+
+	if (strncmp(ptr, "type=", 5))
+		return -EINVAL;
+	ptr = skip_spaces(ptr + 5);
+
+	i = match_string(mtrr_strings, MTRR_NUM_TYPES, ptr);
+	if (i < 0)
+		return i;
+
+	base >>= PAGE_SHIFT;
+	size >>= PAGE_SHIFT;
+	err = mtrr_add_page((unsigned long)base, (unsigned long)size, i, true);
+	if (err < 0)
+		return err;
+	return len;
+}
+
+static long
+mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
+{
+	int err = 0;
+	mtrr_type type;
+	unsigned long base;
+	unsigned long size;
+	struct mtrr_sentry sentry;
+	struct mtrr_gentry gentry;
+	void __user *arg = (void __user *) __arg;
+
+	memset(&gentry, 0, sizeof(gentry));
+
+	switch (cmd) {
+	case MTRRIOC_ADD_ENTRY:
+	case MTRRIOC_SET_ENTRY:
+	case MTRRIOC_DEL_ENTRY:
+	case MTRRIOC_KILL_ENTRY:
+	case MTRRIOC_ADD_PAGE_ENTRY:
+	case MTRRIOC_SET_PAGE_ENTRY:
+	case MTRRIOC_DEL_PAGE_ENTRY:
+	case MTRRIOC_KILL_PAGE_ENTRY:
+		if (copy_from_user(&sentry, arg, sizeof(sentry)))
+			return -EFAULT;
+		break;
+	case MTRRIOC_GET_ENTRY:
+	case MTRRIOC_GET_PAGE_ENTRY:
+		if (copy_from_user(&gentry, arg, sizeof(gentry)))
+			return -EFAULT;
+		break;
+#ifdef CONFIG_COMPAT
+	case MTRRIOC32_ADD_ENTRY:
+	case MTRRIOC32_SET_ENTRY:
+	case MTRRIOC32_DEL_ENTRY:
+	case MTRRIOC32_KILL_ENTRY:
+	case MTRRIOC32_ADD_PAGE_ENTRY:
+	case MTRRIOC32_SET_PAGE_ENTRY:
+	case MTRRIOC32_DEL_PAGE_ENTRY:
+	case MTRRIOC32_KILL_PAGE_ENTRY: {
+		struct mtrr_sentry32 __user *s32;
+
+		s32 = (struct mtrr_sentry32 __user *)__arg;
+		err = get_user(sentry.base, &s32->base);
+		err |= get_user(sentry.size, &s32->size);
+		err |= get_user(sentry.type, &s32->type);
+		if (err)
+			return err;
+		break;
+	}
+	case MTRRIOC32_GET_ENTRY:
+	case MTRRIOC32_GET_PAGE_ENTRY: {
+		struct mtrr_gentry32 __user *g32;
+
+		g32 = (struct mtrr_gentry32 __user *)__arg;
+		err = get_user(gentry.regnum, &g32->regnum);
+		err |= get_user(gentry.base, &g32->base);
+		err |= get_user(gentry.size, &g32->size);
+		err |= get_user(gentry.type, &g32->type);
+		if (err)
+			return err;
+		break;
+	}
+#endif
+	}
+
+	switch (cmd) {
+	default:
+		return -ENOTTY;
+	case MTRRIOC_ADD_ENTRY:
+#ifdef CONFIG_COMPAT
+	case MTRRIOC32_ADD_ENTRY:
+#endif
+		err =
+		    mtrr_file_add(sentry.base, sentry.size, sentry.type, true,
+				  file, 0);
+		break;
+	case MTRRIOC_SET_ENTRY:
+#ifdef CONFIG_COMPAT
+	case MTRRIOC32_SET_ENTRY:
+#endif
+		err = mtrr_add(sentry.base, sentry.size, sentry.type, false);
+		break;
+	case MTRRIOC_DEL_ENTRY:
+#ifdef CONFIG_COMPAT
+	case MTRRIOC32_DEL_ENTRY:
+#endif
+		err = mtrr_file_del(sentry.base, sentry.size, file, 0);
+		break;
+	case MTRRIOC_KILL_ENTRY:
+#ifdef CONFIG_COMPAT
+	case MTRRIOC32_KILL_ENTRY:
+#endif
+		err = mtrr_del(-1, sentry.base, sentry.size);
+		break;
+	case MTRRIOC_GET_ENTRY:
+#ifdef CONFIG_COMPAT
+	case MTRRIOC32_GET_ENTRY:
+#endif
+		if (gentry.regnum >= num_var_ranges)
+			return -EINVAL;
+		mtrr_if->get(gentry.regnum, &base, &size, &type);
+
+		/* Hide entries that go above 4GB */
+		if (base + size - 1 >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT))
+		    || size >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT)))
+			gentry.base = gentry.size = gentry.type = 0;
+		else {
+			gentry.base = base << PAGE_SHIFT;
+			gentry.size = size << PAGE_SHIFT;
+			gentry.type = type;
+		}
+
+		break;
+	case MTRRIOC_ADD_PAGE_ENTRY:
+#ifdef CONFIG_COMPAT
+	case MTRRIOC32_ADD_PAGE_ENTRY:
+#endif
+		err =
+		    mtrr_file_add(sentry.base, sentry.size, sentry.type, true,
+				  file, 1);
+		break;
+	case MTRRIOC_SET_PAGE_ENTRY:
+#ifdef CONFIG_COMPAT
+	case MTRRIOC32_SET_PAGE_ENTRY:
+#endif
+		err =
+		    mtrr_add_page(sentry.base, sentry.size, sentry.type, false);
+		break;
+	case MTRRIOC_DEL_PAGE_ENTRY:
+#ifdef CONFIG_COMPAT
+	case MTRRIOC32_DEL_PAGE_ENTRY:
+#endif
+		err = mtrr_file_del(sentry.base, sentry.size, file, 1);
+		break;
+	case MTRRIOC_KILL_PAGE_ENTRY:
+#ifdef CONFIG_COMPAT
+	case MTRRIOC32_KILL_PAGE_ENTRY:
+#endif
+		err = mtrr_del_page(-1, sentry.base, sentry.size);
+		break;
+	case MTRRIOC_GET_PAGE_ENTRY:
+#ifdef CONFIG_COMPAT
+	case MTRRIOC32_GET_PAGE_ENTRY:
+#endif
+		if (gentry.regnum >= num_var_ranges)
+			return -EINVAL;
+		mtrr_if->get(gentry.regnum, &base, &size, &type);
+		/* Hide entries that would overflow */
+		if (size != (__typeof__(gentry.size))size)
+			gentry.base = gentry.size = gentry.type = 0;
+		else {
+			gentry.base = base;
+			gentry.size = size;
+			gentry.type = type;
+		}
+		break;
+	}
+
+	if (err)
+		return err;
+
+	switch (cmd) {
+	case MTRRIOC_GET_ENTRY:
+	case MTRRIOC_GET_PAGE_ENTRY:
+		if (copy_to_user(arg, &gentry, sizeof(gentry)))
+			err = -EFAULT;
+		break;
+#ifdef CONFIG_COMPAT
+	case MTRRIOC32_GET_ENTRY:
+	case MTRRIOC32_GET_PAGE_ENTRY: {
+		struct mtrr_gentry32 __user *g32;
+
+		g32 = (struct mtrr_gentry32 __user *)__arg;
+		err = put_user(gentry.base, &g32->base);
+		err |= put_user(gentry.size, &g32->size);
+		err |= put_user(gentry.regnum, &g32->regnum);
+		err |= put_user(gentry.type, &g32->type);
+		break;
+	}
+#endif
+	}
+	return err;
+}
+
+static int mtrr_close(struct inode *ino, struct file *file)
+{
+	unsigned int *fcount = FILE_FCOUNT(file);
+	int i, max;
+
+	if (fcount != NULL) {
+		max = num_var_ranges;
+		for (i = 0; i < max; ++i) {
+			while (fcount[i] > 0) {
+				mtrr_del(i, 0, 0);
+				--fcount[i];
+			}
+		}
+		kfree(fcount);
+		FILE_FCOUNT(file) = NULL;
+	}
+	return single_release(ino, file);
+}
+
+static int mtrr_seq_show(struct seq_file *seq, void *offset)
+{
+	char factor;
+	int i, max;
+	mtrr_type type;
+	unsigned long base, size;
+
+	max = num_var_ranges;
+	for (i = 0; i < max; i++) {
+		mtrr_if->get(i, &base, &size, &type);
+		if (size == 0) {
+			mtrr_usage_table[i] = 0;
+			continue;
+		}
+		if (size < (0x100000 >> PAGE_SHIFT)) {
+			/* less than 1MB */
+			factor = 'K';
+			size <<= PAGE_SHIFT - 10;
+		} else {
+			factor = 'M';
+			size >>= 20 - PAGE_SHIFT;
+		}
+		/* Base can be > 32bit */
+		seq_printf(seq, "reg%02i: base=0x%06lx000 (%5luMB), size=%5lu%cB, count=%d: %s\n",
+			   i, base, base >> (20 - PAGE_SHIFT),
+			   size, factor,
+			   mtrr_usage_table[i], mtrr_attrib_to_str(type));
+	}
+	return 0;
+}
+
+static int mtrr_open(struct inode *inode, struct file *file)
+{
+	if (!mtrr_if)
+		return -EIO;
+	if (!mtrr_if->get)
+		return -ENXIO;
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+	return single_open(file, mtrr_seq_show, NULL);
+}
+
+static const struct proc_ops mtrr_proc_ops = {
+	.proc_open		= mtrr_open,
+	.proc_read		= seq_read,
+	.proc_lseek		= seq_lseek,
+	.proc_write		= mtrr_write,
+	.proc_ioctl		= mtrr_ioctl,
+#ifdef CONFIG_COMPAT
+	.proc_compat_ioctl	= mtrr_ioctl,
+#endif
+	.proc_release		= mtrr_close,
+};
+
+static int __init mtrr_if_init(void)
+{
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+
+	if ((!cpu_has(c, X86_FEATURE_MTRR)) &&
+	    (!cpu_has(c, X86_FEATURE_K6_MTRR)) &&
+	    (!cpu_has(c, X86_FEATURE_CYRIX_ARR)) &&
+	    (!cpu_has(c, X86_FEATURE_CENTAUR_MCR)))
+		return -ENODEV;
+
+	proc_create("mtrr", S_IWUSR | S_IRUGO, NULL, &mtrr_proc_ops);
+	return 0;
+}
+arch_initcall(mtrr_if_init);
+#endif			/*  CONFIG_PROC_FS  */
diff --git a/arch/x86/kernel/cpu/mtrr/legacy.c b/arch/x86/kernel/cpu/mtrr/legacy.c
new file mode 100644
index 0000000000..d25882fcf1
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/legacy.c
@@ -0,0 +1,90 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/syscore_ops.h>
+#include <asm/cpufeature.h>
+#include <asm/mtrr.h>
+#include <asm/processor.h>
+#include "mtrr.h"
+
+void mtrr_set_if(void)
+{
+	switch (boot_cpu_data.x86_vendor) {
+	case X86_VENDOR_AMD:
+		/* Pre-Athlon (K6) AMD CPU MTRRs */
+		if (cpu_feature_enabled(X86_FEATURE_K6_MTRR))
+			mtrr_if = &amd_mtrr_ops;
+		break;
+	case X86_VENDOR_CENTAUR:
+		if (cpu_feature_enabled(X86_FEATURE_CENTAUR_MCR))
+			mtrr_if = &centaur_mtrr_ops;
+		break;
+	case X86_VENDOR_CYRIX:
+		if (cpu_feature_enabled(X86_FEATURE_CYRIX_ARR))
+			mtrr_if = &cyrix_mtrr_ops;
+		break;
+	default:
+		break;
+	}
+}
+
+/*
+ * The suspend/resume methods are only for CPUs without MTRR. CPUs using generic
+ * MTRR driver don't require this.
+ */
+struct mtrr_value {
+	mtrr_type	ltype;
+	unsigned long	lbase;
+	unsigned long	lsize;
+};
+
+static struct mtrr_value *mtrr_value;
+
+static int mtrr_save(void)
+{
+	int i;
+
+	if (!mtrr_value)
+		return -ENOMEM;
+
+	for (i = 0; i < num_var_ranges; i++) {
+		mtrr_if->get(i, &mtrr_value[i].lbase,
+				&mtrr_value[i].lsize,
+				&mtrr_value[i].ltype);
+	}
+	return 0;
+}
+
+static void mtrr_restore(void)
+{
+	int i;
+
+	for (i = 0; i < num_var_ranges; i++) {
+		if (mtrr_value[i].lsize) {
+			mtrr_if->set(i, mtrr_value[i].lbase,
+				     mtrr_value[i].lsize,
+				     mtrr_value[i].ltype);
+		}
+	}
+}
+
+static struct syscore_ops mtrr_syscore_ops = {
+	.suspend	= mtrr_save,
+	.resume		= mtrr_restore,
+};
+
+void mtrr_register_syscore(void)
+{
+	mtrr_value = kcalloc(num_var_ranges, sizeof(*mtrr_value), GFP_KERNEL);
+
+	/*
+	 * The CPU has no MTRR and seems to not support SMP. They have
+	 * specific drivers, we use a tricky method to support
+	 * suspend/resume for them.
+	 *
+	 * TBD: is there any system with such CPU which supports
+	 * suspend/resume? If no, we should remove the code.
+	 */
+	register_syscore_ops(&mtrr_syscore_ops);
+}
diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.c b/arch/x86/kernel/cpu/mtrr/mtrr.c
new file mode 100644
index 0000000000..767bf1c71a
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/mtrr.c
@@ -0,0 +1,640 @@
+/*  Generic MTRR (Memory Type Range Register) driver.
+
+    Copyright (C) 1997-2000  Richard Gooch
+    Copyright (c) 2002	     Patrick Mochel
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Library General Public
+    License as published by the Free Software Foundation; either
+    version 2 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Library General Public License for more details.
+
+    You should have received a copy of the GNU Library General Public
+    License along with this library; if not, write to the Free
+    Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+    Richard Gooch may be reached by email at  rgooch@atnf.csiro.au
+    The postal address is:
+      Richard Gooch, c/o ATNF, P. O. Box 76, Epping, N.S.W., 2121, Australia.
+
+    Source: "Pentium Pro Family Developer's Manual, Volume 3:
+    Operating System Writer's Guide" (Intel document number 242692),
+    section 11.11.7
+
+    This was cleaned and made readable by Patrick Mochel <mochel@osdl.org>
+    on 6-7 March 2002.
+    Source: Intel Architecture Software Developers Manual, Volume 3:
+    System Programming Guide; Section 9.11. (1997 edition - PPro).
+*/
+
+#include <linux/types.h> /* FIXME: kvm_para.h needs this */
+
+#include <linux/stop_machine.h>
+#include <linux/kvm_para.h>
+#include <linux/uaccess.h>
+#include <linux/export.h>
+#include <linux/mutex.h>
+#include <linux/init.h>
+#include <linux/sort.h>
+#include <linux/cpu.h>
+#include <linux/pci.h>
+#include <linux/smp.h>
+#include <linux/syscore_ops.h>
+#include <linux/rcupdate.h>
+
+#include <asm/cacheinfo.h>
+#include <asm/cpufeature.h>
+#include <asm/e820/api.h>
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+#include <asm/memtype.h>
+
+#include "mtrr.h"
+
+/* arch_phys_wc_add returns an MTRR register index plus this offset. */
+#define MTRR_TO_PHYS_WC_OFFSET 1000
+
+u32 num_var_ranges;
+
+unsigned int mtrr_usage_table[MTRR_MAX_VAR_RANGES];
+DEFINE_MUTEX(mtrr_mutex);
+
+const struct mtrr_ops *mtrr_if;
+
+/*  Returns non-zero if we have the write-combining memory type  */
+static int have_wrcomb(void)
+{
+	struct pci_dev *dev;
+
+	dev = pci_get_class(PCI_CLASS_BRIDGE_HOST << 8, NULL);
+	if (dev != NULL) {
+		/*
+		 * ServerWorks LE chipsets < rev 6 have problems with
+		 * write-combining. Don't allow it and leave room for other
+		 * chipsets to be tagged
+		 */
+		if (dev->vendor == PCI_VENDOR_ID_SERVERWORKS &&
+		    dev->device == PCI_DEVICE_ID_SERVERWORKS_LE &&
+		    dev->revision <= 5) {
+			pr_info("Serverworks LE rev < 6 detected. Write-combining disabled.\n");
+			pci_dev_put(dev);
+			return 0;
+		}
+		/*
+		 * Intel 450NX errata # 23. Non ascending cacheline evictions to
+		 * write combining memory may resulting in data corruption
+		 */
+		if (dev->vendor == PCI_VENDOR_ID_INTEL &&
+		    dev->device == PCI_DEVICE_ID_INTEL_82451NX) {
+			pr_info("Intel 450NX MMC detected. Write-combining disabled.\n");
+			pci_dev_put(dev);
+			return 0;
+		}
+		pci_dev_put(dev);
+	}
+	return mtrr_if->have_wrcomb ? mtrr_if->have_wrcomb() : 0;
+}
+
+static void __init init_table(void)
+{
+	int i, max;
+
+	max = num_var_ranges;
+	for (i = 0; i < max; i++)
+		mtrr_usage_table[i] = 1;
+}
+
+struct set_mtrr_data {
+	unsigned long	smp_base;
+	unsigned long	smp_size;
+	unsigned int	smp_reg;
+	mtrr_type	smp_type;
+};
+
+/**
+ * mtrr_rendezvous_handler - Work done in the synchronization handler. Executed
+ * by all the CPUs.
+ * @info: pointer to mtrr configuration data
+ *
+ * Returns nothing.
+ */
+static int mtrr_rendezvous_handler(void *info)
+{
+	struct set_mtrr_data *data = info;
+
+	mtrr_if->set(data->smp_reg, data->smp_base,
+		     data->smp_size, data->smp_type);
+	return 0;
+}
+
+static inline int types_compatible(mtrr_type type1, mtrr_type type2)
+{
+	return type1 == MTRR_TYPE_UNCACHABLE ||
+	       type2 == MTRR_TYPE_UNCACHABLE ||
+	       (type1 == MTRR_TYPE_WRTHROUGH && type2 == MTRR_TYPE_WRBACK) ||
+	       (type1 == MTRR_TYPE_WRBACK && type2 == MTRR_TYPE_WRTHROUGH);
+}
+
+/**
+ * set_mtrr - update mtrrs on all processors
+ * @reg:	mtrr in question
+ * @base:	mtrr base
+ * @size:	mtrr size
+ * @type:	mtrr type
+ *
+ * This is kinda tricky, but fortunately, Intel spelled it out for us cleanly:
+ *
+ * 1. Queue work to do the following on all processors:
+ * 2. Disable Interrupts
+ * 3. Wait for all procs to do so
+ * 4. Enter no-fill cache mode
+ * 5. Flush caches
+ * 6. Clear PGE bit
+ * 7. Flush all TLBs
+ * 8. Disable all range registers
+ * 9. Update the MTRRs
+ * 10. Enable all range registers
+ * 11. Flush all TLBs and caches again
+ * 12. Enter normal cache mode and reenable caching
+ * 13. Set PGE
+ * 14. Wait for buddies to catch up
+ * 15. Enable interrupts.
+ *
+ * What does that mean for us? Well, stop_machine() will ensure that
+ * the rendezvous handler is started on each CPU. And in lockstep they
+ * do the state transition of disabling interrupts, updating MTRR's
+ * (the CPU vendors may each do it differently, so we call mtrr_if->set()
+ * callback and let them take care of it.) and enabling interrupts.
+ *
+ * Note that the mechanism is the same for UP systems, too; all the SMP stuff
+ * becomes nops.
+ */
+static void set_mtrr(unsigned int reg, unsigned long base, unsigned long size,
+		     mtrr_type type)
+{
+	struct set_mtrr_data data = { .smp_reg = reg,
+				      .smp_base = base,
+				      .smp_size = size,
+				      .smp_type = type
+				    };
+
+	stop_machine_cpuslocked(mtrr_rendezvous_handler, &data, cpu_online_mask);
+
+	generic_rebuild_map();
+}
+
+/**
+ * mtrr_add_page - Add a memory type region
+ * @base: Physical base address of region in pages (in units of 4 kB!)
+ * @size: Physical size of region in pages (4 kB)
+ * @type: Type of MTRR desired
+ * @increment: If this is true do usage counting on the region
+ *
+ * Memory type region registers control the caching on newer Intel and
+ * non Intel processors. This function allows drivers to request an
+ * MTRR is added. The details and hardware specifics of each processor's
+ * implementation are hidden from the caller, but nevertheless the
+ * caller should expect to need to provide a power of two size on an
+ * equivalent power of two boundary.
+ *
+ * If the region cannot be added either because all regions are in use
+ * or the CPU cannot support it a negative value is returned. On success
+ * the register number for this entry is returned, but should be treated
+ * as a cookie only.
+ *
+ * On a multiprocessor machine the changes are made to all processors.
+ * This is required on x86 by the Intel processors.
+ *
+ * The available types are
+ *
+ * %MTRR_TYPE_UNCACHABLE - No caching
+ *
+ * %MTRR_TYPE_WRBACK - Write data back in bursts whenever
+ *
+ * %MTRR_TYPE_WRCOMB - Write data back soon but allow bursts
+ *
+ * %MTRR_TYPE_WRTHROUGH - Cache reads but not writes
+ *
+ * BUGS: Needs a quiet flag for the cases where drivers do not mind
+ * failures and do not wish system log messages to be sent.
+ */
+int mtrr_add_page(unsigned long base, unsigned long size,
+		  unsigned int type, bool increment)
+{
+	unsigned long lbase, lsize;
+	int i, replace, error;
+	mtrr_type ltype;
+
+	if (!mtrr_enabled())
+		return -ENXIO;
+
+	error = mtrr_if->validate_add_page(base, size, type);
+	if (error)
+		return error;
+
+	if (type >= MTRR_NUM_TYPES) {
+		pr_warn("type: %u invalid\n", type);
+		return -EINVAL;
+	}
+
+	/* If the type is WC, check that this processor supports it */
+	if ((type == MTRR_TYPE_WRCOMB) && !have_wrcomb()) {
+		pr_warn("your processor doesn't support write-combining\n");
+		return -ENOSYS;
+	}
+
+	if (!size) {
+		pr_warn("zero sized request\n");
+		return -EINVAL;
+	}
+
+	if ((base | (base + size - 1)) >>
+	    (boot_cpu_data.x86_phys_bits - PAGE_SHIFT)) {
+		pr_warn("base or size exceeds the MTRR width\n");
+		return -EINVAL;
+	}
+
+	error = -EINVAL;
+	replace = -1;
+
+	/* No CPU hotplug when we change MTRR entries */
+	cpus_read_lock();
+
+	/* Search for existing MTRR  */
+	mutex_lock(&mtrr_mutex);
+	for (i = 0; i < num_var_ranges; ++i) {
+		mtrr_if->get(i, &lbase, &lsize, &ltype);
+		if (!lsize || base > lbase + lsize - 1 ||
+		    base + size - 1 < lbase)
+			continue;
+		/*
+		 * At this point we know there is some kind of
+		 * overlap/enclosure
+		 */
+		if (base < lbase || base + size - 1 > lbase + lsize - 1) {
+			if (base <= lbase &&
+			    base + size - 1 >= lbase + lsize - 1) {
+				/*  New region encloses an existing region  */
+				if (type == ltype) {
+					replace = replace == -1 ? i : -2;
+					continue;
+				} else if (types_compatible(type, ltype))
+					continue;
+			}
+			pr_warn("0x%lx000,0x%lx000 overlaps existing 0x%lx000,0x%lx000\n", base, size, lbase,
+				lsize);
+			goto out;
+		}
+		/* New region is enclosed by an existing region */
+		if (ltype != type) {
+			if (types_compatible(type, ltype))
+				continue;
+			pr_warn("type mismatch for %lx000,%lx000 old: %s new: %s\n",
+				base, size, mtrr_attrib_to_str(ltype),
+				mtrr_attrib_to_str(type));
+			goto out;
+		}
+		if (increment)
+			++mtrr_usage_table[i];
+		error = i;
+		goto out;
+	}
+	/* Search for an empty MTRR */
+	i = mtrr_if->get_free_region(base, size, replace);
+	if (i >= 0) {
+		set_mtrr(i, base, size, type);
+		if (likely(replace < 0)) {
+			mtrr_usage_table[i] = 1;
+		} else {
+			mtrr_usage_table[i] = mtrr_usage_table[replace];
+			if (increment)
+				mtrr_usage_table[i]++;
+			if (unlikely(replace != i)) {
+				set_mtrr(replace, 0, 0, 0);
+				mtrr_usage_table[replace] = 0;
+			}
+		}
+	} else {
+		pr_info("no more MTRRs available\n");
+	}
+	error = i;
+ out:
+	mutex_unlock(&mtrr_mutex);
+	cpus_read_unlock();
+	return error;
+}
+
+static int mtrr_check(unsigned long base, unsigned long size)
+{
+	if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1))) {
+		pr_warn("size and base must be multiples of 4 kiB\n");
+		Dprintk("size: 0x%lx  base: 0x%lx\n", size, base);
+		dump_stack();
+		return -1;
+	}
+	return 0;
+}
+
+/**
+ * mtrr_add - Add a memory type region
+ * @base: Physical base address of region
+ * @size: Physical size of region
+ * @type: Type of MTRR desired
+ * @increment: If this is true do usage counting on the region
+ *
+ * Memory type region registers control the caching on newer Intel and
+ * non Intel processors. This function allows drivers to request an
+ * MTRR is added. The details and hardware specifics of each processor's
+ * implementation are hidden from the caller, but nevertheless the
+ * caller should expect to need to provide a power of two size on an
+ * equivalent power of two boundary.
+ *
+ * If the region cannot be added either because all regions are in use
+ * or the CPU cannot support it a negative value is returned. On success
+ * the register number for this entry is returned, but should be treated
+ * as a cookie only.
+ *
+ * On a multiprocessor machine the changes are made to all processors.
+ * This is required on x86 by the Intel processors.
+ *
+ * The available types are
+ *
+ * %MTRR_TYPE_UNCACHABLE - No caching
+ *
+ * %MTRR_TYPE_WRBACK - Write data back in bursts whenever
+ *
+ * %MTRR_TYPE_WRCOMB - Write data back soon but allow bursts
+ *
+ * %MTRR_TYPE_WRTHROUGH - Cache reads but not writes
+ *
+ * BUGS: Needs a quiet flag for the cases where drivers do not mind
+ * failures and do not wish system log messages to be sent.
+ */
+int mtrr_add(unsigned long base, unsigned long size, unsigned int type,
+	     bool increment)
+{
+	if (!mtrr_enabled())
+		return -ENODEV;
+	if (mtrr_check(base, size))
+		return -EINVAL;
+	return mtrr_add_page(base >> PAGE_SHIFT, size >> PAGE_SHIFT, type,
+			     increment);
+}
+
+/**
+ * mtrr_del_page - delete a memory type region
+ * @reg: Register returned by mtrr_add
+ * @base: Physical base address
+ * @size: Size of region
+ *
+ * If register is supplied then base and size are ignored. This is
+ * how drivers should call it.
+ *
+ * Releases an MTRR region. If the usage count drops to zero the
+ * register is freed and the region returns to default state.
+ * On success the register is returned, on failure a negative error
+ * code.
+ */
+int mtrr_del_page(int reg, unsigned long base, unsigned long size)
+{
+	int i, max;
+	mtrr_type ltype;
+	unsigned long lbase, lsize;
+	int error = -EINVAL;
+
+	if (!mtrr_enabled())
+		return -ENODEV;
+
+	max = num_var_ranges;
+	/* No CPU hotplug when we change MTRR entries */
+	cpus_read_lock();
+	mutex_lock(&mtrr_mutex);
+	if (reg < 0) {
+		/*  Search for existing MTRR  */
+		for (i = 0; i < max; ++i) {
+			mtrr_if->get(i, &lbase, &lsize, &ltype);
+			if (lbase == base && lsize == size) {
+				reg = i;
+				break;
+			}
+		}
+		if (reg < 0) {
+			Dprintk("no MTRR for %lx000,%lx000 found\n", base, size);
+			goto out;
+		}
+	}
+	if (reg >= max) {
+		pr_warn("register: %d too big\n", reg);
+		goto out;
+	}
+	mtrr_if->get(reg, &lbase, &lsize, &ltype);
+	if (lsize < 1) {
+		pr_warn("MTRR %d not used\n", reg);
+		goto out;
+	}
+	if (mtrr_usage_table[reg] < 1) {
+		pr_warn("reg: %d has count=0\n", reg);
+		goto out;
+	}
+	if (--mtrr_usage_table[reg] < 1)
+		set_mtrr(reg, 0, 0, 0);
+	error = reg;
+ out:
+	mutex_unlock(&mtrr_mutex);
+	cpus_read_unlock();
+	return error;
+}
+
+/**
+ * mtrr_del - delete a memory type region
+ * @reg: Register returned by mtrr_add
+ * @base: Physical base address
+ * @size: Size of region
+ *
+ * If register is supplied then base and size are ignored. This is
+ * how drivers should call it.
+ *
+ * Releases an MTRR region. If the usage count drops to zero the
+ * register is freed and the region returns to default state.
+ * On success the register is returned, on failure a negative error
+ * code.
+ */
+int mtrr_del(int reg, unsigned long base, unsigned long size)
+{
+	if (!mtrr_enabled())
+		return -ENODEV;
+	if (mtrr_check(base, size))
+		return -EINVAL;
+	return mtrr_del_page(reg, base >> PAGE_SHIFT, size >> PAGE_SHIFT);
+}
+
+/**
+ * arch_phys_wc_add - add a WC MTRR and handle errors if PAT is unavailable
+ * @base: Physical base address
+ * @size: Size of region
+ *
+ * If PAT is available, this does nothing.  If PAT is unavailable, it
+ * attempts to add a WC MTRR covering size bytes starting at base and
+ * logs an error if this fails.
+ *
+ * The called should provide a power of two size on an equivalent
+ * power of two boundary.
+ *
+ * Drivers must store the return value to pass to mtrr_del_wc_if_needed,
+ * but drivers should not try to interpret that return value.
+ */
+int arch_phys_wc_add(unsigned long base, unsigned long size)
+{
+	int ret;
+
+	if (pat_enabled() || !mtrr_enabled())
+		return 0;  /* Success!  (We don't need to do anything.) */
+
+	ret = mtrr_add(base, size, MTRR_TYPE_WRCOMB, true);
+	if (ret < 0) {
+		pr_warn("Failed to add WC MTRR for [%p-%p]; performance may suffer.",
+			(void *)base, (void *)(base + size - 1));
+		return ret;
+	}
+	return ret + MTRR_TO_PHYS_WC_OFFSET;
+}
+EXPORT_SYMBOL(arch_phys_wc_add);
+
+/*
+ * arch_phys_wc_del - undoes arch_phys_wc_add
+ * @handle: Return value from arch_phys_wc_add
+ *
+ * This cleans up after mtrr_add_wc_if_needed.
+ *
+ * The API guarantees that mtrr_del_wc_if_needed(error code) and
+ * mtrr_del_wc_if_needed(0) do nothing.
+ */
+void arch_phys_wc_del(int handle)
+{
+	if (handle >= 1) {
+		WARN_ON(handle < MTRR_TO_PHYS_WC_OFFSET);
+		mtrr_del(handle - MTRR_TO_PHYS_WC_OFFSET, 0, 0);
+	}
+}
+EXPORT_SYMBOL(arch_phys_wc_del);
+
+/*
+ * arch_phys_wc_index - translates arch_phys_wc_add's return value
+ * @handle: Return value from arch_phys_wc_add
+ *
+ * This will turn the return value from arch_phys_wc_add into an mtrr
+ * index suitable for debugging.
+ *
+ * Note: There is no legitimate use for this function, except possibly
+ * in printk line.  Alas there is an illegitimate use in some ancient
+ * drm ioctls.
+ */
+int arch_phys_wc_index(int handle)
+{
+	if (handle < MTRR_TO_PHYS_WC_OFFSET)
+		return -1;
+	else
+		return handle - MTRR_TO_PHYS_WC_OFFSET;
+}
+EXPORT_SYMBOL_GPL(arch_phys_wc_index);
+
+int __initdata changed_by_mtrr_cleanup;
+
+/**
+ * mtrr_bp_init - initialize MTRRs on the boot CPU
+ *
+ * This needs to be called early; before any of the other CPUs are
+ * initialized (i.e. before smp_init()).
+ */
+void __init mtrr_bp_init(void)
+{
+	bool generic_mtrrs = cpu_feature_enabled(X86_FEATURE_MTRR);
+	const char *why = "(not available)";
+	unsigned long config, dummy;
+
+	phys_hi_rsvd = GENMASK(31, boot_cpu_data.x86_phys_bits - 32);
+
+	if (!generic_mtrrs && mtrr_state.enabled) {
+		/*
+		 * Software overwrite of MTRR state, only for generic case.
+		 * Note that X86_FEATURE_MTRR has been reset in this case.
+		 */
+		init_table();
+		mtrr_build_map();
+		pr_info("MTRRs set to read-only\n");
+
+		return;
+	}
+
+	if (generic_mtrrs)
+		mtrr_if = &generic_mtrr_ops;
+	else
+		mtrr_set_if();
+
+	if (mtrr_enabled()) {
+		/* Get the number of variable MTRR ranges. */
+		if (mtrr_if == &generic_mtrr_ops)
+			rdmsr(MSR_MTRRcap, config, dummy);
+		else
+			config = mtrr_if->var_regs;
+		num_var_ranges = config & MTRR_CAP_VCNT;
+
+		init_table();
+		if (mtrr_if == &generic_mtrr_ops) {
+			/* BIOS may override */
+			if (get_mtrr_state()) {
+				memory_caching_control |= CACHE_MTRR;
+				changed_by_mtrr_cleanup = mtrr_cleanup();
+				mtrr_build_map();
+			} else {
+				mtrr_if = NULL;
+				why = "by BIOS";
+			}
+		}
+	}
+
+	if (!mtrr_enabled())
+		pr_info("MTRRs disabled %s\n", why);
+}
+
+/**
+ * mtrr_save_state - Save current fixed-range MTRR state of the first
+ *	cpu in cpu_online_mask.
+ */
+void mtrr_save_state(void)
+{
+	int first_cpu;
+
+	if (!mtrr_enabled())
+		return;
+
+	first_cpu = cpumask_first(cpu_online_mask);
+	smp_call_function_single(first_cpu, mtrr_save_fixed_ranges, NULL, 1);
+}
+
+static int __init mtrr_init_finalize(void)
+{
+	/*
+	 * Map might exist if mtrr_overwrite_state() has been called or if
+	 * mtrr_enabled() returns true.
+	 */
+	mtrr_copy_map();
+
+	if (!mtrr_enabled())
+		return 0;
+
+	if (memory_caching_control & CACHE_MTRR) {
+		if (!changed_by_mtrr_cleanup)
+			mtrr_state_warn();
+		return 0;
+	}
+
+	mtrr_register_syscore();
+
+	return 0;
+}
+subsys_initcall(mtrr_init_finalize);
diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.h b/arch/x86/kernel/cpu/mtrr/mtrr.h
new file mode 100644
index 0000000000..5655f253d9
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/mtrr.h
@@ -0,0 +1,94 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * local MTRR defines.
+ */
+
+#include <linux/types.h>
+#include <linux/stddef.h>
+
+#define MTRR_CHANGE_MASK_FIXED     0x01
+#define MTRR_CHANGE_MASK_VARIABLE  0x02
+#define MTRR_CHANGE_MASK_DEFTYPE   0x04
+
+extern bool mtrr_debug;
+#define Dprintk(x...) do { if (mtrr_debug) pr_info(x); } while (0)
+
+extern unsigned int mtrr_usage_table[MTRR_MAX_VAR_RANGES];
+
+struct mtrr_ops {
+	u32	var_regs;
+	void	(*set)(unsigned int reg, unsigned long base,
+		       unsigned long size, mtrr_type type);
+	void	(*get)(unsigned int reg, unsigned long *base,
+		       unsigned long *size, mtrr_type *type);
+	int	(*get_free_region)(unsigned long base, unsigned long size,
+				   int replace_reg);
+	int	(*validate_add_page)(unsigned long base, unsigned long size,
+				     unsigned int type);
+	int	(*have_wrcomb)(void);
+};
+
+extern int generic_get_free_region(unsigned long base, unsigned long size,
+				   int replace_reg);
+extern int generic_validate_add_page(unsigned long base, unsigned long size,
+				     unsigned int type);
+
+extern const struct mtrr_ops generic_mtrr_ops;
+
+extern int positive_have_wrcomb(void);
+
+/* library functions for processor-specific routines */
+struct set_mtrr_context {
+	unsigned long	flags;
+	unsigned long	cr4val;
+	u32		deftype_lo;
+	u32		deftype_hi;
+	u32		ccr3;
+};
+
+void set_mtrr_done(struct set_mtrr_context *ctxt);
+void set_mtrr_cache_disable(struct set_mtrr_context *ctxt);
+void set_mtrr_prepare_save(struct set_mtrr_context *ctxt);
+
+void fill_mtrr_var_range(unsigned int index,
+		u32 base_lo, u32 base_hi, u32 mask_lo, u32 mask_hi);
+bool get_mtrr_state(void);
+
+extern const struct mtrr_ops *mtrr_if;
+extern struct mutex mtrr_mutex;
+
+extern unsigned int num_var_ranges;
+extern u64 mtrr_tom2;
+extern struct mtrr_state_type mtrr_state;
+extern u32 phys_hi_rsvd;
+
+void mtrr_state_warn(void);
+const char *mtrr_attrib_to_str(int x);
+void mtrr_wrmsr(unsigned, unsigned, unsigned);
+#ifdef CONFIG_X86_32
+void mtrr_set_if(void);
+void mtrr_register_syscore(void);
+#else
+static inline void mtrr_set_if(void) { }
+static inline void mtrr_register_syscore(void) { }
+#endif
+void mtrr_build_map(void);
+void mtrr_copy_map(void);
+
+/* CPU specific mtrr_ops vectors. */
+extern const struct mtrr_ops amd_mtrr_ops;
+extern const struct mtrr_ops cyrix_mtrr_ops;
+extern const struct mtrr_ops centaur_mtrr_ops;
+
+extern int changed_by_mtrr_cleanup;
+extern int mtrr_cleanup(void);
+
+/*
+ * Must be used by code which uses mtrr_if to call platform-specific
+ * MTRR manipulation functions.
+ */
+static inline bool mtrr_enabled(void)
+{
+	return !!mtrr_if;
+}
+void generic_rebuild_map(void);
diff --git a/arch/x86/kernel/cpu/perfctr-watchdog.c b/arch/x86/kernel/cpu/perfctr-watchdog.c
new file mode 100644
index 0000000000..7aecb2fc31
--- /dev/null
+++ b/arch/x86/kernel/cpu/perfctr-watchdog.c
@@ -0,0 +1,162 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * local apic based NMI watchdog for various CPUs.
+ *
+ * This file also handles reservation of performance counters for coordination
+ * with other users.
+ *
+ * Note that these events normally don't tick when the CPU idles. This means
+ * the frequency varies with CPU load.
+ *
+ * Original code for K7/P6 written by Keith Owens
+ *
+ */
+
+#include <linux/percpu.h>
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+#include <linux/smp.h>
+#include <asm/nmi.h>
+#include <linux/kprobes.h>
+
+#include <asm/apic.h>
+#include <asm/perf_event.h>
+
+/*
+ * this number is calculated from Intel's MSR_P4_CRU_ESCR5 register and it's
+ * offset from MSR_P4_BSU_ESCR0.
+ *
+ * It will be the max for all platforms (for now)
+ */
+#define NMI_MAX_COUNTER_BITS 66
+
+/*
+ * perfctr_nmi_owner tracks the ownership of the perfctr registers:
+ * evtsel_nmi_owner tracks the ownership of the event selection
+ * - different performance counters/ event selection may be reserved for
+ *   different subsystems this reservation system just tries to coordinate
+ *   things a little
+ */
+static DECLARE_BITMAP(perfctr_nmi_owner, NMI_MAX_COUNTER_BITS);
+static DECLARE_BITMAP(evntsel_nmi_owner, NMI_MAX_COUNTER_BITS);
+
+/* converts an msr to an appropriate reservation bit */
+static inline unsigned int nmi_perfctr_msr_to_bit(unsigned int msr)
+{
+	/* returns the bit offset of the performance counter register */
+	switch (boot_cpu_data.x86_vendor) {
+	case X86_VENDOR_HYGON:
+	case X86_VENDOR_AMD:
+		if (msr >= MSR_F15H_PERF_CTR)
+			return (msr - MSR_F15H_PERF_CTR) >> 1;
+		return msr - MSR_K7_PERFCTR0;
+	case X86_VENDOR_INTEL:
+		if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON))
+			return msr - MSR_ARCH_PERFMON_PERFCTR0;
+
+		switch (boot_cpu_data.x86) {
+		case 6:
+			return msr - MSR_P6_PERFCTR0;
+		case 11:
+			return msr - MSR_KNC_PERFCTR0;
+		case 15:
+			return msr - MSR_P4_BPU_PERFCTR0;
+		}
+		break;
+	case X86_VENDOR_ZHAOXIN:
+	case X86_VENDOR_CENTAUR:
+		return msr - MSR_ARCH_PERFMON_PERFCTR0;
+	}
+	return 0;
+}
+
+/*
+ * converts an msr to an appropriate reservation bit
+ * returns the bit offset of the event selection register
+ */
+static inline unsigned int nmi_evntsel_msr_to_bit(unsigned int msr)
+{
+	/* returns the bit offset of the event selection register */
+	switch (boot_cpu_data.x86_vendor) {
+	case X86_VENDOR_HYGON:
+	case X86_VENDOR_AMD:
+		if (msr >= MSR_F15H_PERF_CTL)
+			return (msr - MSR_F15H_PERF_CTL) >> 1;
+		return msr - MSR_K7_EVNTSEL0;
+	case X86_VENDOR_INTEL:
+		if (cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON))
+			return msr - MSR_ARCH_PERFMON_EVENTSEL0;
+
+		switch (boot_cpu_data.x86) {
+		case 6:
+			return msr - MSR_P6_EVNTSEL0;
+		case 11:
+			return msr - MSR_KNC_EVNTSEL0;
+		case 15:
+			return msr - MSR_P4_BSU_ESCR0;
+		}
+		break;
+	case X86_VENDOR_ZHAOXIN:
+	case X86_VENDOR_CENTAUR:
+		return msr - MSR_ARCH_PERFMON_EVENTSEL0;
+	}
+	return 0;
+
+}
+
+int reserve_perfctr_nmi(unsigned int msr)
+{
+	unsigned int counter;
+
+	counter = nmi_perfctr_msr_to_bit(msr);
+	/* register not managed by the allocator? */
+	if (counter > NMI_MAX_COUNTER_BITS)
+		return 1;
+
+	if (!test_and_set_bit(counter, perfctr_nmi_owner))
+		return 1;
+	return 0;
+}
+EXPORT_SYMBOL(reserve_perfctr_nmi);
+
+void release_perfctr_nmi(unsigned int msr)
+{
+	unsigned int counter;
+
+	counter = nmi_perfctr_msr_to_bit(msr);
+	/* register not managed by the allocator? */
+	if (counter > NMI_MAX_COUNTER_BITS)
+		return;
+
+	clear_bit(counter, perfctr_nmi_owner);
+}
+EXPORT_SYMBOL(release_perfctr_nmi);
+
+int reserve_evntsel_nmi(unsigned int msr)
+{
+	unsigned int counter;
+
+	counter = nmi_evntsel_msr_to_bit(msr);
+	/* register not managed by the allocator? */
+	if (counter > NMI_MAX_COUNTER_BITS)
+		return 1;
+
+	if (!test_and_set_bit(counter, evntsel_nmi_owner))
+		return 1;
+	return 0;
+}
+EXPORT_SYMBOL(reserve_evntsel_nmi);
+
+void release_evntsel_nmi(unsigned int msr)
+{
+	unsigned int counter;
+
+	counter = nmi_evntsel_msr_to_bit(msr);
+	/* register not managed by the allocator? */
+	if (counter > NMI_MAX_COUNTER_BITS)
+		return;
+
+	clear_bit(counter, evntsel_nmi_owner);
+}
+EXPORT_SYMBOL(release_evntsel_nmi);
diff --git a/arch/x86/kernel/cpu/powerflags.c b/arch/x86/kernel/cpu/powerflags.c
new file mode 100644
index 0000000000..fd6ec2aa03
--- /dev/null
+++ b/arch/x86/kernel/cpu/powerflags.c
@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Strings for the various x86 power flags
+ *
+ * This file must not contain any executable code.
+ */
+
+#include <asm/cpufeature.h>
+
+const char *const x86_power_flags[32] = {
+	"ts",	/* temperature sensor */
+	"fid",  /* frequency id control */
+	"vid",  /* voltage id control */
+	"ttp",  /* thermal trip */
+	"tm",	/* hardware thermal control */
+	"stc",	/* software thermal control */
+	"100mhzsteps", /* 100 MHz multiplier control */
+	"hwpstate", /* hardware P-state control */
+	"",	/* tsc invariant mapped to constant_tsc */
+	"cpb",  /* core performance boost */
+	"eff_freq_ro", /* Readonly aperf/mperf */
+	"proc_feedback", /* processor feedback interface */
+	"acc_power", /* accumulated power mechanism */
+};
diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c
new file mode 100644
index 0000000000..31c0e68f62
--- /dev/null
+++ b/arch/x86/kernel/cpu/proc.c
@@ -0,0 +1,200 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/smp.h>
+#include <linux/timex.h>
+#include <linux/string.h>
+#include <linux/seq_file.h>
+#include <linux/cpufreq.h>
+#include <asm/prctl.h>
+#include <linux/proc_fs.h>
+
+#include "cpu.h"
+
+#ifdef CONFIG_X86_VMX_FEATURE_NAMES
+extern const char * const x86_vmx_flags[NVMXINTS*32];
+#endif
+
+/*
+ *	Get CPU information for use by the procfs.
+ */
+static void show_cpuinfo_core(struct seq_file *m, struct cpuinfo_x86 *c,
+			      unsigned int cpu)
+{
+#ifdef CONFIG_SMP
+	seq_printf(m, "physical id\t: %d\n", c->phys_proc_id);
+	seq_printf(m, "siblings\t: %d\n",
+		   cpumask_weight(topology_core_cpumask(cpu)));
+	seq_printf(m, "core id\t\t: %d\n", c->cpu_core_id);
+	seq_printf(m, "cpu cores\t: %d\n", c->booted_cores);
+	seq_printf(m, "apicid\t\t: %d\n", c->apicid);
+	seq_printf(m, "initial apicid\t: %d\n", c->initial_apicid);
+#endif
+}
+
+#ifdef CONFIG_X86_32
+static void show_cpuinfo_misc(struct seq_file *m, struct cpuinfo_x86 *c)
+{
+	seq_printf(m,
+		   "fdiv_bug\t: %s\n"
+		   "f00f_bug\t: %s\n"
+		   "coma_bug\t: %s\n"
+		   "fpu\t\t: %s\n"
+		   "fpu_exception\t: %s\n"
+		   "cpuid level\t: %d\n"
+		   "wp\t\t: yes\n",
+		   boot_cpu_has_bug(X86_BUG_FDIV) ? "yes" : "no",
+		   boot_cpu_has_bug(X86_BUG_F00F) ? "yes" : "no",
+		   boot_cpu_has_bug(X86_BUG_COMA) ? "yes" : "no",
+		   boot_cpu_has(X86_FEATURE_FPU) ? "yes" : "no",
+		   boot_cpu_has(X86_FEATURE_FPU) ? "yes" : "no",
+		   c->cpuid_level);
+}
+#else
+static void show_cpuinfo_misc(struct seq_file *m, struct cpuinfo_x86 *c)
+{
+	seq_printf(m,
+		   "fpu\t\t: yes\n"
+		   "fpu_exception\t: yes\n"
+		   "cpuid level\t: %d\n"
+		   "wp\t\t: yes\n",
+		   c->cpuid_level);
+}
+#endif
+
+static int show_cpuinfo(struct seq_file *m, void *v)
+{
+	struct cpuinfo_x86 *c = v;
+	unsigned int cpu;
+	int i;
+
+	cpu = c->cpu_index;
+	seq_printf(m, "processor\t: %u\n"
+		   "vendor_id\t: %s\n"
+		   "cpu family\t: %d\n"
+		   "model\t\t: %u\n"
+		   "model name\t: %s\n",
+		   cpu,
+		   c->x86_vendor_id[0] ? c->x86_vendor_id : "unknown",
+		   c->x86,
+		   c->x86_model,
+		   c->x86_model_id[0] ? c->x86_model_id : "unknown");
+
+	if (c->x86_stepping || c->cpuid_level >= 0)
+		seq_printf(m, "stepping\t: %d\n", c->x86_stepping);
+	else
+		seq_puts(m, "stepping\t: unknown\n");
+	if (c->microcode)
+		seq_printf(m, "microcode\t: 0x%x\n", c->microcode);
+
+	if (cpu_has(c, X86_FEATURE_TSC)) {
+		unsigned int freq = arch_freq_get_on_cpu(cpu);
+
+		seq_printf(m, "cpu MHz\t\t: %u.%03u\n", freq / 1000, (freq % 1000));
+	}
+
+	/* Cache size */
+	if (c->x86_cache_size)
+		seq_printf(m, "cache size\t: %u KB\n", c->x86_cache_size);
+
+	show_cpuinfo_core(m, c, cpu);
+	show_cpuinfo_misc(m, c);
+
+	seq_puts(m, "flags\t\t:");
+	for (i = 0; i < 32*NCAPINTS; i++)
+		if (cpu_has(c, i) && x86_cap_flags[i] != NULL)
+			seq_printf(m, " %s", x86_cap_flags[i]);
+
+#ifdef CONFIG_X86_VMX_FEATURE_NAMES
+	if (cpu_has(c, X86_FEATURE_VMX) && c->vmx_capability[0]) {
+		seq_puts(m, "\nvmx flags\t:");
+		for (i = 0; i < 32*NVMXINTS; i++) {
+			if (test_bit(i, (unsigned long *)c->vmx_capability) &&
+			    x86_vmx_flags[i] != NULL)
+				seq_printf(m, " %s", x86_vmx_flags[i]);
+		}
+	}
+#endif
+
+	seq_puts(m, "\nbugs\t\t:");
+	for (i = 0; i < 32*NBUGINTS; i++) {
+		unsigned int bug_bit = 32*NCAPINTS + i;
+
+		if (cpu_has_bug(c, bug_bit) && x86_bug_flags[i])
+			seq_printf(m, " %s", x86_bug_flags[i]);
+	}
+
+	seq_printf(m, "\nbogomips\t: %lu.%02lu\n",
+		   c->loops_per_jiffy/(500000/HZ),
+		   (c->loops_per_jiffy/(5000/HZ)) % 100);
+
+#ifdef CONFIG_X86_64
+	if (c->x86_tlbsize > 0)
+		seq_printf(m, "TLB size\t: %d 4K pages\n", c->x86_tlbsize);
+#endif
+	seq_printf(m, "clflush size\t: %u\n", c->x86_clflush_size);
+	seq_printf(m, "cache_alignment\t: %d\n", c->x86_cache_alignment);
+	seq_printf(m, "address sizes\t: %u bits physical, %u bits virtual\n",
+		   c->x86_phys_bits, c->x86_virt_bits);
+
+	seq_puts(m, "power management:");
+	for (i = 0; i < 32; i++) {
+		if (c->x86_power & (1 << i)) {
+			if (i < ARRAY_SIZE(x86_power_flags) &&
+			    x86_power_flags[i])
+				seq_printf(m, "%s%s",
+					   x86_power_flags[i][0] ? " " : "",
+					   x86_power_flags[i]);
+			else
+				seq_printf(m, " [%d]", i);
+		}
+	}
+
+	seq_puts(m, "\n\n");
+
+	return 0;
+}
+
+static void *c_start(struct seq_file *m, loff_t *pos)
+{
+	*pos = cpumask_next(*pos - 1, cpu_online_mask);
+	if ((*pos) < nr_cpu_ids)
+		return &cpu_data(*pos);
+	return NULL;
+}
+
+static void *c_next(struct seq_file *m, void *v, loff_t *pos)
+{
+	(*pos)++;
+	return c_start(m, pos);
+}
+
+static void c_stop(struct seq_file *m, void *v)
+{
+}
+
+const struct seq_operations cpuinfo_op = {
+	.start	= c_start,
+	.next	= c_next,
+	.stop	= c_stop,
+	.show	= show_cpuinfo,
+};
+
+#ifdef CONFIG_X86_USER_SHADOW_STACK
+static void dump_x86_features(struct seq_file *m, unsigned long features)
+{
+	if (features & ARCH_SHSTK_SHSTK)
+		seq_puts(m, "shstk ");
+	if (features & ARCH_SHSTK_WRSS)
+		seq_puts(m, "wrss ");
+}
+
+void arch_proc_pid_thread_features(struct seq_file *m, struct task_struct *task)
+{
+	seq_puts(m, "x86_Thread_features:\t");
+	dump_x86_features(m, task->thread.features);
+	seq_putc(m, '\n');
+
+	seq_puts(m, "x86_Thread_features_locked:\t");
+	dump_x86_features(m, task->thread.features_locked);
+	seq_putc(m, '\n');
+}
+#endif /* CONFIG_X86_USER_SHADOW_STACK */
diff --git a/arch/x86/kernel/cpu/rdrand.c b/arch/x86/kernel/cpu/rdrand.c
new file mode 100644
index 0000000000..26a427fa84
--- /dev/null
+++ b/arch/x86/kernel/cpu/rdrand.c
@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * This file is part of the Linux kernel.
+ *
+ * Copyright (c) 2011, Intel Corporation
+ * Authors: Fenghua Yu <fenghua.yu@intel.com>,
+ *          H. Peter Anvin <hpa@linux.intel.com>
+ */
+
+#include <asm/processor.h>
+#include <asm/archrandom.h>
+#include <asm/sections.h>
+
+/*
+ * RDRAND has Built-In-Self-Test (BIST) that runs on every invocation.
+ * Run the instruction a few times as a sanity check. Also make sure
+ * it's not outputting the same value over and over, which has happened
+ * as a result of past CPU bugs.
+ *
+ * If it fails, it is simple to disable RDRAND and RDSEED here.
+ */
+
+void x86_init_rdrand(struct cpuinfo_x86 *c)
+{
+	enum { SAMPLES = 8, MIN_CHANGE = 5 };
+	unsigned long sample, prev;
+	bool failure = false;
+	size_t i, changed;
+
+	if (!cpu_has(c, X86_FEATURE_RDRAND))
+		return;
+
+	for (changed = 0, i = 0; i < SAMPLES; ++i) {
+		if (!rdrand_long(&sample)) {
+			failure = true;
+			break;
+		}
+		changed += i && sample != prev;
+		prev = sample;
+	}
+	if (changed < MIN_CHANGE)
+		failure = true;
+
+	if (failure) {
+		clear_cpu_cap(c, X86_FEATURE_RDRAND);
+		clear_cpu_cap(c, X86_FEATURE_RDSEED);
+		pr_emerg("RDRAND is not reliable on this platform; disabling.\n");
+	}
+}
diff --git a/arch/x86/kernel/cpu/resctrl/Makefile b/arch/x86/kernel/cpu/resctrl/Makefile
new file mode 100644
index 0000000000..4a06c37b9c
--- /dev/null
+++ b/arch/x86/kernel/cpu/resctrl/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_X86_CPU_RESCTRL)	+= core.o rdtgroup.o monitor.o
+obj-$(CONFIG_X86_CPU_RESCTRL)	+= ctrlmondata.o pseudo_lock.o
+CFLAGS_pseudo_lock.o = -I$(src)
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
new file mode 100644
index 0000000000..030d3b4097
--- /dev/null
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -0,0 +1,996 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Resource Director Technology(RDT)
+ * - Cache Allocation code.
+ *
+ * Copyright (C) 2016 Intel Corporation
+ *
+ * Authors:
+ *    Fenghua Yu <fenghua.yu@intel.com>
+ *    Tony Luck <tony.luck@intel.com>
+ *    Vikas Shivappa <vikas.shivappa@intel.com>
+ *
+ * More information about RDT be found in the Intel (R) x86 Architecture
+ * Software Developer Manual June 2016, volume 3, section 17.17.
+ */
+
+#define pr_fmt(fmt)	"resctrl: " fmt
+
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/cacheinfo.h>
+#include <linux/cpuhotplug.h>
+
+#include <asm/intel-family.h>
+#include <asm/resctrl.h>
+#include "internal.h"
+
+/* Mutex to protect rdtgroup access. */
+DEFINE_MUTEX(rdtgroup_mutex);
+
+/*
+ * The cached resctrl_pqr_state is strictly per CPU and can never be
+ * updated from a remote CPU. Functions which modify the state
+ * are called with interrupts disabled and no preemption, which
+ * is sufficient for the protection.
+ */
+DEFINE_PER_CPU(struct resctrl_pqr_state, pqr_state);
+
+/*
+ * Used to store the max resource name width and max resource data width
+ * to display the schemata in a tabular format
+ */
+int max_name_width, max_data_width;
+
+/*
+ * Global boolean for rdt_alloc which is true if any
+ * resource allocation is enabled.
+ */
+bool rdt_alloc_capable;
+
+static void
+mba_wrmsr_intel(struct rdt_domain *d, struct msr_param *m,
+		struct rdt_resource *r);
+static void
+cat_wrmsr(struct rdt_domain *d, struct msr_param *m, struct rdt_resource *r);
+static void
+mba_wrmsr_amd(struct rdt_domain *d, struct msr_param *m,
+	      struct rdt_resource *r);
+
+#define domain_init(id) LIST_HEAD_INIT(rdt_resources_all[id].r_resctrl.domains)
+
+struct rdt_hw_resource rdt_resources_all[] = {
+	[RDT_RESOURCE_L3] =
+	{
+		.r_resctrl = {
+			.rid			= RDT_RESOURCE_L3,
+			.name			= "L3",
+			.cache_level		= 3,
+			.domains		= domain_init(RDT_RESOURCE_L3),
+			.parse_ctrlval		= parse_cbm,
+			.format_str		= "%d=%0*x",
+			.fflags			= RFTYPE_RES_CACHE,
+		},
+		.msr_base		= MSR_IA32_L3_CBM_BASE,
+		.msr_update		= cat_wrmsr,
+	},
+	[RDT_RESOURCE_L2] =
+	{
+		.r_resctrl = {
+			.rid			= RDT_RESOURCE_L2,
+			.name			= "L2",
+			.cache_level		= 2,
+			.domains		= domain_init(RDT_RESOURCE_L2),
+			.parse_ctrlval		= parse_cbm,
+			.format_str		= "%d=%0*x",
+			.fflags			= RFTYPE_RES_CACHE,
+		},
+		.msr_base		= MSR_IA32_L2_CBM_BASE,
+		.msr_update		= cat_wrmsr,
+	},
+	[RDT_RESOURCE_MBA] =
+	{
+		.r_resctrl = {
+			.rid			= RDT_RESOURCE_MBA,
+			.name			= "MB",
+			.cache_level		= 3,
+			.domains		= domain_init(RDT_RESOURCE_MBA),
+			.parse_ctrlval		= parse_bw,
+			.format_str		= "%d=%*u",
+			.fflags			= RFTYPE_RES_MB,
+		},
+	},
+	[RDT_RESOURCE_SMBA] =
+	{
+		.r_resctrl = {
+			.rid			= RDT_RESOURCE_SMBA,
+			.name			= "SMBA",
+			.cache_level		= 3,
+			.domains		= domain_init(RDT_RESOURCE_SMBA),
+			.parse_ctrlval		= parse_bw,
+			.format_str		= "%d=%*u",
+			.fflags			= RFTYPE_RES_MB,
+		},
+	},
+};
+
+/*
+ * cache_alloc_hsw_probe() - Have to probe for Intel haswell server CPUs
+ * as they do not have CPUID enumeration support for Cache allocation.
+ * The check for Vendor/Family/Model is not enough to guarantee that
+ * the MSRs won't #GP fault because only the following SKUs support
+ * CAT:
+ *	Intel(R) Xeon(R)  CPU E5-2658  v3  @  2.20GHz
+ *	Intel(R) Xeon(R)  CPU E5-2648L v3  @  1.80GHz
+ *	Intel(R) Xeon(R)  CPU E5-2628L v3  @  2.00GHz
+ *	Intel(R) Xeon(R)  CPU E5-2618L v3  @  2.30GHz
+ *	Intel(R) Xeon(R)  CPU E5-2608L v3  @  2.00GHz
+ *	Intel(R) Xeon(R)  CPU E5-2658A v3  @  2.20GHz
+ *
+ * Probe by trying to write the first of the L3 cache mask registers
+ * and checking that the bits stick. Max CLOSids is always 4 and max cbm length
+ * is always 20 on hsw server parts. The minimum cache bitmask length
+ * allowed for HSW server is always 2 bits. Hardcode all of them.
+ */
+static inline void cache_alloc_hsw_probe(void)
+{
+	struct rdt_hw_resource *hw_res = &rdt_resources_all[RDT_RESOURCE_L3];
+	struct rdt_resource *r  = &hw_res->r_resctrl;
+	u32 l, h, max_cbm = BIT_MASK(20) - 1;
+
+	if (wrmsr_safe(MSR_IA32_L3_CBM_BASE, max_cbm, 0))
+		return;
+
+	rdmsr(MSR_IA32_L3_CBM_BASE, l, h);
+
+	/* If all the bits were set in MSR, return success */
+	if (l != max_cbm)
+		return;
+
+	hw_res->num_closid = 4;
+	r->default_ctrl = max_cbm;
+	r->cache.cbm_len = 20;
+	r->cache.shareable_bits = 0xc0000;
+	r->cache.min_cbm_bits = 2;
+	r->alloc_capable = true;
+
+	rdt_alloc_capable = true;
+}
+
+bool is_mba_sc(struct rdt_resource *r)
+{
+	if (!r)
+		return rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl.membw.mba_sc;
+
+	/*
+	 * The software controller support is only applicable to MBA resource.
+	 * Make sure to check for resource type.
+	 */
+	if (r->rid != RDT_RESOURCE_MBA)
+		return false;
+
+	return r->membw.mba_sc;
+}
+
+/*
+ * rdt_get_mb_table() - get a mapping of bandwidth(b/w) percentage values
+ * exposed to user interface and the h/w understandable delay values.
+ *
+ * The non-linear delay values have the granularity of power of two
+ * and also the h/w does not guarantee a curve for configured delay
+ * values vs. actual b/w enforced.
+ * Hence we need a mapping that is pre calibrated so the user can
+ * express the memory b/w as a percentage value.
+ */
+static inline bool rdt_get_mb_table(struct rdt_resource *r)
+{
+	/*
+	 * There are no Intel SKUs as of now to support non-linear delay.
+	 */
+	pr_info("MBA b/w map not implemented for cpu:%d, model:%d",
+		boot_cpu_data.x86, boot_cpu_data.x86_model);
+
+	return false;
+}
+
+static bool __get_mem_config_intel(struct rdt_resource *r)
+{
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+	union cpuid_0x10_3_eax eax;
+	union cpuid_0x10_x_edx edx;
+	u32 ebx, ecx, max_delay;
+
+	cpuid_count(0x00000010, 3, &eax.full, &ebx, &ecx, &edx.full);
+	hw_res->num_closid = edx.split.cos_max + 1;
+	max_delay = eax.split.max_delay + 1;
+	r->default_ctrl = MAX_MBA_BW;
+	r->membw.arch_needs_linear = true;
+	if (ecx & MBA_IS_LINEAR) {
+		r->membw.delay_linear = true;
+		r->membw.min_bw = MAX_MBA_BW - max_delay;
+		r->membw.bw_gran = MAX_MBA_BW - max_delay;
+	} else {
+		if (!rdt_get_mb_table(r))
+			return false;
+		r->membw.arch_needs_linear = false;
+	}
+	r->data_width = 3;
+
+	if (boot_cpu_has(X86_FEATURE_PER_THREAD_MBA))
+		r->membw.throttle_mode = THREAD_THROTTLE_PER_THREAD;
+	else
+		r->membw.throttle_mode = THREAD_THROTTLE_MAX;
+	thread_throttle_mode_init();
+
+	r->alloc_capable = true;
+
+	return true;
+}
+
+static bool __rdt_get_mem_config_amd(struct rdt_resource *r)
+{
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+	union cpuid_0x10_3_eax eax;
+	union cpuid_0x10_x_edx edx;
+	u32 ebx, ecx, subleaf;
+
+	/*
+	 * Query CPUID_Fn80000020_EDX_x01 for MBA and
+	 * CPUID_Fn80000020_EDX_x02 for SMBA
+	 */
+	subleaf = (r->rid == RDT_RESOURCE_SMBA) ? 2 :  1;
+
+	cpuid_count(0x80000020, subleaf, &eax.full, &ebx, &ecx, &edx.full);
+	hw_res->num_closid = edx.split.cos_max + 1;
+	r->default_ctrl = MAX_MBA_BW_AMD;
+
+	/* AMD does not use delay */
+	r->membw.delay_linear = false;
+	r->membw.arch_needs_linear = false;
+
+	/*
+	 * AMD does not use memory delay throttle model to control
+	 * the allocation like Intel does.
+	 */
+	r->membw.throttle_mode = THREAD_THROTTLE_UNDEFINED;
+	r->membw.min_bw = 0;
+	r->membw.bw_gran = 1;
+	/* Max value is 2048, Data width should be 4 in decimal */
+	r->data_width = 4;
+
+	r->alloc_capable = true;
+
+	return true;
+}
+
+static void rdt_get_cache_alloc_cfg(int idx, struct rdt_resource *r)
+{
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+	union cpuid_0x10_1_eax eax;
+	union cpuid_0x10_x_edx edx;
+	u32 ebx, ecx;
+
+	cpuid_count(0x00000010, idx, &eax.full, &ebx, &ecx, &edx.full);
+	hw_res->num_closid = edx.split.cos_max + 1;
+	r->cache.cbm_len = eax.split.cbm_len + 1;
+	r->default_ctrl = BIT_MASK(eax.split.cbm_len + 1) - 1;
+	r->cache.shareable_bits = ebx & r->default_ctrl;
+	r->data_width = (r->cache.cbm_len + 3) / 4;
+	r->alloc_capable = true;
+}
+
+static void rdt_get_cdp_config(int level)
+{
+	/*
+	 * By default, CDP is disabled. CDP can be enabled by mount parameter
+	 * "cdp" during resctrl file system mount time.
+	 */
+	rdt_resources_all[level].cdp_enabled = false;
+	rdt_resources_all[level].r_resctrl.cdp_capable = true;
+}
+
+static void rdt_get_cdp_l3_config(void)
+{
+	rdt_get_cdp_config(RDT_RESOURCE_L3);
+}
+
+static void rdt_get_cdp_l2_config(void)
+{
+	rdt_get_cdp_config(RDT_RESOURCE_L2);
+}
+
+static void
+mba_wrmsr_amd(struct rdt_domain *d, struct msr_param *m, struct rdt_resource *r)
+{
+	unsigned int i;
+	struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+
+	for (i = m->low; i < m->high; i++)
+		wrmsrl(hw_res->msr_base + i, hw_dom->ctrl_val[i]);
+}
+
+/*
+ * Map the memory b/w percentage value to delay values
+ * that can be written to QOS_MSRs.
+ * There are currently no SKUs which support non linear delay values.
+ */
+static u32 delay_bw_map(unsigned long bw, struct rdt_resource *r)
+{
+	if (r->membw.delay_linear)
+		return MAX_MBA_BW - bw;
+
+	pr_warn_once("Non Linear delay-bw map not supported but queried\n");
+	return r->default_ctrl;
+}
+
+static void
+mba_wrmsr_intel(struct rdt_domain *d, struct msr_param *m,
+		struct rdt_resource *r)
+{
+	unsigned int i;
+	struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+
+	/*  Write the delay values for mba. */
+	for (i = m->low; i < m->high; i++)
+		wrmsrl(hw_res->msr_base + i, delay_bw_map(hw_dom->ctrl_val[i], r));
+}
+
+static void
+cat_wrmsr(struct rdt_domain *d, struct msr_param *m, struct rdt_resource *r)
+{
+	unsigned int i;
+	struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+
+	for (i = m->low; i < m->high; i++)
+		wrmsrl(hw_res->msr_base + i, hw_dom->ctrl_val[i]);
+}
+
+struct rdt_domain *get_domain_from_cpu(int cpu, struct rdt_resource *r)
+{
+	struct rdt_domain *d;
+
+	list_for_each_entry(d, &r->domains, list) {
+		/* Find the domain that contains this CPU */
+		if (cpumask_test_cpu(cpu, &d->cpu_mask))
+			return d;
+	}
+
+	return NULL;
+}
+
+u32 resctrl_arch_get_num_closid(struct rdt_resource *r)
+{
+	return resctrl_to_arch_res(r)->num_closid;
+}
+
+void rdt_ctrl_update(void *arg)
+{
+	struct msr_param *m = arg;
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(m->res);
+	struct rdt_resource *r = m->res;
+	int cpu = smp_processor_id();
+	struct rdt_domain *d;
+
+	d = get_domain_from_cpu(cpu, r);
+	if (d) {
+		hw_res->msr_update(d, m, r);
+		return;
+	}
+	pr_warn_once("cpu %d not found in any domain for resource %s\n",
+		     cpu, r->name);
+}
+
+/*
+ * rdt_find_domain - Find a domain in a resource that matches input resource id
+ *
+ * Search resource r's domain list to find the resource id. If the resource
+ * id is found in a domain, return the domain. Otherwise, if requested by
+ * caller, return the first domain whose id is bigger than the input id.
+ * The domain list is sorted by id in ascending order.
+ */
+struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id,
+				   struct list_head **pos)
+{
+	struct rdt_domain *d;
+	struct list_head *l;
+
+	if (id < 0)
+		return ERR_PTR(-ENODEV);
+
+	list_for_each(l, &r->domains) {
+		d = list_entry(l, struct rdt_domain, list);
+		/* When id is found, return its domain. */
+		if (id == d->id)
+			return d;
+		/* Stop searching when finding id's position in sorted list. */
+		if (id < d->id)
+			break;
+	}
+
+	if (pos)
+		*pos = l;
+
+	return NULL;
+}
+
+static void setup_default_ctrlval(struct rdt_resource *r, u32 *dc)
+{
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+	int i;
+
+	/*
+	 * Initialize the Control MSRs to having no control.
+	 * For Cache Allocation: Set all bits in cbm
+	 * For Memory Allocation: Set b/w requested to 100%
+	 */
+	for (i = 0; i < hw_res->num_closid; i++, dc++)
+		*dc = r->default_ctrl;
+}
+
+static void domain_free(struct rdt_hw_domain *hw_dom)
+{
+	kfree(hw_dom->arch_mbm_total);
+	kfree(hw_dom->arch_mbm_local);
+	kfree(hw_dom->ctrl_val);
+	kfree(hw_dom);
+}
+
+static int domain_setup_ctrlval(struct rdt_resource *r, struct rdt_domain *d)
+{
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+	struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);
+	struct msr_param m;
+	u32 *dc;
+
+	dc = kmalloc_array(hw_res->num_closid, sizeof(*hw_dom->ctrl_val),
+			   GFP_KERNEL);
+	if (!dc)
+		return -ENOMEM;
+
+	hw_dom->ctrl_val = dc;
+	setup_default_ctrlval(r, dc);
+
+	m.low = 0;
+	m.high = hw_res->num_closid;
+	hw_res->msr_update(d, &m, r);
+	return 0;
+}
+
+/**
+ * arch_domain_mbm_alloc() - Allocate arch private storage for the MBM counters
+ * @num_rmid:	The size of the MBM counter array
+ * @hw_dom:	The domain that owns the allocated arrays
+ */
+static int arch_domain_mbm_alloc(u32 num_rmid, struct rdt_hw_domain *hw_dom)
+{
+	size_t tsize;
+
+	if (is_mbm_total_enabled()) {
+		tsize = sizeof(*hw_dom->arch_mbm_total);
+		hw_dom->arch_mbm_total = kcalloc(num_rmid, tsize, GFP_KERNEL);
+		if (!hw_dom->arch_mbm_total)
+			return -ENOMEM;
+	}
+	if (is_mbm_local_enabled()) {
+		tsize = sizeof(*hw_dom->arch_mbm_local);
+		hw_dom->arch_mbm_local = kcalloc(num_rmid, tsize, GFP_KERNEL);
+		if (!hw_dom->arch_mbm_local) {
+			kfree(hw_dom->arch_mbm_total);
+			hw_dom->arch_mbm_total = NULL;
+			return -ENOMEM;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * domain_add_cpu - Add a cpu to a resource's domain list.
+ *
+ * If an existing domain in the resource r's domain list matches the cpu's
+ * resource id, add the cpu in the domain.
+ *
+ * Otherwise, a new domain is allocated and inserted into the right position
+ * in the domain list sorted by id in ascending order.
+ *
+ * The order in the domain list is visible to users when we print entries
+ * in the schemata file and schemata input is validated to have the same order
+ * as this list.
+ */
+static void domain_add_cpu(int cpu, struct rdt_resource *r)
+{
+	int id = get_cpu_cacheinfo_id(cpu, r->cache_level);
+	struct list_head *add_pos = NULL;
+	struct rdt_hw_domain *hw_dom;
+	struct rdt_domain *d;
+	int err;
+
+	d = rdt_find_domain(r, id, &add_pos);
+	if (IS_ERR(d)) {
+		pr_warn("Couldn't find cache id for CPU %d\n", cpu);
+		return;
+	}
+
+	if (d) {
+		cpumask_set_cpu(cpu, &d->cpu_mask);
+		if (r->cache.arch_has_per_cpu_cfg)
+			rdt_domain_reconfigure_cdp(r);
+		return;
+	}
+
+	hw_dom = kzalloc_node(sizeof(*hw_dom), GFP_KERNEL, cpu_to_node(cpu));
+	if (!hw_dom)
+		return;
+
+	d = &hw_dom->d_resctrl;
+	d->id = id;
+	cpumask_set_cpu(cpu, &d->cpu_mask);
+
+	rdt_domain_reconfigure_cdp(r);
+
+	if (r->alloc_capable && domain_setup_ctrlval(r, d)) {
+		domain_free(hw_dom);
+		return;
+	}
+
+	if (r->mon_capable && arch_domain_mbm_alloc(r->num_rmid, hw_dom)) {
+		domain_free(hw_dom);
+		return;
+	}
+
+	list_add_tail(&d->list, add_pos);
+
+	err = resctrl_online_domain(r, d);
+	if (err) {
+		list_del(&d->list);
+		domain_free(hw_dom);
+	}
+}
+
+static void domain_remove_cpu(int cpu, struct rdt_resource *r)
+{
+	int id = get_cpu_cacheinfo_id(cpu, r->cache_level);
+	struct rdt_hw_domain *hw_dom;
+	struct rdt_domain *d;
+
+	d = rdt_find_domain(r, id, NULL);
+	if (IS_ERR_OR_NULL(d)) {
+		pr_warn("Couldn't find cache id for CPU %d\n", cpu);
+		return;
+	}
+	hw_dom = resctrl_to_arch_dom(d);
+
+	cpumask_clear_cpu(cpu, &d->cpu_mask);
+	if (cpumask_empty(&d->cpu_mask)) {
+		resctrl_offline_domain(r, d);
+		list_del(&d->list);
+
+		/*
+		 * rdt_domain "d" is going to be freed below, so clear
+		 * its pointer from pseudo_lock_region struct.
+		 */
+		if (d->plr)
+			d->plr->d = NULL;
+		domain_free(hw_dom);
+
+		return;
+	}
+
+	if (r == &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl) {
+		if (is_mbm_enabled() && cpu == d->mbm_work_cpu) {
+			cancel_delayed_work(&d->mbm_over);
+			mbm_setup_overflow_handler(d, 0);
+		}
+		if (is_llc_occupancy_enabled() && cpu == d->cqm_work_cpu &&
+		    has_busy_rmid(r, d)) {
+			cancel_delayed_work(&d->cqm_limbo);
+			cqm_setup_limbo_handler(d, 0);
+		}
+	}
+}
+
+static void clear_closid_rmid(int cpu)
+{
+	struct resctrl_pqr_state *state = this_cpu_ptr(&pqr_state);
+
+	state->default_closid = 0;
+	state->default_rmid = 0;
+	state->cur_closid = 0;
+	state->cur_rmid = 0;
+	wrmsr(MSR_IA32_PQR_ASSOC, 0, 0);
+}
+
+static int resctrl_online_cpu(unsigned int cpu)
+{
+	struct rdt_resource *r;
+
+	mutex_lock(&rdtgroup_mutex);
+	for_each_capable_rdt_resource(r)
+		domain_add_cpu(cpu, r);
+	/* The cpu is set in default rdtgroup after online. */
+	cpumask_set_cpu(cpu, &rdtgroup_default.cpu_mask);
+	clear_closid_rmid(cpu);
+	mutex_unlock(&rdtgroup_mutex);
+
+	return 0;
+}
+
+static void clear_childcpus(struct rdtgroup *r, unsigned int cpu)
+{
+	struct rdtgroup *cr;
+
+	list_for_each_entry(cr, &r->mon.crdtgrp_list, mon.crdtgrp_list) {
+		if (cpumask_test_and_clear_cpu(cpu, &cr->cpu_mask)) {
+			break;
+		}
+	}
+}
+
+static int resctrl_offline_cpu(unsigned int cpu)
+{
+	struct rdtgroup *rdtgrp;
+	struct rdt_resource *r;
+
+	mutex_lock(&rdtgroup_mutex);
+	for_each_capable_rdt_resource(r)
+		domain_remove_cpu(cpu, r);
+	list_for_each_entry(rdtgrp, &rdt_all_groups, rdtgroup_list) {
+		if (cpumask_test_and_clear_cpu(cpu, &rdtgrp->cpu_mask)) {
+			clear_childcpus(rdtgrp, cpu);
+			break;
+		}
+	}
+	clear_closid_rmid(cpu);
+	mutex_unlock(&rdtgroup_mutex);
+
+	return 0;
+}
+
+/*
+ * Choose a width for the resource name and resource data based on the
+ * resource that has widest name and cbm.
+ */
+static __init void rdt_init_padding(void)
+{
+	struct rdt_resource *r;
+
+	for_each_alloc_capable_rdt_resource(r) {
+		if (r->data_width > max_data_width)
+			max_data_width = r->data_width;
+	}
+}
+
+enum {
+	RDT_FLAG_CMT,
+	RDT_FLAG_MBM_TOTAL,
+	RDT_FLAG_MBM_LOCAL,
+	RDT_FLAG_L3_CAT,
+	RDT_FLAG_L3_CDP,
+	RDT_FLAG_L2_CAT,
+	RDT_FLAG_L2_CDP,
+	RDT_FLAG_MBA,
+	RDT_FLAG_SMBA,
+	RDT_FLAG_BMEC,
+};
+
+#define RDT_OPT(idx, n, f)	\
+[idx] = {			\
+	.name = n,		\
+	.flag = f		\
+}
+
+struct rdt_options {
+	char	*name;
+	int	flag;
+	bool	force_off, force_on;
+};
+
+static struct rdt_options rdt_options[]  __initdata = {
+	RDT_OPT(RDT_FLAG_CMT,	    "cmt",	X86_FEATURE_CQM_OCCUP_LLC),
+	RDT_OPT(RDT_FLAG_MBM_TOTAL, "mbmtotal", X86_FEATURE_CQM_MBM_TOTAL),
+	RDT_OPT(RDT_FLAG_MBM_LOCAL, "mbmlocal", X86_FEATURE_CQM_MBM_LOCAL),
+	RDT_OPT(RDT_FLAG_L3_CAT,    "l3cat",	X86_FEATURE_CAT_L3),
+	RDT_OPT(RDT_FLAG_L3_CDP,    "l3cdp",	X86_FEATURE_CDP_L3),
+	RDT_OPT(RDT_FLAG_L2_CAT,    "l2cat",	X86_FEATURE_CAT_L2),
+	RDT_OPT(RDT_FLAG_L2_CDP,    "l2cdp",	X86_FEATURE_CDP_L2),
+	RDT_OPT(RDT_FLAG_MBA,	    "mba",	X86_FEATURE_MBA),
+	RDT_OPT(RDT_FLAG_SMBA,	    "smba",	X86_FEATURE_SMBA),
+	RDT_OPT(RDT_FLAG_BMEC,	    "bmec",	X86_FEATURE_BMEC),
+};
+#define NUM_RDT_OPTIONS ARRAY_SIZE(rdt_options)
+
+static int __init set_rdt_options(char *str)
+{
+	struct rdt_options *o;
+	bool force_off;
+	char *tok;
+
+	if (*str == '=')
+		str++;
+	while ((tok = strsep(&str, ",")) != NULL) {
+		force_off = *tok == '!';
+		if (force_off)
+			tok++;
+		for (o = rdt_options; o < &rdt_options[NUM_RDT_OPTIONS]; o++) {
+			if (strcmp(tok, o->name) == 0) {
+				if (force_off)
+					o->force_off = true;
+				else
+					o->force_on = true;
+				break;
+			}
+		}
+	}
+	return 1;
+}
+__setup("rdt", set_rdt_options);
+
+bool __init rdt_cpu_has(int flag)
+{
+	bool ret = boot_cpu_has(flag);
+	struct rdt_options *o;
+
+	if (!ret)
+		return ret;
+
+	for (o = rdt_options; o < &rdt_options[NUM_RDT_OPTIONS]; o++) {
+		if (flag == o->flag) {
+			if (o->force_off)
+				ret = false;
+			if (o->force_on)
+				ret = true;
+			break;
+		}
+	}
+	return ret;
+}
+
+static __init bool get_mem_config(void)
+{
+	struct rdt_hw_resource *hw_res = &rdt_resources_all[RDT_RESOURCE_MBA];
+
+	if (!rdt_cpu_has(X86_FEATURE_MBA))
+		return false;
+
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
+		return __get_mem_config_intel(&hw_res->r_resctrl);
+	else if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+		return __rdt_get_mem_config_amd(&hw_res->r_resctrl);
+
+	return false;
+}
+
+static __init bool get_slow_mem_config(void)
+{
+	struct rdt_hw_resource *hw_res = &rdt_resources_all[RDT_RESOURCE_SMBA];
+
+	if (!rdt_cpu_has(X86_FEATURE_SMBA))
+		return false;
+
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+		return __rdt_get_mem_config_amd(&hw_res->r_resctrl);
+
+	return false;
+}
+
+static __init bool get_rdt_alloc_resources(void)
+{
+	struct rdt_resource *r;
+	bool ret = false;
+
+	if (rdt_alloc_capable)
+		return true;
+
+	if (!boot_cpu_has(X86_FEATURE_RDT_A))
+		return false;
+
+	if (rdt_cpu_has(X86_FEATURE_CAT_L3)) {
+		r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+		rdt_get_cache_alloc_cfg(1, r);
+		if (rdt_cpu_has(X86_FEATURE_CDP_L3))
+			rdt_get_cdp_l3_config();
+		ret = true;
+	}
+	if (rdt_cpu_has(X86_FEATURE_CAT_L2)) {
+		/* CPUID 0x10.2 fields are same format at 0x10.1 */
+		r = &rdt_resources_all[RDT_RESOURCE_L2].r_resctrl;
+		rdt_get_cache_alloc_cfg(2, r);
+		if (rdt_cpu_has(X86_FEATURE_CDP_L2))
+			rdt_get_cdp_l2_config();
+		ret = true;
+	}
+
+	if (get_mem_config())
+		ret = true;
+
+	if (get_slow_mem_config())
+		ret = true;
+
+	return ret;
+}
+
+static __init bool get_rdt_mon_resources(void)
+{
+	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+
+	if (rdt_cpu_has(X86_FEATURE_CQM_OCCUP_LLC))
+		rdt_mon_features |= (1 << QOS_L3_OCCUP_EVENT_ID);
+	if (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL))
+		rdt_mon_features |= (1 << QOS_L3_MBM_TOTAL_EVENT_ID);
+	if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL))
+		rdt_mon_features |= (1 << QOS_L3_MBM_LOCAL_EVENT_ID);
+
+	if (!rdt_mon_features)
+		return false;
+
+	return !rdt_get_mon_l3_config(r);
+}
+
+static __init void __check_quirks_intel(void)
+{
+	switch (boot_cpu_data.x86_model) {
+	case INTEL_FAM6_HASWELL_X:
+		if (!rdt_options[RDT_FLAG_L3_CAT].force_off)
+			cache_alloc_hsw_probe();
+		break;
+	case INTEL_FAM6_SKYLAKE_X:
+		if (boot_cpu_data.x86_stepping <= 4)
+			set_rdt_options("!cmt,!mbmtotal,!mbmlocal,!l3cat");
+		else
+			set_rdt_options("!l3cat");
+		fallthrough;
+	case INTEL_FAM6_BROADWELL_X:
+		intel_rdt_mbm_apply_quirk();
+		break;
+	}
+}
+
+static __init void check_quirks(void)
+{
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
+		__check_quirks_intel();
+}
+
+static __init bool get_rdt_resources(void)
+{
+	rdt_alloc_capable = get_rdt_alloc_resources();
+	rdt_mon_capable = get_rdt_mon_resources();
+
+	return (rdt_mon_capable || rdt_alloc_capable);
+}
+
+static __init void rdt_init_res_defs_intel(void)
+{
+	struct rdt_hw_resource *hw_res;
+	struct rdt_resource *r;
+
+	for_each_rdt_resource(r) {
+		hw_res = resctrl_to_arch_res(r);
+
+		if (r->rid == RDT_RESOURCE_L3 ||
+		    r->rid == RDT_RESOURCE_L2) {
+			r->cache.arch_has_sparse_bitmaps = false;
+			r->cache.arch_has_per_cpu_cfg = false;
+			r->cache.min_cbm_bits = 1;
+		} else if (r->rid == RDT_RESOURCE_MBA) {
+			hw_res->msr_base = MSR_IA32_MBA_THRTL_BASE;
+			hw_res->msr_update = mba_wrmsr_intel;
+		}
+	}
+}
+
+static __init void rdt_init_res_defs_amd(void)
+{
+	struct rdt_hw_resource *hw_res;
+	struct rdt_resource *r;
+
+	for_each_rdt_resource(r) {
+		hw_res = resctrl_to_arch_res(r);
+
+		if (r->rid == RDT_RESOURCE_L3 ||
+		    r->rid == RDT_RESOURCE_L2) {
+			r->cache.arch_has_sparse_bitmaps = true;
+			r->cache.arch_has_per_cpu_cfg = true;
+			r->cache.min_cbm_bits = 0;
+		} else if (r->rid == RDT_RESOURCE_MBA) {
+			hw_res->msr_base = MSR_IA32_MBA_BW_BASE;
+			hw_res->msr_update = mba_wrmsr_amd;
+		} else if (r->rid == RDT_RESOURCE_SMBA) {
+			hw_res->msr_base = MSR_IA32_SMBA_BW_BASE;
+			hw_res->msr_update = mba_wrmsr_amd;
+		}
+	}
+}
+
+static __init void rdt_init_res_defs(void)
+{
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
+		rdt_init_res_defs_intel();
+	else if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+		rdt_init_res_defs_amd();
+}
+
+static enum cpuhp_state rdt_online;
+
+/* Runs once on the BSP during boot. */
+void resctrl_cpu_detect(struct cpuinfo_x86 *c)
+{
+	if (!cpu_has(c, X86_FEATURE_CQM_LLC)) {
+		c->x86_cache_max_rmid  = -1;
+		c->x86_cache_occ_scale = -1;
+		c->x86_cache_mbm_width_offset = -1;
+		return;
+	}
+
+	/* will be overridden if occupancy monitoring exists */
+	c->x86_cache_max_rmid = cpuid_ebx(0xf);
+
+	if (cpu_has(c, X86_FEATURE_CQM_OCCUP_LLC) ||
+	    cpu_has(c, X86_FEATURE_CQM_MBM_TOTAL) ||
+	    cpu_has(c, X86_FEATURE_CQM_MBM_LOCAL)) {
+		u32 eax, ebx, ecx, edx;
+
+		/* QoS sub-leaf, EAX=0Fh, ECX=1 */
+		cpuid_count(0xf, 1, &eax, &ebx, &ecx, &edx);
+
+		c->x86_cache_max_rmid  = ecx;
+		c->x86_cache_occ_scale = ebx;
+		c->x86_cache_mbm_width_offset = eax & 0xff;
+
+		if (c->x86_vendor == X86_VENDOR_AMD && !c->x86_cache_mbm_width_offset)
+			c->x86_cache_mbm_width_offset = MBM_CNTR_WIDTH_OFFSET_AMD;
+	}
+}
+
+static int __init resctrl_late_init(void)
+{
+	struct rdt_resource *r;
+	int state, ret;
+
+	/*
+	 * Initialize functions(or definitions) that are different
+	 * between vendors here.
+	 */
+	rdt_init_res_defs();
+
+	check_quirks();
+
+	if (!get_rdt_resources())
+		return -ENODEV;
+
+	rdt_init_padding();
+
+	state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
+				  "x86/resctrl/cat:online:",
+				  resctrl_online_cpu, resctrl_offline_cpu);
+	if (state < 0)
+		return state;
+
+	ret = rdtgroup_init();
+	if (ret) {
+		cpuhp_remove_state(state);
+		return ret;
+	}
+	rdt_online = state;
+
+	for_each_alloc_capable_rdt_resource(r)
+		pr_info("%s allocation detected\n", r->name);
+
+	for_each_mon_capable_rdt_resource(r)
+		pr_info("%s monitoring detected\n", r->name);
+
+	return 0;
+}
+
+late_initcall(resctrl_late_init);
+
+static void __exit resctrl_exit(void)
+{
+	cpuhp_remove_state(rdt_online);
+	rdtgroup_exit();
+}
+
+__exitcall(resctrl_exit);
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
new file mode 100644
index 0000000000..b44c487727
--- /dev/null
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -0,0 +1,581 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Resource Director Technology(RDT)
+ * - Cache Allocation code.
+ *
+ * Copyright (C) 2016 Intel Corporation
+ *
+ * Authors:
+ *    Fenghua Yu <fenghua.yu@intel.com>
+ *    Tony Luck <tony.luck@intel.com>
+ *
+ * More information about RDT be found in the Intel (R) x86 Architecture
+ * Software Developer Manual June 2016, volume 3, section 17.17.
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/cpu.h>
+#include <linux/kernfs.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include "internal.h"
+
+/*
+ * Check whether MBA bandwidth percentage value is correct. The value is
+ * checked against the minimum and max bandwidth values specified by the
+ * hardware. The allocated bandwidth percentage is rounded to the next
+ * control step available on the hardware.
+ */
+static bool bw_validate(char *buf, unsigned long *data, struct rdt_resource *r)
+{
+	unsigned long bw;
+	int ret;
+
+	/*
+	 * Only linear delay values is supported for current Intel SKUs.
+	 */
+	if (!r->membw.delay_linear && r->membw.arch_needs_linear) {
+		rdt_last_cmd_puts("No support for non-linear MB domains\n");
+		return false;
+	}
+
+	ret = kstrtoul(buf, 10, &bw);
+	if (ret) {
+		rdt_last_cmd_printf("Non-decimal digit in MB value %s\n", buf);
+		return false;
+	}
+
+	if ((bw < r->membw.min_bw || bw > r->default_ctrl) &&
+	    !is_mba_sc(r)) {
+		rdt_last_cmd_printf("MB value %ld out of range [%d,%d]\n", bw,
+				    r->membw.min_bw, r->default_ctrl);
+		return false;
+	}
+
+	*data = roundup(bw, (unsigned long)r->membw.bw_gran);
+	return true;
+}
+
+int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s,
+	     struct rdt_domain *d)
+{
+	struct resctrl_staged_config *cfg;
+	u32 closid = data->rdtgrp->closid;
+	struct rdt_resource *r = s->res;
+	unsigned long bw_val;
+
+	cfg = &d->staged_config[s->conf_type];
+	if (cfg->have_new_ctrl) {
+		rdt_last_cmd_printf("Duplicate domain %d\n", d->id);
+		return -EINVAL;
+	}
+
+	if (!bw_validate(data->buf, &bw_val, r))
+		return -EINVAL;
+
+	if (is_mba_sc(r)) {
+		d->mbps_val[closid] = bw_val;
+		return 0;
+	}
+
+	cfg->new_ctrl = bw_val;
+	cfg->have_new_ctrl = true;
+
+	return 0;
+}
+
+/*
+ * Check whether a cache bit mask is valid.
+ * For Intel the SDM says:
+ *	Please note that all (and only) contiguous '1' combinations
+ *	are allowed (e.g. FFFFH, 0FF0H, 003CH, etc.).
+ * Additionally Haswell requires at least two bits set.
+ * AMD allows non-contiguous bitmasks.
+ */
+static bool cbm_validate(char *buf, u32 *data, struct rdt_resource *r)
+{
+	unsigned long first_bit, zero_bit, val;
+	unsigned int cbm_len = r->cache.cbm_len;
+	int ret;
+
+	ret = kstrtoul(buf, 16, &val);
+	if (ret) {
+		rdt_last_cmd_printf("Non-hex character in the mask %s\n", buf);
+		return false;
+	}
+
+	if ((r->cache.min_cbm_bits > 0 && val == 0) || val > r->default_ctrl) {
+		rdt_last_cmd_puts("Mask out of range\n");
+		return false;
+	}
+
+	first_bit = find_first_bit(&val, cbm_len);
+	zero_bit = find_next_zero_bit(&val, cbm_len, first_bit);
+
+	/* Are non-contiguous bitmaps allowed? */
+	if (!r->cache.arch_has_sparse_bitmaps &&
+	    (find_next_bit(&val, cbm_len, zero_bit) < cbm_len)) {
+		rdt_last_cmd_printf("The mask %lx has non-consecutive 1-bits\n", val);
+		return false;
+	}
+
+	if ((zero_bit - first_bit) < r->cache.min_cbm_bits) {
+		rdt_last_cmd_printf("Need at least %d bits in the mask\n",
+				    r->cache.min_cbm_bits);
+		return false;
+	}
+
+	*data = val;
+	return true;
+}
+
+/*
+ * Read one cache bit mask (hex). Check that it is valid for the current
+ * resource type.
+ */
+int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
+	      struct rdt_domain *d)
+{
+	struct rdtgroup *rdtgrp = data->rdtgrp;
+	struct resctrl_staged_config *cfg;
+	struct rdt_resource *r = s->res;
+	u32 cbm_val;
+
+	cfg = &d->staged_config[s->conf_type];
+	if (cfg->have_new_ctrl) {
+		rdt_last_cmd_printf("Duplicate domain %d\n", d->id);
+		return -EINVAL;
+	}
+
+	/*
+	 * Cannot set up more than one pseudo-locked region in a cache
+	 * hierarchy.
+	 */
+	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP &&
+	    rdtgroup_pseudo_locked_in_hierarchy(d)) {
+		rdt_last_cmd_puts("Pseudo-locked region in hierarchy\n");
+		return -EINVAL;
+	}
+
+	if (!cbm_validate(data->buf, &cbm_val, r))
+		return -EINVAL;
+
+	if ((rdtgrp->mode == RDT_MODE_EXCLUSIVE ||
+	     rdtgrp->mode == RDT_MODE_SHAREABLE) &&
+	    rdtgroup_cbm_overlaps_pseudo_locked(d, cbm_val)) {
+		rdt_last_cmd_puts("CBM overlaps with pseudo-locked region\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * The CBM may not overlap with the CBM of another closid if
+	 * either is exclusive.
+	 */
+	if (rdtgroup_cbm_overlaps(s, d, cbm_val, rdtgrp->closid, true)) {
+		rdt_last_cmd_puts("Overlaps with exclusive group\n");
+		return -EINVAL;
+	}
+
+	if (rdtgroup_cbm_overlaps(s, d, cbm_val, rdtgrp->closid, false)) {
+		if (rdtgrp->mode == RDT_MODE_EXCLUSIVE ||
+		    rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
+			rdt_last_cmd_puts("Overlaps with other group\n");
+			return -EINVAL;
+		}
+	}
+
+	cfg->new_ctrl = cbm_val;
+	cfg->have_new_ctrl = true;
+
+	return 0;
+}
+
+/*
+ * For each domain in this resource we expect to find a series of:
+ *	id=mask
+ * separated by ";". The "id" is in decimal, and must match one of
+ * the "id"s for this resource.
+ */
+static int parse_line(char *line, struct resctrl_schema *s,
+		      struct rdtgroup *rdtgrp)
+{
+	enum resctrl_conf_type t = s->conf_type;
+	struct resctrl_staged_config *cfg;
+	struct rdt_resource *r = s->res;
+	struct rdt_parse_data data;
+	char *dom = NULL, *id;
+	struct rdt_domain *d;
+	unsigned long dom_id;
+
+	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP &&
+	    (r->rid == RDT_RESOURCE_MBA || r->rid == RDT_RESOURCE_SMBA)) {
+		rdt_last_cmd_puts("Cannot pseudo-lock MBA resource\n");
+		return -EINVAL;
+	}
+
+next:
+	if (!line || line[0] == '\0')
+		return 0;
+	dom = strsep(&line, ";");
+	id = strsep(&dom, "=");
+	if (!dom || kstrtoul(id, 10, &dom_id)) {
+		rdt_last_cmd_puts("Missing '=' or non-numeric domain\n");
+		return -EINVAL;
+	}
+	dom = strim(dom);
+	list_for_each_entry(d, &r->domains, list) {
+		if (d->id == dom_id) {
+			data.buf = dom;
+			data.rdtgrp = rdtgrp;
+			if (r->parse_ctrlval(&data, s, d))
+				return -EINVAL;
+			if (rdtgrp->mode ==  RDT_MODE_PSEUDO_LOCKSETUP) {
+				cfg = &d->staged_config[t];
+				/*
+				 * In pseudo-locking setup mode and just
+				 * parsed a valid CBM that should be
+				 * pseudo-locked. Only one locked region per
+				 * resource group and domain so just do
+				 * the required initialization for single
+				 * region and return.
+				 */
+				rdtgrp->plr->s = s;
+				rdtgrp->plr->d = d;
+				rdtgrp->plr->cbm = cfg->new_ctrl;
+				d->plr = rdtgrp->plr;
+				return 0;
+			}
+			goto next;
+		}
+	}
+	return -EINVAL;
+}
+
+static u32 get_config_index(u32 closid, enum resctrl_conf_type type)
+{
+	switch (type) {
+	default:
+	case CDP_NONE:
+		return closid;
+	case CDP_CODE:
+		return closid * 2 + 1;
+	case CDP_DATA:
+		return closid * 2;
+	}
+}
+
+static bool apply_config(struct rdt_hw_domain *hw_dom,
+			 struct resctrl_staged_config *cfg, u32 idx,
+			 cpumask_var_t cpu_mask)
+{
+	struct rdt_domain *dom = &hw_dom->d_resctrl;
+
+	if (cfg->new_ctrl != hw_dom->ctrl_val[idx]) {
+		cpumask_set_cpu(cpumask_any(&dom->cpu_mask), cpu_mask);
+		hw_dom->ctrl_val[idx] = cfg->new_ctrl;
+
+		return true;
+	}
+
+	return false;
+}
+
+int resctrl_arch_update_one(struct rdt_resource *r, struct rdt_domain *d,
+			    u32 closid, enum resctrl_conf_type t, u32 cfg_val)
+{
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+	struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);
+	u32 idx = get_config_index(closid, t);
+	struct msr_param msr_param;
+
+	if (!cpumask_test_cpu(smp_processor_id(), &d->cpu_mask))
+		return -EINVAL;
+
+	hw_dom->ctrl_val[idx] = cfg_val;
+
+	msr_param.res = r;
+	msr_param.low = idx;
+	msr_param.high = idx + 1;
+	hw_res->msr_update(d, &msr_param, r);
+
+	return 0;
+}
+
+int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid)
+{
+	struct resctrl_staged_config *cfg;
+	struct rdt_hw_domain *hw_dom;
+	struct msr_param msr_param;
+	enum resctrl_conf_type t;
+	cpumask_var_t cpu_mask;
+	struct rdt_domain *d;
+	u32 idx;
+
+	if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))
+		return -ENOMEM;
+
+	msr_param.res = NULL;
+	list_for_each_entry(d, &r->domains, list) {
+		hw_dom = resctrl_to_arch_dom(d);
+		for (t = 0; t < CDP_NUM_TYPES; t++) {
+			cfg = &hw_dom->d_resctrl.staged_config[t];
+			if (!cfg->have_new_ctrl)
+				continue;
+
+			idx = get_config_index(closid, t);
+			if (!apply_config(hw_dom, cfg, idx, cpu_mask))
+				continue;
+
+			if (!msr_param.res) {
+				msr_param.low = idx;
+				msr_param.high = msr_param.low + 1;
+				msr_param.res = r;
+			} else {
+				msr_param.low = min(msr_param.low, idx);
+				msr_param.high = max(msr_param.high, idx + 1);
+			}
+		}
+	}
+
+	if (cpumask_empty(cpu_mask))
+		goto done;
+
+	/* Update resource control msr on all the CPUs. */
+	on_each_cpu_mask(cpu_mask, rdt_ctrl_update, &msr_param, 1);
+
+done:
+	free_cpumask_var(cpu_mask);
+
+	return 0;
+}
+
+static int rdtgroup_parse_resource(char *resname, char *tok,
+				   struct rdtgroup *rdtgrp)
+{
+	struct resctrl_schema *s;
+
+	list_for_each_entry(s, &resctrl_schema_all, list) {
+		if (!strcmp(resname, s->name) && rdtgrp->closid < s->num_closid)
+			return parse_line(tok, s, rdtgrp);
+	}
+	rdt_last_cmd_printf("Unknown or unsupported resource name '%s'\n", resname);
+	return -EINVAL;
+}
+
+ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
+				char *buf, size_t nbytes, loff_t off)
+{
+	struct resctrl_schema *s;
+	struct rdtgroup *rdtgrp;
+	struct rdt_resource *r;
+	char *tok, *resname;
+	int ret = 0;
+
+	/* Valid input requires a trailing newline */
+	if (nbytes == 0 || buf[nbytes - 1] != '\n')
+		return -EINVAL;
+	buf[nbytes - 1] = '\0';
+
+	cpus_read_lock();
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (!rdtgrp) {
+		rdtgroup_kn_unlock(of->kn);
+		cpus_read_unlock();
+		return -ENOENT;
+	}
+	rdt_last_cmd_clear();
+
+	/*
+	 * No changes to pseudo-locked region allowed. It has to be removed
+	 * and re-created instead.
+	 */
+	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) {
+		ret = -EINVAL;
+		rdt_last_cmd_puts("Resource group is pseudo-locked\n");
+		goto out;
+	}
+
+	rdt_staged_configs_clear();
+
+	while ((tok = strsep(&buf, "\n")) != NULL) {
+		resname = strim(strsep(&tok, ":"));
+		if (!tok) {
+			rdt_last_cmd_puts("Missing ':'\n");
+			ret = -EINVAL;
+			goto out;
+		}
+		if (tok[0] == '\0') {
+			rdt_last_cmd_printf("Missing '%s' value\n", resname);
+			ret = -EINVAL;
+			goto out;
+		}
+		ret = rdtgroup_parse_resource(resname, tok, rdtgrp);
+		if (ret)
+			goto out;
+	}
+
+	list_for_each_entry(s, &resctrl_schema_all, list) {
+		r = s->res;
+
+		/*
+		 * Writes to mba_sc resources update the software controller,
+		 * not the control MSR.
+		 */
+		if (is_mba_sc(r))
+			continue;
+
+		ret = resctrl_arch_update_domains(r, rdtgrp->closid);
+		if (ret)
+			goto out;
+	}
+
+	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
+		/*
+		 * If pseudo-locking fails we keep the resource group in
+		 * mode RDT_MODE_PSEUDO_LOCKSETUP with its class of service
+		 * active and updated for just the domain the pseudo-locked
+		 * region was requested for.
+		 */
+		ret = rdtgroup_pseudo_lock_create(rdtgrp);
+	}
+
+out:
+	rdt_staged_configs_clear();
+	rdtgroup_kn_unlock(of->kn);
+	cpus_read_unlock();
+	return ret ?: nbytes;
+}
+
+u32 resctrl_arch_get_config(struct rdt_resource *r, struct rdt_domain *d,
+			    u32 closid, enum resctrl_conf_type type)
+{
+	struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);
+	u32 idx = get_config_index(closid, type);
+
+	return hw_dom->ctrl_val[idx];
+}
+
+static void show_doms(struct seq_file *s, struct resctrl_schema *schema, int closid)
+{
+	struct rdt_resource *r = schema->res;
+	struct rdt_domain *dom;
+	bool sep = false;
+	u32 ctrl_val;
+
+	seq_printf(s, "%*s:", max_name_width, schema->name);
+	list_for_each_entry(dom, &r->domains, list) {
+		if (sep)
+			seq_puts(s, ";");
+
+		if (is_mba_sc(r))
+			ctrl_val = dom->mbps_val[closid];
+		else
+			ctrl_val = resctrl_arch_get_config(r, dom, closid,
+							   schema->conf_type);
+
+		seq_printf(s, r->format_str, dom->id, max_data_width,
+			   ctrl_val);
+		sep = true;
+	}
+	seq_puts(s, "\n");
+}
+
+int rdtgroup_schemata_show(struct kernfs_open_file *of,
+			   struct seq_file *s, void *v)
+{
+	struct resctrl_schema *schema;
+	struct rdtgroup *rdtgrp;
+	int ret = 0;
+	u32 closid;
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (rdtgrp) {
+		if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
+			list_for_each_entry(schema, &resctrl_schema_all, list) {
+				seq_printf(s, "%s:uninitialized\n", schema->name);
+			}
+		} else if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) {
+			if (!rdtgrp->plr->d) {
+				rdt_last_cmd_clear();
+				rdt_last_cmd_puts("Cache domain offline\n");
+				ret = -ENODEV;
+			} else {
+				seq_printf(s, "%s:%d=%x\n",
+					   rdtgrp->plr->s->res->name,
+					   rdtgrp->plr->d->id,
+					   rdtgrp->plr->cbm);
+			}
+		} else {
+			closid = rdtgrp->closid;
+			list_for_each_entry(schema, &resctrl_schema_all, list) {
+				if (closid < schema->num_closid)
+					show_doms(s, schema, closid);
+			}
+		}
+	} else {
+		ret = -ENOENT;
+	}
+	rdtgroup_kn_unlock(of->kn);
+	return ret;
+}
+
+void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
+		    struct rdt_domain *d, struct rdtgroup *rdtgrp,
+		    int evtid, int first)
+{
+	/*
+	 * setup the parameters to send to the IPI to read the data.
+	 */
+	rr->rgrp = rdtgrp;
+	rr->evtid = evtid;
+	rr->r = r;
+	rr->d = d;
+	rr->val = 0;
+	rr->first = first;
+
+	smp_call_function_any(&d->cpu_mask, mon_event_count, rr, 1);
+}
+
+int rdtgroup_mondata_show(struct seq_file *m, void *arg)
+{
+	struct kernfs_open_file *of = m->private;
+	u32 resid, evtid, domid;
+	struct rdtgroup *rdtgrp;
+	struct rdt_resource *r;
+	union mon_data_bits md;
+	struct rdt_domain *d;
+	struct rmid_read rr;
+	int ret = 0;
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (!rdtgrp) {
+		ret = -ENOENT;
+		goto out;
+	}
+
+	md.priv = of->kn->priv;
+	resid = md.u.rid;
+	domid = md.u.domid;
+	evtid = md.u.evtid;
+
+	r = &rdt_resources_all[resid].r_resctrl;
+	d = rdt_find_domain(r, domid, NULL);
+	if (IS_ERR_OR_NULL(d)) {
+		ret = -ENOENT;
+		goto out;
+	}
+
+	mon_event_read(&rr, r, d, rdtgrp, evtid, false);
+
+	if (rr.err == -EIO)
+		seq_puts(m, "Error\n");
+	else if (rr.err == -EINVAL)
+		seq_puts(m, "Unavailable\n");
+	else
+		seq_printf(m, "%llu\n", rr.val);
+
+out:
+	rdtgroup_kn_unlock(of->kn);
+	return ret;
+}
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
new file mode 100644
index 0000000000..85ceaf9a31
--- /dev/null
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -0,0 +1,560 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_RESCTRL_INTERNAL_H
+#define _ASM_X86_RESCTRL_INTERNAL_H
+
+#include <linux/resctrl.h>
+#include <linux/sched.h>
+#include <linux/kernfs.h>
+#include <linux/fs_context.h>
+#include <linux/jump_label.h>
+
+#define L3_QOS_CDP_ENABLE		0x01ULL
+
+#define L2_QOS_CDP_ENABLE		0x01ULL
+
+#define CQM_LIMBOCHECK_INTERVAL	1000
+
+#define MBM_CNTR_WIDTH_BASE		24
+#define MBM_OVERFLOW_INTERVAL		1000
+#define MAX_MBA_BW			100u
+#define MBA_IS_LINEAR			0x4
+#define MAX_MBA_BW_AMD			0x800
+#define MBM_CNTR_WIDTH_OFFSET_AMD	20
+
+#define RMID_VAL_ERROR			BIT_ULL(63)
+#define RMID_VAL_UNAVAIL		BIT_ULL(62)
+/*
+ * With the above fields in use 62 bits remain in MSR_IA32_QM_CTR for
+ * data to be returned. The counter width is discovered from the hardware
+ * as an offset from MBM_CNTR_WIDTH_BASE.
+ */
+#define MBM_CNTR_WIDTH_OFFSET_MAX (62 - MBM_CNTR_WIDTH_BASE)
+
+/* Reads to Local DRAM Memory */
+#define READS_TO_LOCAL_MEM		BIT(0)
+
+/* Reads to Remote DRAM Memory */
+#define READS_TO_REMOTE_MEM		BIT(1)
+
+/* Non-Temporal Writes to Local Memory */
+#define NON_TEMP_WRITE_TO_LOCAL_MEM	BIT(2)
+
+/* Non-Temporal Writes to Remote Memory */
+#define NON_TEMP_WRITE_TO_REMOTE_MEM	BIT(3)
+
+/* Reads to Local Memory the system identifies as "Slow Memory" */
+#define READS_TO_LOCAL_S_MEM		BIT(4)
+
+/* Reads to Remote Memory the system identifies as "Slow Memory" */
+#define READS_TO_REMOTE_S_MEM		BIT(5)
+
+/* Dirty Victims to All Types of Memory */
+#define DIRTY_VICTIMS_TO_ALL_MEM	BIT(6)
+
+/* Max event bits supported */
+#define MAX_EVT_CONFIG_BITS		GENMASK(6, 0)
+
+struct rdt_fs_context {
+	struct kernfs_fs_context	kfc;
+	bool				enable_cdpl2;
+	bool				enable_cdpl3;
+	bool				enable_mba_mbps;
+};
+
+static inline struct rdt_fs_context *rdt_fc2context(struct fs_context *fc)
+{
+	struct kernfs_fs_context *kfc = fc->fs_private;
+
+	return container_of(kfc, struct rdt_fs_context, kfc);
+}
+
+DECLARE_STATIC_KEY_FALSE(rdt_enable_key);
+DECLARE_STATIC_KEY_FALSE(rdt_mon_enable_key);
+
+/**
+ * struct mon_evt - Entry in the event list of a resource
+ * @evtid:		event id
+ * @name:		name of the event
+ * @configurable:	true if the event is configurable
+ * @list:		entry in &rdt_resource->evt_list
+ */
+struct mon_evt {
+	enum resctrl_event_id	evtid;
+	char			*name;
+	bool			configurable;
+	struct list_head	list;
+};
+
+/**
+ * union mon_data_bits - Monitoring details for each event file
+ * @priv:              Used to store monitoring event data in @u
+ *                     as kernfs private data
+ * @rid:               Resource id associated with the event file
+ * @evtid:             Event id associated with the event file
+ * @domid:             The domain to which the event file belongs
+ * @u:                 Name of the bit fields struct
+ */
+union mon_data_bits {
+	void *priv;
+	struct {
+		unsigned int rid		: 10;
+		enum resctrl_event_id evtid	: 8;
+		unsigned int domid		: 14;
+	} u;
+};
+
+struct rmid_read {
+	struct rdtgroup		*rgrp;
+	struct rdt_resource	*r;
+	struct rdt_domain	*d;
+	enum resctrl_event_id	evtid;
+	bool			first;
+	int			err;
+	u64			val;
+};
+
+extern bool rdt_alloc_capable;
+extern bool rdt_mon_capable;
+extern unsigned int rdt_mon_features;
+extern struct list_head resctrl_schema_all;
+
+enum rdt_group_type {
+	RDTCTRL_GROUP = 0,
+	RDTMON_GROUP,
+	RDT_NUM_GROUP,
+};
+
+/**
+ * enum rdtgrp_mode - Mode of a RDT resource group
+ * @RDT_MODE_SHAREABLE: This resource group allows sharing of its allocations
+ * @RDT_MODE_EXCLUSIVE: No sharing of this resource group's allocations allowed
+ * @RDT_MODE_PSEUDO_LOCKSETUP: Resource group will be used for Pseudo-Locking
+ * @RDT_MODE_PSEUDO_LOCKED: No sharing of this resource group's allocations
+ *                          allowed AND the allocations are Cache Pseudo-Locked
+ * @RDT_NUM_MODES: Total number of modes
+ *
+ * The mode of a resource group enables control over the allowed overlap
+ * between allocations associated with different resource groups (classes
+ * of service). User is able to modify the mode of a resource group by
+ * writing to the "mode" resctrl file associated with the resource group.
+ *
+ * The "shareable", "exclusive", and "pseudo-locksetup" modes are set by
+ * writing the appropriate text to the "mode" file. A resource group enters
+ * "pseudo-locked" mode after the schemata is written while the resource
+ * group is in "pseudo-locksetup" mode.
+ */
+enum rdtgrp_mode {
+	RDT_MODE_SHAREABLE = 0,
+	RDT_MODE_EXCLUSIVE,
+	RDT_MODE_PSEUDO_LOCKSETUP,
+	RDT_MODE_PSEUDO_LOCKED,
+
+	/* Must be last */
+	RDT_NUM_MODES,
+};
+
+/**
+ * struct mongroup - store mon group's data in resctrl fs.
+ * @mon_data_kn:		kernfs node for the mon_data directory
+ * @parent:			parent rdtgrp
+ * @crdtgrp_list:		child rdtgroup node list
+ * @rmid:			rmid for this rdtgroup
+ */
+struct mongroup {
+	struct kernfs_node	*mon_data_kn;
+	struct rdtgroup		*parent;
+	struct list_head	crdtgrp_list;
+	u32			rmid;
+};
+
+/**
+ * struct pseudo_lock_region - pseudo-lock region information
+ * @s:			Resctrl schema for the resource to which this
+ *			pseudo-locked region belongs
+ * @d:			RDT domain to which this pseudo-locked region
+ *			belongs
+ * @cbm:		bitmask of the pseudo-locked region
+ * @lock_thread_wq:	waitqueue used to wait on the pseudo-locking thread
+ *			completion
+ * @thread_done:	variable used by waitqueue to test if pseudo-locking
+ *			thread completed
+ * @cpu:		core associated with the cache on which the setup code
+ *			will be run
+ * @line_size:		size of the cache lines
+ * @size:		size of pseudo-locked region in bytes
+ * @kmem:		the kernel memory associated with pseudo-locked region
+ * @minor:		minor number of character device associated with this
+ *			region
+ * @debugfs_dir:	pointer to this region's directory in the debugfs
+ *			filesystem
+ * @pm_reqs:		Power management QoS requests related to this region
+ */
+struct pseudo_lock_region {
+	struct resctrl_schema	*s;
+	struct rdt_domain	*d;
+	u32			cbm;
+	wait_queue_head_t	lock_thread_wq;
+	int			thread_done;
+	int			cpu;
+	unsigned int		line_size;
+	unsigned int		size;
+	void			*kmem;
+	unsigned int		minor;
+	struct dentry		*debugfs_dir;
+	struct list_head	pm_reqs;
+};
+
+/**
+ * struct rdtgroup - store rdtgroup's data in resctrl file system.
+ * @kn:				kernfs node
+ * @rdtgroup_list:		linked list for all rdtgroups
+ * @closid:			closid for this rdtgroup
+ * @cpu_mask:			CPUs assigned to this rdtgroup
+ * @flags:			status bits
+ * @waitcount:			how many cpus expect to find this
+ *				group when they acquire rdtgroup_mutex
+ * @type:			indicates type of this rdtgroup - either
+ *				monitor only or ctrl_mon group
+ * @mon:			mongroup related data
+ * @mode:			mode of resource group
+ * @plr:			pseudo-locked region
+ */
+struct rdtgroup {
+	struct kernfs_node		*kn;
+	struct list_head		rdtgroup_list;
+	u32				closid;
+	struct cpumask			cpu_mask;
+	int				flags;
+	atomic_t			waitcount;
+	enum rdt_group_type		type;
+	struct mongroup			mon;
+	enum rdtgrp_mode		mode;
+	struct pseudo_lock_region	*plr;
+};
+
+/* rdtgroup.flags */
+#define	RDT_DELETED		1
+
+/* rftype.flags */
+#define RFTYPE_FLAGS_CPUS_LIST	1
+
+/*
+ * Define the file type flags for base and info directories.
+ */
+#define RFTYPE_INFO			BIT(0)
+#define RFTYPE_BASE			BIT(1)
+#define RF_CTRLSHIFT			4
+#define RF_MONSHIFT			5
+#define RF_TOPSHIFT			6
+#define RFTYPE_CTRL			BIT(RF_CTRLSHIFT)
+#define RFTYPE_MON			BIT(RF_MONSHIFT)
+#define RFTYPE_TOP			BIT(RF_TOPSHIFT)
+#define RFTYPE_RES_CACHE		BIT(8)
+#define RFTYPE_RES_MB			BIT(9)
+#define RF_CTRL_INFO			(RFTYPE_INFO | RFTYPE_CTRL)
+#define RF_MON_INFO			(RFTYPE_INFO | RFTYPE_MON)
+#define RF_TOP_INFO			(RFTYPE_INFO | RFTYPE_TOP)
+#define RF_CTRL_BASE			(RFTYPE_BASE | RFTYPE_CTRL)
+
+/* List of all resource groups */
+extern struct list_head rdt_all_groups;
+
+extern int max_name_width, max_data_width;
+
+int __init rdtgroup_init(void);
+void __exit rdtgroup_exit(void);
+
+/**
+ * struct rftype - describe each file in the resctrl file system
+ * @name:	File name
+ * @mode:	Access mode
+ * @kf_ops:	File operations
+ * @flags:	File specific RFTYPE_FLAGS_* flags
+ * @fflags:	File specific RF_* or RFTYPE_* flags
+ * @seq_show:	Show content of the file
+ * @write:	Write to the file
+ */
+struct rftype {
+	char			*name;
+	umode_t			mode;
+	const struct kernfs_ops	*kf_ops;
+	unsigned long		flags;
+	unsigned long		fflags;
+
+	int (*seq_show)(struct kernfs_open_file *of,
+			struct seq_file *sf, void *v);
+	/*
+	 * write() is the generic write callback which maps directly to
+	 * kernfs write operation and overrides all other operations.
+	 * Maximum write size is determined by ->max_write_len.
+	 */
+	ssize_t (*write)(struct kernfs_open_file *of,
+			 char *buf, size_t nbytes, loff_t off);
+};
+
+/**
+ * struct mbm_state - status for each MBM counter in each domain
+ * @prev_bw_bytes: Previous bytes value read for bandwidth calculation
+ * @prev_bw:	The most recent bandwidth in MBps
+ * @delta_bw:	Difference between the current and previous bandwidth
+ * @delta_comp:	Indicates whether to compute the delta_bw
+ */
+struct mbm_state {
+	u64	prev_bw_bytes;
+	u32	prev_bw;
+	u32	delta_bw;
+	bool	delta_comp;
+};
+
+/**
+ * struct arch_mbm_state - values used to compute resctrl_arch_rmid_read()s
+ *			   return value.
+ * @chunks:	Total data moved (multiply by rdt_group.mon_scale to get bytes)
+ * @prev_msr:	Value of IA32_QM_CTR last time it was read for the RMID used to
+ *		find this struct.
+ */
+struct arch_mbm_state {
+	u64	chunks;
+	u64	prev_msr;
+};
+
+/**
+ * struct rdt_hw_domain - Arch private attributes of a set of CPUs that share
+ *			  a resource
+ * @d_resctrl:	Properties exposed to the resctrl file system
+ * @ctrl_val:	array of cache or mem ctrl values (indexed by CLOSID)
+ * @arch_mbm_total:	arch private state for MBM total bandwidth
+ * @arch_mbm_local:	arch private state for MBM local bandwidth
+ *
+ * Members of this structure are accessed via helpers that provide abstraction.
+ */
+struct rdt_hw_domain {
+	struct rdt_domain		d_resctrl;
+	u32				*ctrl_val;
+	struct arch_mbm_state		*arch_mbm_total;
+	struct arch_mbm_state		*arch_mbm_local;
+};
+
+static inline struct rdt_hw_domain *resctrl_to_arch_dom(struct rdt_domain *r)
+{
+	return container_of(r, struct rdt_hw_domain, d_resctrl);
+}
+
+/**
+ * struct msr_param - set a range of MSRs from a domain
+ * @res:       The resource to use
+ * @low:       Beginning index from base MSR
+ * @high:      End index
+ */
+struct msr_param {
+	struct rdt_resource	*res;
+	u32			low;
+	u32			high;
+};
+
+static inline bool is_llc_occupancy_enabled(void)
+{
+	return (rdt_mon_features & (1 << QOS_L3_OCCUP_EVENT_ID));
+}
+
+static inline bool is_mbm_total_enabled(void)
+{
+	return (rdt_mon_features & (1 << QOS_L3_MBM_TOTAL_EVENT_ID));
+}
+
+static inline bool is_mbm_local_enabled(void)
+{
+	return (rdt_mon_features & (1 << QOS_L3_MBM_LOCAL_EVENT_ID));
+}
+
+static inline bool is_mbm_enabled(void)
+{
+	return (is_mbm_total_enabled() || is_mbm_local_enabled());
+}
+
+static inline bool is_mbm_event(int e)
+{
+	return (e >= QOS_L3_MBM_TOTAL_EVENT_ID &&
+		e <= QOS_L3_MBM_LOCAL_EVENT_ID);
+}
+
+struct rdt_parse_data {
+	struct rdtgroup		*rdtgrp;
+	char			*buf;
+};
+
+/**
+ * struct rdt_hw_resource - arch private attributes of a resctrl resource
+ * @r_resctrl:		Attributes of the resource used directly by resctrl.
+ * @num_closid:		Maximum number of closid this hardware can support,
+ *			regardless of CDP. This is exposed via
+ *			resctrl_arch_get_num_closid() to avoid confusion
+ *			with struct resctrl_schema's property of the same name,
+ *			which has been corrected for features like CDP.
+ * @msr_base:		Base MSR address for CBMs
+ * @msr_update:		Function pointer to update QOS MSRs
+ * @mon_scale:		cqm counter * mon_scale = occupancy in bytes
+ * @mbm_width:		Monitor width, to detect and correct for overflow.
+ * @cdp_enabled:	CDP state of this resource
+ *
+ * Members of this structure are either private to the architecture
+ * e.g. mbm_width, or accessed via helpers that provide abstraction. e.g.
+ * msr_update and msr_base.
+ */
+struct rdt_hw_resource {
+	struct rdt_resource	r_resctrl;
+	u32			num_closid;
+	unsigned int		msr_base;
+	void (*msr_update)	(struct rdt_domain *d, struct msr_param *m,
+				 struct rdt_resource *r);
+	unsigned int		mon_scale;
+	unsigned int		mbm_width;
+	bool			cdp_enabled;
+};
+
+static inline struct rdt_hw_resource *resctrl_to_arch_res(struct rdt_resource *r)
+{
+	return container_of(r, struct rdt_hw_resource, r_resctrl);
+}
+
+int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
+	      struct rdt_domain *d);
+int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s,
+	     struct rdt_domain *d);
+
+extern struct mutex rdtgroup_mutex;
+
+extern struct rdt_hw_resource rdt_resources_all[];
+extern struct rdtgroup rdtgroup_default;
+DECLARE_STATIC_KEY_FALSE(rdt_alloc_enable_key);
+
+extern struct dentry *debugfs_resctrl;
+
+enum resctrl_res_level {
+	RDT_RESOURCE_L3,
+	RDT_RESOURCE_L2,
+	RDT_RESOURCE_MBA,
+	RDT_RESOURCE_SMBA,
+
+	/* Must be the last */
+	RDT_NUM_RESOURCES,
+};
+
+static inline struct rdt_resource *resctrl_inc(struct rdt_resource *res)
+{
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(res);
+
+	hw_res++;
+	return &hw_res->r_resctrl;
+}
+
+static inline bool resctrl_arch_get_cdp_enabled(enum resctrl_res_level l)
+{
+	return rdt_resources_all[l].cdp_enabled;
+}
+
+int resctrl_arch_set_cdp_enabled(enum resctrl_res_level l, bool enable);
+
+/*
+ * To return the common struct rdt_resource, which is contained in struct
+ * rdt_hw_resource, walk the resctrl member of struct rdt_hw_resource.
+ */
+#define for_each_rdt_resource(r)					      \
+	for (r = &rdt_resources_all[0].r_resctrl;			      \
+	     r <= &rdt_resources_all[RDT_NUM_RESOURCES - 1].r_resctrl;	      \
+	     r = resctrl_inc(r))
+
+#define for_each_capable_rdt_resource(r)				      \
+	for_each_rdt_resource(r)					      \
+		if (r->alloc_capable || r->mon_capable)
+
+#define for_each_alloc_capable_rdt_resource(r)				      \
+	for_each_rdt_resource(r)					      \
+		if (r->alloc_capable)
+
+#define for_each_mon_capable_rdt_resource(r)				      \
+	for_each_rdt_resource(r)					      \
+		if (r->mon_capable)
+
+/* CPUID.(EAX=10H, ECX=ResID=1).EAX */
+union cpuid_0x10_1_eax {
+	struct {
+		unsigned int cbm_len:5;
+	} split;
+	unsigned int full;
+};
+
+/* CPUID.(EAX=10H, ECX=ResID=3).EAX */
+union cpuid_0x10_3_eax {
+	struct {
+		unsigned int max_delay:12;
+	} split;
+	unsigned int full;
+};
+
+/* CPUID.(EAX=10H, ECX=ResID).EDX */
+union cpuid_0x10_x_edx {
+	struct {
+		unsigned int cos_max:16;
+	} split;
+	unsigned int full;
+};
+
+void rdt_last_cmd_clear(void);
+void rdt_last_cmd_puts(const char *s);
+__printf(1, 2)
+void rdt_last_cmd_printf(const char *fmt, ...);
+
+void rdt_ctrl_update(void *arg);
+struct rdtgroup *rdtgroup_kn_lock_live(struct kernfs_node *kn);
+void rdtgroup_kn_unlock(struct kernfs_node *kn);
+int rdtgroup_kn_mode_restrict(struct rdtgroup *r, const char *name);
+int rdtgroup_kn_mode_restore(struct rdtgroup *r, const char *name,
+			     umode_t mask);
+struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id,
+				   struct list_head **pos);
+ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
+				char *buf, size_t nbytes, loff_t off);
+int rdtgroup_schemata_show(struct kernfs_open_file *of,
+			   struct seq_file *s, void *v);
+bool rdtgroup_cbm_overlaps(struct resctrl_schema *s, struct rdt_domain *d,
+			   unsigned long cbm, int closid, bool exclusive);
+unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r, struct rdt_domain *d,
+				  unsigned long cbm);
+enum rdtgrp_mode rdtgroup_mode_by_closid(int closid);
+int rdtgroup_tasks_assigned(struct rdtgroup *r);
+int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp);
+int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp);
+bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_domain *d, unsigned long cbm);
+bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_domain *d);
+int rdt_pseudo_lock_init(void);
+void rdt_pseudo_lock_release(void);
+int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp);
+void rdtgroup_pseudo_lock_remove(struct rdtgroup *rdtgrp);
+struct rdt_domain *get_domain_from_cpu(int cpu, struct rdt_resource *r);
+int closids_supported(void);
+void closid_free(int closid);
+int alloc_rmid(void);
+void free_rmid(u32 rmid);
+int rdt_get_mon_l3_config(struct rdt_resource *r);
+bool __init rdt_cpu_has(int flag);
+void mon_event_count(void *info);
+int rdtgroup_mondata_show(struct seq_file *m, void *arg);
+void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
+		    struct rdt_domain *d, struct rdtgroup *rdtgrp,
+		    int evtid, int first);
+void mbm_setup_overflow_handler(struct rdt_domain *dom,
+				unsigned long delay_ms);
+void mbm_handle_overflow(struct work_struct *work);
+void __init intel_rdt_mbm_apply_quirk(void);
+bool is_mba_sc(struct rdt_resource *r);
+void cqm_setup_limbo_handler(struct rdt_domain *dom, unsigned long delay_ms);
+void cqm_handle_limbo(struct work_struct *work);
+bool has_busy_rmid(struct rdt_resource *r, struct rdt_domain *d);
+void __check_limbo(struct rdt_domain *d, bool force_free);
+void rdt_domain_reconfigure_cdp(struct rdt_resource *r);
+void __init thread_throttle_mode_init(void);
+void __init mbm_config_rftype_init(const char *config);
+void rdt_staged_configs_clear(void);
+
+#endif /* _ASM_X86_RESCTRL_INTERNAL_H */
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
new file mode 100644
index 0000000000..f136ac0468
--- /dev/null
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -0,0 +1,845 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Resource Director Technology(RDT)
+ * - Monitoring code
+ *
+ * Copyright (C) 2017 Intel Corporation
+ *
+ * Author:
+ *    Vikas Shivappa <vikas.shivappa@intel.com>
+ *
+ * This replaces the cqm.c based on perf but we reuse a lot of
+ * code and datastructures originally from Peter Zijlstra and Matt Fleming.
+ *
+ * More information about RDT be found in the Intel (R) x86 Architecture
+ * Software Developer Manual June 2016, volume 3, section 17.17.
+ */
+
+#include <linux/module.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+
+#include <asm/cpu_device_id.h>
+#include <asm/resctrl.h>
+
+#include "internal.h"
+
+struct rmid_entry {
+	u32				rmid;
+	int				busy;
+	struct list_head		list;
+};
+
+/*
+ * @rmid_free_lru - A least recently used list of free RMIDs
+ *     These RMIDs are guaranteed to have an occupancy less than the
+ *     threshold occupancy
+ */
+static LIST_HEAD(rmid_free_lru);
+
+/*
+ * @rmid_limbo_count - count of currently unused but (potentially)
+ *     dirty RMIDs.
+ *     This counts RMIDs that no one is currently using but that
+ *     may have a occupancy value > resctrl_rmid_realloc_threshold. User can
+ *     change the threshold occupancy value.
+ */
+static unsigned int rmid_limbo_count;
+
+/*
+ * @rmid_entry - The entry in the limbo and free lists.
+ */
+static struct rmid_entry	*rmid_ptrs;
+
+/*
+ * Global boolean for rdt_monitor which is true if any
+ * resource monitoring is enabled.
+ */
+bool rdt_mon_capable;
+
+/*
+ * Global to indicate which monitoring events are enabled.
+ */
+unsigned int rdt_mon_features;
+
+/*
+ * This is the threshold cache occupancy in bytes at which we will consider an
+ * RMID available for re-allocation.
+ */
+unsigned int resctrl_rmid_realloc_threshold;
+
+/*
+ * This is the maximum value for the reallocation threshold, in bytes.
+ */
+unsigned int resctrl_rmid_realloc_limit;
+
+#define CF(cf)	((unsigned long)(1048576 * (cf) + 0.5))
+
+/*
+ * The correction factor table is documented in Documentation/arch/x86/resctrl.rst.
+ * If rmid > rmid threshold, MBM total and local values should be multiplied
+ * by the correction factor.
+ *
+ * The original table is modified for better code:
+ *
+ * 1. The threshold 0 is changed to rmid count - 1 so don't do correction
+ *    for the case.
+ * 2. MBM total and local correction table indexed by core counter which is
+ *    equal to (x86_cache_max_rmid + 1) / 8 - 1 and is from 0 up to 27.
+ * 3. The correction factor is normalized to 2^20 (1048576) so it's faster
+ *    to calculate corrected value by shifting:
+ *    corrected_value = (original_value * correction_factor) >> 20
+ */
+static const struct mbm_correction_factor_table {
+	u32 rmidthreshold;
+	u64 cf;
+} mbm_cf_table[] __initconst = {
+	{7,	CF(1.000000)},
+	{15,	CF(1.000000)},
+	{15,	CF(0.969650)},
+	{31,	CF(1.000000)},
+	{31,	CF(1.066667)},
+	{31,	CF(0.969650)},
+	{47,	CF(1.142857)},
+	{63,	CF(1.000000)},
+	{63,	CF(1.185115)},
+	{63,	CF(1.066553)},
+	{79,	CF(1.454545)},
+	{95,	CF(1.000000)},
+	{95,	CF(1.230769)},
+	{95,	CF(1.142857)},
+	{95,	CF(1.066667)},
+	{127,	CF(1.000000)},
+	{127,	CF(1.254863)},
+	{127,	CF(1.185255)},
+	{151,	CF(1.000000)},
+	{127,	CF(1.066667)},
+	{167,	CF(1.000000)},
+	{159,	CF(1.454334)},
+	{183,	CF(1.000000)},
+	{127,	CF(0.969744)},
+	{191,	CF(1.280246)},
+	{191,	CF(1.230921)},
+	{215,	CF(1.000000)},
+	{191,	CF(1.143118)},
+};
+
+static u32 mbm_cf_rmidthreshold __read_mostly = UINT_MAX;
+static u64 mbm_cf __read_mostly;
+
+static inline u64 get_corrected_mbm_count(u32 rmid, unsigned long val)
+{
+	/* Correct MBM value. */
+	if (rmid > mbm_cf_rmidthreshold)
+		val = (val * mbm_cf) >> 20;
+
+	return val;
+}
+
+static inline struct rmid_entry *__rmid_entry(u32 rmid)
+{
+	struct rmid_entry *entry;
+
+	entry = &rmid_ptrs[rmid];
+	WARN_ON(entry->rmid != rmid);
+
+	return entry;
+}
+
+static int __rmid_read(u32 rmid, enum resctrl_event_id eventid, u64 *val)
+{
+	u64 msr_val;
+
+	/*
+	 * As per the SDM, when IA32_QM_EVTSEL.EvtID (bits 7:0) is configured
+	 * with a valid event code for supported resource type and the bits
+	 * IA32_QM_EVTSEL.RMID (bits 41:32) are configured with valid RMID,
+	 * IA32_QM_CTR.data (bits 61:0) reports the monitored data.
+	 * IA32_QM_CTR.Error (bit 63) and IA32_QM_CTR.Unavailable (bit 62)
+	 * are error bits.
+	 */
+	wrmsr(MSR_IA32_QM_EVTSEL, eventid, rmid);
+	rdmsrl(MSR_IA32_QM_CTR, msr_val);
+
+	if (msr_val & RMID_VAL_ERROR)
+		return -EIO;
+	if (msr_val & RMID_VAL_UNAVAIL)
+		return -EINVAL;
+
+	*val = msr_val;
+	return 0;
+}
+
+static struct arch_mbm_state *get_arch_mbm_state(struct rdt_hw_domain *hw_dom,
+						 u32 rmid,
+						 enum resctrl_event_id eventid)
+{
+	switch (eventid) {
+	case QOS_L3_OCCUP_EVENT_ID:
+		return NULL;
+	case QOS_L3_MBM_TOTAL_EVENT_ID:
+		return &hw_dom->arch_mbm_total[rmid];
+	case QOS_L3_MBM_LOCAL_EVENT_ID:
+		return &hw_dom->arch_mbm_local[rmid];
+	}
+
+	/* Never expect to get here */
+	WARN_ON_ONCE(1);
+
+	return NULL;
+}
+
+void resctrl_arch_reset_rmid(struct rdt_resource *r, struct rdt_domain *d,
+			     u32 rmid, enum resctrl_event_id eventid)
+{
+	struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);
+	struct arch_mbm_state *am;
+
+	am = get_arch_mbm_state(hw_dom, rmid, eventid);
+	if (am) {
+		memset(am, 0, sizeof(*am));
+
+		/* Record any initial, non-zero count value. */
+		__rmid_read(rmid, eventid, &am->prev_msr);
+	}
+}
+
+/*
+ * Assumes that hardware counters are also reset and thus that there is
+ * no need to record initial non-zero counts.
+ */
+void resctrl_arch_reset_rmid_all(struct rdt_resource *r, struct rdt_domain *d)
+{
+	struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);
+
+	if (is_mbm_total_enabled())
+		memset(hw_dom->arch_mbm_total, 0,
+		       sizeof(*hw_dom->arch_mbm_total) * r->num_rmid);
+
+	if (is_mbm_local_enabled())
+		memset(hw_dom->arch_mbm_local, 0,
+		       sizeof(*hw_dom->arch_mbm_local) * r->num_rmid);
+}
+
+static u64 mbm_overflow_count(u64 prev_msr, u64 cur_msr, unsigned int width)
+{
+	u64 shift = 64 - width, chunks;
+
+	chunks = (cur_msr << shift) - (prev_msr << shift);
+	return chunks >> shift;
+}
+
+int resctrl_arch_rmid_read(struct rdt_resource *r, struct rdt_domain *d,
+			   u32 rmid, enum resctrl_event_id eventid, u64 *val)
+{
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+	struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);
+	struct arch_mbm_state *am;
+	u64 msr_val, chunks;
+	int ret;
+
+	if (!cpumask_test_cpu(smp_processor_id(), &d->cpu_mask))
+		return -EINVAL;
+
+	ret = __rmid_read(rmid, eventid, &msr_val);
+	if (ret)
+		return ret;
+
+	am = get_arch_mbm_state(hw_dom, rmid, eventid);
+	if (am) {
+		am->chunks += mbm_overflow_count(am->prev_msr, msr_val,
+						 hw_res->mbm_width);
+		chunks = get_corrected_mbm_count(rmid, am->chunks);
+		am->prev_msr = msr_val;
+	} else {
+		chunks = msr_val;
+	}
+
+	*val = chunks * hw_res->mon_scale;
+
+	return 0;
+}
+
+/*
+ * Check the RMIDs that are marked as busy for this domain. If the
+ * reported LLC occupancy is below the threshold clear the busy bit and
+ * decrement the count. If the busy count gets to zero on an RMID, we
+ * free the RMID
+ */
+void __check_limbo(struct rdt_domain *d, bool force_free)
+{
+	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	struct rmid_entry *entry;
+	u32 crmid = 1, nrmid;
+	bool rmid_dirty;
+	u64 val = 0;
+
+	/*
+	 * Skip RMID 0 and start from RMID 1 and check all the RMIDs that
+	 * are marked as busy for occupancy < threshold. If the occupancy
+	 * is less than the threshold decrement the busy counter of the
+	 * RMID and move it to the free list when the counter reaches 0.
+	 */
+	for (;;) {
+		nrmid = find_next_bit(d->rmid_busy_llc, r->num_rmid, crmid);
+		if (nrmid >= r->num_rmid)
+			break;
+
+		entry = __rmid_entry(nrmid);
+
+		if (resctrl_arch_rmid_read(r, d, entry->rmid,
+					   QOS_L3_OCCUP_EVENT_ID, &val)) {
+			rmid_dirty = true;
+		} else {
+			rmid_dirty = (val >= resctrl_rmid_realloc_threshold);
+		}
+
+		if (force_free || !rmid_dirty) {
+			clear_bit(entry->rmid, d->rmid_busy_llc);
+			if (!--entry->busy) {
+				rmid_limbo_count--;
+				list_add_tail(&entry->list, &rmid_free_lru);
+			}
+		}
+		crmid = nrmid + 1;
+	}
+}
+
+bool has_busy_rmid(struct rdt_resource *r, struct rdt_domain *d)
+{
+	return find_first_bit(d->rmid_busy_llc, r->num_rmid) != r->num_rmid;
+}
+
+/*
+ * As of now the RMIDs allocation is global.
+ * However we keep track of which packages the RMIDs
+ * are used to optimize the limbo list management.
+ */
+int alloc_rmid(void)
+{
+	struct rmid_entry *entry;
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	if (list_empty(&rmid_free_lru))
+		return rmid_limbo_count ? -EBUSY : -ENOSPC;
+
+	entry = list_first_entry(&rmid_free_lru,
+				 struct rmid_entry, list);
+	list_del(&entry->list);
+
+	return entry->rmid;
+}
+
+static void add_rmid_to_limbo(struct rmid_entry *entry)
+{
+	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	struct rdt_domain *d;
+	int cpu, err;
+	u64 val = 0;
+
+	entry->busy = 0;
+	cpu = get_cpu();
+	list_for_each_entry(d, &r->domains, list) {
+		if (cpumask_test_cpu(cpu, &d->cpu_mask)) {
+			err = resctrl_arch_rmid_read(r, d, entry->rmid,
+						     QOS_L3_OCCUP_EVENT_ID,
+						     &val);
+			if (err || val <= resctrl_rmid_realloc_threshold)
+				continue;
+		}
+
+		/*
+		 * For the first limbo RMID in the domain,
+		 * setup up the limbo worker.
+		 */
+		if (!has_busy_rmid(r, d))
+			cqm_setup_limbo_handler(d, CQM_LIMBOCHECK_INTERVAL);
+		set_bit(entry->rmid, d->rmid_busy_llc);
+		entry->busy++;
+	}
+	put_cpu();
+
+	if (entry->busy)
+		rmid_limbo_count++;
+	else
+		list_add_tail(&entry->list, &rmid_free_lru);
+}
+
+void free_rmid(u32 rmid)
+{
+	struct rmid_entry *entry;
+
+	if (!rmid)
+		return;
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	entry = __rmid_entry(rmid);
+
+	if (is_llc_occupancy_enabled())
+		add_rmid_to_limbo(entry);
+	else
+		list_add_tail(&entry->list, &rmid_free_lru);
+}
+
+static struct mbm_state *get_mbm_state(struct rdt_domain *d, u32 rmid,
+				       enum resctrl_event_id evtid)
+{
+	switch (evtid) {
+	case QOS_L3_MBM_TOTAL_EVENT_ID:
+		return &d->mbm_total[rmid];
+	case QOS_L3_MBM_LOCAL_EVENT_ID:
+		return &d->mbm_local[rmid];
+	default:
+		return NULL;
+	}
+}
+
+static int __mon_event_count(u32 rmid, struct rmid_read *rr)
+{
+	struct mbm_state *m;
+	u64 tval = 0;
+
+	if (rr->first) {
+		resctrl_arch_reset_rmid(rr->r, rr->d, rmid, rr->evtid);
+		m = get_mbm_state(rr->d, rmid, rr->evtid);
+		if (m)
+			memset(m, 0, sizeof(struct mbm_state));
+		return 0;
+	}
+
+	rr->err = resctrl_arch_rmid_read(rr->r, rr->d, rmid, rr->evtid, &tval);
+	if (rr->err)
+		return rr->err;
+
+	rr->val += tval;
+
+	return 0;
+}
+
+/*
+ * mbm_bw_count() - Update bw count from values previously read by
+ *		    __mon_event_count().
+ * @rmid:	The rmid used to identify the cached mbm_state.
+ * @rr:		The struct rmid_read populated by __mon_event_count().
+ *
+ * Supporting function to calculate the memory bandwidth
+ * and delta bandwidth in MBps. The chunks value previously read by
+ * __mon_event_count() is compared with the chunks value from the previous
+ * invocation. This must be called once per second to maintain values in MBps.
+ */
+static void mbm_bw_count(u32 rmid, struct rmid_read *rr)
+{
+	struct mbm_state *m = &rr->d->mbm_local[rmid];
+	u64 cur_bw, bytes, cur_bytes;
+
+	cur_bytes = rr->val;
+	bytes = cur_bytes - m->prev_bw_bytes;
+	m->prev_bw_bytes = cur_bytes;
+
+	cur_bw = bytes / SZ_1M;
+
+	if (m->delta_comp)
+		m->delta_bw = abs(cur_bw - m->prev_bw);
+	m->delta_comp = false;
+	m->prev_bw = cur_bw;
+}
+
+/*
+ * This is called via IPI to read the CQM/MBM counters
+ * on a domain.
+ */
+void mon_event_count(void *info)
+{
+	struct rdtgroup *rdtgrp, *entry;
+	struct rmid_read *rr = info;
+	struct list_head *head;
+	int ret;
+
+	rdtgrp = rr->rgrp;
+
+	ret = __mon_event_count(rdtgrp->mon.rmid, rr);
+
+	/*
+	 * For Ctrl groups read data from child monitor groups and
+	 * add them together. Count events which are read successfully.
+	 * Discard the rmid_read's reporting errors.
+	 */
+	head = &rdtgrp->mon.crdtgrp_list;
+
+	if (rdtgrp->type == RDTCTRL_GROUP) {
+		list_for_each_entry(entry, head, mon.crdtgrp_list) {
+			if (__mon_event_count(entry->mon.rmid, rr) == 0)
+				ret = 0;
+		}
+	}
+
+	/*
+	 * __mon_event_count() calls for newly created monitor groups may
+	 * report -EINVAL/Unavailable if the monitor hasn't seen any traffic.
+	 * Discard error if any of the monitor event reads succeeded.
+	 */
+	if (ret == 0)
+		rr->err = 0;
+}
+
+/*
+ * Feedback loop for MBA software controller (mba_sc)
+ *
+ * mba_sc is a feedback loop where we periodically read MBM counters and
+ * adjust the bandwidth percentage values via the IA32_MBA_THRTL_MSRs so
+ * that:
+ *
+ *   current bandwidth(cur_bw) < user specified bandwidth(user_bw)
+ *
+ * This uses the MBM counters to measure the bandwidth and MBA throttle
+ * MSRs to control the bandwidth for a particular rdtgrp. It builds on the
+ * fact that resctrl rdtgroups have both monitoring and control.
+ *
+ * The frequency of the checks is 1s and we just tag along the MBM overflow
+ * timer. Having 1s interval makes the calculation of bandwidth simpler.
+ *
+ * Although MBA's goal is to restrict the bandwidth to a maximum, there may
+ * be a need to increase the bandwidth to avoid unnecessarily restricting
+ * the L2 <-> L3 traffic.
+ *
+ * Since MBA controls the L2 external bandwidth where as MBM measures the
+ * L3 external bandwidth the following sequence could lead to such a
+ * situation.
+ *
+ * Consider an rdtgroup which had high L3 <-> memory traffic in initial
+ * phases -> mba_sc kicks in and reduced bandwidth percentage values -> but
+ * after some time rdtgroup has mostly L2 <-> L3 traffic.
+ *
+ * In this case we may restrict the rdtgroup's L2 <-> L3 traffic as its
+ * throttle MSRs already have low percentage values.  To avoid
+ * unnecessarily restricting such rdtgroups, we also increase the bandwidth.
+ */
+static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_domain *dom_mbm)
+{
+	u32 closid, rmid, cur_msr_val, new_msr_val;
+	struct mbm_state *pmbm_data, *cmbm_data;
+	u32 cur_bw, delta_bw, user_bw;
+	struct rdt_resource *r_mba;
+	struct rdt_domain *dom_mba;
+	struct list_head *head;
+	struct rdtgroup *entry;
+
+	if (!is_mbm_local_enabled())
+		return;
+
+	r_mba = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl;
+
+	closid = rgrp->closid;
+	rmid = rgrp->mon.rmid;
+	pmbm_data = &dom_mbm->mbm_local[rmid];
+
+	dom_mba = get_domain_from_cpu(smp_processor_id(), r_mba);
+	if (!dom_mba) {
+		pr_warn_once("Failure to get domain for MBA update\n");
+		return;
+	}
+
+	cur_bw = pmbm_data->prev_bw;
+	user_bw = dom_mba->mbps_val[closid];
+	delta_bw = pmbm_data->delta_bw;
+
+	/* MBA resource doesn't support CDP */
+	cur_msr_val = resctrl_arch_get_config(r_mba, dom_mba, closid, CDP_NONE);
+
+	/*
+	 * For Ctrl groups read data from child monitor groups.
+	 */
+	head = &rgrp->mon.crdtgrp_list;
+	list_for_each_entry(entry, head, mon.crdtgrp_list) {
+		cmbm_data = &dom_mbm->mbm_local[entry->mon.rmid];
+		cur_bw += cmbm_data->prev_bw;
+		delta_bw += cmbm_data->delta_bw;
+	}
+
+	/*
+	 * Scale up/down the bandwidth linearly for the ctrl group.  The
+	 * bandwidth step is the bandwidth granularity specified by the
+	 * hardware.
+	 *
+	 * The delta_bw is used when increasing the bandwidth so that we
+	 * dont alternately increase and decrease the control values
+	 * continuously.
+	 *
+	 * For ex: consider cur_bw = 90MBps, user_bw = 100MBps and if
+	 * bandwidth step is 20MBps(> user_bw - cur_bw), we would keep
+	 * switching between 90 and 110 continuously if we only check
+	 * cur_bw < user_bw.
+	 */
+	if (cur_msr_val > r_mba->membw.min_bw && user_bw < cur_bw) {
+		new_msr_val = cur_msr_val - r_mba->membw.bw_gran;
+	} else if (cur_msr_val < MAX_MBA_BW &&
+		   (user_bw > (cur_bw + delta_bw))) {
+		new_msr_val = cur_msr_val + r_mba->membw.bw_gran;
+	} else {
+		return;
+	}
+
+	resctrl_arch_update_one(r_mba, dom_mba, closid, CDP_NONE, new_msr_val);
+
+	/*
+	 * Delta values are updated dynamically package wise for each
+	 * rdtgrp every time the throttle MSR changes value.
+	 *
+	 * This is because (1)the increase in bandwidth is not perfectly
+	 * linear and only "approximately" linear even when the hardware
+	 * says it is linear.(2)Also since MBA is a core specific
+	 * mechanism, the delta values vary based on number of cores used
+	 * by the rdtgrp.
+	 */
+	pmbm_data->delta_comp = true;
+	list_for_each_entry(entry, head, mon.crdtgrp_list) {
+		cmbm_data = &dom_mbm->mbm_local[entry->mon.rmid];
+		cmbm_data->delta_comp = true;
+	}
+}
+
+static void mbm_update(struct rdt_resource *r, struct rdt_domain *d, int rmid)
+{
+	struct rmid_read rr;
+
+	rr.first = false;
+	rr.r = r;
+	rr.d = d;
+
+	/*
+	 * This is protected from concurrent reads from user
+	 * as both the user and we hold the global mutex.
+	 */
+	if (is_mbm_total_enabled()) {
+		rr.evtid = QOS_L3_MBM_TOTAL_EVENT_ID;
+		rr.val = 0;
+		__mon_event_count(rmid, &rr);
+	}
+	if (is_mbm_local_enabled()) {
+		rr.evtid = QOS_L3_MBM_LOCAL_EVENT_ID;
+		rr.val = 0;
+		__mon_event_count(rmid, &rr);
+
+		/*
+		 * Call the MBA software controller only for the
+		 * control groups and when user has enabled
+		 * the software controller explicitly.
+		 */
+		if (is_mba_sc(NULL))
+			mbm_bw_count(rmid, &rr);
+	}
+}
+
+/*
+ * Handler to scan the limbo list and move the RMIDs
+ * to free list whose occupancy < threshold_occupancy.
+ */
+void cqm_handle_limbo(struct work_struct *work)
+{
+	unsigned long delay = msecs_to_jiffies(CQM_LIMBOCHECK_INTERVAL);
+	int cpu = smp_processor_id();
+	struct rdt_resource *r;
+	struct rdt_domain *d;
+
+	mutex_lock(&rdtgroup_mutex);
+
+	r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	d = container_of(work, struct rdt_domain, cqm_limbo.work);
+
+	__check_limbo(d, false);
+
+	if (has_busy_rmid(r, d))
+		schedule_delayed_work_on(cpu, &d->cqm_limbo, delay);
+
+	mutex_unlock(&rdtgroup_mutex);
+}
+
+void cqm_setup_limbo_handler(struct rdt_domain *dom, unsigned long delay_ms)
+{
+	unsigned long delay = msecs_to_jiffies(delay_ms);
+	int cpu;
+
+	cpu = cpumask_any(&dom->cpu_mask);
+	dom->cqm_work_cpu = cpu;
+
+	schedule_delayed_work_on(cpu, &dom->cqm_limbo, delay);
+}
+
+void mbm_handle_overflow(struct work_struct *work)
+{
+	unsigned long delay = msecs_to_jiffies(MBM_OVERFLOW_INTERVAL);
+	struct rdtgroup *prgrp, *crgrp;
+	int cpu = smp_processor_id();
+	struct list_head *head;
+	struct rdt_resource *r;
+	struct rdt_domain *d;
+
+	mutex_lock(&rdtgroup_mutex);
+
+	if (!static_branch_likely(&rdt_mon_enable_key))
+		goto out_unlock;
+
+	r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	d = container_of(work, struct rdt_domain, mbm_over.work);
+
+	list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
+		mbm_update(r, d, prgrp->mon.rmid);
+
+		head = &prgrp->mon.crdtgrp_list;
+		list_for_each_entry(crgrp, head, mon.crdtgrp_list)
+			mbm_update(r, d, crgrp->mon.rmid);
+
+		if (is_mba_sc(NULL))
+			update_mba_bw(prgrp, d);
+	}
+
+	schedule_delayed_work_on(cpu, &d->mbm_over, delay);
+
+out_unlock:
+	mutex_unlock(&rdtgroup_mutex);
+}
+
+void mbm_setup_overflow_handler(struct rdt_domain *dom, unsigned long delay_ms)
+{
+	unsigned long delay = msecs_to_jiffies(delay_ms);
+	int cpu;
+
+	if (!static_branch_likely(&rdt_mon_enable_key))
+		return;
+	cpu = cpumask_any(&dom->cpu_mask);
+	dom->mbm_work_cpu = cpu;
+	schedule_delayed_work_on(cpu, &dom->mbm_over, delay);
+}
+
+static int dom_data_init(struct rdt_resource *r)
+{
+	struct rmid_entry *entry = NULL;
+	int i, nr_rmids;
+
+	nr_rmids = r->num_rmid;
+	rmid_ptrs = kcalloc(nr_rmids, sizeof(struct rmid_entry), GFP_KERNEL);
+	if (!rmid_ptrs)
+		return -ENOMEM;
+
+	for (i = 0; i < nr_rmids; i++) {
+		entry = &rmid_ptrs[i];
+		INIT_LIST_HEAD(&entry->list);
+
+		entry->rmid = i;
+		list_add_tail(&entry->list, &rmid_free_lru);
+	}
+
+	/*
+	 * RMID 0 is special and is always allocated. It's used for all
+	 * tasks that are not monitored.
+	 */
+	entry = __rmid_entry(0);
+	list_del(&entry->list);
+
+	return 0;
+}
+
+static struct mon_evt llc_occupancy_event = {
+	.name		= "llc_occupancy",
+	.evtid		= QOS_L3_OCCUP_EVENT_ID,
+};
+
+static struct mon_evt mbm_total_event = {
+	.name		= "mbm_total_bytes",
+	.evtid		= QOS_L3_MBM_TOTAL_EVENT_ID,
+};
+
+static struct mon_evt mbm_local_event = {
+	.name		= "mbm_local_bytes",
+	.evtid		= QOS_L3_MBM_LOCAL_EVENT_ID,
+};
+
+/*
+ * Initialize the event list for the resource.
+ *
+ * Note that MBM events are also part of RDT_RESOURCE_L3 resource
+ * because as per the SDM the total and local memory bandwidth
+ * are enumerated as part of L3 monitoring.
+ */
+static void l3_mon_evt_init(struct rdt_resource *r)
+{
+	INIT_LIST_HEAD(&r->evt_list);
+
+	if (is_llc_occupancy_enabled())
+		list_add_tail(&llc_occupancy_event.list, &r->evt_list);
+	if (is_mbm_total_enabled())
+		list_add_tail(&mbm_total_event.list, &r->evt_list);
+	if (is_mbm_local_enabled())
+		list_add_tail(&mbm_local_event.list, &r->evt_list);
+}
+
+int __init rdt_get_mon_l3_config(struct rdt_resource *r)
+{
+	unsigned int mbm_offset = boot_cpu_data.x86_cache_mbm_width_offset;
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+	unsigned int threshold;
+	int ret;
+
+	resctrl_rmid_realloc_limit = boot_cpu_data.x86_cache_size * 1024;
+	hw_res->mon_scale = boot_cpu_data.x86_cache_occ_scale;
+	r->num_rmid = boot_cpu_data.x86_cache_max_rmid + 1;
+	hw_res->mbm_width = MBM_CNTR_WIDTH_BASE;
+
+	if (mbm_offset > 0 && mbm_offset <= MBM_CNTR_WIDTH_OFFSET_MAX)
+		hw_res->mbm_width += mbm_offset;
+	else if (mbm_offset > MBM_CNTR_WIDTH_OFFSET_MAX)
+		pr_warn("Ignoring impossible MBM counter offset\n");
+
+	/*
+	 * A reasonable upper limit on the max threshold is the number
+	 * of lines tagged per RMID if all RMIDs have the same number of
+	 * lines tagged in the LLC.
+	 *
+	 * For a 35MB LLC and 56 RMIDs, this is ~1.8% of the LLC.
+	 */
+	threshold = resctrl_rmid_realloc_limit / r->num_rmid;
+
+	/*
+	 * Because num_rmid may not be a power of two, round the value
+	 * to the nearest multiple of hw_res->mon_scale so it matches a
+	 * value the hardware will measure. mon_scale may not be a power of 2.
+	 */
+	resctrl_rmid_realloc_threshold = resctrl_arch_round_mon_val(threshold);
+
+	ret = dom_data_init(r);
+	if (ret)
+		return ret;
+
+	if (rdt_cpu_has(X86_FEATURE_BMEC)) {
+		if (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL)) {
+			mbm_total_event.configurable = true;
+			mbm_config_rftype_init("mbm_total_bytes_config");
+		}
+		if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL)) {
+			mbm_local_event.configurable = true;
+			mbm_config_rftype_init("mbm_local_bytes_config");
+		}
+	}
+
+	l3_mon_evt_init(r);
+
+	r->mon_capable = true;
+
+	return 0;
+}
+
+void __init intel_rdt_mbm_apply_quirk(void)
+{
+	int cf_index;
+
+	cf_index = (boot_cpu_data.x86_cache_max_rmid + 1) / 8 - 1;
+	if (cf_index >= ARRAY_SIZE(mbm_cf_table)) {
+		pr_info("No MBM correction factor available\n");
+		return;
+	}
+
+	mbm_cf_rmidthreshold = mbm_cf_table[cf_index].rmidthreshold;
+	mbm_cf = mbm_cf_table[cf_index].cf;
+}
diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
new file mode 100644
index 0000000000..8f559eeae0
--- /dev/null
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
@@ -0,0 +1,1601 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Resource Director Technology (RDT)
+ *
+ * Pseudo-locking support built on top of Cache Allocation Technology (CAT)
+ *
+ * Copyright (C) 2018 Intel Corporation
+ *
+ * Author: Reinette Chatre <reinette.chatre@intel.com>
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/cacheinfo.h>
+#include <linux/cpu.h>
+#include <linux/cpumask.h>
+#include <linux/debugfs.h>
+#include <linux/kthread.h>
+#include <linux/mman.h>
+#include <linux/perf_event.h>
+#include <linux/pm_qos.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+#include <asm/cacheflush.h>
+#include <asm/intel-family.h>
+#include <asm/resctrl.h>
+#include <asm/perf_event.h>
+
+#include "../../events/perf_event.h" /* For X86_CONFIG() */
+#include "internal.h"
+
+#define CREATE_TRACE_POINTS
+#include "pseudo_lock_event.h"
+
+/*
+ * The bits needed to disable hardware prefetching varies based on the
+ * platform. During initialization we will discover which bits to use.
+ */
+static u64 prefetch_disable_bits;
+
+/*
+ * Major number assigned to and shared by all devices exposing
+ * pseudo-locked regions.
+ */
+static unsigned int pseudo_lock_major;
+static unsigned long pseudo_lock_minor_avail = GENMASK(MINORBITS, 0);
+
+static char *pseudo_lock_devnode(const struct device *dev, umode_t *mode)
+{
+	const struct rdtgroup *rdtgrp;
+
+	rdtgrp = dev_get_drvdata(dev);
+	if (mode)
+		*mode = 0600;
+	return kasprintf(GFP_KERNEL, "pseudo_lock/%s", rdtgrp->kn->name);
+}
+
+static const struct class pseudo_lock_class = {
+	.name = "pseudo_lock",
+	.devnode = pseudo_lock_devnode,
+};
+
+/**
+ * get_prefetch_disable_bits - prefetch disable bits of supported platforms
+ * @void: It takes no parameters.
+ *
+ * Capture the list of platforms that have been validated to support
+ * pseudo-locking. This includes testing to ensure pseudo-locked regions
+ * with low cache miss rates can be created under variety of load conditions
+ * as well as that these pseudo-locked regions can maintain their low cache
+ * miss rates under variety of load conditions for significant lengths of time.
+ *
+ * After a platform has been validated to support pseudo-locking its
+ * hardware prefetch disable bits are included here as they are documented
+ * in the SDM.
+ *
+ * When adding a platform here also add support for its cache events to
+ * measure_cycles_perf_fn()
+ *
+ * Return:
+ * If platform is supported, the bits to disable hardware prefetchers, 0
+ * if platform is not supported.
+ */
+static u64 get_prefetch_disable_bits(void)
+{
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL ||
+	    boot_cpu_data.x86 != 6)
+		return 0;
+
+	switch (boot_cpu_data.x86_model) {
+	case INTEL_FAM6_BROADWELL_X:
+		/*
+		 * SDM defines bits of MSR_MISC_FEATURE_CONTROL register
+		 * as:
+		 * 0    L2 Hardware Prefetcher Disable (R/W)
+		 * 1    L2 Adjacent Cache Line Prefetcher Disable (R/W)
+		 * 2    DCU Hardware Prefetcher Disable (R/W)
+		 * 3    DCU IP Prefetcher Disable (R/W)
+		 * 63:4 Reserved
+		 */
+		return 0xF;
+	case INTEL_FAM6_ATOM_GOLDMONT:
+	case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
+		/*
+		 * SDM defines bits of MSR_MISC_FEATURE_CONTROL register
+		 * as:
+		 * 0     L2 Hardware Prefetcher Disable (R/W)
+		 * 1     Reserved
+		 * 2     DCU Hardware Prefetcher Disable (R/W)
+		 * 63:3  Reserved
+		 */
+		return 0x5;
+	}
+
+	return 0;
+}
+
+/**
+ * pseudo_lock_minor_get - Obtain available minor number
+ * @minor: Pointer to where new minor number will be stored
+ *
+ * A bitmask is used to track available minor numbers. Here the next free
+ * minor number is marked as unavailable and returned.
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+static int pseudo_lock_minor_get(unsigned int *minor)
+{
+	unsigned long first_bit;
+
+	first_bit = find_first_bit(&pseudo_lock_minor_avail, MINORBITS);
+
+	if (first_bit == MINORBITS)
+		return -ENOSPC;
+
+	__clear_bit(first_bit, &pseudo_lock_minor_avail);
+	*minor = first_bit;
+
+	return 0;
+}
+
+/**
+ * pseudo_lock_minor_release - Return minor number to available
+ * @minor: The minor number made available
+ */
+static void pseudo_lock_minor_release(unsigned int minor)
+{
+	__set_bit(minor, &pseudo_lock_minor_avail);
+}
+
+/**
+ * region_find_by_minor - Locate a pseudo-lock region by inode minor number
+ * @minor: The minor number of the device representing pseudo-locked region
+ *
+ * When the character device is accessed we need to determine which
+ * pseudo-locked region it belongs to. This is done by matching the minor
+ * number of the device to the pseudo-locked region it belongs.
+ *
+ * Minor numbers are assigned at the time a pseudo-locked region is associated
+ * with a cache instance.
+ *
+ * Return: On success return pointer to resource group owning the pseudo-locked
+ *         region, NULL on failure.
+ */
+static struct rdtgroup *region_find_by_minor(unsigned int minor)
+{
+	struct rdtgroup *rdtgrp, *rdtgrp_match = NULL;
+
+	list_for_each_entry(rdtgrp, &rdt_all_groups, rdtgroup_list) {
+		if (rdtgrp->plr && rdtgrp->plr->minor == minor) {
+			rdtgrp_match = rdtgrp;
+			break;
+		}
+	}
+	return rdtgrp_match;
+}
+
+/**
+ * struct pseudo_lock_pm_req - A power management QoS request list entry
+ * @list:	Entry within the @pm_reqs list for a pseudo-locked region
+ * @req:	PM QoS request
+ */
+struct pseudo_lock_pm_req {
+	struct list_head list;
+	struct dev_pm_qos_request req;
+};
+
+static void pseudo_lock_cstates_relax(struct pseudo_lock_region *plr)
+{
+	struct pseudo_lock_pm_req *pm_req, *next;
+
+	list_for_each_entry_safe(pm_req, next, &plr->pm_reqs, list) {
+		dev_pm_qos_remove_request(&pm_req->req);
+		list_del(&pm_req->list);
+		kfree(pm_req);
+	}
+}
+
+/**
+ * pseudo_lock_cstates_constrain - Restrict cores from entering C6
+ * @plr: Pseudo-locked region
+ *
+ * To prevent the cache from being affected by power management entering
+ * C6 has to be avoided. This is accomplished by requesting a latency
+ * requirement lower than lowest C6 exit latency of all supported
+ * platforms as found in the cpuidle state tables in the intel_idle driver.
+ * At this time it is possible to do so with a single latency requirement
+ * for all supported platforms.
+ *
+ * Since Goldmont is supported, which is affected by X86_BUG_MONITOR,
+ * the ACPI latencies need to be considered while keeping in mind that C2
+ * may be set to map to deeper sleep states. In this case the latency
+ * requirement needs to prevent entering C2 also.
+ *
+ * Return: 0 on success, <0 on failure
+ */
+static int pseudo_lock_cstates_constrain(struct pseudo_lock_region *plr)
+{
+	struct pseudo_lock_pm_req *pm_req;
+	int cpu;
+	int ret;
+
+	for_each_cpu(cpu, &plr->d->cpu_mask) {
+		pm_req = kzalloc(sizeof(*pm_req), GFP_KERNEL);
+		if (!pm_req) {
+			rdt_last_cmd_puts("Failure to allocate memory for PM QoS\n");
+			ret = -ENOMEM;
+			goto out_err;
+		}
+		ret = dev_pm_qos_add_request(get_cpu_device(cpu),
+					     &pm_req->req,
+					     DEV_PM_QOS_RESUME_LATENCY,
+					     30);
+		if (ret < 0) {
+			rdt_last_cmd_printf("Failed to add latency req CPU%d\n",
+					    cpu);
+			kfree(pm_req);
+			ret = -1;
+			goto out_err;
+		}
+		list_add(&pm_req->list, &plr->pm_reqs);
+	}
+
+	return 0;
+
+out_err:
+	pseudo_lock_cstates_relax(plr);
+	return ret;
+}
+
+/**
+ * pseudo_lock_region_clear - Reset pseudo-lock region data
+ * @plr: pseudo-lock region
+ *
+ * All content of the pseudo-locked region is reset - any memory allocated
+ * freed.
+ *
+ * Return: void
+ */
+static void pseudo_lock_region_clear(struct pseudo_lock_region *plr)
+{
+	plr->size = 0;
+	plr->line_size = 0;
+	kfree(plr->kmem);
+	plr->kmem = NULL;
+	plr->s = NULL;
+	if (plr->d)
+		plr->d->plr = NULL;
+	plr->d = NULL;
+	plr->cbm = 0;
+	plr->debugfs_dir = NULL;
+}
+
+/**
+ * pseudo_lock_region_init - Initialize pseudo-lock region information
+ * @plr: pseudo-lock region
+ *
+ * Called after user provided a schemata to be pseudo-locked. From the
+ * schemata the &struct pseudo_lock_region is on entry already initialized
+ * with the resource, domain, and capacity bitmask. Here the information
+ * required for pseudo-locking is deduced from this data and &struct
+ * pseudo_lock_region initialized further. This information includes:
+ * - size in bytes of the region to be pseudo-locked
+ * - cache line size to know the stride with which data needs to be accessed
+ *   to be pseudo-locked
+ * - a cpu associated with the cache instance on which the pseudo-locking
+ *   flow can be executed
+ *
+ * Return: 0 on success, <0 on failure. Descriptive error will be written
+ * to last_cmd_status buffer.
+ */
+static int pseudo_lock_region_init(struct pseudo_lock_region *plr)
+{
+	struct cpu_cacheinfo *ci;
+	int ret;
+	int i;
+
+	/* Pick the first cpu we find that is associated with the cache. */
+	plr->cpu = cpumask_first(&plr->d->cpu_mask);
+
+	if (!cpu_online(plr->cpu)) {
+		rdt_last_cmd_printf("CPU %u associated with cache not online\n",
+				    plr->cpu);
+		ret = -ENODEV;
+		goto out_region;
+	}
+
+	ci = get_cpu_cacheinfo(plr->cpu);
+
+	plr->size = rdtgroup_cbm_to_size(plr->s->res, plr->d, plr->cbm);
+
+	for (i = 0; i < ci->num_leaves; i++) {
+		if (ci->info_list[i].level == plr->s->res->cache_level) {
+			plr->line_size = ci->info_list[i].coherency_line_size;
+			return 0;
+		}
+	}
+
+	ret = -1;
+	rdt_last_cmd_puts("Unable to determine cache line size\n");
+out_region:
+	pseudo_lock_region_clear(plr);
+	return ret;
+}
+
+/**
+ * pseudo_lock_init - Initialize a pseudo-lock region
+ * @rdtgrp: resource group to which new pseudo-locked region will belong
+ *
+ * A pseudo-locked region is associated with a resource group. When this
+ * association is created the pseudo-locked region is initialized. The
+ * details of the pseudo-locked region are not known at this time so only
+ * allocation is done and association established.
+ *
+ * Return: 0 on success, <0 on failure
+ */
+static int pseudo_lock_init(struct rdtgroup *rdtgrp)
+{
+	struct pseudo_lock_region *plr;
+
+	plr = kzalloc(sizeof(*plr), GFP_KERNEL);
+	if (!plr)
+		return -ENOMEM;
+
+	init_waitqueue_head(&plr->lock_thread_wq);
+	INIT_LIST_HEAD(&plr->pm_reqs);
+	rdtgrp->plr = plr;
+	return 0;
+}
+
+/**
+ * pseudo_lock_region_alloc - Allocate kernel memory that will be pseudo-locked
+ * @plr: pseudo-lock region
+ *
+ * Initialize the details required to set up the pseudo-locked region and
+ * allocate the contiguous memory that will be pseudo-locked to the cache.
+ *
+ * Return: 0 on success, <0 on failure.  Descriptive error will be written
+ * to last_cmd_status buffer.
+ */
+static int pseudo_lock_region_alloc(struct pseudo_lock_region *plr)
+{
+	int ret;
+
+	ret = pseudo_lock_region_init(plr);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * We do not yet support contiguous regions larger than
+	 * KMALLOC_MAX_SIZE.
+	 */
+	if (plr->size > KMALLOC_MAX_SIZE) {
+		rdt_last_cmd_puts("Requested region exceeds maximum size\n");
+		ret = -E2BIG;
+		goto out_region;
+	}
+
+	plr->kmem = kzalloc(plr->size, GFP_KERNEL);
+	if (!plr->kmem) {
+		rdt_last_cmd_puts("Unable to allocate memory\n");
+		ret = -ENOMEM;
+		goto out_region;
+	}
+
+	ret = 0;
+	goto out;
+out_region:
+	pseudo_lock_region_clear(plr);
+out:
+	return ret;
+}
+
+/**
+ * pseudo_lock_free - Free a pseudo-locked region
+ * @rdtgrp: resource group to which pseudo-locked region belonged
+ *
+ * The pseudo-locked region's resources have already been released, or not
+ * yet created at this point. Now it can be freed and disassociated from the
+ * resource group.
+ *
+ * Return: void
+ */
+static void pseudo_lock_free(struct rdtgroup *rdtgrp)
+{
+	pseudo_lock_region_clear(rdtgrp->plr);
+	kfree(rdtgrp->plr);
+	rdtgrp->plr = NULL;
+}
+
+/**
+ * pseudo_lock_fn - Load kernel memory into cache
+ * @_rdtgrp: resource group to which pseudo-lock region belongs
+ *
+ * This is the core pseudo-locking flow.
+ *
+ * First we ensure that the kernel memory cannot be found in the cache.
+ * Then, while taking care that there will be as little interference as
+ * possible, the memory to be loaded is accessed while core is running
+ * with class of service set to the bitmask of the pseudo-locked region.
+ * After this is complete no future CAT allocations will be allowed to
+ * overlap with this bitmask.
+ *
+ * Local register variables are utilized to ensure that the memory region
+ * to be locked is the only memory access made during the critical locking
+ * loop.
+ *
+ * Return: 0. Waiter on waitqueue will be woken on completion.
+ */
+static int pseudo_lock_fn(void *_rdtgrp)
+{
+	struct rdtgroup *rdtgrp = _rdtgrp;
+	struct pseudo_lock_region *plr = rdtgrp->plr;
+	u32 rmid_p, closid_p;
+	unsigned long i;
+	u64 saved_msr;
+#ifdef CONFIG_KASAN
+	/*
+	 * The registers used for local register variables are also used
+	 * when KASAN is active. When KASAN is active we use a regular
+	 * variable to ensure we always use a valid pointer, but the cost
+	 * is that this variable will enter the cache through evicting the
+	 * memory we are trying to lock into the cache. Thus expect lower
+	 * pseudo-locking success rate when KASAN is active.
+	 */
+	unsigned int line_size;
+	unsigned int size;
+	void *mem_r;
+#else
+	register unsigned int line_size asm("esi");
+	register unsigned int size asm("edi");
+	register void *mem_r asm(_ASM_BX);
+#endif /* CONFIG_KASAN */
+
+	/*
+	 * Make sure none of the allocated memory is cached. If it is we
+	 * will get a cache hit in below loop from outside of pseudo-locked
+	 * region.
+	 * wbinvd (as opposed to clflush/clflushopt) is required to
+	 * increase likelihood that allocated cache portion will be filled
+	 * with associated memory.
+	 */
+	native_wbinvd();
+
+	/*
+	 * Always called with interrupts enabled. By disabling interrupts
+	 * ensure that we will not be preempted during this critical section.
+	 */
+	local_irq_disable();
+
+	/*
+	 * Call wrmsr and rdmsr as directly as possible to avoid tracing
+	 * clobbering local register variables or affecting cache accesses.
+	 *
+	 * Disable the hardware prefetcher so that when the end of the memory
+	 * being pseudo-locked is reached the hardware will not read beyond
+	 * the buffer and evict pseudo-locked memory read earlier from the
+	 * cache.
+	 */
+	saved_msr = __rdmsr(MSR_MISC_FEATURE_CONTROL);
+	__wrmsr(MSR_MISC_FEATURE_CONTROL, prefetch_disable_bits, 0x0);
+	closid_p = this_cpu_read(pqr_state.cur_closid);
+	rmid_p = this_cpu_read(pqr_state.cur_rmid);
+	mem_r = plr->kmem;
+	size = plr->size;
+	line_size = plr->line_size;
+	/*
+	 * Critical section begin: start by writing the closid associated
+	 * with the capacity bitmask of the cache region being
+	 * pseudo-locked followed by reading of kernel memory to load it
+	 * into the cache.
+	 */
+	__wrmsr(MSR_IA32_PQR_ASSOC, rmid_p, rdtgrp->closid);
+	/*
+	 * Cache was flushed earlier. Now access kernel memory to read it
+	 * into cache region associated with just activated plr->closid.
+	 * Loop over data twice:
+	 * - In first loop the cache region is shared with the page walker
+	 *   as it populates the paging structure caches (including TLB).
+	 * - In the second loop the paging structure caches are used and
+	 *   cache region is populated with the memory being referenced.
+	 */
+	for (i = 0; i < size; i += PAGE_SIZE) {
+		/*
+		 * Add a barrier to prevent speculative execution of this
+		 * loop reading beyond the end of the buffer.
+		 */
+		rmb();
+		asm volatile("mov (%0,%1,1), %%eax\n\t"
+			:
+			: "r" (mem_r), "r" (i)
+			: "%eax", "memory");
+	}
+	for (i = 0; i < size; i += line_size) {
+		/*
+		 * Add a barrier to prevent speculative execution of this
+		 * loop reading beyond the end of the buffer.
+		 */
+		rmb();
+		asm volatile("mov (%0,%1,1), %%eax\n\t"
+			:
+			: "r" (mem_r), "r" (i)
+			: "%eax", "memory");
+	}
+	/*
+	 * Critical section end: restore closid with capacity bitmask that
+	 * does not overlap with pseudo-locked region.
+	 */
+	__wrmsr(MSR_IA32_PQR_ASSOC, rmid_p, closid_p);
+
+	/* Re-enable the hardware prefetcher(s) */
+	wrmsrl(MSR_MISC_FEATURE_CONTROL, saved_msr);
+	local_irq_enable();
+
+	plr->thread_done = 1;
+	wake_up_interruptible(&plr->lock_thread_wq);
+	return 0;
+}
+
+/**
+ * rdtgroup_monitor_in_progress - Test if monitoring in progress
+ * @rdtgrp: resource group being queried
+ *
+ * Return: 1 if monitor groups have been created for this resource
+ * group, 0 otherwise.
+ */
+static int rdtgroup_monitor_in_progress(struct rdtgroup *rdtgrp)
+{
+	return !list_empty(&rdtgrp->mon.crdtgrp_list);
+}
+
+/**
+ * rdtgroup_locksetup_user_restrict - Restrict user access to group
+ * @rdtgrp: resource group needing access restricted
+ *
+ * A resource group used for cache pseudo-locking cannot have cpus or tasks
+ * assigned to it. This is communicated to the user by restricting access
+ * to all the files that can be used to make such changes.
+ *
+ * Permissions restored with rdtgroup_locksetup_user_restore()
+ *
+ * Return: 0 on success, <0 on failure. If a failure occurs during the
+ * restriction of access an attempt will be made to restore permissions but
+ * the state of the mode of these files will be uncertain when a failure
+ * occurs.
+ */
+static int rdtgroup_locksetup_user_restrict(struct rdtgroup *rdtgrp)
+{
+	int ret;
+
+	ret = rdtgroup_kn_mode_restrict(rdtgrp, "tasks");
+	if (ret)
+		return ret;
+
+	ret = rdtgroup_kn_mode_restrict(rdtgrp, "cpus");
+	if (ret)
+		goto err_tasks;
+
+	ret = rdtgroup_kn_mode_restrict(rdtgrp, "cpus_list");
+	if (ret)
+		goto err_cpus;
+
+	if (rdt_mon_capable) {
+		ret = rdtgroup_kn_mode_restrict(rdtgrp, "mon_groups");
+		if (ret)
+			goto err_cpus_list;
+	}
+
+	ret = 0;
+	goto out;
+
+err_cpus_list:
+	rdtgroup_kn_mode_restore(rdtgrp, "cpus_list", 0777);
+err_cpus:
+	rdtgroup_kn_mode_restore(rdtgrp, "cpus", 0777);
+err_tasks:
+	rdtgroup_kn_mode_restore(rdtgrp, "tasks", 0777);
+out:
+	return ret;
+}
+
+/**
+ * rdtgroup_locksetup_user_restore - Restore user access to group
+ * @rdtgrp: resource group needing access restored
+ *
+ * Restore all file access previously removed using
+ * rdtgroup_locksetup_user_restrict()
+ *
+ * Return: 0 on success, <0 on failure.  If a failure occurs during the
+ * restoration of access an attempt will be made to restrict permissions
+ * again but the state of the mode of these files will be uncertain when
+ * a failure occurs.
+ */
+static int rdtgroup_locksetup_user_restore(struct rdtgroup *rdtgrp)
+{
+	int ret;
+
+	ret = rdtgroup_kn_mode_restore(rdtgrp, "tasks", 0777);
+	if (ret)
+		return ret;
+
+	ret = rdtgroup_kn_mode_restore(rdtgrp, "cpus", 0777);
+	if (ret)
+		goto err_tasks;
+
+	ret = rdtgroup_kn_mode_restore(rdtgrp, "cpus_list", 0777);
+	if (ret)
+		goto err_cpus;
+
+	if (rdt_mon_capable) {
+		ret = rdtgroup_kn_mode_restore(rdtgrp, "mon_groups", 0777);
+		if (ret)
+			goto err_cpus_list;
+	}
+
+	ret = 0;
+	goto out;
+
+err_cpus_list:
+	rdtgroup_kn_mode_restrict(rdtgrp, "cpus_list");
+err_cpus:
+	rdtgroup_kn_mode_restrict(rdtgrp, "cpus");
+err_tasks:
+	rdtgroup_kn_mode_restrict(rdtgrp, "tasks");
+out:
+	return ret;
+}
+
+/**
+ * rdtgroup_locksetup_enter - Resource group enters locksetup mode
+ * @rdtgrp: resource group requested to enter locksetup mode
+ *
+ * A resource group enters locksetup mode to reflect that it would be used
+ * to represent a pseudo-locked region and is in the process of being set
+ * up to do so. A resource group used for a pseudo-locked region would
+ * lose the closid associated with it so we cannot allow it to have any
+ * tasks or cpus assigned nor permit tasks or cpus to be assigned in the
+ * future. Monitoring of a pseudo-locked region is not allowed either.
+ *
+ * The above and more restrictions on a pseudo-locked region are checked
+ * for and enforced before the resource group enters the locksetup mode.
+ *
+ * Returns: 0 if the resource group successfully entered locksetup mode, <0
+ * on failure. On failure the last_cmd_status buffer is updated with text to
+ * communicate details of failure to the user.
+ */
+int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp)
+{
+	int ret;
+
+	/*
+	 * The default resource group can neither be removed nor lose the
+	 * default closid associated with it.
+	 */
+	if (rdtgrp == &rdtgroup_default) {
+		rdt_last_cmd_puts("Cannot pseudo-lock default group\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Cache Pseudo-locking not supported when CDP is enabled.
+	 *
+	 * Some things to consider if you would like to enable this
+	 * support (using L3 CDP as example):
+	 * - When CDP is enabled two separate resources are exposed,
+	 *   L3DATA and L3CODE, but they are actually on the same cache.
+	 *   The implication for pseudo-locking is that if a
+	 *   pseudo-locked region is created on a domain of one
+	 *   resource (eg. L3CODE), then a pseudo-locked region cannot
+	 *   be created on that same domain of the other resource
+	 *   (eg. L3DATA). This is because the creation of a
+	 *   pseudo-locked region involves a call to wbinvd that will
+	 *   affect all cache allocations on particular domain.
+	 * - Considering the previous, it may be possible to only
+	 *   expose one of the CDP resources to pseudo-locking and
+	 *   hide the other. For example, we could consider to only
+	 *   expose L3DATA and since the L3 cache is unified it is
+	 *   still possible to place instructions there are execute it.
+	 * - If only one region is exposed to pseudo-locking we should
+	 *   still keep in mind that availability of a portion of cache
+	 *   for pseudo-locking should take into account both resources.
+	 *   Similarly, if a pseudo-locked region is created in one
+	 *   resource, the portion of cache used by it should be made
+	 *   unavailable to all future allocations from both resources.
+	 */
+	if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L3) ||
+	    resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L2)) {
+		rdt_last_cmd_puts("CDP enabled\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Not knowing the bits to disable prefetching implies that this
+	 * platform does not support Cache Pseudo-Locking.
+	 */
+	prefetch_disable_bits = get_prefetch_disable_bits();
+	if (prefetch_disable_bits == 0) {
+		rdt_last_cmd_puts("Pseudo-locking not supported\n");
+		return -EINVAL;
+	}
+
+	if (rdtgroup_monitor_in_progress(rdtgrp)) {
+		rdt_last_cmd_puts("Monitoring in progress\n");
+		return -EINVAL;
+	}
+
+	if (rdtgroup_tasks_assigned(rdtgrp)) {
+		rdt_last_cmd_puts("Tasks assigned to resource group\n");
+		return -EINVAL;
+	}
+
+	if (!cpumask_empty(&rdtgrp->cpu_mask)) {
+		rdt_last_cmd_puts("CPUs assigned to resource group\n");
+		return -EINVAL;
+	}
+
+	if (rdtgroup_locksetup_user_restrict(rdtgrp)) {
+		rdt_last_cmd_puts("Unable to modify resctrl permissions\n");
+		return -EIO;
+	}
+
+	ret = pseudo_lock_init(rdtgrp);
+	if (ret) {
+		rdt_last_cmd_puts("Unable to init pseudo-lock region\n");
+		goto out_release;
+	}
+
+	/*
+	 * If this system is capable of monitoring a rmid would have been
+	 * allocated when the control group was created. This is not needed
+	 * anymore when this group would be used for pseudo-locking. This
+	 * is safe to call on platforms not capable of monitoring.
+	 */
+	free_rmid(rdtgrp->mon.rmid);
+
+	ret = 0;
+	goto out;
+
+out_release:
+	rdtgroup_locksetup_user_restore(rdtgrp);
+out:
+	return ret;
+}
+
+/**
+ * rdtgroup_locksetup_exit - resource group exist locksetup mode
+ * @rdtgrp: resource group
+ *
+ * When a resource group exits locksetup mode the earlier restrictions are
+ * lifted.
+ *
+ * Return: 0 on success, <0 on failure
+ */
+int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp)
+{
+	int ret;
+
+	if (rdt_mon_capable) {
+		ret = alloc_rmid();
+		if (ret < 0) {
+			rdt_last_cmd_puts("Out of RMIDs\n");
+			return ret;
+		}
+		rdtgrp->mon.rmid = ret;
+	}
+
+	ret = rdtgroup_locksetup_user_restore(rdtgrp);
+	if (ret) {
+		free_rmid(rdtgrp->mon.rmid);
+		return ret;
+	}
+
+	pseudo_lock_free(rdtgrp);
+	return 0;
+}
+
+/**
+ * rdtgroup_cbm_overlaps_pseudo_locked - Test if CBM or portion is pseudo-locked
+ * @d: RDT domain
+ * @cbm: CBM to test
+ *
+ * @d represents a cache instance and @cbm a capacity bitmask that is
+ * considered for it. Determine if @cbm overlaps with any existing
+ * pseudo-locked region on @d.
+ *
+ * @cbm is unsigned long, even if only 32 bits are used, to make the
+ * bitmap functions work correctly.
+ *
+ * Return: true if @cbm overlaps with pseudo-locked region on @d, false
+ * otherwise.
+ */
+bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_domain *d, unsigned long cbm)
+{
+	unsigned int cbm_len;
+	unsigned long cbm_b;
+
+	if (d->plr) {
+		cbm_len = d->plr->s->res->cache.cbm_len;
+		cbm_b = d->plr->cbm;
+		if (bitmap_intersects(&cbm, &cbm_b, cbm_len))
+			return true;
+	}
+	return false;
+}
+
+/**
+ * rdtgroup_pseudo_locked_in_hierarchy - Pseudo-locked region in cache hierarchy
+ * @d: RDT domain under test
+ *
+ * The setup of a pseudo-locked region affects all cache instances within
+ * the hierarchy of the region. It is thus essential to know if any
+ * pseudo-locked regions exist within a cache hierarchy to prevent any
+ * attempts to create new pseudo-locked regions in the same hierarchy.
+ *
+ * Return: true if a pseudo-locked region exists in the hierarchy of @d or
+ *         if it is not possible to test due to memory allocation issue,
+ *         false otherwise.
+ */
+bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_domain *d)
+{
+	cpumask_var_t cpu_with_psl;
+	struct rdt_resource *r;
+	struct rdt_domain *d_i;
+	bool ret = false;
+
+	if (!zalloc_cpumask_var(&cpu_with_psl, GFP_KERNEL))
+		return true;
+
+	/*
+	 * First determine which cpus have pseudo-locked regions
+	 * associated with them.
+	 */
+	for_each_alloc_capable_rdt_resource(r) {
+		list_for_each_entry(d_i, &r->domains, list) {
+			if (d_i->plr)
+				cpumask_or(cpu_with_psl, cpu_with_psl,
+					   &d_i->cpu_mask);
+		}
+	}
+
+	/*
+	 * Next test if new pseudo-locked region would intersect with
+	 * existing region.
+	 */
+	if (cpumask_intersects(&d->cpu_mask, cpu_with_psl))
+		ret = true;
+
+	free_cpumask_var(cpu_with_psl);
+	return ret;
+}
+
+/**
+ * measure_cycles_lat_fn - Measure cycle latency to read pseudo-locked memory
+ * @_plr: pseudo-lock region to measure
+ *
+ * There is no deterministic way to test if a memory region is cached. One
+ * way is to measure how long it takes to read the memory, the speed of
+ * access is a good way to learn how close to the cpu the data was. Even
+ * more, if the prefetcher is disabled and the memory is read at a stride
+ * of half the cache line, then a cache miss will be easy to spot since the
+ * read of the first half would be significantly slower than the read of
+ * the second half.
+ *
+ * Return: 0. Waiter on waitqueue will be woken on completion.
+ */
+static int measure_cycles_lat_fn(void *_plr)
+{
+	struct pseudo_lock_region *plr = _plr;
+	u32 saved_low, saved_high;
+	unsigned long i;
+	u64 start, end;
+	void *mem_r;
+
+	local_irq_disable();
+	/*
+	 * Disable hardware prefetchers.
+	 */
+	rdmsr(MSR_MISC_FEATURE_CONTROL, saved_low, saved_high);
+	wrmsr(MSR_MISC_FEATURE_CONTROL, prefetch_disable_bits, 0x0);
+	mem_r = READ_ONCE(plr->kmem);
+	/*
+	 * Dummy execute of the time measurement to load the needed
+	 * instructions into the L1 instruction cache.
+	 */
+	start = rdtsc_ordered();
+	for (i = 0; i < plr->size; i += 32) {
+		start = rdtsc_ordered();
+		asm volatile("mov (%0,%1,1), %%eax\n\t"
+			     :
+			     : "r" (mem_r), "r" (i)
+			     : "%eax", "memory");
+		end = rdtsc_ordered();
+		trace_pseudo_lock_mem_latency((u32)(end - start));
+	}
+	wrmsr(MSR_MISC_FEATURE_CONTROL, saved_low, saved_high);
+	local_irq_enable();
+	plr->thread_done = 1;
+	wake_up_interruptible(&plr->lock_thread_wq);
+	return 0;
+}
+
+/*
+ * Create a perf_event_attr for the hit and miss perf events that will
+ * be used during the performance measurement. A perf_event maintains
+ * a pointer to its perf_event_attr so a unique attribute structure is
+ * created for each perf_event.
+ *
+ * The actual configuration of the event is set right before use in order
+ * to use the X86_CONFIG macro.
+ */
+static struct perf_event_attr perf_miss_attr = {
+	.type		= PERF_TYPE_RAW,
+	.size		= sizeof(struct perf_event_attr),
+	.pinned		= 1,
+	.disabled	= 0,
+	.exclude_user	= 1,
+};
+
+static struct perf_event_attr perf_hit_attr = {
+	.type		= PERF_TYPE_RAW,
+	.size		= sizeof(struct perf_event_attr),
+	.pinned		= 1,
+	.disabled	= 0,
+	.exclude_user	= 1,
+};
+
+struct residency_counts {
+	u64 miss_before, hits_before;
+	u64 miss_after,  hits_after;
+};
+
+static int measure_residency_fn(struct perf_event_attr *miss_attr,
+				struct perf_event_attr *hit_attr,
+				struct pseudo_lock_region *plr,
+				struct residency_counts *counts)
+{
+	u64 hits_before = 0, hits_after = 0, miss_before = 0, miss_after = 0;
+	struct perf_event *miss_event, *hit_event;
+	int hit_pmcnum, miss_pmcnum;
+	u32 saved_low, saved_high;
+	unsigned int line_size;
+	unsigned int size;
+	unsigned long i;
+	void *mem_r;
+	u64 tmp;
+
+	miss_event = perf_event_create_kernel_counter(miss_attr, plr->cpu,
+						      NULL, NULL, NULL);
+	if (IS_ERR(miss_event))
+		goto out;
+
+	hit_event = perf_event_create_kernel_counter(hit_attr, plr->cpu,
+						     NULL, NULL, NULL);
+	if (IS_ERR(hit_event))
+		goto out_miss;
+
+	local_irq_disable();
+	/*
+	 * Check any possible error state of events used by performing
+	 * one local read.
+	 */
+	if (perf_event_read_local(miss_event, &tmp, NULL, NULL)) {
+		local_irq_enable();
+		goto out_hit;
+	}
+	if (perf_event_read_local(hit_event, &tmp, NULL, NULL)) {
+		local_irq_enable();
+		goto out_hit;
+	}
+
+	/*
+	 * Disable hardware prefetchers.
+	 */
+	rdmsr(MSR_MISC_FEATURE_CONTROL, saved_low, saved_high);
+	wrmsr(MSR_MISC_FEATURE_CONTROL, prefetch_disable_bits, 0x0);
+
+	/* Initialize rest of local variables */
+	/*
+	 * Performance event has been validated right before this with
+	 * interrupts disabled - it is thus safe to read the counter index.
+	 */
+	miss_pmcnum = x86_perf_rdpmc_index(miss_event);
+	hit_pmcnum = x86_perf_rdpmc_index(hit_event);
+	line_size = READ_ONCE(plr->line_size);
+	mem_r = READ_ONCE(plr->kmem);
+	size = READ_ONCE(plr->size);
+
+	/*
+	 * Read counter variables twice - first to load the instructions
+	 * used in L1 cache, second to capture accurate value that does not
+	 * include cache misses incurred because of instruction loads.
+	 */
+	rdpmcl(hit_pmcnum, hits_before);
+	rdpmcl(miss_pmcnum, miss_before);
+	/*
+	 * From SDM: Performing back-to-back fast reads are not guaranteed
+	 * to be monotonic.
+	 * Use LFENCE to ensure all previous instructions are retired
+	 * before proceeding.
+	 */
+	rmb();
+	rdpmcl(hit_pmcnum, hits_before);
+	rdpmcl(miss_pmcnum, miss_before);
+	/*
+	 * Use LFENCE to ensure all previous instructions are retired
+	 * before proceeding.
+	 */
+	rmb();
+	for (i = 0; i < size; i += line_size) {
+		/*
+		 * Add a barrier to prevent speculative execution of this
+		 * loop reading beyond the end of the buffer.
+		 */
+		rmb();
+		asm volatile("mov (%0,%1,1), %%eax\n\t"
+			     :
+			     : "r" (mem_r), "r" (i)
+			     : "%eax", "memory");
+	}
+	/*
+	 * Use LFENCE to ensure all previous instructions are retired
+	 * before proceeding.
+	 */
+	rmb();
+	rdpmcl(hit_pmcnum, hits_after);
+	rdpmcl(miss_pmcnum, miss_after);
+	/*
+	 * Use LFENCE to ensure all previous instructions are retired
+	 * before proceeding.
+	 */
+	rmb();
+	/* Re-enable hardware prefetchers */
+	wrmsr(MSR_MISC_FEATURE_CONTROL, saved_low, saved_high);
+	local_irq_enable();
+out_hit:
+	perf_event_release_kernel(hit_event);
+out_miss:
+	perf_event_release_kernel(miss_event);
+out:
+	/*
+	 * All counts will be zero on failure.
+	 */
+	counts->miss_before = miss_before;
+	counts->hits_before = hits_before;
+	counts->miss_after  = miss_after;
+	counts->hits_after  = hits_after;
+	return 0;
+}
+
+static int measure_l2_residency(void *_plr)
+{
+	struct pseudo_lock_region *plr = _plr;
+	struct residency_counts counts = {0};
+
+	/*
+	 * Non-architectural event for the Goldmont Microarchitecture
+	 * from Intel x86 Architecture Software Developer Manual (SDM):
+	 * MEM_LOAD_UOPS_RETIRED D1H (event number)
+	 * Umask values:
+	 *     L2_HIT   02H
+	 *     L2_MISS  10H
+	 */
+	switch (boot_cpu_data.x86_model) {
+	case INTEL_FAM6_ATOM_GOLDMONT:
+	case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
+		perf_miss_attr.config = X86_CONFIG(.event = 0xd1,
+						   .umask = 0x10);
+		perf_hit_attr.config = X86_CONFIG(.event = 0xd1,
+						  .umask = 0x2);
+		break;
+	default:
+		goto out;
+	}
+
+	measure_residency_fn(&perf_miss_attr, &perf_hit_attr, plr, &counts);
+	/*
+	 * If a failure prevented the measurements from succeeding
+	 * tracepoints will still be written and all counts will be zero.
+	 */
+	trace_pseudo_lock_l2(counts.hits_after - counts.hits_before,
+			     counts.miss_after - counts.miss_before);
+out:
+	plr->thread_done = 1;
+	wake_up_interruptible(&plr->lock_thread_wq);
+	return 0;
+}
+
+static int measure_l3_residency(void *_plr)
+{
+	struct pseudo_lock_region *plr = _plr;
+	struct residency_counts counts = {0};
+
+	/*
+	 * On Broadwell Microarchitecture the MEM_LOAD_UOPS_RETIRED event
+	 * has two "no fix" errata associated with it: BDM35 and BDM100. On
+	 * this platform the following events are used instead:
+	 * LONGEST_LAT_CACHE 2EH (Documented in SDM)
+	 *       REFERENCE 4FH
+	 *       MISS      41H
+	 */
+
+	switch (boot_cpu_data.x86_model) {
+	case INTEL_FAM6_BROADWELL_X:
+		/* On BDW the hit event counts references, not hits */
+		perf_hit_attr.config = X86_CONFIG(.event = 0x2e,
+						  .umask = 0x4f);
+		perf_miss_attr.config = X86_CONFIG(.event = 0x2e,
+						   .umask = 0x41);
+		break;
+	default:
+		goto out;
+	}
+
+	measure_residency_fn(&perf_miss_attr, &perf_hit_attr, plr, &counts);
+	/*
+	 * If a failure prevented the measurements from succeeding
+	 * tracepoints will still be written and all counts will be zero.
+	 */
+
+	counts.miss_after -= counts.miss_before;
+	if (boot_cpu_data.x86_model == INTEL_FAM6_BROADWELL_X) {
+		/*
+		 * On BDW references and misses are counted, need to adjust.
+		 * Sometimes the "hits" counter is a bit more than the
+		 * references, for example, x references but x + 1 hits.
+		 * To not report invalid hit values in this case we treat
+		 * that as misses equal to references.
+		 */
+		/* First compute the number of cache references measured */
+		counts.hits_after -= counts.hits_before;
+		/* Next convert references to cache hits */
+		counts.hits_after -= min(counts.miss_after, counts.hits_after);
+	} else {
+		counts.hits_after -= counts.hits_before;
+	}
+
+	trace_pseudo_lock_l3(counts.hits_after, counts.miss_after);
+out:
+	plr->thread_done = 1;
+	wake_up_interruptible(&plr->lock_thread_wq);
+	return 0;
+}
+
+/**
+ * pseudo_lock_measure_cycles - Trigger latency measure to pseudo-locked region
+ * @rdtgrp: Resource group to which the pseudo-locked region belongs.
+ * @sel: Selector of which measurement to perform on a pseudo-locked region.
+ *
+ * The measurement of latency to access a pseudo-locked region should be
+ * done from a cpu that is associated with that pseudo-locked region.
+ * Determine which cpu is associated with this region and start a thread on
+ * that cpu to perform the measurement, wait for that thread to complete.
+ *
+ * Return: 0 on success, <0 on failure
+ */
+static int pseudo_lock_measure_cycles(struct rdtgroup *rdtgrp, int sel)
+{
+	struct pseudo_lock_region *plr = rdtgrp->plr;
+	struct task_struct *thread;
+	unsigned int cpu;
+	int ret = -1;
+
+	cpus_read_lock();
+	mutex_lock(&rdtgroup_mutex);
+
+	if (rdtgrp->flags & RDT_DELETED) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	if (!plr->d) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	plr->thread_done = 0;
+	cpu = cpumask_first(&plr->d->cpu_mask);
+	if (!cpu_online(cpu)) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	plr->cpu = cpu;
+
+	if (sel == 1)
+		thread = kthread_create_on_node(measure_cycles_lat_fn, plr,
+						cpu_to_node(cpu),
+						"pseudo_lock_measure/%u",
+						cpu);
+	else if (sel == 2)
+		thread = kthread_create_on_node(measure_l2_residency, plr,
+						cpu_to_node(cpu),
+						"pseudo_lock_measure/%u",
+						cpu);
+	else if (sel == 3)
+		thread = kthread_create_on_node(measure_l3_residency, plr,
+						cpu_to_node(cpu),
+						"pseudo_lock_measure/%u",
+						cpu);
+	else
+		goto out;
+
+	if (IS_ERR(thread)) {
+		ret = PTR_ERR(thread);
+		goto out;
+	}
+	kthread_bind(thread, cpu);
+	wake_up_process(thread);
+
+	ret = wait_event_interruptible(plr->lock_thread_wq,
+				       plr->thread_done == 1);
+	if (ret < 0)
+		goto out;
+
+	ret = 0;
+
+out:
+	mutex_unlock(&rdtgroup_mutex);
+	cpus_read_unlock();
+	return ret;
+}
+
+static ssize_t pseudo_lock_measure_trigger(struct file *file,
+					   const char __user *user_buf,
+					   size_t count, loff_t *ppos)
+{
+	struct rdtgroup *rdtgrp = file->private_data;
+	size_t buf_size;
+	char buf[32];
+	int ret;
+	int sel;
+
+	buf_size = min(count, (sizeof(buf) - 1));
+	if (copy_from_user(buf, user_buf, buf_size))
+		return -EFAULT;
+
+	buf[buf_size] = '\0';
+	ret = kstrtoint(buf, 10, &sel);
+	if (ret == 0) {
+		if (sel != 1 && sel != 2 && sel != 3)
+			return -EINVAL;
+		ret = debugfs_file_get(file->f_path.dentry);
+		if (ret)
+			return ret;
+		ret = pseudo_lock_measure_cycles(rdtgrp, sel);
+		if (ret == 0)
+			ret = count;
+		debugfs_file_put(file->f_path.dentry);
+	}
+
+	return ret;
+}
+
+static const struct file_operations pseudo_measure_fops = {
+	.write = pseudo_lock_measure_trigger,
+	.open = simple_open,
+	.llseek = default_llseek,
+};
+
+/**
+ * rdtgroup_pseudo_lock_create - Create a pseudo-locked region
+ * @rdtgrp: resource group to which pseudo-lock region belongs
+ *
+ * Called when a resource group in the pseudo-locksetup mode receives a
+ * valid schemata that should be pseudo-locked. Since the resource group is
+ * in pseudo-locksetup mode the &struct pseudo_lock_region has already been
+ * allocated and initialized with the essential information. If a failure
+ * occurs the resource group remains in the pseudo-locksetup mode with the
+ * &struct pseudo_lock_region associated with it, but cleared from all
+ * information and ready for the user to re-attempt pseudo-locking by
+ * writing the schemata again.
+ *
+ * Return: 0 if the pseudo-locked region was successfully pseudo-locked, <0
+ * on failure. Descriptive error will be written to last_cmd_status buffer.
+ */
+int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
+{
+	struct pseudo_lock_region *plr = rdtgrp->plr;
+	struct task_struct *thread;
+	unsigned int new_minor;
+	struct device *dev;
+	int ret;
+
+	ret = pseudo_lock_region_alloc(plr);
+	if (ret < 0)
+		return ret;
+
+	ret = pseudo_lock_cstates_constrain(plr);
+	if (ret < 0) {
+		ret = -EINVAL;
+		goto out_region;
+	}
+
+	plr->thread_done = 0;
+
+	thread = kthread_create_on_node(pseudo_lock_fn, rdtgrp,
+					cpu_to_node(plr->cpu),
+					"pseudo_lock/%u", plr->cpu);
+	if (IS_ERR(thread)) {
+		ret = PTR_ERR(thread);
+		rdt_last_cmd_printf("Locking thread returned error %d\n", ret);
+		goto out_cstates;
+	}
+
+	kthread_bind(thread, plr->cpu);
+	wake_up_process(thread);
+
+	ret = wait_event_interruptible(plr->lock_thread_wq,
+				       plr->thread_done == 1);
+	if (ret < 0) {
+		/*
+		 * If the thread does not get on the CPU for whatever
+		 * reason and the process which sets up the region is
+		 * interrupted then this will leave the thread in runnable
+		 * state and once it gets on the CPU it will dereference
+		 * the cleared, but not freed, plr struct resulting in an
+		 * empty pseudo-locking loop.
+		 */
+		rdt_last_cmd_puts("Locking thread interrupted\n");
+		goto out_cstates;
+	}
+
+	ret = pseudo_lock_minor_get(&new_minor);
+	if (ret < 0) {
+		rdt_last_cmd_puts("Unable to obtain a new minor number\n");
+		goto out_cstates;
+	}
+
+	/*
+	 * Unlock access but do not release the reference. The
+	 * pseudo-locked region will still be here on return.
+	 *
+	 * The mutex has to be released temporarily to avoid a potential
+	 * deadlock with the mm->mmap_lock which is obtained in the
+	 * device_create() and debugfs_create_dir() callpath below as well as
+	 * before the mmap() callback is called.
+	 */
+	mutex_unlock(&rdtgroup_mutex);
+
+	if (!IS_ERR_OR_NULL(debugfs_resctrl)) {
+		plr->debugfs_dir = debugfs_create_dir(rdtgrp->kn->name,
+						      debugfs_resctrl);
+		if (!IS_ERR_OR_NULL(plr->debugfs_dir))
+			debugfs_create_file("pseudo_lock_measure", 0200,
+					    plr->debugfs_dir, rdtgrp,
+					    &pseudo_measure_fops);
+	}
+
+	dev = device_create(&pseudo_lock_class, NULL,
+			    MKDEV(pseudo_lock_major, new_minor),
+			    rdtgrp, "%s", rdtgrp->kn->name);
+
+	mutex_lock(&rdtgroup_mutex);
+
+	if (IS_ERR(dev)) {
+		ret = PTR_ERR(dev);
+		rdt_last_cmd_printf("Failed to create character device: %d\n",
+				    ret);
+		goto out_debugfs;
+	}
+
+	/* We released the mutex - check if group was removed while we did so */
+	if (rdtgrp->flags & RDT_DELETED) {
+		ret = -ENODEV;
+		goto out_device;
+	}
+
+	plr->minor = new_minor;
+
+	rdtgrp->mode = RDT_MODE_PSEUDO_LOCKED;
+	closid_free(rdtgrp->closid);
+	rdtgroup_kn_mode_restore(rdtgrp, "cpus", 0444);
+	rdtgroup_kn_mode_restore(rdtgrp, "cpus_list", 0444);
+
+	ret = 0;
+	goto out;
+
+out_device:
+	device_destroy(&pseudo_lock_class, MKDEV(pseudo_lock_major, new_minor));
+out_debugfs:
+	debugfs_remove_recursive(plr->debugfs_dir);
+	pseudo_lock_minor_release(new_minor);
+out_cstates:
+	pseudo_lock_cstates_relax(plr);
+out_region:
+	pseudo_lock_region_clear(plr);
+out:
+	return ret;
+}
+
+/**
+ * rdtgroup_pseudo_lock_remove - Remove a pseudo-locked region
+ * @rdtgrp: resource group to which the pseudo-locked region belongs
+ *
+ * The removal of a pseudo-locked region can be initiated when the resource
+ * group is removed from user space via a "rmdir" from userspace or the
+ * unmount of the resctrl filesystem. On removal the resource group does
+ * not go back to pseudo-locksetup mode before it is removed, instead it is
+ * removed directly. There is thus asymmetry with the creation where the
+ * &struct pseudo_lock_region is removed here while it was not created in
+ * rdtgroup_pseudo_lock_create().
+ *
+ * Return: void
+ */
+void rdtgroup_pseudo_lock_remove(struct rdtgroup *rdtgrp)
+{
+	struct pseudo_lock_region *plr = rdtgrp->plr;
+
+	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
+		/*
+		 * Default group cannot be a pseudo-locked region so we can
+		 * free closid here.
+		 */
+		closid_free(rdtgrp->closid);
+		goto free;
+	}
+
+	pseudo_lock_cstates_relax(plr);
+	debugfs_remove_recursive(rdtgrp->plr->debugfs_dir);
+	device_destroy(&pseudo_lock_class, MKDEV(pseudo_lock_major, plr->minor));
+	pseudo_lock_minor_release(plr->minor);
+
+free:
+	pseudo_lock_free(rdtgrp);
+}
+
+static int pseudo_lock_dev_open(struct inode *inode, struct file *filp)
+{
+	struct rdtgroup *rdtgrp;
+
+	mutex_lock(&rdtgroup_mutex);
+
+	rdtgrp = region_find_by_minor(iminor(inode));
+	if (!rdtgrp) {
+		mutex_unlock(&rdtgroup_mutex);
+		return -ENODEV;
+	}
+
+	filp->private_data = rdtgrp;
+	atomic_inc(&rdtgrp->waitcount);
+	/* Perform a non-seekable open - llseek is not supported */
+	filp->f_mode &= ~(FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE);
+
+	mutex_unlock(&rdtgroup_mutex);
+
+	return 0;
+}
+
+static int pseudo_lock_dev_release(struct inode *inode, struct file *filp)
+{
+	struct rdtgroup *rdtgrp;
+
+	mutex_lock(&rdtgroup_mutex);
+	rdtgrp = filp->private_data;
+	WARN_ON(!rdtgrp);
+	if (!rdtgrp) {
+		mutex_unlock(&rdtgroup_mutex);
+		return -ENODEV;
+	}
+	filp->private_data = NULL;
+	atomic_dec(&rdtgrp->waitcount);
+	mutex_unlock(&rdtgroup_mutex);
+	return 0;
+}
+
+static int pseudo_lock_dev_mremap(struct vm_area_struct *area)
+{
+	/* Not supported */
+	return -EINVAL;
+}
+
+static const struct vm_operations_struct pseudo_mmap_ops = {
+	.mremap = pseudo_lock_dev_mremap,
+};
+
+static int pseudo_lock_dev_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+	unsigned long vsize = vma->vm_end - vma->vm_start;
+	unsigned long off = vma->vm_pgoff << PAGE_SHIFT;
+	struct pseudo_lock_region *plr;
+	struct rdtgroup *rdtgrp;
+	unsigned long physical;
+	unsigned long psize;
+
+	mutex_lock(&rdtgroup_mutex);
+
+	rdtgrp = filp->private_data;
+	WARN_ON(!rdtgrp);
+	if (!rdtgrp) {
+		mutex_unlock(&rdtgroup_mutex);
+		return -ENODEV;
+	}
+
+	plr = rdtgrp->plr;
+
+	if (!plr->d) {
+		mutex_unlock(&rdtgroup_mutex);
+		return -ENODEV;
+	}
+
+	/*
+	 * Task is required to run with affinity to the cpus associated
+	 * with the pseudo-locked region. If this is not the case the task
+	 * may be scheduled elsewhere and invalidate entries in the
+	 * pseudo-locked region.
+	 */
+	if (!cpumask_subset(current->cpus_ptr, &plr->d->cpu_mask)) {
+		mutex_unlock(&rdtgroup_mutex);
+		return -EINVAL;
+	}
+
+	physical = __pa(plr->kmem) >> PAGE_SHIFT;
+	psize = plr->size - off;
+
+	if (off > plr->size) {
+		mutex_unlock(&rdtgroup_mutex);
+		return -ENOSPC;
+	}
+
+	/*
+	 * Ensure changes are carried directly to the memory being mapped,
+	 * do not allow copy-on-write mapping.
+	 */
+	if (!(vma->vm_flags & VM_SHARED)) {
+		mutex_unlock(&rdtgroup_mutex);
+		return -EINVAL;
+	}
+
+	if (vsize > psize) {
+		mutex_unlock(&rdtgroup_mutex);
+		return -ENOSPC;
+	}
+
+	memset(plr->kmem + off, 0, vsize);
+
+	if (remap_pfn_range(vma, vma->vm_start, physical + vma->vm_pgoff,
+			    vsize, vma->vm_page_prot)) {
+		mutex_unlock(&rdtgroup_mutex);
+		return -EAGAIN;
+	}
+	vma->vm_ops = &pseudo_mmap_ops;
+	mutex_unlock(&rdtgroup_mutex);
+	return 0;
+}
+
+static const struct file_operations pseudo_lock_dev_fops = {
+	.owner =	THIS_MODULE,
+	.llseek =	no_llseek,
+	.read =		NULL,
+	.write =	NULL,
+	.open =		pseudo_lock_dev_open,
+	.release =	pseudo_lock_dev_release,
+	.mmap =		pseudo_lock_dev_mmap,
+};
+
+int rdt_pseudo_lock_init(void)
+{
+	int ret;
+
+	ret = register_chrdev(0, "pseudo_lock", &pseudo_lock_dev_fops);
+	if (ret < 0)
+		return ret;
+
+	pseudo_lock_major = ret;
+
+	ret = class_register(&pseudo_lock_class);
+	if (ret) {
+		unregister_chrdev(pseudo_lock_major, "pseudo_lock");
+		return ret;
+	}
+
+	return 0;
+}
+
+void rdt_pseudo_lock_release(void)
+{
+	class_unregister(&pseudo_lock_class);
+	unregister_chrdev(pseudo_lock_major, "pseudo_lock");
+	pseudo_lock_major = 0;
+}
diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock_event.h b/arch/x86/kernel/cpu/resctrl/pseudo_lock_event.h
new file mode 100644
index 0000000000..428ebbd427
--- /dev/null
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock_event.h
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM resctrl
+
+#if !defined(_TRACE_PSEUDO_LOCK_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_PSEUDO_LOCK_H
+
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(pseudo_lock_mem_latency,
+	    TP_PROTO(u32 latency),
+	    TP_ARGS(latency),
+	    TP_STRUCT__entry(__field(u32, latency)),
+	    TP_fast_assign(__entry->latency = latency),
+	    TP_printk("latency=%u", __entry->latency)
+	   );
+
+TRACE_EVENT(pseudo_lock_l2,
+	    TP_PROTO(u64 l2_hits, u64 l2_miss),
+	    TP_ARGS(l2_hits, l2_miss),
+	    TP_STRUCT__entry(__field(u64, l2_hits)
+			     __field(u64, l2_miss)),
+	    TP_fast_assign(__entry->l2_hits = l2_hits;
+			   __entry->l2_miss = l2_miss;),
+	    TP_printk("hits=%llu miss=%llu",
+		      __entry->l2_hits, __entry->l2_miss));
+
+TRACE_EVENT(pseudo_lock_l3,
+	    TP_PROTO(u64 l3_hits, u64 l3_miss),
+	    TP_ARGS(l3_hits, l3_miss),
+	    TP_STRUCT__entry(__field(u64, l3_hits)
+			     __field(u64, l3_miss)),
+	    TP_fast_assign(__entry->l3_hits = l3_hits;
+			   __entry->l3_miss = l3_miss;),
+	    TP_printk("hits=%llu miss=%llu",
+		      __entry->l3_hits, __entry->l3_miss));
+
+#endif /* _TRACE_PSEUDO_LOCK_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE pseudo_lock_event
+#include <trace/define_trace.h>
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
new file mode 100644
index 0000000000..725344048f
--- /dev/null
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -0,0 +1,3874 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * User interface for Resource Allocation in Resource Director Technology(RDT)
+ *
+ * Copyright (C) 2016 Intel Corporation
+ *
+ * Author: Fenghua Yu <fenghua.yu@intel.com>
+ *
+ * More information about RDT be found in the Intel (R) x86 Architecture
+ * Software Developer Manual.
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/cacheinfo.h>
+#include <linux/cpu.h>
+#include <linux/debugfs.h>
+#include <linux/fs.h>
+#include <linux/fs_parser.h>
+#include <linux/sysfs.h>
+#include <linux/kernfs.h>
+#include <linux/seq_buf.h>
+#include <linux/seq_file.h>
+#include <linux/sched/signal.h>
+#include <linux/sched/task.h>
+#include <linux/slab.h>
+#include <linux/task_work.h>
+#include <linux/user_namespace.h>
+
+#include <uapi/linux/magic.h>
+
+#include <asm/resctrl.h>
+#include "internal.h"
+
+DEFINE_STATIC_KEY_FALSE(rdt_enable_key);
+DEFINE_STATIC_KEY_FALSE(rdt_mon_enable_key);
+DEFINE_STATIC_KEY_FALSE(rdt_alloc_enable_key);
+static struct kernfs_root *rdt_root;
+struct rdtgroup rdtgroup_default;
+LIST_HEAD(rdt_all_groups);
+
+/* list of entries for the schemata file */
+LIST_HEAD(resctrl_schema_all);
+
+/* Kernel fs node for "info" directory under root */
+static struct kernfs_node *kn_info;
+
+/* Kernel fs node for "mon_groups" directory under root */
+static struct kernfs_node *kn_mongrp;
+
+/* Kernel fs node for "mon_data" directory under root */
+static struct kernfs_node *kn_mondata;
+
+static struct seq_buf last_cmd_status;
+static char last_cmd_status_buf[512];
+
+struct dentry *debugfs_resctrl;
+
+void rdt_last_cmd_clear(void)
+{
+	lockdep_assert_held(&rdtgroup_mutex);
+	seq_buf_clear(&last_cmd_status);
+}
+
+void rdt_last_cmd_puts(const char *s)
+{
+	lockdep_assert_held(&rdtgroup_mutex);
+	seq_buf_puts(&last_cmd_status, s);
+}
+
+void rdt_last_cmd_printf(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	lockdep_assert_held(&rdtgroup_mutex);
+	seq_buf_vprintf(&last_cmd_status, fmt, ap);
+	va_end(ap);
+}
+
+void rdt_staged_configs_clear(void)
+{
+	struct rdt_resource *r;
+	struct rdt_domain *dom;
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	for_each_alloc_capable_rdt_resource(r) {
+		list_for_each_entry(dom, &r->domains, list)
+			memset(dom->staged_config, 0, sizeof(dom->staged_config));
+	}
+}
+
+/*
+ * Trivial allocator for CLOSIDs. Since h/w only supports a small number,
+ * we can keep a bitmap of free CLOSIDs in a single integer.
+ *
+ * Using a global CLOSID across all resources has some advantages and
+ * some drawbacks:
+ * + We can simply set "current->closid" to assign a task to a resource
+ *   group.
+ * + Context switch code can avoid extra memory references deciding which
+ *   CLOSID to load into the PQR_ASSOC MSR
+ * - We give up some options in configuring resource groups across multi-socket
+ *   systems.
+ * - Our choices on how to configure each resource become progressively more
+ *   limited as the number of resources grows.
+ */
+static int closid_free_map;
+static int closid_free_map_len;
+
+int closids_supported(void)
+{
+	return closid_free_map_len;
+}
+
+static void closid_init(void)
+{
+	struct resctrl_schema *s;
+	u32 rdt_min_closid = 32;
+
+	/* Compute rdt_min_closid across all resources */
+	list_for_each_entry(s, &resctrl_schema_all, list)
+		rdt_min_closid = min(rdt_min_closid, s->num_closid);
+
+	closid_free_map = BIT_MASK(rdt_min_closid) - 1;
+
+	/* CLOSID 0 is always reserved for the default group */
+	closid_free_map &= ~1;
+	closid_free_map_len = rdt_min_closid;
+}
+
+static int closid_alloc(void)
+{
+	u32 closid = ffs(closid_free_map);
+
+	if (closid == 0)
+		return -ENOSPC;
+	closid--;
+	closid_free_map &= ~(1 << closid);
+
+	return closid;
+}
+
+void closid_free(int closid)
+{
+	closid_free_map |= 1 << closid;
+}
+
+/**
+ * closid_allocated - test if provided closid is in use
+ * @closid: closid to be tested
+ *
+ * Return: true if @closid is currently associated with a resource group,
+ * false if @closid is free
+ */
+static bool closid_allocated(unsigned int closid)
+{
+	return (closid_free_map & (1 << closid)) == 0;
+}
+
+/**
+ * rdtgroup_mode_by_closid - Return mode of resource group with closid
+ * @closid: closid if the resource group
+ *
+ * Each resource group is associated with a @closid. Here the mode
+ * of a resource group can be queried by searching for it using its closid.
+ *
+ * Return: mode as &enum rdtgrp_mode of resource group with closid @closid
+ */
+enum rdtgrp_mode rdtgroup_mode_by_closid(int closid)
+{
+	struct rdtgroup *rdtgrp;
+
+	list_for_each_entry(rdtgrp, &rdt_all_groups, rdtgroup_list) {
+		if (rdtgrp->closid == closid)
+			return rdtgrp->mode;
+	}
+
+	return RDT_NUM_MODES;
+}
+
+static const char * const rdt_mode_str[] = {
+	[RDT_MODE_SHAREABLE]		= "shareable",
+	[RDT_MODE_EXCLUSIVE]		= "exclusive",
+	[RDT_MODE_PSEUDO_LOCKSETUP]	= "pseudo-locksetup",
+	[RDT_MODE_PSEUDO_LOCKED]	= "pseudo-locked",
+};
+
+/**
+ * rdtgroup_mode_str - Return the string representation of mode
+ * @mode: the resource group mode as &enum rdtgroup_mode
+ *
+ * Return: string representation of valid mode, "unknown" otherwise
+ */
+static const char *rdtgroup_mode_str(enum rdtgrp_mode mode)
+{
+	if (mode < RDT_MODE_SHAREABLE || mode >= RDT_NUM_MODES)
+		return "unknown";
+
+	return rdt_mode_str[mode];
+}
+
+/* set uid and gid of rdtgroup dirs and files to that of the creator */
+static int rdtgroup_kn_set_ugid(struct kernfs_node *kn)
+{
+	struct iattr iattr = { .ia_valid = ATTR_UID | ATTR_GID,
+				.ia_uid = current_fsuid(),
+				.ia_gid = current_fsgid(), };
+
+	if (uid_eq(iattr.ia_uid, GLOBAL_ROOT_UID) &&
+	    gid_eq(iattr.ia_gid, GLOBAL_ROOT_GID))
+		return 0;
+
+	return kernfs_setattr(kn, &iattr);
+}
+
+static int rdtgroup_add_file(struct kernfs_node *parent_kn, struct rftype *rft)
+{
+	struct kernfs_node *kn;
+	int ret;
+
+	kn = __kernfs_create_file(parent_kn, rft->name, rft->mode,
+				  GLOBAL_ROOT_UID, GLOBAL_ROOT_GID,
+				  0, rft->kf_ops, rft, NULL, NULL);
+	if (IS_ERR(kn))
+		return PTR_ERR(kn);
+
+	ret = rdtgroup_kn_set_ugid(kn);
+	if (ret) {
+		kernfs_remove(kn);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int rdtgroup_seqfile_show(struct seq_file *m, void *arg)
+{
+	struct kernfs_open_file *of = m->private;
+	struct rftype *rft = of->kn->priv;
+
+	if (rft->seq_show)
+		return rft->seq_show(of, m, arg);
+	return 0;
+}
+
+static ssize_t rdtgroup_file_write(struct kernfs_open_file *of, char *buf,
+				   size_t nbytes, loff_t off)
+{
+	struct rftype *rft = of->kn->priv;
+
+	if (rft->write)
+		return rft->write(of, buf, nbytes, off);
+
+	return -EINVAL;
+}
+
+static const struct kernfs_ops rdtgroup_kf_single_ops = {
+	.atomic_write_len	= PAGE_SIZE,
+	.write			= rdtgroup_file_write,
+	.seq_show		= rdtgroup_seqfile_show,
+};
+
+static const struct kernfs_ops kf_mondata_ops = {
+	.atomic_write_len	= PAGE_SIZE,
+	.seq_show		= rdtgroup_mondata_show,
+};
+
+static bool is_cpu_list(struct kernfs_open_file *of)
+{
+	struct rftype *rft = of->kn->priv;
+
+	return rft->flags & RFTYPE_FLAGS_CPUS_LIST;
+}
+
+static int rdtgroup_cpus_show(struct kernfs_open_file *of,
+			      struct seq_file *s, void *v)
+{
+	struct rdtgroup *rdtgrp;
+	struct cpumask *mask;
+	int ret = 0;
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+
+	if (rdtgrp) {
+		if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) {
+			if (!rdtgrp->plr->d) {
+				rdt_last_cmd_clear();
+				rdt_last_cmd_puts("Cache domain offline\n");
+				ret = -ENODEV;
+			} else {
+				mask = &rdtgrp->plr->d->cpu_mask;
+				seq_printf(s, is_cpu_list(of) ?
+					   "%*pbl\n" : "%*pb\n",
+					   cpumask_pr_args(mask));
+			}
+		} else {
+			seq_printf(s, is_cpu_list(of) ? "%*pbl\n" : "%*pb\n",
+				   cpumask_pr_args(&rdtgrp->cpu_mask));
+		}
+	} else {
+		ret = -ENOENT;
+	}
+	rdtgroup_kn_unlock(of->kn);
+
+	return ret;
+}
+
+/*
+ * This is safe against resctrl_sched_in() called from __switch_to()
+ * because __switch_to() is executed with interrupts disabled. A local call
+ * from update_closid_rmid() is protected against __switch_to() because
+ * preemption is disabled.
+ */
+static void update_cpu_closid_rmid(void *info)
+{
+	struct rdtgroup *r = info;
+
+	if (r) {
+		this_cpu_write(pqr_state.default_closid, r->closid);
+		this_cpu_write(pqr_state.default_rmid, r->mon.rmid);
+	}
+
+	/*
+	 * We cannot unconditionally write the MSR because the current
+	 * executing task might have its own closid selected. Just reuse
+	 * the context switch code.
+	 */
+	resctrl_sched_in(current);
+}
+
+/*
+ * Update the PGR_ASSOC MSR on all cpus in @cpu_mask,
+ *
+ * Per task closids/rmids must have been set up before calling this function.
+ */
+static void
+update_closid_rmid(const struct cpumask *cpu_mask, struct rdtgroup *r)
+{
+	on_each_cpu_mask(cpu_mask, update_cpu_closid_rmid, r, 1);
+}
+
+static int cpus_mon_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask,
+			  cpumask_var_t tmpmask)
+{
+	struct rdtgroup *prgrp = rdtgrp->mon.parent, *crgrp;
+	struct list_head *head;
+
+	/* Check whether cpus belong to parent ctrl group */
+	cpumask_andnot(tmpmask, newmask, &prgrp->cpu_mask);
+	if (!cpumask_empty(tmpmask)) {
+		rdt_last_cmd_puts("Can only add CPUs to mongroup that belong to parent\n");
+		return -EINVAL;
+	}
+
+	/* Check whether cpus are dropped from this group */
+	cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask);
+	if (!cpumask_empty(tmpmask)) {
+		/* Give any dropped cpus to parent rdtgroup */
+		cpumask_or(&prgrp->cpu_mask, &prgrp->cpu_mask, tmpmask);
+		update_closid_rmid(tmpmask, prgrp);
+	}
+
+	/*
+	 * If we added cpus, remove them from previous group that owned them
+	 * and update per-cpu rmid
+	 */
+	cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask);
+	if (!cpumask_empty(tmpmask)) {
+		head = &prgrp->mon.crdtgrp_list;
+		list_for_each_entry(crgrp, head, mon.crdtgrp_list) {
+			if (crgrp == rdtgrp)
+				continue;
+			cpumask_andnot(&crgrp->cpu_mask, &crgrp->cpu_mask,
+				       tmpmask);
+		}
+		update_closid_rmid(tmpmask, rdtgrp);
+	}
+
+	/* Done pushing/pulling - update this group with new mask */
+	cpumask_copy(&rdtgrp->cpu_mask, newmask);
+
+	return 0;
+}
+
+static void cpumask_rdtgrp_clear(struct rdtgroup *r, struct cpumask *m)
+{
+	struct rdtgroup *crgrp;
+
+	cpumask_andnot(&r->cpu_mask, &r->cpu_mask, m);
+	/* update the child mon group masks as well*/
+	list_for_each_entry(crgrp, &r->mon.crdtgrp_list, mon.crdtgrp_list)
+		cpumask_and(&crgrp->cpu_mask, &r->cpu_mask, &crgrp->cpu_mask);
+}
+
+static int cpus_ctrl_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask,
+			   cpumask_var_t tmpmask, cpumask_var_t tmpmask1)
+{
+	struct rdtgroup *r, *crgrp;
+	struct list_head *head;
+
+	/* Check whether cpus are dropped from this group */
+	cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask);
+	if (!cpumask_empty(tmpmask)) {
+		/* Can't drop from default group */
+		if (rdtgrp == &rdtgroup_default) {
+			rdt_last_cmd_puts("Can't drop CPUs from default group\n");
+			return -EINVAL;
+		}
+
+		/* Give any dropped cpus to rdtgroup_default */
+		cpumask_or(&rdtgroup_default.cpu_mask,
+			   &rdtgroup_default.cpu_mask, tmpmask);
+		update_closid_rmid(tmpmask, &rdtgroup_default);
+	}
+
+	/*
+	 * If we added cpus, remove them from previous group and
+	 * the prev group's child groups that owned them
+	 * and update per-cpu closid/rmid.
+	 */
+	cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask);
+	if (!cpumask_empty(tmpmask)) {
+		list_for_each_entry(r, &rdt_all_groups, rdtgroup_list) {
+			if (r == rdtgrp)
+				continue;
+			cpumask_and(tmpmask1, &r->cpu_mask, tmpmask);
+			if (!cpumask_empty(tmpmask1))
+				cpumask_rdtgrp_clear(r, tmpmask1);
+		}
+		update_closid_rmid(tmpmask, rdtgrp);
+	}
+
+	/* Done pushing/pulling - update this group with new mask */
+	cpumask_copy(&rdtgrp->cpu_mask, newmask);
+
+	/*
+	 * Clear child mon group masks since there is a new parent mask
+	 * now and update the rmid for the cpus the child lost.
+	 */
+	head = &rdtgrp->mon.crdtgrp_list;
+	list_for_each_entry(crgrp, head, mon.crdtgrp_list) {
+		cpumask_and(tmpmask, &rdtgrp->cpu_mask, &crgrp->cpu_mask);
+		update_closid_rmid(tmpmask, rdtgrp);
+		cpumask_clear(&crgrp->cpu_mask);
+	}
+
+	return 0;
+}
+
+static ssize_t rdtgroup_cpus_write(struct kernfs_open_file *of,
+				   char *buf, size_t nbytes, loff_t off)
+{
+	cpumask_var_t tmpmask, newmask, tmpmask1;
+	struct rdtgroup *rdtgrp;
+	int ret;
+
+	if (!buf)
+		return -EINVAL;
+
+	if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL))
+		return -ENOMEM;
+	if (!zalloc_cpumask_var(&newmask, GFP_KERNEL)) {
+		free_cpumask_var(tmpmask);
+		return -ENOMEM;
+	}
+	if (!zalloc_cpumask_var(&tmpmask1, GFP_KERNEL)) {
+		free_cpumask_var(tmpmask);
+		free_cpumask_var(newmask);
+		return -ENOMEM;
+	}
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (!rdtgrp) {
+		ret = -ENOENT;
+		goto unlock;
+	}
+
+	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED ||
+	    rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
+		ret = -EINVAL;
+		rdt_last_cmd_puts("Pseudo-locking in progress\n");
+		goto unlock;
+	}
+
+	if (is_cpu_list(of))
+		ret = cpulist_parse(buf, newmask);
+	else
+		ret = cpumask_parse(buf, newmask);
+
+	if (ret) {
+		rdt_last_cmd_puts("Bad CPU list/mask\n");
+		goto unlock;
+	}
+
+	/* check that user didn't specify any offline cpus */
+	cpumask_andnot(tmpmask, newmask, cpu_online_mask);
+	if (!cpumask_empty(tmpmask)) {
+		ret = -EINVAL;
+		rdt_last_cmd_puts("Can only assign online CPUs\n");
+		goto unlock;
+	}
+
+	if (rdtgrp->type == RDTCTRL_GROUP)
+		ret = cpus_ctrl_write(rdtgrp, newmask, tmpmask, tmpmask1);
+	else if (rdtgrp->type == RDTMON_GROUP)
+		ret = cpus_mon_write(rdtgrp, newmask, tmpmask);
+	else
+		ret = -EINVAL;
+
+unlock:
+	rdtgroup_kn_unlock(of->kn);
+	free_cpumask_var(tmpmask);
+	free_cpumask_var(newmask);
+	free_cpumask_var(tmpmask1);
+
+	return ret ?: nbytes;
+}
+
+/**
+ * rdtgroup_remove - the helper to remove resource group safely
+ * @rdtgrp: resource group to remove
+ *
+ * On resource group creation via a mkdir, an extra kernfs_node reference is
+ * taken to ensure that the rdtgroup structure remains accessible for the
+ * rdtgroup_kn_unlock() calls where it is removed.
+ *
+ * Drop the extra reference here, then free the rdtgroup structure.
+ *
+ * Return: void
+ */
+static void rdtgroup_remove(struct rdtgroup *rdtgrp)
+{
+	kernfs_put(rdtgrp->kn);
+	kfree(rdtgrp);
+}
+
+static void _update_task_closid_rmid(void *task)
+{
+	/*
+	 * If the task is still current on this CPU, update PQR_ASSOC MSR.
+	 * Otherwise, the MSR is updated when the task is scheduled in.
+	 */
+	if (task == current)
+		resctrl_sched_in(task);
+}
+
+static void update_task_closid_rmid(struct task_struct *t)
+{
+	if (IS_ENABLED(CONFIG_SMP) && task_curr(t))
+		smp_call_function_single(task_cpu(t), _update_task_closid_rmid, t, 1);
+	else
+		_update_task_closid_rmid(t);
+}
+
+static int __rdtgroup_move_task(struct task_struct *tsk,
+				struct rdtgroup *rdtgrp)
+{
+	/* If the task is already in rdtgrp, no need to move the task. */
+	if ((rdtgrp->type == RDTCTRL_GROUP && tsk->closid == rdtgrp->closid &&
+	     tsk->rmid == rdtgrp->mon.rmid) ||
+	    (rdtgrp->type == RDTMON_GROUP && tsk->rmid == rdtgrp->mon.rmid &&
+	     tsk->closid == rdtgrp->mon.parent->closid))
+		return 0;
+
+	/*
+	 * Set the task's closid/rmid before the PQR_ASSOC MSR can be
+	 * updated by them.
+	 *
+	 * For ctrl_mon groups, move both closid and rmid.
+	 * For monitor groups, can move the tasks only from
+	 * their parent CTRL group.
+	 */
+
+	if (rdtgrp->type == RDTCTRL_GROUP) {
+		WRITE_ONCE(tsk->closid, rdtgrp->closid);
+		WRITE_ONCE(tsk->rmid, rdtgrp->mon.rmid);
+	} else if (rdtgrp->type == RDTMON_GROUP) {
+		if (rdtgrp->mon.parent->closid == tsk->closid) {
+			WRITE_ONCE(tsk->rmid, rdtgrp->mon.rmid);
+		} else {
+			rdt_last_cmd_puts("Can't move task to different control group\n");
+			return -EINVAL;
+		}
+	}
+
+	/*
+	 * Ensure the task's closid and rmid are written before determining if
+	 * the task is current that will decide if it will be interrupted.
+	 * This pairs with the full barrier between the rq->curr update and
+	 * resctrl_sched_in() during context switch.
+	 */
+	smp_mb();
+
+	/*
+	 * By now, the task's closid and rmid are set. If the task is current
+	 * on a CPU, the PQR_ASSOC MSR needs to be updated to make the resource
+	 * group go into effect. If the task is not current, the MSR will be
+	 * updated when the task is scheduled in.
+	 */
+	update_task_closid_rmid(tsk);
+
+	return 0;
+}
+
+static bool is_closid_match(struct task_struct *t, struct rdtgroup *r)
+{
+	return (rdt_alloc_capable &&
+	       (r->type == RDTCTRL_GROUP) && (t->closid == r->closid));
+}
+
+static bool is_rmid_match(struct task_struct *t, struct rdtgroup *r)
+{
+	return (rdt_mon_capable &&
+	       (r->type == RDTMON_GROUP) && (t->rmid == r->mon.rmid));
+}
+
+/**
+ * rdtgroup_tasks_assigned - Test if tasks have been assigned to resource group
+ * @r: Resource group
+ *
+ * Return: 1 if tasks have been assigned to @r, 0 otherwise
+ */
+int rdtgroup_tasks_assigned(struct rdtgroup *r)
+{
+	struct task_struct *p, *t;
+	int ret = 0;
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	rcu_read_lock();
+	for_each_process_thread(p, t) {
+		if (is_closid_match(t, r) || is_rmid_match(t, r)) {
+			ret = 1;
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	return ret;
+}
+
+static int rdtgroup_task_write_permission(struct task_struct *task,
+					  struct kernfs_open_file *of)
+{
+	const struct cred *tcred = get_task_cred(task);
+	const struct cred *cred = current_cred();
+	int ret = 0;
+
+	/*
+	 * Even if we're attaching all tasks in the thread group, we only
+	 * need to check permissions on one of them.
+	 */
+	if (!uid_eq(cred->euid, GLOBAL_ROOT_UID) &&
+	    !uid_eq(cred->euid, tcred->uid) &&
+	    !uid_eq(cred->euid, tcred->suid)) {
+		rdt_last_cmd_printf("No permission to move task %d\n", task->pid);
+		ret = -EPERM;
+	}
+
+	put_cred(tcred);
+	return ret;
+}
+
+static int rdtgroup_move_task(pid_t pid, struct rdtgroup *rdtgrp,
+			      struct kernfs_open_file *of)
+{
+	struct task_struct *tsk;
+	int ret;
+
+	rcu_read_lock();
+	if (pid) {
+		tsk = find_task_by_vpid(pid);
+		if (!tsk) {
+			rcu_read_unlock();
+			rdt_last_cmd_printf("No task %d\n", pid);
+			return -ESRCH;
+		}
+	} else {
+		tsk = current;
+	}
+
+	get_task_struct(tsk);
+	rcu_read_unlock();
+
+	ret = rdtgroup_task_write_permission(tsk, of);
+	if (!ret)
+		ret = __rdtgroup_move_task(tsk, rdtgrp);
+
+	put_task_struct(tsk);
+	return ret;
+}
+
+static ssize_t rdtgroup_tasks_write(struct kernfs_open_file *of,
+				    char *buf, size_t nbytes, loff_t off)
+{
+	struct rdtgroup *rdtgrp;
+	int ret = 0;
+	pid_t pid;
+
+	if (kstrtoint(strstrip(buf), 0, &pid) || pid < 0)
+		return -EINVAL;
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (!rdtgrp) {
+		rdtgroup_kn_unlock(of->kn);
+		return -ENOENT;
+	}
+	rdt_last_cmd_clear();
+
+	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED ||
+	    rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
+		ret = -EINVAL;
+		rdt_last_cmd_puts("Pseudo-locking in progress\n");
+		goto unlock;
+	}
+
+	ret = rdtgroup_move_task(pid, rdtgrp, of);
+
+unlock:
+	rdtgroup_kn_unlock(of->kn);
+
+	return ret ?: nbytes;
+}
+
+static void show_rdt_tasks(struct rdtgroup *r, struct seq_file *s)
+{
+	struct task_struct *p, *t;
+	pid_t pid;
+
+	rcu_read_lock();
+	for_each_process_thread(p, t) {
+		if (is_closid_match(t, r) || is_rmid_match(t, r)) {
+			pid = task_pid_vnr(t);
+			if (pid)
+				seq_printf(s, "%d\n", pid);
+		}
+	}
+	rcu_read_unlock();
+}
+
+static int rdtgroup_tasks_show(struct kernfs_open_file *of,
+			       struct seq_file *s, void *v)
+{
+	struct rdtgroup *rdtgrp;
+	int ret = 0;
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (rdtgrp)
+		show_rdt_tasks(rdtgrp, s);
+	else
+		ret = -ENOENT;
+	rdtgroup_kn_unlock(of->kn);
+
+	return ret;
+}
+
+#ifdef CONFIG_PROC_CPU_RESCTRL
+
+/*
+ * A task can only be part of one resctrl control group and of one monitor
+ * group which is associated to that control group.
+ *
+ * 1)   res:
+ *      mon:
+ *
+ *    resctrl is not available.
+ *
+ * 2)   res:/
+ *      mon:
+ *
+ *    Task is part of the root resctrl control group, and it is not associated
+ *    to any monitor group.
+ *
+ * 3)  res:/
+ *     mon:mon0
+ *
+ *    Task is part of the root resctrl control group and monitor group mon0.
+ *
+ * 4)  res:group0
+ *     mon:
+ *
+ *    Task is part of resctrl control group group0, and it is not associated
+ *    to any monitor group.
+ *
+ * 5) res:group0
+ *    mon:mon1
+ *
+ *    Task is part of resctrl control group group0 and monitor group mon1.
+ */
+int proc_resctrl_show(struct seq_file *s, struct pid_namespace *ns,
+		      struct pid *pid, struct task_struct *tsk)
+{
+	struct rdtgroup *rdtg;
+	int ret = 0;
+
+	mutex_lock(&rdtgroup_mutex);
+
+	/* Return empty if resctrl has not been mounted. */
+	if (!static_branch_unlikely(&rdt_enable_key)) {
+		seq_puts(s, "res:\nmon:\n");
+		goto unlock;
+	}
+
+	list_for_each_entry(rdtg, &rdt_all_groups, rdtgroup_list) {
+		struct rdtgroup *crg;
+
+		/*
+		 * Task information is only relevant for shareable
+		 * and exclusive groups.
+		 */
+		if (rdtg->mode != RDT_MODE_SHAREABLE &&
+		    rdtg->mode != RDT_MODE_EXCLUSIVE)
+			continue;
+
+		if (rdtg->closid != tsk->closid)
+			continue;
+
+		seq_printf(s, "res:%s%s\n", (rdtg == &rdtgroup_default) ? "/" : "",
+			   rdtg->kn->name);
+		seq_puts(s, "mon:");
+		list_for_each_entry(crg, &rdtg->mon.crdtgrp_list,
+				    mon.crdtgrp_list) {
+			if (tsk->rmid != crg->mon.rmid)
+				continue;
+			seq_printf(s, "%s", crg->kn->name);
+			break;
+		}
+		seq_putc(s, '\n');
+		goto unlock;
+	}
+	/*
+	 * The above search should succeed. Otherwise return
+	 * with an error.
+	 */
+	ret = -ENOENT;
+unlock:
+	mutex_unlock(&rdtgroup_mutex);
+
+	return ret;
+}
+#endif
+
+static int rdt_last_cmd_status_show(struct kernfs_open_file *of,
+				    struct seq_file *seq, void *v)
+{
+	int len;
+
+	mutex_lock(&rdtgroup_mutex);
+	len = seq_buf_used(&last_cmd_status);
+	if (len)
+		seq_printf(seq, "%.*s", len, last_cmd_status_buf);
+	else
+		seq_puts(seq, "ok\n");
+	mutex_unlock(&rdtgroup_mutex);
+	return 0;
+}
+
+static int rdt_num_closids_show(struct kernfs_open_file *of,
+				struct seq_file *seq, void *v)
+{
+	struct resctrl_schema *s = of->kn->parent->priv;
+
+	seq_printf(seq, "%u\n", s->num_closid);
+	return 0;
+}
+
+static int rdt_default_ctrl_show(struct kernfs_open_file *of,
+			     struct seq_file *seq, void *v)
+{
+	struct resctrl_schema *s = of->kn->parent->priv;
+	struct rdt_resource *r = s->res;
+
+	seq_printf(seq, "%x\n", r->default_ctrl);
+	return 0;
+}
+
+static int rdt_min_cbm_bits_show(struct kernfs_open_file *of,
+			     struct seq_file *seq, void *v)
+{
+	struct resctrl_schema *s = of->kn->parent->priv;
+	struct rdt_resource *r = s->res;
+
+	seq_printf(seq, "%u\n", r->cache.min_cbm_bits);
+	return 0;
+}
+
+static int rdt_shareable_bits_show(struct kernfs_open_file *of,
+				   struct seq_file *seq, void *v)
+{
+	struct resctrl_schema *s = of->kn->parent->priv;
+	struct rdt_resource *r = s->res;
+
+	seq_printf(seq, "%x\n", r->cache.shareable_bits);
+	return 0;
+}
+
+/**
+ * rdt_bit_usage_show - Display current usage of resources
+ *
+ * A domain is a shared resource that can now be allocated differently. Here
+ * we display the current regions of the domain as an annotated bitmask.
+ * For each domain of this resource its allocation bitmask
+ * is annotated as below to indicate the current usage of the corresponding bit:
+ *   0 - currently unused
+ *   X - currently available for sharing and used by software and hardware
+ *   H - currently used by hardware only but available for software use
+ *   S - currently used and shareable by software only
+ *   E - currently used exclusively by one resource group
+ *   P - currently pseudo-locked by one resource group
+ */
+static int rdt_bit_usage_show(struct kernfs_open_file *of,
+			      struct seq_file *seq, void *v)
+{
+	struct resctrl_schema *s = of->kn->parent->priv;
+	/*
+	 * Use unsigned long even though only 32 bits are used to ensure
+	 * test_bit() is used safely.
+	 */
+	unsigned long sw_shareable = 0, hw_shareable = 0;
+	unsigned long exclusive = 0, pseudo_locked = 0;
+	struct rdt_resource *r = s->res;
+	struct rdt_domain *dom;
+	int i, hwb, swb, excl, psl;
+	enum rdtgrp_mode mode;
+	bool sep = false;
+	u32 ctrl_val;
+
+	mutex_lock(&rdtgroup_mutex);
+	hw_shareable = r->cache.shareable_bits;
+	list_for_each_entry(dom, &r->domains, list) {
+		if (sep)
+			seq_putc(seq, ';');
+		sw_shareable = 0;
+		exclusive = 0;
+		seq_printf(seq, "%d=", dom->id);
+		for (i = 0; i < closids_supported(); i++) {
+			if (!closid_allocated(i))
+				continue;
+			ctrl_val = resctrl_arch_get_config(r, dom, i,
+							   s->conf_type);
+			mode = rdtgroup_mode_by_closid(i);
+			switch (mode) {
+			case RDT_MODE_SHAREABLE:
+				sw_shareable |= ctrl_val;
+				break;
+			case RDT_MODE_EXCLUSIVE:
+				exclusive |= ctrl_val;
+				break;
+			case RDT_MODE_PSEUDO_LOCKSETUP:
+			/*
+			 * RDT_MODE_PSEUDO_LOCKSETUP is possible
+			 * here but not included since the CBM
+			 * associated with this CLOSID in this mode
+			 * is not initialized and no task or cpu can be
+			 * assigned this CLOSID.
+			 */
+				break;
+			case RDT_MODE_PSEUDO_LOCKED:
+			case RDT_NUM_MODES:
+				WARN(1,
+				     "invalid mode for closid %d\n", i);
+				break;
+			}
+		}
+		for (i = r->cache.cbm_len - 1; i >= 0; i--) {
+			pseudo_locked = dom->plr ? dom->plr->cbm : 0;
+			hwb = test_bit(i, &hw_shareable);
+			swb = test_bit(i, &sw_shareable);
+			excl = test_bit(i, &exclusive);
+			psl = test_bit(i, &pseudo_locked);
+			if (hwb && swb)
+				seq_putc(seq, 'X');
+			else if (hwb && !swb)
+				seq_putc(seq, 'H');
+			else if (!hwb && swb)
+				seq_putc(seq, 'S');
+			else if (excl)
+				seq_putc(seq, 'E');
+			else if (psl)
+				seq_putc(seq, 'P');
+			else /* Unused bits remain */
+				seq_putc(seq, '0');
+		}
+		sep = true;
+	}
+	seq_putc(seq, '\n');
+	mutex_unlock(&rdtgroup_mutex);
+	return 0;
+}
+
+static int rdt_min_bw_show(struct kernfs_open_file *of,
+			     struct seq_file *seq, void *v)
+{
+	struct resctrl_schema *s = of->kn->parent->priv;
+	struct rdt_resource *r = s->res;
+
+	seq_printf(seq, "%u\n", r->membw.min_bw);
+	return 0;
+}
+
+static int rdt_num_rmids_show(struct kernfs_open_file *of,
+			      struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	seq_printf(seq, "%d\n", r->num_rmid);
+
+	return 0;
+}
+
+static int rdt_mon_features_show(struct kernfs_open_file *of,
+				 struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+	struct mon_evt *mevt;
+
+	list_for_each_entry(mevt, &r->evt_list, list) {
+		seq_printf(seq, "%s\n", mevt->name);
+		if (mevt->configurable)
+			seq_printf(seq, "%s_config\n", mevt->name);
+	}
+
+	return 0;
+}
+
+static int rdt_bw_gran_show(struct kernfs_open_file *of,
+			     struct seq_file *seq, void *v)
+{
+	struct resctrl_schema *s = of->kn->parent->priv;
+	struct rdt_resource *r = s->res;
+
+	seq_printf(seq, "%u\n", r->membw.bw_gran);
+	return 0;
+}
+
+static int rdt_delay_linear_show(struct kernfs_open_file *of,
+			     struct seq_file *seq, void *v)
+{
+	struct resctrl_schema *s = of->kn->parent->priv;
+	struct rdt_resource *r = s->res;
+
+	seq_printf(seq, "%u\n", r->membw.delay_linear);
+	return 0;
+}
+
+static int max_threshold_occ_show(struct kernfs_open_file *of,
+				  struct seq_file *seq, void *v)
+{
+	seq_printf(seq, "%u\n", resctrl_rmid_realloc_threshold);
+
+	return 0;
+}
+
+static int rdt_thread_throttle_mode_show(struct kernfs_open_file *of,
+					 struct seq_file *seq, void *v)
+{
+	struct resctrl_schema *s = of->kn->parent->priv;
+	struct rdt_resource *r = s->res;
+
+	if (r->membw.throttle_mode == THREAD_THROTTLE_PER_THREAD)
+		seq_puts(seq, "per-thread\n");
+	else
+		seq_puts(seq, "max\n");
+
+	return 0;
+}
+
+static ssize_t max_threshold_occ_write(struct kernfs_open_file *of,
+				       char *buf, size_t nbytes, loff_t off)
+{
+	unsigned int bytes;
+	int ret;
+
+	ret = kstrtouint(buf, 0, &bytes);
+	if (ret)
+		return ret;
+
+	if (bytes > resctrl_rmid_realloc_limit)
+		return -EINVAL;
+
+	resctrl_rmid_realloc_threshold = resctrl_arch_round_mon_val(bytes);
+
+	return nbytes;
+}
+
+/*
+ * rdtgroup_mode_show - Display mode of this resource group
+ */
+static int rdtgroup_mode_show(struct kernfs_open_file *of,
+			      struct seq_file *s, void *v)
+{
+	struct rdtgroup *rdtgrp;
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (!rdtgrp) {
+		rdtgroup_kn_unlock(of->kn);
+		return -ENOENT;
+	}
+
+	seq_printf(s, "%s\n", rdtgroup_mode_str(rdtgrp->mode));
+
+	rdtgroup_kn_unlock(of->kn);
+	return 0;
+}
+
+static enum resctrl_conf_type resctrl_peer_type(enum resctrl_conf_type my_type)
+{
+	switch (my_type) {
+	case CDP_CODE:
+		return CDP_DATA;
+	case CDP_DATA:
+		return CDP_CODE;
+	default:
+	case CDP_NONE:
+		return CDP_NONE;
+	}
+}
+
+/**
+ * __rdtgroup_cbm_overlaps - Does CBM for intended closid overlap with other
+ * @r: Resource to which domain instance @d belongs.
+ * @d: The domain instance for which @closid is being tested.
+ * @cbm: Capacity bitmask being tested.
+ * @closid: Intended closid for @cbm.
+ * @exclusive: Only check if overlaps with exclusive resource groups
+ *
+ * Checks if provided @cbm intended to be used for @closid on domain
+ * @d overlaps with any other closids or other hardware usage associated
+ * with this domain. If @exclusive is true then only overlaps with
+ * resource groups in exclusive mode will be considered. If @exclusive
+ * is false then overlaps with any resource group or hardware entities
+ * will be considered.
+ *
+ * @cbm is unsigned long, even if only 32 bits are used, to make the
+ * bitmap functions work correctly.
+ *
+ * Return: false if CBM does not overlap, true if it does.
+ */
+static bool __rdtgroup_cbm_overlaps(struct rdt_resource *r, struct rdt_domain *d,
+				    unsigned long cbm, int closid,
+				    enum resctrl_conf_type type, bool exclusive)
+{
+	enum rdtgrp_mode mode;
+	unsigned long ctrl_b;
+	int i;
+
+	/* Check for any overlap with regions used by hardware directly */
+	if (!exclusive) {
+		ctrl_b = r->cache.shareable_bits;
+		if (bitmap_intersects(&cbm, &ctrl_b, r->cache.cbm_len))
+			return true;
+	}
+
+	/* Check for overlap with other resource groups */
+	for (i = 0; i < closids_supported(); i++) {
+		ctrl_b = resctrl_arch_get_config(r, d, i, type);
+		mode = rdtgroup_mode_by_closid(i);
+		if (closid_allocated(i) && i != closid &&
+		    mode != RDT_MODE_PSEUDO_LOCKSETUP) {
+			if (bitmap_intersects(&cbm, &ctrl_b, r->cache.cbm_len)) {
+				if (exclusive) {
+					if (mode == RDT_MODE_EXCLUSIVE)
+						return true;
+					continue;
+				}
+				return true;
+			}
+		}
+	}
+
+	return false;
+}
+
+/**
+ * rdtgroup_cbm_overlaps - Does CBM overlap with other use of hardware
+ * @s: Schema for the resource to which domain instance @d belongs.
+ * @d: The domain instance for which @closid is being tested.
+ * @cbm: Capacity bitmask being tested.
+ * @closid: Intended closid for @cbm.
+ * @exclusive: Only check if overlaps with exclusive resource groups
+ *
+ * Resources that can be allocated using a CBM can use the CBM to control
+ * the overlap of these allocations. rdtgroup_cmb_overlaps() is the test
+ * for overlap. Overlap test is not limited to the specific resource for
+ * which the CBM is intended though - when dealing with CDP resources that
+ * share the underlying hardware the overlap check should be performed on
+ * the CDP resource sharing the hardware also.
+ *
+ * Refer to description of __rdtgroup_cbm_overlaps() for the details of the
+ * overlap test.
+ *
+ * Return: true if CBM overlap detected, false if there is no overlap
+ */
+bool rdtgroup_cbm_overlaps(struct resctrl_schema *s, struct rdt_domain *d,
+			   unsigned long cbm, int closid, bool exclusive)
+{
+	enum resctrl_conf_type peer_type = resctrl_peer_type(s->conf_type);
+	struct rdt_resource *r = s->res;
+
+	if (__rdtgroup_cbm_overlaps(r, d, cbm, closid, s->conf_type,
+				    exclusive))
+		return true;
+
+	if (!resctrl_arch_get_cdp_enabled(r->rid))
+		return false;
+	return  __rdtgroup_cbm_overlaps(r, d, cbm, closid, peer_type, exclusive);
+}
+
+/**
+ * rdtgroup_mode_test_exclusive - Test if this resource group can be exclusive
+ *
+ * An exclusive resource group implies that there should be no sharing of
+ * its allocated resources. At the time this group is considered to be
+ * exclusive this test can determine if its current schemata supports this
+ * setting by testing for overlap with all other resource groups.
+ *
+ * Return: true if resource group can be exclusive, false if there is overlap
+ * with allocations of other resource groups and thus this resource group
+ * cannot be exclusive.
+ */
+static bool rdtgroup_mode_test_exclusive(struct rdtgroup *rdtgrp)
+{
+	int closid = rdtgrp->closid;
+	struct resctrl_schema *s;
+	struct rdt_resource *r;
+	bool has_cache = false;
+	struct rdt_domain *d;
+	u32 ctrl;
+
+	list_for_each_entry(s, &resctrl_schema_all, list) {
+		r = s->res;
+		if (r->rid == RDT_RESOURCE_MBA || r->rid == RDT_RESOURCE_SMBA)
+			continue;
+		has_cache = true;
+		list_for_each_entry(d, &r->domains, list) {
+			ctrl = resctrl_arch_get_config(r, d, closid,
+						       s->conf_type);
+			if (rdtgroup_cbm_overlaps(s, d, ctrl, closid, false)) {
+				rdt_last_cmd_puts("Schemata overlaps\n");
+				return false;
+			}
+		}
+	}
+
+	if (!has_cache) {
+		rdt_last_cmd_puts("Cannot be exclusive without CAT/CDP\n");
+		return false;
+	}
+
+	return true;
+}
+
+/**
+ * rdtgroup_mode_write - Modify the resource group's mode
+ *
+ */
+static ssize_t rdtgroup_mode_write(struct kernfs_open_file *of,
+				   char *buf, size_t nbytes, loff_t off)
+{
+	struct rdtgroup *rdtgrp;
+	enum rdtgrp_mode mode;
+	int ret = 0;
+
+	/* Valid input requires a trailing newline */
+	if (nbytes == 0 || buf[nbytes - 1] != '\n')
+		return -EINVAL;
+	buf[nbytes - 1] = '\0';
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (!rdtgrp) {
+		rdtgroup_kn_unlock(of->kn);
+		return -ENOENT;
+	}
+
+	rdt_last_cmd_clear();
+
+	mode = rdtgrp->mode;
+
+	if ((!strcmp(buf, "shareable") && mode == RDT_MODE_SHAREABLE) ||
+	    (!strcmp(buf, "exclusive") && mode == RDT_MODE_EXCLUSIVE) ||
+	    (!strcmp(buf, "pseudo-locksetup") &&
+	     mode == RDT_MODE_PSEUDO_LOCKSETUP) ||
+	    (!strcmp(buf, "pseudo-locked") && mode == RDT_MODE_PSEUDO_LOCKED))
+		goto out;
+
+	if (mode == RDT_MODE_PSEUDO_LOCKED) {
+		rdt_last_cmd_puts("Cannot change pseudo-locked group\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (!strcmp(buf, "shareable")) {
+		if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
+			ret = rdtgroup_locksetup_exit(rdtgrp);
+			if (ret)
+				goto out;
+		}
+		rdtgrp->mode = RDT_MODE_SHAREABLE;
+	} else if (!strcmp(buf, "exclusive")) {
+		if (!rdtgroup_mode_test_exclusive(rdtgrp)) {
+			ret = -EINVAL;
+			goto out;
+		}
+		if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
+			ret = rdtgroup_locksetup_exit(rdtgrp);
+			if (ret)
+				goto out;
+		}
+		rdtgrp->mode = RDT_MODE_EXCLUSIVE;
+	} else if (!strcmp(buf, "pseudo-locksetup")) {
+		ret = rdtgroup_locksetup_enter(rdtgrp);
+		if (ret)
+			goto out;
+		rdtgrp->mode = RDT_MODE_PSEUDO_LOCKSETUP;
+	} else {
+		rdt_last_cmd_puts("Unknown or unsupported mode\n");
+		ret = -EINVAL;
+	}
+
+out:
+	rdtgroup_kn_unlock(of->kn);
+	return ret ?: nbytes;
+}
+
+/**
+ * rdtgroup_cbm_to_size - Translate CBM to size in bytes
+ * @r: RDT resource to which @d belongs.
+ * @d: RDT domain instance.
+ * @cbm: bitmask for which the size should be computed.
+ *
+ * The bitmask provided associated with the RDT domain instance @d will be
+ * translated into how many bytes it represents. The size in bytes is
+ * computed by first dividing the total cache size by the CBM length to
+ * determine how many bytes each bit in the bitmask represents. The result
+ * is multiplied with the number of bits set in the bitmask.
+ *
+ * @cbm is unsigned long, even if only 32 bits are used to make the
+ * bitmap functions work correctly.
+ */
+unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r,
+				  struct rdt_domain *d, unsigned long cbm)
+{
+	struct cpu_cacheinfo *ci;
+	unsigned int size = 0;
+	int num_b, i;
+
+	num_b = bitmap_weight(&cbm, r->cache.cbm_len);
+	ci = get_cpu_cacheinfo(cpumask_any(&d->cpu_mask));
+	for (i = 0; i < ci->num_leaves; i++) {
+		if (ci->info_list[i].level == r->cache_level) {
+			size = ci->info_list[i].size / r->cache.cbm_len * num_b;
+			break;
+		}
+	}
+
+	return size;
+}
+
+/**
+ * rdtgroup_size_show - Display size in bytes of allocated regions
+ *
+ * The "size" file mirrors the layout of the "schemata" file, printing the
+ * size in bytes of each region instead of the capacity bitmask.
+ *
+ */
+static int rdtgroup_size_show(struct kernfs_open_file *of,
+			      struct seq_file *s, void *v)
+{
+	struct resctrl_schema *schema;
+	enum resctrl_conf_type type;
+	struct rdtgroup *rdtgrp;
+	struct rdt_resource *r;
+	struct rdt_domain *d;
+	unsigned int size;
+	int ret = 0;
+	u32 closid;
+	bool sep;
+	u32 ctrl;
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (!rdtgrp) {
+		rdtgroup_kn_unlock(of->kn);
+		return -ENOENT;
+	}
+
+	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) {
+		if (!rdtgrp->plr->d) {
+			rdt_last_cmd_clear();
+			rdt_last_cmd_puts("Cache domain offline\n");
+			ret = -ENODEV;
+		} else {
+			seq_printf(s, "%*s:", max_name_width,
+				   rdtgrp->plr->s->name);
+			size = rdtgroup_cbm_to_size(rdtgrp->plr->s->res,
+						    rdtgrp->plr->d,
+						    rdtgrp->plr->cbm);
+			seq_printf(s, "%d=%u\n", rdtgrp->plr->d->id, size);
+		}
+		goto out;
+	}
+
+	closid = rdtgrp->closid;
+
+	list_for_each_entry(schema, &resctrl_schema_all, list) {
+		r = schema->res;
+		type = schema->conf_type;
+		sep = false;
+		seq_printf(s, "%*s:", max_name_width, schema->name);
+		list_for_each_entry(d, &r->domains, list) {
+			if (sep)
+				seq_putc(s, ';');
+			if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
+				size = 0;
+			} else {
+				if (is_mba_sc(r))
+					ctrl = d->mbps_val[closid];
+				else
+					ctrl = resctrl_arch_get_config(r, d,
+								       closid,
+								       type);
+				if (r->rid == RDT_RESOURCE_MBA ||
+				    r->rid == RDT_RESOURCE_SMBA)
+					size = ctrl;
+				else
+					size = rdtgroup_cbm_to_size(r, d, ctrl);
+			}
+			seq_printf(s, "%d=%u", d->id, size);
+			sep = true;
+		}
+		seq_putc(s, '\n');
+	}
+
+out:
+	rdtgroup_kn_unlock(of->kn);
+
+	return ret;
+}
+
+struct mon_config_info {
+	u32 evtid;
+	u32 mon_config;
+};
+
+#define INVALID_CONFIG_INDEX   UINT_MAX
+
+/**
+ * mon_event_config_index_get - get the hardware index for the
+ *                              configurable event
+ * @evtid: event id.
+ *
+ * Return: 0 for evtid == QOS_L3_MBM_TOTAL_EVENT_ID
+ *         1 for evtid == QOS_L3_MBM_LOCAL_EVENT_ID
+ *         INVALID_CONFIG_INDEX for invalid evtid
+ */
+static inline unsigned int mon_event_config_index_get(u32 evtid)
+{
+	switch (evtid) {
+	case QOS_L3_MBM_TOTAL_EVENT_ID:
+		return 0;
+	case QOS_L3_MBM_LOCAL_EVENT_ID:
+		return 1;
+	default:
+		/* Should never reach here */
+		return INVALID_CONFIG_INDEX;
+	}
+}
+
+static void mon_event_config_read(void *info)
+{
+	struct mon_config_info *mon_info = info;
+	unsigned int index;
+	u64 msrval;
+
+	index = mon_event_config_index_get(mon_info->evtid);
+	if (index == INVALID_CONFIG_INDEX) {
+		pr_warn_once("Invalid event id %d\n", mon_info->evtid);
+		return;
+	}
+	rdmsrl(MSR_IA32_EVT_CFG_BASE + index, msrval);
+
+	/* Report only the valid event configuration bits */
+	mon_info->mon_config = msrval & MAX_EVT_CONFIG_BITS;
+}
+
+static void mondata_config_read(struct rdt_domain *d, struct mon_config_info *mon_info)
+{
+	smp_call_function_any(&d->cpu_mask, mon_event_config_read, mon_info, 1);
+}
+
+static int mbm_config_show(struct seq_file *s, struct rdt_resource *r, u32 evtid)
+{
+	struct mon_config_info mon_info = {0};
+	struct rdt_domain *dom;
+	bool sep = false;
+
+	mutex_lock(&rdtgroup_mutex);
+
+	list_for_each_entry(dom, &r->domains, list) {
+		if (sep)
+			seq_puts(s, ";");
+
+		memset(&mon_info, 0, sizeof(struct mon_config_info));
+		mon_info.evtid = evtid;
+		mondata_config_read(dom, &mon_info);
+
+		seq_printf(s, "%d=0x%02x", dom->id, mon_info.mon_config);
+		sep = true;
+	}
+	seq_puts(s, "\n");
+
+	mutex_unlock(&rdtgroup_mutex);
+
+	return 0;
+}
+
+static int mbm_total_bytes_config_show(struct kernfs_open_file *of,
+				       struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	mbm_config_show(seq, r, QOS_L3_MBM_TOTAL_EVENT_ID);
+
+	return 0;
+}
+
+static int mbm_local_bytes_config_show(struct kernfs_open_file *of,
+				       struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	mbm_config_show(seq, r, QOS_L3_MBM_LOCAL_EVENT_ID);
+
+	return 0;
+}
+
+static void mon_event_config_write(void *info)
+{
+	struct mon_config_info *mon_info = info;
+	unsigned int index;
+
+	index = mon_event_config_index_get(mon_info->evtid);
+	if (index == INVALID_CONFIG_INDEX) {
+		pr_warn_once("Invalid event id %d\n", mon_info->evtid);
+		return;
+	}
+	wrmsr(MSR_IA32_EVT_CFG_BASE + index, mon_info->mon_config, 0);
+}
+
+static int mbm_config_write_domain(struct rdt_resource *r,
+				   struct rdt_domain *d, u32 evtid, u32 val)
+{
+	struct mon_config_info mon_info = {0};
+	int ret = 0;
+
+	/* mon_config cannot be more than the supported set of events */
+	if (val > MAX_EVT_CONFIG_BITS) {
+		rdt_last_cmd_puts("Invalid event configuration\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Read the current config value first. If both are the same then
+	 * no need to write it again.
+	 */
+	mon_info.evtid = evtid;
+	mondata_config_read(d, &mon_info);
+	if (mon_info.mon_config == val)
+		goto out;
+
+	mon_info.mon_config = val;
+
+	/*
+	 * Update MSR_IA32_EVT_CFG_BASE MSR on one of the CPUs in the
+	 * domain. The MSRs offset from MSR MSR_IA32_EVT_CFG_BASE
+	 * are scoped at the domain level. Writing any of these MSRs
+	 * on one CPU is observed by all the CPUs in the domain.
+	 */
+	smp_call_function_any(&d->cpu_mask, mon_event_config_write,
+			      &mon_info, 1);
+
+	/*
+	 * When an Event Configuration is changed, the bandwidth counters
+	 * for all RMIDs and Events will be cleared by the hardware. The
+	 * hardware also sets MSR_IA32_QM_CTR.Unavailable (bit 62) for
+	 * every RMID on the next read to any event for every RMID.
+	 * Subsequent reads will have MSR_IA32_QM_CTR.Unavailable (bit 62)
+	 * cleared while it is tracked by the hardware. Clear the
+	 * mbm_local and mbm_total counts for all the RMIDs.
+	 */
+	resctrl_arch_reset_rmid_all(r, d);
+
+out:
+	return ret;
+}
+
+static int mon_config_write(struct rdt_resource *r, char *tok, u32 evtid)
+{
+	char *dom_str = NULL, *id_str;
+	unsigned long dom_id, val;
+	struct rdt_domain *d;
+	int ret = 0;
+
+next:
+	if (!tok || tok[0] == '\0')
+		return 0;
+
+	/* Start processing the strings for each domain */
+	dom_str = strim(strsep(&tok, ";"));
+	id_str = strsep(&dom_str, "=");
+
+	if (!id_str || kstrtoul(id_str, 10, &dom_id)) {
+		rdt_last_cmd_puts("Missing '=' or non-numeric domain id\n");
+		return -EINVAL;
+	}
+
+	if (!dom_str || kstrtoul(dom_str, 16, &val)) {
+		rdt_last_cmd_puts("Non-numeric event configuration value\n");
+		return -EINVAL;
+	}
+
+	list_for_each_entry(d, &r->domains, list) {
+		if (d->id == dom_id) {
+			ret = mbm_config_write_domain(r, d, evtid, val);
+			if (ret)
+				return -EINVAL;
+			goto next;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static ssize_t mbm_total_bytes_config_write(struct kernfs_open_file *of,
+					    char *buf, size_t nbytes,
+					    loff_t off)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+	int ret;
+
+	/* Valid input requires a trailing newline */
+	if (nbytes == 0 || buf[nbytes - 1] != '\n')
+		return -EINVAL;
+
+	mutex_lock(&rdtgroup_mutex);
+
+	rdt_last_cmd_clear();
+
+	buf[nbytes - 1] = '\0';
+
+	ret = mon_config_write(r, buf, QOS_L3_MBM_TOTAL_EVENT_ID);
+
+	mutex_unlock(&rdtgroup_mutex);
+
+	return ret ?: nbytes;
+}
+
+static ssize_t mbm_local_bytes_config_write(struct kernfs_open_file *of,
+					    char *buf, size_t nbytes,
+					    loff_t off)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+	int ret;
+
+	/* Valid input requires a trailing newline */
+	if (nbytes == 0 || buf[nbytes - 1] != '\n')
+		return -EINVAL;
+
+	mutex_lock(&rdtgroup_mutex);
+
+	rdt_last_cmd_clear();
+
+	buf[nbytes - 1] = '\0';
+
+	ret = mon_config_write(r, buf, QOS_L3_MBM_LOCAL_EVENT_ID);
+
+	mutex_unlock(&rdtgroup_mutex);
+
+	return ret ?: nbytes;
+}
+
+/* rdtgroup information files for one cache resource. */
+static struct rftype res_common_files[] = {
+	{
+		.name		= "last_cmd_status",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_last_cmd_status_show,
+		.fflags		= RF_TOP_INFO,
+	},
+	{
+		.name		= "num_closids",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_num_closids_show,
+		.fflags		= RF_CTRL_INFO,
+	},
+	{
+		.name		= "mon_features",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_mon_features_show,
+		.fflags		= RF_MON_INFO,
+	},
+	{
+		.name		= "num_rmids",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_num_rmids_show,
+		.fflags		= RF_MON_INFO,
+	},
+	{
+		.name		= "cbm_mask",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_default_ctrl_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_CACHE,
+	},
+	{
+		.name		= "min_cbm_bits",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_min_cbm_bits_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_CACHE,
+	},
+	{
+		.name		= "shareable_bits",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_shareable_bits_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_CACHE,
+	},
+	{
+		.name		= "bit_usage",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_bit_usage_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_CACHE,
+	},
+	{
+		.name		= "min_bandwidth",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_min_bw_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_MB,
+	},
+	{
+		.name		= "bandwidth_gran",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_bw_gran_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_MB,
+	},
+	{
+		.name		= "delay_linear",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_delay_linear_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_MB,
+	},
+	/*
+	 * Platform specific which (if any) capabilities are provided by
+	 * thread_throttle_mode. Defer "fflags" initialization to platform
+	 * discovery.
+	 */
+	{
+		.name		= "thread_throttle_mode",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_thread_throttle_mode_show,
+	},
+	{
+		.name		= "max_threshold_occupancy",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= max_threshold_occ_write,
+		.seq_show	= max_threshold_occ_show,
+		.fflags		= RF_MON_INFO | RFTYPE_RES_CACHE,
+	},
+	{
+		.name		= "mbm_total_bytes_config",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= mbm_total_bytes_config_show,
+		.write		= mbm_total_bytes_config_write,
+	},
+	{
+		.name		= "mbm_local_bytes_config",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= mbm_local_bytes_config_show,
+		.write		= mbm_local_bytes_config_write,
+	},
+	{
+		.name		= "cpus",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= rdtgroup_cpus_write,
+		.seq_show	= rdtgroup_cpus_show,
+		.fflags		= RFTYPE_BASE,
+	},
+	{
+		.name		= "cpus_list",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= rdtgroup_cpus_write,
+		.seq_show	= rdtgroup_cpus_show,
+		.flags		= RFTYPE_FLAGS_CPUS_LIST,
+		.fflags		= RFTYPE_BASE,
+	},
+	{
+		.name		= "tasks",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= rdtgroup_tasks_write,
+		.seq_show	= rdtgroup_tasks_show,
+		.fflags		= RFTYPE_BASE,
+	},
+	{
+		.name		= "schemata",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= rdtgroup_schemata_write,
+		.seq_show	= rdtgroup_schemata_show,
+		.fflags		= RF_CTRL_BASE,
+	},
+	{
+		.name		= "mode",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.write		= rdtgroup_mode_write,
+		.seq_show	= rdtgroup_mode_show,
+		.fflags		= RF_CTRL_BASE,
+	},
+	{
+		.name		= "size",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdtgroup_size_show,
+		.fflags		= RF_CTRL_BASE,
+	},
+
+};
+
+static int rdtgroup_add_files(struct kernfs_node *kn, unsigned long fflags)
+{
+	struct rftype *rfts, *rft;
+	int ret, len;
+
+	rfts = res_common_files;
+	len = ARRAY_SIZE(res_common_files);
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	for (rft = rfts; rft < rfts + len; rft++) {
+		if (rft->fflags && ((fflags & rft->fflags) == rft->fflags)) {
+			ret = rdtgroup_add_file(kn, rft);
+			if (ret)
+				goto error;
+		}
+	}
+
+	return 0;
+error:
+	pr_warn("Failed to add %s, err=%d\n", rft->name, ret);
+	while (--rft >= rfts) {
+		if ((fflags & rft->fflags) == rft->fflags)
+			kernfs_remove_by_name(kn, rft->name);
+	}
+	return ret;
+}
+
+static struct rftype *rdtgroup_get_rftype_by_name(const char *name)
+{
+	struct rftype *rfts, *rft;
+	int len;
+
+	rfts = res_common_files;
+	len = ARRAY_SIZE(res_common_files);
+
+	for (rft = rfts; rft < rfts + len; rft++) {
+		if (!strcmp(rft->name, name))
+			return rft;
+	}
+
+	return NULL;
+}
+
+void __init thread_throttle_mode_init(void)
+{
+	struct rftype *rft;
+
+	rft = rdtgroup_get_rftype_by_name("thread_throttle_mode");
+	if (!rft)
+		return;
+
+	rft->fflags = RF_CTRL_INFO | RFTYPE_RES_MB;
+}
+
+void __init mbm_config_rftype_init(const char *config)
+{
+	struct rftype *rft;
+
+	rft = rdtgroup_get_rftype_by_name(config);
+	if (rft)
+		rft->fflags = RF_MON_INFO | RFTYPE_RES_CACHE;
+}
+
+/**
+ * rdtgroup_kn_mode_restrict - Restrict user access to named resctrl file
+ * @r: The resource group with which the file is associated.
+ * @name: Name of the file
+ *
+ * The permissions of named resctrl file, directory, or link are modified
+ * to not allow read, write, or execute by any user.
+ *
+ * WARNING: This function is intended to communicate to the user that the
+ * resctrl file has been locked down - that it is not relevant to the
+ * particular state the system finds itself in. It should not be relied
+ * on to protect from user access because after the file's permissions
+ * are restricted the user can still change the permissions using chmod
+ * from the command line.
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int rdtgroup_kn_mode_restrict(struct rdtgroup *r, const char *name)
+{
+	struct iattr iattr = {.ia_valid = ATTR_MODE,};
+	struct kernfs_node *kn;
+	int ret = 0;
+
+	kn = kernfs_find_and_get_ns(r->kn, name, NULL);
+	if (!kn)
+		return -ENOENT;
+
+	switch (kernfs_type(kn)) {
+	case KERNFS_DIR:
+		iattr.ia_mode = S_IFDIR;
+		break;
+	case KERNFS_FILE:
+		iattr.ia_mode = S_IFREG;
+		break;
+	case KERNFS_LINK:
+		iattr.ia_mode = S_IFLNK;
+		break;
+	}
+
+	ret = kernfs_setattr(kn, &iattr);
+	kernfs_put(kn);
+	return ret;
+}
+
+/**
+ * rdtgroup_kn_mode_restore - Restore user access to named resctrl file
+ * @r: The resource group with which the file is associated.
+ * @name: Name of the file
+ * @mask: Mask of permissions that should be restored
+ *
+ * Restore the permissions of the named file. If @name is a directory the
+ * permissions of its parent will be used.
+ *
+ * Return: 0 on success, <0 on failure.
+ */
+int rdtgroup_kn_mode_restore(struct rdtgroup *r, const char *name,
+			     umode_t mask)
+{
+	struct iattr iattr = {.ia_valid = ATTR_MODE,};
+	struct kernfs_node *kn, *parent;
+	struct rftype *rfts, *rft;
+	int ret, len;
+
+	rfts = res_common_files;
+	len = ARRAY_SIZE(res_common_files);
+
+	for (rft = rfts; rft < rfts + len; rft++) {
+		if (!strcmp(rft->name, name))
+			iattr.ia_mode = rft->mode & mask;
+	}
+
+	kn = kernfs_find_and_get_ns(r->kn, name, NULL);
+	if (!kn)
+		return -ENOENT;
+
+	switch (kernfs_type(kn)) {
+	case KERNFS_DIR:
+		parent = kernfs_get_parent(kn);
+		if (parent) {
+			iattr.ia_mode |= parent->mode;
+			kernfs_put(parent);
+		}
+		iattr.ia_mode |= S_IFDIR;
+		break;
+	case KERNFS_FILE:
+		iattr.ia_mode |= S_IFREG;
+		break;
+	case KERNFS_LINK:
+		iattr.ia_mode |= S_IFLNK;
+		break;
+	}
+
+	ret = kernfs_setattr(kn, &iattr);
+	kernfs_put(kn);
+	return ret;
+}
+
+static int rdtgroup_mkdir_info_resdir(void *priv, char *name,
+				      unsigned long fflags)
+{
+	struct kernfs_node *kn_subdir;
+	int ret;
+
+	kn_subdir = kernfs_create_dir(kn_info, name,
+				      kn_info->mode, priv);
+	if (IS_ERR(kn_subdir))
+		return PTR_ERR(kn_subdir);
+
+	ret = rdtgroup_kn_set_ugid(kn_subdir);
+	if (ret)
+		return ret;
+
+	ret = rdtgroup_add_files(kn_subdir, fflags);
+	if (!ret)
+		kernfs_activate(kn_subdir);
+
+	return ret;
+}
+
+static int rdtgroup_create_info_dir(struct kernfs_node *parent_kn)
+{
+	struct resctrl_schema *s;
+	struct rdt_resource *r;
+	unsigned long fflags;
+	char name[32];
+	int ret;
+
+	/* create the directory */
+	kn_info = kernfs_create_dir(parent_kn, "info", parent_kn->mode, NULL);
+	if (IS_ERR(kn_info))
+		return PTR_ERR(kn_info);
+
+	ret = rdtgroup_add_files(kn_info, RF_TOP_INFO);
+	if (ret)
+		goto out_destroy;
+
+	/* loop over enabled controls, these are all alloc_capable */
+	list_for_each_entry(s, &resctrl_schema_all, list) {
+		r = s->res;
+		fflags =  r->fflags | RF_CTRL_INFO;
+		ret = rdtgroup_mkdir_info_resdir(s, s->name, fflags);
+		if (ret)
+			goto out_destroy;
+	}
+
+	for_each_mon_capable_rdt_resource(r) {
+		fflags =  r->fflags | RF_MON_INFO;
+		sprintf(name, "%s_MON", r->name);
+		ret = rdtgroup_mkdir_info_resdir(r, name, fflags);
+		if (ret)
+			goto out_destroy;
+	}
+
+	ret = rdtgroup_kn_set_ugid(kn_info);
+	if (ret)
+		goto out_destroy;
+
+	kernfs_activate(kn_info);
+
+	return 0;
+
+out_destroy:
+	kernfs_remove(kn_info);
+	return ret;
+}
+
+static int
+mongroup_create_dir(struct kernfs_node *parent_kn, struct rdtgroup *prgrp,
+		    char *name, struct kernfs_node **dest_kn)
+{
+	struct kernfs_node *kn;
+	int ret;
+
+	/* create the directory */
+	kn = kernfs_create_dir(parent_kn, name, parent_kn->mode, prgrp);
+	if (IS_ERR(kn))
+		return PTR_ERR(kn);
+
+	if (dest_kn)
+		*dest_kn = kn;
+
+	ret = rdtgroup_kn_set_ugid(kn);
+	if (ret)
+		goto out_destroy;
+
+	kernfs_activate(kn);
+
+	return 0;
+
+out_destroy:
+	kernfs_remove(kn);
+	return ret;
+}
+
+static void l3_qos_cfg_update(void *arg)
+{
+	bool *enable = arg;
+
+	wrmsrl(MSR_IA32_L3_QOS_CFG, *enable ? L3_QOS_CDP_ENABLE : 0ULL);
+}
+
+static void l2_qos_cfg_update(void *arg)
+{
+	bool *enable = arg;
+
+	wrmsrl(MSR_IA32_L2_QOS_CFG, *enable ? L2_QOS_CDP_ENABLE : 0ULL);
+}
+
+static inline bool is_mba_linear(void)
+{
+	return rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl.membw.delay_linear;
+}
+
+static int set_cache_qos_cfg(int level, bool enable)
+{
+	void (*update)(void *arg);
+	struct rdt_resource *r_l;
+	cpumask_var_t cpu_mask;
+	struct rdt_domain *d;
+	int cpu;
+
+	if (level == RDT_RESOURCE_L3)
+		update = l3_qos_cfg_update;
+	else if (level == RDT_RESOURCE_L2)
+		update = l2_qos_cfg_update;
+	else
+		return -EINVAL;
+
+	if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))
+		return -ENOMEM;
+
+	r_l = &rdt_resources_all[level].r_resctrl;
+	list_for_each_entry(d, &r_l->domains, list) {
+		if (r_l->cache.arch_has_per_cpu_cfg)
+			/* Pick all the CPUs in the domain instance */
+			for_each_cpu(cpu, &d->cpu_mask)
+				cpumask_set_cpu(cpu, cpu_mask);
+		else
+			/* Pick one CPU from each domain instance to update MSR */
+			cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask);
+	}
+
+	/* Update QOS_CFG MSR on all the CPUs in cpu_mask */
+	on_each_cpu_mask(cpu_mask, update, &enable, 1);
+
+	free_cpumask_var(cpu_mask);
+
+	return 0;
+}
+
+/* Restore the qos cfg state when a domain comes online */
+void rdt_domain_reconfigure_cdp(struct rdt_resource *r)
+{
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+
+	if (!r->cdp_capable)
+		return;
+
+	if (r->rid == RDT_RESOURCE_L2)
+		l2_qos_cfg_update(&hw_res->cdp_enabled);
+
+	if (r->rid == RDT_RESOURCE_L3)
+		l3_qos_cfg_update(&hw_res->cdp_enabled);
+}
+
+static int mba_sc_domain_allocate(struct rdt_resource *r, struct rdt_domain *d)
+{
+	u32 num_closid = resctrl_arch_get_num_closid(r);
+	int cpu = cpumask_any(&d->cpu_mask);
+	int i;
+
+	d->mbps_val = kcalloc_node(num_closid, sizeof(*d->mbps_val),
+				   GFP_KERNEL, cpu_to_node(cpu));
+	if (!d->mbps_val)
+		return -ENOMEM;
+
+	for (i = 0; i < num_closid; i++)
+		d->mbps_val[i] = MBA_MAX_MBPS;
+
+	return 0;
+}
+
+static void mba_sc_domain_destroy(struct rdt_resource *r,
+				  struct rdt_domain *d)
+{
+	kfree(d->mbps_val);
+	d->mbps_val = NULL;
+}
+
+/*
+ * MBA software controller is supported only if
+ * MBM is supported and MBA is in linear scale.
+ */
+static bool supports_mba_mbps(void)
+{
+	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl;
+
+	return (is_mbm_local_enabled() &&
+		r->alloc_capable && is_mba_linear());
+}
+
+/*
+ * Enable or disable the MBA software controller
+ * which helps user specify bandwidth in MBps.
+ */
+static int set_mba_sc(bool mba_sc)
+{
+	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl;
+	u32 num_closid = resctrl_arch_get_num_closid(r);
+	struct rdt_domain *d;
+	int i;
+
+	if (!supports_mba_mbps() || mba_sc == is_mba_sc(r))
+		return -EINVAL;
+
+	r->membw.mba_sc = mba_sc;
+
+	list_for_each_entry(d, &r->domains, list) {
+		for (i = 0; i < num_closid; i++)
+			d->mbps_val[i] = MBA_MAX_MBPS;
+	}
+
+	return 0;
+}
+
+static int cdp_enable(int level)
+{
+	struct rdt_resource *r_l = &rdt_resources_all[level].r_resctrl;
+	int ret;
+
+	if (!r_l->alloc_capable)
+		return -EINVAL;
+
+	ret = set_cache_qos_cfg(level, true);
+	if (!ret)
+		rdt_resources_all[level].cdp_enabled = true;
+
+	return ret;
+}
+
+static void cdp_disable(int level)
+{
+	struct rdt_hw_resource *r_hw = &rdt_resources_all[level];
+
+	if (r_hw->cdp_enabled) {
+		set_cache_qos_cfg(level, false);
+		r_hw->cdp_enabled = false;
+	}
+}
+
+int resctrl_arch_set_cdp_enabled(enum resctrl_res_level l, bool enable)
+{
+	struct rdt_hw_resource *hw_res = &rdt_resources_all[l];
+
+	if (!hw_res->r_resctrl.cdp_capable)
+		return -EINVAL;
+
+	if (enable)
+		return cdp_enable(l);
+
+	cdp_disable(l);
+
+	return 0;
+}
+
+static void cdp_disable_all(void)
+{
+	if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L3))
+		resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, false);
+	if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L2))
+		resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, false);
+}
+
+/*
+ * We don't allow rdtgroup directories to be created anywhere
+ * except the root directory. Thus when looking for the rdtgroup
+ * structure for a kernfs node we are either looking at a directory,
+ * in which case the rdtgroup structure is pointed at by the "priv"
+ * field, otherwise we have a file, and need only look to the parent
+ * to find the rdtgroup.
+ */
+static struct rdtgroup *kernfs_to_rdtgroup(struct kernfs_node *kn)
+{
+	if (kernfs_type(kn) == KERNFS_DIR) {
+		/*
+		 * All the resource directories use "kn->priv"
+		 * to point to the "struct rdtgroup" for the
+		 * resource. "info" and its subdirectories don't
+		 * have rdtgroup structures, so return NULL here.
+		 */
+		if (kn == kn_info || kn->parent == kn_info)
+			return NULL;
+		else
+			return kn->priv;
+	} else {
+		return kn->parent->priv;
+	}
+}
+
+static void rdtgroup_kn_get(struct rdtgroup *rdtgrp, struct kernfs_node *kn)
+{
+	atomic_inc(&rdtgrp->waitcount);
+	kernfs_break_active_protection(kn);
+}
+
+static void rdtgroup_kn_put(struct rdtgroup *rdtgrp, struct kernfs_node *kn)
+{
+	if (atomic_dec_and_test(&rdtgrp->waitcount) &&
+	    (rdtgrp->flags & RDT_DELETED)) {
+		if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP ||
+		    rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED)
+			rdtgroup_pseudo_lock_remove(rdtgrp);
+		kernfs_unbreak_active_protection(kn);
+		rdtgroup_remove(rdtgrp);
+	} else {
+		kernfs_unbreak_active_protection(kn);
+	}
+}
+
+struct rdtgroup *rdtgroup_kn_lock_live(struct kernfs_node *kn)
+{
+	struct rdtgroup *rdtgrp = kernfs_to_rdtgroup(kn);
+
+	if (!rdtgrp)
+		return NULL;
+
+	rdtgroup_kn_get(rdtgrp, kn);
+
+	mutex_lock(&rdtgroup_mutex);
+
+	/* Was this group deleted while we waited? */
+	if (rdtgrp->flags & RDT_DELETED)
+		return NULL;
+
+	return rdtgrp;
+}
+
+void rdtgroup_kn_unlock(struct kernfs_node *kn)
+{
+	struct rdtgroup *rdtgrp = kernfs_to_rdtgroup(kn);
+
+	if (!rdtgrp)
+		return;
+
+	mutex_unlock(&rdtgroup_mutex);
+	rdtgroup_kn_put(rdtgrp, kn);
+}
+
+static int mkdir_mondata_all(struct kernfs_node *parent_kn,
+			     struct rdtgroup *prgrp,
+			     struct kernfs_node **mon_data_kn);
+
+static int rdt_enable_ctx(struct rdt_fs_context *ctx)
+{
+	int ret = 0;
+
+	if (ctx->enable_cdpl2)
+		ret = resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, true);
+
+	if (!ret && ctx->enable_cdpl3)
+		ret = resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, true);
+
+	if (!ret && ctx->enable_mba_mbps)
+		ret = set_mba_sc(true);
+
+	return ret;
+}
+
+static int schemata_list_add(struct rdt_resource *r, enum resctrl_conf_type type)
+{
+	struct resctrl_schema *s;
+	const char *suffix = "";
+	int ret, cl;
+
+	s = kzalloc(sizeof(*s), GFP_KERNEL);
+	if (!s)
+		return -ENOMEM;
+
+	s->res = r;
+	s->num_closid = resctrl_arch_get_num_closid(r);
+	if (resctrl_arch_get_cdp_enabled(r->rid))
+		s->num_closid /= 2;
+
+	s->conf_type = type;
+	switch (type) {
+	case CDP_CODE:
+		suffix = "CODE";
+		break;
+	case CDP_DATA:
+		suffix = "DATA";
+		break;
+	case CDP_NONE:
+		suffix = "";
+		break;
+	}
+
+	ret = snprintf(s->name, sizeof(s->name), "%s%s", r->name, suffix);
+	if (ret >= sizeof(s->name)) {
+		kfree(s);
+		return -EINVAL;
+	}
+
+	cl = strlen(s->name);
+
+	/*
+	 * If CDP is supported by this resource, but not enabled,
+	 * include the suffix. This ensures the tabular format of the
+	 * schemata file does not change between mounts of the filesystem.
+	 */
+	if (r->cdp_capable && !resctrl_arch_get_cdp_enabled(r->rid))
+		cl += 4;
+
+	if (cl > max_name_width)
+		max_name_width = cl;
+
+	INIT_LIST_HEAD(&s->list);
+	list_add(&s->list, &resctrl_schema_all);
+
+	return 0;
+}
+
+static int schemata_list_create(void)
+{
+	struct rdt_resource *r;
+	int ret = 0;
+
+	for_each_alloc_capable_rdt_resource(r) {
+		if (resctrl_arch_get_cdp_enabled(r->rid)) {
+			ret = schemata_list_add(r, CDP_CODE);
+			if (ret)
+				break;
+
+			ret = schemata_list_add(r, CDP_DATA);
+		} else {
+			ret = schemata_list_add(r, CDP_NONE);
+		}
+
+		if (ret)
+			break;
+	}
+
+	return ret;
+}
+
+static void schemata_list_destroy(void)
+{
+	struct resctrl_schema *s, *tmp;
+
+	list_for_each_entry_safe(s, tmp, &resctrl_schema_all, list) {
+		list_del(&s->list);
+		kfree(s);
+	}
+}
+
+static int rdt_get_tree(struct fs_context *fc)
+{
+	struct rdt_fs_context *ctx = rdt_fc2context(fc);
+	struct rdt_domain *dom;
+	struct rdt_resource *r;
+	int ret;
+
+	cpus_read_lock();
+	mutex_lock(&rdtgroup_mutex);
+	/*
+	 * resctrl file system can only be mounted once.
+	 */
+	if (static_branch_unlikely(&rdt_enable_key)) {
+		ret = -EBUSY;
+		goto out;
+	}
+
+	ret = rdt_enable_ctx(ctx);
+	if (ret < 0)
+		goto out_cdp;
+
+	ret = schemata_list_create();
+	if (ret) {
+		schemata_list_destroy();
+		goto out_mba;
+	}
+
+	closid_init();
+
+	ret = rdtgroup_create_info_dir(rdtgroup_default.kn);
+	if (ret < 0)
+		goto out_schemata_free;
+
+	if (rdt_mon_capable) {
+		ret = mongroup_create_dir(rdtgroup_default.kn,
+					  &rdtgroup_default, "mon_groups",
+					  &kn_mongrp);
+		if (ret < 0)
+			goto out_info;
+
+		ret = mkdir_mondata_all(rdtgroup_default.kn,
+					&rdtgroup_default, &kn_mondata);
+		if (ret < 0)
+			goto out_mongrp;
+		rdtgroup_default.mon.mon_data_kn = kn_mondata;
+	}
+
+	ret = rdt_pseudo_lock_init();
+	if (ret)
+		goto out_mondata;
+
+	ret = kernfs_get_tree(fc);
+	if (ret < 0)
+		goto out_psl;
+
+	if (rdt_alloc_capable)
+		static_branch_enable_cpuslocked(&rdt_alloc_enable_key);
+	if (rdt_mon_capable)
+		static_branch_enable_cpuslocked(&rdt_mon_enable_key);
+
+	if (rdt_alloc_capable || rdt_mon_capable)
+		static_branch_enable_cpuslocked(&rdt_enable_key);
+
+	if (is_mbm_enabled()) {
+		r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+		list_for_each_entry(dom, &r->domains, list)
+			mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL);
+	}
+
+	goto out;
+
+out_psl:
+	rdt_pseudo_lock_release();
+out_mondata:
+	if (rdt_mon_capable)
+		kernfs_remove(kn_mondata);
+out_mongrp:
+	if (rdt_mon_capable)
+		kernfs_remove(kn_mongrp);
+out_info:
+	kernfs_remove(kn_info);
+out_schemata_free:
+	schemata_list_destroy();
+out_mba:
+	if (ctx->enable_mba_mbps)
+		set_mba_sc(false);
+out_cdp:
+	cdp_disable_all();
+out:
+	rdt_last_cmd_clear();
+	mutex_unlock(&rdtgroup_mutex);
+	cpus_read_unlock();
+	return ret;
+}
+
+enum rdt_param {
+	Opt_cdp,
+	Opt_cdpl2,
+	Opt_mba_mbps,
+	nr__rdt_params
+};
+
+static const struct fs_parameter_spec rdt_fs_parameters[] = {
+	fsparam_flag("cdp",		Opt_cdp),
+	fsparam_flag("cdpl2",		Opt_cdpl2),
+	fsparam_flag("mba_MBps",	Opt_mba_mbps),
+	{}
+};
+
+static int rdt_parse_param(struct fs_context *fc, struct fs_parameter *param)
+{
+	struct rdt_fs_context *ctx = rdt_fc2context(fc);
+	struct fs_parse_result result;
+	int opt;
+
+	opt = fs_parse(fc, rdt_fs_parameters, param, &result);
+	if (opt < 0)
+		return opt;
+
+	switch (opt) {
+	case Opt_cdp:
+		ctx->enable_cdpl3 = true;
+		return 0;
+	case Opt_cdpl2:
+		ctx->enable_cdpl2 = true;
+		return 0;
+	case Opt_mba_mbps:
+		if (!supports_mba_mbps())
+			return -EINVAL;
+		ctx->enable_mba_mbps = true;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static void rdt_fs_context_free(struct fs_context *fc)
+{
+	struct rdt_fs_context *ctx = rdt_fc2context(fc);
+
+	kernfs_free_fs_context(fc);
+	kfree(ctx);
+}
+
+static const struct fs_context_operations rdt_fs_context_ops = {
+	.free		= rdt_fs_context_free,
+	.parse_param	= rdt_parse_param,
+	.get_tree	= rdt_get_tree,
+};
+
+static int rdt_init_fs_context(struct fs_context *fc)
+{
+	struct rdt_fs_context *ctx;
+
+	ctx = kzalloc(sizeof(struct rdt_fs_context), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->kfc.root = rdt_root;
+	ctx->kfc.magic = RDTGROUP_SUPER_MAGIC;
+	fc->fs_private = &ctx->kfc;
+	fc->ops = &rdt_fs_context_ops;
+	put_user_ns(fc->user_ns);
+	fc->user_ns = get_user_ns(&init_user_ns);
+	fc->global = true;
+	return 0;
+}
+
+static int reset_all_ctrls(struct rdt_resource *r)
+{
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+	struct rdt_hw_domain *hw_dom;
+	struct msr_param msr_param;
+	cpumask_var_t cpu_mask;
+	struct rdt_domain *d;
+	int i;
+
+	if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))
+		return -ENOMEM;
+
+	msr_param.res = r;
+	msr_param.low = 0;
+	msr_param.high = hw_res->num_closid;
+
+	/*
+	 * Disable resource control for this resource by setting all
+	 * CBMs in all domains to the maximum mask value. Pick one CPU
+	 * from each domain to update the MSRs below.
+	 */
+	list_for_each_entry(d, &r->domains, list) {
+		hw_dom = resctrl_to_arch_dom(d);
+		cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask);
+
+		for (i = 0; i < hw_res->num_closid; i++)
+			hw_dom->ctrl_val[i] = r->default_ctrl;
+	}
+
+	/* Update CBM on all the CPUs in cpu_mask */
+	on_each_cpu_mask(cpu_mask, rdt_ctrl_update, &msr_param, 1);
+
+	free_cpumask_var(cpu_mask);
+
+	return 0;
+}
+
+/*
+ * Move tasks from one to the other group. If @from is NULL, then all tasks
+ * in the systems are moved unconditionally (used for teardown).
+ *
+ * If @mask is not NULL the cpus on which moved tasks are running are set
+ * in that mask so the update smp function call is restricted to affected
+ * cpus.
+ */
+static void rdt_move_group_tasks(struct rdtgroup *from, struct rdtgroup *to,
+				 struct cpumask *mask)
+{
+	struct task_struct *p, *t;
+
+	read_lock(&tasklist_lock);
+	for_each_process_thread(p, t) {
+		if (!from || is_closid_match(t, from) ||
+		    is_rmid_match(t, from)) {
+			WRITE_ONCE(t->closid, to->closid);
+			WRITE_ONCE(t->rmid, to->mon.rmid);
+
+			/*
+			 * Order the closid/rmid stores above before the loads
+			 * in task_curr(). This pairs with the full barrier
+			 * between the rq->curr update and resctrl_sched_in()
+			 * during context switch.
+			 */
+			smp_mb();
+
+			/*
+			 * If the task is on a CPU, set the CPU in the mask.
+			 * The detection is inaccurate as tasks might move or
+			 * schedule before the smp function call takes place.
+			 * In such a case the function call is pointless, but
+			 * there is no other side effect.
+			 */
+			if (IS_ENABLED(CONFIG_SMP) && mask && task_curr(t))
+				cpumask_set_cpu(task_cpu(t), mask);
+		}
+	}
+	read_unlock(&tasklist_lock);
+}
+
+static void free_all_child_rdtgrp(struct rdtgroup *rdtgrp)
+{
+	struct rdtgroup *sentry, *stmp;
+	struct list_head *head;
+
+	head = &rdtgrp->mon.crdtgrp_list;
+	list_for_each_entry_safe(sentry, stmp, head, mon.crdtgrp_list) {
+		free_rmid(sentry->mon.rmid);
+		list_del(&sentry->mon.crdtgrp_list);
+
+		if (atomic_read(&sentry->waitcount) != 0)
+			sentry->flags = RDT_DELETED;
+		else
+			rdtgroup_remove(sentry);
+	}
+}
+
+/*
+ * Forcibly remove all of subdirectories under root.
+ */
+static void rmdir_all_sub(void)
+{
+	struct rdtgroup *rdtgrp, *tmp;
+
+	/* Move all tasks to the default resource group */
+	rdt_move_group_tasks(NULL, &rdtgroup_default, NULL);
+
+	list_for_each_entry_safe(rdtgrp, tmp, &rdt_all_groups, rdtgroup_list) {
+		/* Free any child rmids */
+		free_all_child_rdtgrp(rdtgrp);
+
+		/* Remove each rdtgroup other than root */
+		if (rdtgrp == &rdtgroup_default)
+			continue;
+
+		if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP ||
+		    rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED)
+			rdtgroup_pseudo_lock_remove(rdtgrp);
+
+		/*
+		 * Give any CPUs back to the default group. We cannot copy
+		 * cpu_online_mask because a CPU might have executed the
+		 * offline callback already, but is still marked online.
+		 */
+		cpumask_or(&rdtgroup_default.cpu_mask,
+			   &rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
+
+		free_rmid(rdtgrp->mon.rmid);
+
+		kernfs_remove(rdtgrp->kn);
+		list_del(&rdtgrp->rdtgroup_list);
+
+		if (atomic_read(&rdtgrp->waitcount) != 0)
+			rdtgrp->flags = RDT_DELETED;
+		else
+			rdtgroup_remove(rdtgrp);
+	}
+	/* Notify online CPUs to update per cpu storage and PQR_ASSOC MSR */
+	update_closid_rmid(cpu_online_mask, &rdtgroup_default);
+
+	kernfs_remove(kn_info);
+	kernfs_remove(kn_mongrp);
+	kernfs_remove(kn_mondata);
+}
+
+static void rdt_kill_sb(struct super_block *sb)
+{
+	struct rdt_resource *r;
+
+	cpus_read_lock();
+	mutex_lock(&rdtgroup_mutex);
+
+	set_mba_sc(false);
+
+	/*Put everything back to default values. */
+	for_each_alloc_capable_rdt_resource(r)
+		reset_all_ctrls(r);
+	cdp_disable_all();
+	rmdir_all_sub();
+	rdt_pseudo_lock_release();
+	rdtgroup_default.mode = RDT_MODE_SHAREABLE;
+	schemata_list_destroy();
+	static_branch_disable_cpuslocked(&rdt_alloc_enable_key);
+	static_branch_disable_cpuslocked(&rdt_mon_enable_key);
+	static_branch_disable_cpuslocked(&rdt_enable_key);
+	kernfs_kill_sb(sb);
+	mutex_unlock(&rdtgroup_mutex);
+	cpus_read_unlock();
+}
+
+static struct file_system_type rdt_fs_type = {
+	.name			= "resctrl",
+	.init_fs_context	= rdt_init_fs_context,
+	.parameters		= rdt_fs_parameters,
+	.kill_sb		= rdt_kill_sb,
+};
+
+static int mon_addfile(struct kernfs_node *parent_kn, const char *name,
+		       void *priv)
+{
+	struct kernfs_node *kn;
+	int ret = 0;
+
+	kn = __kernfs_create_file(parent_kn, name, 0444,
+				  GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, 0,
+				  &kf_mondata_ops, priv, NULL, NULL);
+	if (IS_ERR(kn))
+		return PTR_ERR(kn);
+
+	ret = rdtgroup_kn_set_ugid(kn);
+	if (ret) {
+		kernfs_remove(kn);
+		return ret;
+	}
+
+	return ret;
+}
+
+/*
+ * Remove all subdirectories of mon_data of ctrl_mon groups
+ * and monitor groups with given domain id.
+ */
+static void rmdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
+					   unsigned int dom_id)
+{
+	struct rdtgroup *prgrp, *crgrp;
+	char name[32];
+
+	list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
+		sprintf(name, "mon_%s_%02d", r->name, dom_id);
+		kernfs_remove_by_name(prgrp->mon.mon_data_kn, name);
+
+		list_for_each_entry(crgrp, &prgrp->mon.crdtgrp_list, mon.crdtgrp_list)
+			kernfs_remove_by_name(crgrp->mon.mon_data_kn, name);
+	}
+}
+
+static int mkdir_mondata_subdir(struct kernfs_node *parent_kn,
+				struct rdt_domain *d,
+				struct rdt_resource *r, struct rdtgroup *prgrp)
+{
+	union mon_data_bits priv;
+	struct kernfs_node *kn;
+	struct mon_evt *mevt;
+	struct rmid_read rr;
+	char name[32];
+	int ret;
+
+	sprintf(name, "mon_%s_%02d", r->name, d->id);
+	/* create the directory */
+	kn = kernfs_create_dir(parent_kn, name, parent_kn->mode, prgrp);
+	if (IS_ERR(kn))
+		return PTR_ERR(kn);
+
+	ret = rdtgroup_kn_set_ugid(kn);
+	if (ret)
+		goto out_destroy;
+
+	if (WARN_ON(list_empty(&r->evt_list))) {
+		ret = -EPERM;
+		goto out_destroy;
+	}
+
+	priv.u.rid = r->rid;
+	priv.u.domid = d->id;
+	list_for_each_entry(mevt, &r->evt_list, list) {
+		priv.u.evtid = mevt->evtid;
+		ret = mon_addfile(kn, mevt->name, priv.priv);
+		if (ret)
+			goto out_destroy;
+
+		if (is_mbm_event(mevt->evtid))
+			mon_event_read(&rr, r, d, prgrp, mevt->evtid, true);
+	}
+	kernfs_activate(kn);
+	return 0;
+
+out_destroy:
+	kernfs_remove(kn);
+	return ret;
+}
+
+/*
+ * Add all subdirectories of mon_data for "ctrl_mon" groups
+ * and "monitor" groups with given domain id.
+ */
+static void mkdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
+					   struct rdt_domain *d)
+{
+	struct kernfs_node *parent_kn;
+	struct rdtgroup *prgrp, *crgrp;
+	struct list_head *head;
+
+	list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
+		parent_kn = prgrp->mon.mon_data_kn;
+		mkdir_mondata_subdir(parent_kn, d, r, prgrp);
+
+		head = &prgrp->mon.crdtgrp_list;
+		list_for_each_entry(crgrp, head, mon.crdtgrp_list) {
+			parent_kn = crgrp->mon.mon_data_kn;
+			mkdir_mondata_subdir(parent_kn, d, r, crgrp);
+		}
+	}
+}
+
+static int mkdir_mondata_subdir_alldom(struct kernfs_node *parent_kn,
+				       struct rdt_resource *r,
+				       struct rdtgroup *prgrp)
+{
+	struct rdt_domain *dom;
+	int ret;
+
+	list_for_each_entry(dom, &r->domains, list) {
+		ret = mkdir_mondata_subdir(parent_kn, dom, r, prgrp);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/*
+ * This creates a directory mon_data which contains the monitored data.
+ *
+ * mon_data has one directory for each domain which are named
+ * in the format mon_<domain_name>_<domain_id>. For ex: A mon_data
+ * with L3 domain looks as below:
+ * ./mon_data:
+ * mon_L3_00
+ * mon_L3_01
+ * mon_L3_02
+ * ...
+ *
+ * Each domain directory has one file per event:
+ * ./mon_L3_00/:
+ * llc_occupancy
+ *
+ */
+static int mkdir_mondata_all(struct kernfs_node *parent_kn,
+			     struct rdtgroup *prgrp,
+			     struct kernfs_node **dest_kn)
+{
+	struct rdt_resource *r;
+	struct kernfs_node *kn;
+	int ret;
+
+	/*
+	 * Create the mon_data directory first.
+	 */
+	ret = mongroup_create_dir(parent_kn, prgrp, "mon_data", &kn);
+	if (ret)
+		return ret;
+
+	if (dest_kn)
+		*dest_kn = kn;
+
+	/*
+	 * Create the subdirectories for each domain. Note that all events
+	 * in a domain like L3 are grouped into a resource whose domain is L3
+	 */
+	for_each_mon_capable_rdt_resource(r) {
+		ret = mkdir_mondata_subdir_alldom(kn, r, prgrp);
+		if (ret)
+			goto out_destroy;
+	}
+
+	return 0;
+
+out_destroy:
+	kernfs_remove(kn);
+	return ret;
+}
+
+/**
+ * cbm_ensure_valid - Enforce validity on provided CBM
+ * @_val:	Candidate CBM
+ * @r:		RDT resource to which the CBM belongs
+ *
+ * The provided CBM represents all cache portions available for use. This
+ * may be represented by a bitmap that does not consist of contiguous ones
+ * and thus be an invalid CBM.
+ * Here the provided CBM is forced to be a valid CBM by only considering
+ * the first set of contiguous bits as valid and clearing all bits.
+ * The intention here is to provide a valid default CBM with which a new
+ * resource group is initialized. The user can follow this with a
+ * modification to the CBM if the default does not satisfy the
+ * requirements.
+ */
+static u32 cbm_ensure_valid(u32 _val, struct rdt_resource *r)
+{
+	unsigned int cbm_len = r->cache.cbm_len;
+	unsigned long first_bit, zero_bit;
+	unsigned long val = _val;
+
+	if (!val)
+		return 0;
+
+	first_bit = find_first_bit(&val, cbm_len);
+	zero_bit = find_next_zero_bit(&val, cbm_len, first_bit);
+
+	/* Clear any remaining bits to ensure contiguous region */
+	bitmap_clear(&val, zero_bit, cbm_len - zero_bit);
+	return (u32)val;
+}
+
+/*
+ * Initialize cache resources per RDT domain
+ *
+ * Set the RDT domain up to start off with all usable allocations. That is,
+ * all shareable and unused bits. All-zero CBM is invalid.
+ */
+static int __init_one_rdt_domain(struct rdt_domain *d, struct resctrl_schema *s,
+				 u32 closid)
+{
+	enum resctrl_conf_type peer_type = resctrl_peer_type(s->conf_type);
+	enum resctrl_conf_type t = s->conf_type;
+	struct resctrl_staged_config *cfg;
+	struct rdt_resource *r = s->res;
+	u32 used_b = 0, unused_b = 0;
+	unsigned long tmp_cbm;
+	enum rdtgrp_mode mode;
+	u32 peer_ctl, ctrl_val;
+	int i;
+
+	cfg = &d->staged_config[t];
+	cfg->have_new_ctrl = false;
+	cfg->new_ctrl = r->cache.shareable_bits;
+	used_b = r->cache.shareable_bits;
+	for (i = 0; i < closids_supported(); i++) {
+		if (closid_allocated(i) && i != closid) {
+			mode = rdtgroup_mode_by_closid(i);
+			if (mode == RDT_MODE_PSEUDO_LOCKSETUP)
+				/*
+				 * ctrl values for locksetup aren't relevant
+				 * until the schemata is written, and the mode
+				 * becomes RDT_MODE_PSEUDO_LOCKED.
+				 */
+				continue;
+			/*
+			 * If CDP is active include peer domain's
+			 * usage to ensure there is no overlap
+			 * with an exclusive group.
+			 */
+			if (resctrl_arch_get_cdp_enabled(r->rid))
+				peer_ctl = resctrl_arch_get_config(r, d, i,
+								   peer_type);
+			else
+				peer_ctl = 0;
+			ctrl_val = resctrl_arch_get_config(r, d, i,
+							   s->conf_type);
+			used_b |= ctrl_val | peer_ctl;
+			if (mode == RDT_MODE_SHAREABLE)
+				cfg->new_ctrl |= ctrl_val | peer_ctl;
+		}
+	}
+	if (d->plr && d->plr->cbm > 0)
+		used_b |= d->plr->cbm;
+	unused_b = used_b ^ (BIT_MASK(r->cache.cbm_len) - 1);
+	unused_b &= BIT_MASK(r->cache.cbm_len) - 1;
+	cfg->new_ctrl |= unused_b;
+	/*
+	 * Force the initial CBM to be valid, user can
+	 * modify the CBM based on system availability.
+	 */
+	cfg->new_ctrl = cbm_ensure_valid(cfg->new_ctrl, r);
+	/*
+	 * Assign the u32 CBM to an unsigned long to ensure that
+	 * bitmap_weight() does not access out-of-bound memory.
+	 */
+	tmp_cbm = cfg->new_ctrl;
+	if (bitmap_weight(&tmp_cbm, r->cache.cbm_len) < r->cache.min_cbm_bits) {
+		rdt_last_cmd_printf("No space on %s:%d\n", s->name, d->id);
+		return -ENOSPC;
+	}
+	cfg->have_new_ctrl = true;
+
+	return 0;
+}
+
+/*
+ * Initialize cache resources with default values.
+ *
+ * A new RDT group is being created on an allocation capable (CAT)
+ * supporting system. Set this group up to start off with all usable
+ * allocations.
+ *
+ * If there are no more shareable bits available on any domain then
+ * the entire allocation will fail.
+ */
+static int rdtgroup_init_cat(struct resctrl_schema *s, u32 closid)
+{
+	struct rdt_domain *d;
+	int ret;
+
+	list_for_each_entry(d, &s->res->domains, list) {
+		ret = __init_one_rdt_domain(d, s, closid);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+/* Initialize MBA resource with default values. */
+static void rdtgroup_init_mba(struct rdt_resource *r, u32 closid)
+{
+	struct resctrl_staged_config *cfg;
+	struct rdt_domain *d;
+
+	list_for_each_entry(d, &r->domains, list) {
+		if (is_mba_sc(r)) {
+			d->mbps_val[closid] = MBA_MAX_MBPS;
+			continue;
+		}
+
+		cfg = &d->staged_config[CDP_NONE];
+		cfg->new_ctrl = r->default_ctrl;
+		cfg->have_new_ctrl = true;
+	}
+}
+
+/* Initialize the RDT group's allocations. */
+static int rdtgroup_init_alloc(struct rdtgroup *rdtgrp)
+{
+	struct resctrl_schema *s;
+	struct rdt_resource *r;
+	int ret = 0;
+
+	rdt_staged_configs_clear();
+
+	list_for_each_entry(s, &resctrl_schema_all, list) {
+		r = s->res;
+		if (r->rid == RDT_RESOURCE_MBA ||
+		    r->rid == RDT_RESOURCE_SMBA) {
+			rdtgroup_init_mba(r, rdtgrp->closid);
+			if (is_mba_sc(r))
+				continue;
+		} else {
+			ret = rdtgroup_init_cat(s, rdtgrp->closid);
+			if (ret < 0)
+				goto out;
+		}
+
+		ret = resctrl_arch_update_domains(r, rdtgrp->closid);
+		if (ret < 0) {
+			rdt_last_cmd_puts("Failed to initialize allocations\n");
+			goto out;
+		}
+
+	}
+
+	rdtgrp->mode = RDT_MODE_SHAREABLE;
+
+out:
+	rdt_staged_configs_clear();
+	return ret;
+}
+
+static int mkdir_rdt_prepare(struct kernfs_node *parent_kn,
+			     const char *name, umode_t mode,
+			     enum rdt_group_type rtype, struct rdtgroup **r)
+{
+	struct rdtgroup *prdtgrp, *rdtgrp;
+	struct kernfs_node *kn;
+	uint files = 0;
+	int ret;
+
+	prdtgrp = rdtgroup_kn_lock_live(parent_kn);
+	if (!prdtgrp) {
+		ret = -ENODEV;
+		goto out_unlock;
+	}
+
+	if (rtype == RDTMON_GROUP &&
+	    (prdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP ||
+	     prdtgrp->mode == RDT_MODE_PSEUDO_LOCKED)) {
+		ret = -EINVAL;
+		rdt_last_cmd_puts("Pseudo-locking in progress\n");
+		goto out_unlock;
+	}
+
+	/* allocate the rdtgroup. */
+	rdtgrp = kzalloc(sizeof(*rdtgrp), GFP_KERNEL);
+	if (!rdtgrp) {
+		ret = -ENOSPC;
+		rdt_last_cmd_puts("Kernel out of memory\n");
+		goto out_unlock;
+	}
+	*r = rdtgrp;
+	rdtgrp->mon.parent = prdtgrp;
+	rdtgrp->type = rtype;
+	INIT_LIST_HEAD(&rdtgrp->mon.crdtgrp_list);
+
+	/* kernfs creates the directory for rdtgrp */
+	kn = kernfs_create_dir(parent_kn, name, mode, rdtgrp);
+	if (IS_ERR(kn)) {
+		ret = PTR_ERR(kn);
+		rdt_last_cmd_puts("kernfs create error\n");
+		goto out_free_rgrp;
+	}
+	rdtgrp->kn = kn;
+
+	/*
+	 * kernfs_remove() will drop the reference count on "kn" which
+	 * will free it. But we still need it to stick around for the
+	 * rdtgroup_kn_unlock(kn) call. Take one extra reference here,
+	 * which will be dropped by kernfs_put() in rdtgroup_remove().
+	 */
+	kernfs_get(kn);
+
+	ret = rdtgroup_kn_set_ugid(kn);
+	if (ret) {
+		rdt_last_cmd_puts("kernfs perm error\n");
+		goto out_destroy;
+	}
+
+	files = RFTYPE_BASE | BIT(RF_CTRLSHIFT + rtype);
+	ret = rdtgroup_add_files(kn, files);
+	if (ret) {
+		rdt_last_cmd_puts("kernfs fill error\n");
+		goto out_destroy;
+	}
+
+	if (rdt_mon_capable) {
+		ret = alloc_rmid();
+		if (ret < 0) {
+			rdt_last_cmd_puts("Out of RMIDs\n");
+			goto out_destroy;
+		}
+		rdtgrp->mon.rmid = ret;
+
+		ret = mkdir_mondata_all(kn, rdtgrp, &rdtgrp->mon.mon_data_kn);
+		if (ret) {
+			rdt_last_cmd_puts("kernfs subdir error\n");
+			goto out_idfree;
+		}
+	}
+	kernfs_activate(kn);
+
+	/*
+	 * The caller unlocks the parent_kn upon success.
+	 */
+	return 0;
+
+out_idfree:
+	free_rmid(rdtgrp->mon.rmid);
+out_destroy:
+	kernfs_put(rdtgrp->kn);
+	kernfs_remove(rdtgrp->kn);
+out_free_rgrp:
+	kfree(rdtgrp);
+out_unlock:
+	rdtgroup_kn_unlock(parent_kn);
+	return ret;
+}
+
+static void mkdir_rdt_prepare_clean(struct rdtgroup *rgrp)
+{
+	kernfs_remove(rgrp->kn);
+	free_rmid(rgrp->mon.rmid);
+	rdtgroup_remove(rgrp);
+}
+
+/*
+ * Create a monitor group under "mon_groups" directory of a control
+ * and monitor group(ctrl_mon). This is a resource group
+ * to monitor a subset of tasks and cpus in its parent ctrl_mon group.
+ */
+static int rdtgroup_mkdir_mon(struct kernfs_node *parent_kn,
+			      const char *name, umode_t mode)
+{
+	struct rdtgroup *rdtgrp, *prgrp;
+	int ret;
+
+	ret = mkdir_rdt_prepare(parent_kn, name, mode, RDTMON_GROUP, &rdtgrp);
+	if (ret)
+		return ret;
+
+	prgrp = rdtgrp->mon.parent;
+	rdtgrp->closid = prgrp->closid;
+
+	/*
+	 * Add the rdtgrp to the list of rdtgrps the parent
+	 * ctrl_mon group has to track.
+	 */
+	list_add_tail(&rdtgrp->mon.crdtgrp_list, &prgrp->mon.crdtgrp_list);
+
+	rdtgroup_kn_unlock(parent_kn);
+	return ret;
+}
+
+/*
+ * These are rdtgroups created under the root directory. Can be used
+ * to allocate and monitor resources.
+ */
+static int rdtgroup_mkdir_ctrl_mon(struct kernfs_node *parent_kn,
+				   const char *name, umode_t mode)
+{
+	struct rdtgroup *rdtgrp;
+	struct kernfs_node *kn;
+	u32 closid;
+	int ret;
+
+	ret = mkdir_rdt_prepare(parent_kn, name, mode, RDTCTRL_GROUP, &rdtgrp);
+	if (ret)
+		return ret;
+
+	kn = rdtgrp->kn;
+	ret = closid_alloc();
+	if (ret < 0) {
+		rdt_last_cmd_puts("Out of CLOSIDs\n");
+		goto out_common_fail;
+	}
+	closid = ret;
+	ret = 0;
+
+	rdtgrp->closid = closid;
+	ret = rdtgroup_init_alloc(rdtgrp);
+	if (ret < 0)
+		goto out_id_free;
+
+	list_add(&rdtgrp->rdtgroup_list, &rdt_all_groups);
+
+	if (rdt_mon_capable) {
+		/*
+		 * Create an empty mon_groups directory to hold the subset
+		 * of tasks and cpus to monitor.
+		 */
+		ret = mongroup_create_dir(kn, rdtgrp, "mon_groups", NULL);
+		if (ret) {
+			rdt_last_cmd_puts("kernfs subdir error\n");
+			goto out_del_list;
+		}
+	}
+
+	goto out_unlock;
+
+out_del_list:
+	list_del(&rdtgrp->rdtgroup_list);
+out_id_free:
+	closid_free(closid);
+out_common_fail:
+	mkdir_rdt_prepare_clean(rdtgrp);
+out_unlock:
+	rdtgroup_kn_unlock(parent_kn);
+	return ret;
+}
+
+/*
+ * We allow creating mon groups only with in a directory called "mon_groups"
+ * which is present in every ctrl_mon group. Check if this is a valid
+ * "mon_groups" directory.
+ *
+ * 1. The directory should be named "mon_groups".
+ * 2. The mon group itself should "not" be named "mon_groups".
+ *   This makes sure "mon_groups" directory always has a ctrl_mon group
+ *   as parent.
+ */
+static bool is_mon_groups(struct kernfs_node *kn, const char *name)
+{
+	return (!strcmp(kn->name, "mon_groups") &&
+		strcmp(name, "mon_groups"));
+}
+
+static int rdtgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
+			  umode_t mode)
+{
+	/* Do not accept '\n' to avoid unparsable situation. */
+	if (strchr(name, '\n'))
+		return -EINVAL;
+
+	/*
+	 * If the parent directory is the root directory and RDT
+	 * allocation is supported, add a control and monitoring
+	 * subdirectory
+	 */
+	if (rdt_alloc_capable && parent_kn == rdtgroup_default.kn)
+		return rdtgroup_mkdir_ctrl_mon(parent_kn, name, mode);
+
+	/*
+	 * If RDT monitoring is supported and the parent directory is a valid
+	 * "mon_groups" directory, add a monitoring subdirectory.
+	 */
+	if (rdt_mon_capable && is_mon_groups(parent_kn, name))
+		return rdtgroup_mkdir_mon(parent_kn, name, mode);
+
+	return -EPERM;
+}
+
+static int rdtgroup_rmdir_mon(struct rdtgroup *rdtgrp, cpumask_var_t tmpmask)
+{
+	struct rdtgroup *prdtgrp = rdtgrp->mon.parent;
+	int cpu;
+
+	/* Give any tasks back to the parent group */
+	rdt_move_group_tasks(rdtgrp, prdtgrp, tmpmask);
+
+	/* Update per cpu rmid of the moved CPUs first */
+	for_each_cpu(cpu, &rdtgrp->cpu_mask)
+		per_cpu(pqr_state.default_rmid, cpu) = prdtgrp->mon.rmid;
+	/*
+	 * Update the MSR on moved CPUs and CPUs which have moved
+	 * task running on them.
+	 */
+	cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask);
+	update_closid_rmid(tmpmask, NULL);
+
+	rdtgrp->flags = RDT_DELETED;
+	free_rmid(rdtgrp->mon.rmid);
+
+	/*
+	 * Remove the rdtgrp from the parent ctrl_mon group's list
+	 */
+	WARN_ON(list_empty(&prdtgrp->mon.crdtgrp_list));
+	list_del(&rdtgrp->mon.crdtgrp_list);
+
+	kernfs_remove(rdtgrp->kn);
+
+	return 0;
+}
+
+static int rdtgroup_ctrl_remove(struct rdtgroup *rdtgrp)
+{
+	rdtgrp->flags = RDT_DELETED;
+	list_del(&rdtgrp->rdtgroup_list);
+
+	kernfs_remove(rdtgrp->kn);
+	return 0;
+}
+
+static int rdtgroup_rmdir_ctrl(struct rdtgroup *rdtgrp, cpumask_var_t tmpmask)
+{
+	int cpu;
+
+	/* Give any tasks back to the default group */
+	rdt_move_group_tasks(rdtgrp, &rdtgroup_default, tmpmask);
+
+	/* Give any CPUs back to the default group */
+	cpumask_or(&rdtgroup_default.cpu_mask,
+		   &rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
+
+	/* Update per cpu closid and rmid of the moved CPUs first */
+	for_each_cpu(cpu, &rdtgrp->cpu_mask) {
+		per_cpu(pqr_state.default_closid, cpu) = rdtgroup_default.closid;
+		per_cpu(pqr_state.default_rmid, cpu) = rdtgroup_default.mon.rmid;
+	}
+
+	/*
+	 * Update the MSR on moved CPUs and CPUs which have moved
+	 * task running on them.
+	 */
+	cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask);
+	update_closid_rmid(tmpmask, NULL);
+
+	closid_free(rdtgrp->closid);
+	free_rmid(rdtgrp->mon.rmid);
+
+	rdtgroup_ctrl_remove(rdtgrp);
+
+	/*
+	 * Free all the child monitor group rmids.
+	 */
+	free_all_child_rdtgrp(rdtgrp);
+
+	return 0;
+}
+
+static int rdtgroup_rmdir(struct kernfs_node *kn)
+{
+	struct kernfs_node *parent_kn = kn->parent;
+	struct rdtgroup *rdtgrp;
+	cpumask_var_t tmpmask;
+	int ret = 0;
+
+	if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL))
+		return -ENOMEM;
+
+	rdtgrp = rdtgroup_kn_lock_live(kn);
+	if (!rdtgrp) {
+		ret = -EPERM;
+		goto out;
+	}
+
+	/*
+	 * If the rdtgroup is a ctrl_mon group and parent directory
+	 * is the root directory, remove the ctrl_mon group.
+	 *
+	 * If the rdtgroup is a mon group and parent directory
+	 * is a valid "mon_groups" directory, remove the mon group.
+	 */
+	if (rdtgrp->type == RDTCTRL_GROUP && parent_kn == rdtgroup_default.kn &&
+	    rdtgrp != &rdtgroup_default) {
+		if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP ||
+		    rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) {
+			ret = rdtgroup_ctrl_remove(rdtgrp);
+		} else {
+			ret = rdtgroup_rmdir_ctrl(rdtgrp, tmpmask);
+		}
+	} else if (rdtgrp->type == RDTMON_GROUP &&
+		 is_mon_groups(parent_kn, kn->name)) {
+		ret = rdtgroup_rmdir_mon(rdtgrp, tmpmask);
+	} else {
+		ret = -EPERM;
+	}
+
+out:
+	rdtgroup_kn_unlock(kn);
+	free_cpumask_var(tmpmask);
+	return ret;
+}
+
+/**
+ * mongrp_reparent() - replace parent CTRL_MON group of a MON group
+ * @rdtgrp:		the MON group whose parent should be replaced
+ * @new_prdtgrp:	replacement parent CTRL_MON group for @rdtgrp
+ * @cpus:		cpumask provided by the caller for use during this call
+ *
+ * Replaces the parent CTRL_MON group for a MON group, resulting in all member
+ * tasks' CLOSID immediately changing to that of the new parent group.
+ * Monitoring data for the group is unaffected by this operation.
+ */
+static void mongrp_reparent(struct rdtgroup *rdtgrp,
+			    struct rdtgroup *new_prdtgrp,
+			    cpumask_var_t cpus)
+{
+	struct rdtgroup *prdtgrp = rdtgrp->mon.parent;
+
+	WARN_ON(rdtgrp->type != RDTMON_GROUP);
+	WARN_ON(new_prdtgrp->type != RDTCTRL_GROUP);
+
+	/* Nothing to do when simply renaming a MON group. */
+	if (prdtgrp == new_prdtgrp)
+		return;
+
+	WARN_ON(list_empty(&prdtgrp->mon.crdtgrp_list));
+	list_move_tail(&rdtgrp->mon.crdtgrp_list,
+		       &new_prdtgrp->mon.crdtgrp_list);
+
+	rdtgrp->mon.parent = new_prdtgrp;
+	rdtgrp->closid = new_prdtgrp->closid;
+
+	/* Propagate updated closid to all tasks in this group. */
+	rdt_move_group_tasks(rdtgrp, rdtgrp, cpus);
+
+	update_closid_rmid(cpus, NULL);
+}
+
+static int rdtgroup_rename(struct kernfs_node *kn,
+			   struct kernfs_node *new_parent, const char *new_name)
+{
+	struct rdtgroup *new_prdtgrp;
+	struct rdtgroup *rdtgrp;
+	cpumask_var_t tmpmask;
+	int ret;
+
+	rdtgrp = kernfs_to_rdtgroup(kn);
+	new_prdtgrp = kernfs_to_rdtgroup(new_parent);
+	if (!rdtgrp || !new_prdtgrp)
+		return -ENOENT;
+
+	/* Release both kernfs active_refs before obtaining rdtgroup mutex. */
+	rdtgroup_kn_get(rdtgrp, kn);
+	rdtgroup_kn_get(new_prdtgrp, new_parent);
+
+	mutex_lock(&rdtgroup_mutex);
+
+	rdt_last_cmd_clear();
+
+	/*
+	 * Don't allow kernfs_to_rdtgroup() to return a parent rdtgroup if
+	 * either kernfs_node is a file.
+	 */
+	if (kernfs_type(kn) != KERNFS_DIR ||
+	    kernfs_type(new_parent) != KERNFS_DIR) {
+		rdt_last_cmd_puts("Source and destination must be directories");
+		ret = -EPERM;
+		goto out;
+	}
+
+	if ((rdtgrp->flags & RDT_DELETED) || (new_prdtgrp->flags & RDT_DELETED)) {
+		ret = -ENOENT;
+		goto out;
+	}
+
+	if (rdtgrp->type != RDTMON_GROUP || !kn->parent ||
+	    !is_mon_groups(kn->parent, kn->name)) {
+		rdt_last_cmd_puts("Source must be a MON group\n");
+		ret = -EPERM;
+		goto out;
+	}
+
+	if (!is_mon_groups(new_parent, new_name)) {
+		rdt_last_cmd_puts("Destination must be a mon_groups subdirectory\n");
+		ret = -EPERM;
+		goto out;
+	}
+
+	/*
+	 * If the MON group is monitoring CPUs, the CPUs must be assigned to the
+	 * current parent CTRL_MON group and therefore cannot be assigned to
+	 * the new parent, making the move illegal.
+	 */
+	if (!cpumask_empty(&rdtgrp->cpu_mask) &&
+	    rdtgrp->mon.parent != new_prdtgrp) {
+		rdt_last_cmd_puts("Cannot move a MON group that monitors CPUs\n");
+		ret = -EPERM;
+		goto out;
+	}
+
+	/*
+	 * Allocate the cpumask for use in mongrp_reparent() to avoid the
+	 * possibility of failing to allocate it after kernfs_rename() has
+	 * succeeded.
+	 */
+	if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL)) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	/*
+	 * Perform all input validation and allocations needed to ensure
+	 * mongrp_reparent() will succeed before calling kernfs_rename(),
+	 * otherwise it would be necessary to revert this call if
+	 * mongrp_reparent() failed.
+	 */
+	ret = kernfs_rename(kn, new_parent, new_name);
+	if (!ret)
+		mongrp_reparent(rdtgrp, new_prdtgrp, tmpmask);
+
+	free_cpumask_var(tmpmask);
+
+out:
+	mutex_unlock(&rdtgroup_mutex);
+	rdtgroup_kn_put(rdtgrp, kn);
+	rdtgroup_kn_put(new_prdtgrp, new_parent);
+	return ret;
+}
+
+static int rdtgroup_show_options(struct seq_file *seq, struct kernfs_root *kf)
+{
+	if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L3))
+		seq_puts(seq, ",cdp");
+
+	if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L2))
+		seq_puts(seq, ",cdpl2");
+
+	if (is_mba_sc(&rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl))
+		seq_puts(seq, ",mba_MBps");
+
+	return 0;
+}
+
+static struct kernfs_syscall_ops rdtgroup_kf_syscall_ops = {
+	.mkdir		= rdtgroup_mkdir,
+	.rmdir		= rdtgroup_rmdir,
+	.rename		= rdtgroup_rename,
+	.show_options	= rdtgroup_show_options,
+};
+
+static int __init rdtgroup_setup_root(void)
+{
+	int ret;
+
+	rdt_root = kernfs_create_root(&rdtgroup_kf_syscall_ops,
+				      KERNFS_ROOT_CREATE_DEACTIVATED |
+				      KERNFS_ROOT_EXTRA_OPEN_PERM_CHECK,
+				      &rdtgroup_default);
+	if (IS_ERR(rdt_root))
+		return PTR_ERR(rdt_root);
+
+	mutex_lock(&rdtgroup_mutex);
+
+	rdtgroup_default.closid = 0;
+	rdtgroup_default.mon.rmid = 0;
+	rdtgroup_default.type = RDTCTRL_GROUP;
+	INIT_LIST_HEAD(&rdtgroup_default.mon.crdtgrp_list);
+
+	list_add(&rdtgroup_default.rdtgroup_list, &rdt_all_groups);
+
+	ret = rdtgroup_add_files(kernfs_root_to_node(rdt_root), RF_CTRL_BASE);
+	if (ret) {
+		kernfs_destroy_root(rdt_root);
+		goto out;
+	}
+
+	rdtgroup_default.kn = kernfs_root_to_node(rdt_root);
+	kernfs_activate(rdtgroup_default.kn);
+
+out:
+	mutex_unlock(&rdtgroup_mutex);
+
+	return ret;
+}
+
+static void domain_destroy_mon_state(struct rdt_domain *d)
+{
+	bitmap_free(d->rmid_busy_llc);
+	kfree(d->mbm_total);
+	kfree(d->mbm_local);
+}
+
+void resctrl_offline_domain(struct rdt_resource *r, struct rdt_domain *d)
+{
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	if (supports_mba_mbps() && r->rid == RDT_RESOURCE_MBA)
+		mba_sc_domain_destroy(r, d);
+
+	if (!r->mon_capable)
+		return;
+
+	/*
+	 * If resctrl is mounted, remove all the
+	 * per domain monitor data directories.
+	 */
+	if (static_branch_unlikely(&rdt_mon_enable_key))
+		rmdir_mondata_subdir_allrdtgrp(r, d->id);
+
+	if (is_mbm_enabled())
+		cancel_delayed_work(&d->mbm_over);
+	if (is_llc_occupancy_enabled() && has_busy_rmid(r, d)) {
+		/*
+		 * When a package is going down, forcefully
+		 * decrement rmid->ebusy. There is no way to know
+		 * that the L3 was flushed and hence may lead to
+		 * incorrect counts in rare scenarios, but leaving
+		 * the RMID as busy creates RMID leaks if the
+		 * package never comes back.
+		 */
+		__check_limbo(d, true);
+		cancel_delayed_work(&d->cqm_limbo);
+	}
+
+	domain_destroy_mon_state(d);
+}
+
+static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_domain *d)
+{
+	size_t tsize;
+
+	if (is_llc_occupancy_enabled()) {
+		d->rmid_busy_llc = bitmap_zalloc(r->num_rmid, GFP_KERNEL);
+		if (!d->rmid_busy_llc)
+			return -ENOMEM;
+	}
+	if (is_mbm_total_enabled()) {
+		tsize = sizeof(*d->mbm_total);
+		d->mbm_total = kcalloc(r->num_rmid, tsize, GFP_KERNEL);
+		if (!d->mbm_total) {
+			bitmap_free(d->rmid_busy_llc);
+			return -ENOMEM;
+		}
+	}
+	if (is_mbm_local_enabled()) {
+		tsize = sizeof(*d->mbm_local);
+		d->mbm_local = kcalloc(r->num_rmid, tsize, GFP_KERNEL);
+		if (!d->mbm_local) {
+			bitmap_free(d->rmid_busy_llc);
+			kfree(d->mbm_total);
+			return -ENOMEM;
+		}
+	}
+
+	return 0;
+}
+
+int resctrl_online_domain(struct rdt_resource *r, struct rdt_domain *d)
+{
+	int err;
+
+	lockdep_assert_held(&rdtgroup_mutex);
+
+	if (supports_mba_mbps() && r->rid == RDT_RESOURCE_MBA)
+		/* RDT_RESOURCE_MBA is never mon_capable */
+		return mba_sc_domain_allocate(r, d);
+
+	if (!r->mon_capable)
+		return 0;
+
+	err = domain_setup_mon_state(r, d);
+	if (err)
+		return err;
+
+	if (is_mbm_enabled()) {
+		INIT_DELAYED_WORK(&d->mbm_over, mbm_handle_overflow);
+		mbm_setup_overflow_handler(d, MBM_OVERFLOW_INTERVAL);
+	}
+
+	if (is_llc_occupancy_enabled())
+		INIT_DELAYED_WORK(&d->cqm_limbo, cqm_handle_limbo);
+
+	/* If resctrl is mounted, add per domain monitor data directories. */
+	if (static_branch_unlikely(&rdt_mon_enable_key))
+		mkdir_mondata_subdir_allrdtgrp(r, d);
+
+	return 0;
+}
+
+/*
+ * rdtgroup_init - rdtgroup initialization
+ *
+ * Setup resctrl file system including set up root, create mount point,
+ * register rdtgroup filesystem, and initialize files under root directory.
+ *
+ * Return: 0 on success or -errno
+ */
+int __init rdtgroup_init(void)
+{
+	int ret = 0;
+
+	seq_buf_init(&last_cmd_status, last_cmd_status_buf,
+		     sizeof(last_cmd_status_buf));
+
+	ret = rdtgroup_setup_root();
+	if (ret)
+		return ret;
+
+	ret = sysfs_create_mount_point(fs_kobj, "resctrl");
+	if (ret)
+		goto cleanup_root;
+
+	ret = register_filesystem(&rdt_fs_type);
+	if (ret)
+		goto cleanup_mountpoint;
+
+	/*
+	 * Adding the resctrl debugfs directory here may not be ideal since
+	 * it would let the resctrl debugfs directory appear on the debugfs
+	 * filesystem before the resctrl filesystem is mounted.
+	 * It may also be ok since that would enable debugging of RDT before
+	 * resctrl is mounted.
+	 * The reason why the debugfs directory is created here and not in
+	 * rdt_get_tree() is because rdt_get_tree() takes rdtgroup_mutex and
+	 * during the debugfs directory creation also &sb->s_type->i_mutex_key
+	 * (the lockdep class of inode->i_rwsem). Other filesystem
+	 * interactions (eg. SyS_getdents) have the lock ordering:
+	 * &sb->s_type->i_mutex_key --> &mm->mmap_lock
+	 * During mmap(), called with &mm->mmap_lock, the rdtgroup_mutex
+	 * is taken, thus creating dependency:
+	 * &mm->mmap_lock --> rdtgroup_mutex for the latter that can cause
+	 * issues considering the other two lock dependencies.
+	 * By creating the debugfs directory here we avoid a dependency
+	 * that may cause deadlock (even though file operations cannot
+	 * occur until the filesystem is mounted, but I do not know how to
+	 * tell lockdep that).
+	 */
+	debugfs_resctrl = debugfs_create_dir("resctrl", NULL);
+
+	return 0;
+
+cleanup_mountpoint:
+	sysfs_remove_mount_point(fs_kobj, "resctrl");
+cleanup_root:
+	kernfs_destroy_root(rdt_root);
+
+	return ret;
+}
+
+void __exit rdtgroup_exit(void)
+{
+	debugfs_remove_recursive(debugfs_resctrl);
+	unregister_filesystem(&rdt_fs_type);
+	sysfs_remove_mount_point(fs_kobj, "resctrl");
+	kernfs_destroy_root(rdt_root);
+}
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
new file mode 100644
index 0000000000..0dad49a09b
--- /dev/null
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -0,0 +1,76 @@
+/*
+ *	Routines to identify additional cpu features that are scattered in
+ *	cpuid space.
+ */
+#include <linux/cpu.h>
+
+#include <asm/memtype.h>
+#include <asm/apic.h>
+#include <asm/processor.h>
+
+#include "cpu.h"
+
+struct cpuid_bit {
+	u16 feature;
+	u8 reg;
+	u8 bit;
+	u32 level;
+	u32 sub_leaf;
+};
+
+/*
+ * Please keep the leaf sorted by cpuid_bit.level for faster search.
+ * X86_FEATURE_MBA is supported by both Intel and AMD. But the CPUID
+ * levels are different and there is a separate entry for each.
+ */
+static const struct cpuid_bit cpuid_bits[] = {
+	{ X86_FEATURE_APERFMPERF,       CPUID_ECX,  0, 0x00000006, 0 },
+	{ X86_FEATURE_EPB,		CPUID_ECX,  3, 0x00000006, 0 },
+	{ X86_FEATURE_INTEL_PPIN,	CPUID_EBX,  0, 0x00000007, 1 },
+	{ X86_FEATURE_RRSBA_CTRL,	CPUID_EDX,  2, 0x00000007, 2 },
+	{ X86_FEATURE_CQM_LLC,		CPUID_EDX,  1, 0x0000000f, 0 },
+	{ X86_FEATURE_CQM_OCCUP_LLC,	CPUID_EDX,  0, 0x0000000f, 1 },
+	{ X86_FEATURE_CQM_MBM_TOTAL,	CPUID_EDX,  1, 0x0000000f, 1 },
+	{ X86_FEATURE_CQM_MBM_LOCAL,	CPUID_EDX,  2, 0x0000000f, 1 },
+	{ X86_FEATURE_CAT_L3,		CPUID_EBX,  1, 0x00000010, 0 },
+	{ X86_FEATURE_CAT_L2,		CPUID_EBX,  2, 0x00000010, 0 },
+	{ X86_FEATURE_CDP_L3,		CPUID_ECX,  2, 0x00000010, 1 },
+	{ X86_FEATURE_CDP_L2,		CPUID_ECX,  2, 0x00000010, 2 },
+	{ X86_FEATURE_MBA,		CPUID_EBX,  3, 0x00000010, 0 },
+	{ X86_FEATURE_PER_THREAD_MBA,	CPUID_ECX,  0, 0x00000010, 3 },
+	{ X86_FEATURE_SGX1,		CPUID_EAX,  0, 0x00000012, 0 },
+	{ X86_FEATURE_SGX2,		CPUID_EAX,  1, 0x00000012, 0 },
+	{ X86_FEATURE_SGX_EDECCSSA,	CPUID_EAX, 11, 0x00000012, 0 },
+	{ X86_FEATURE_HW_PSTATE,	CPUID_EDX,  7, 0x80000007, 0 },
+	{ X86_FEATURE_CPB,		CPUID_EDX,  9, 0x80000007, 0 },
+	{ X86_FEATURE_PROC_FEEDBACK,    CPUID_EDX, 11, 0x80000007, 0 },
+	{ X86_FEATURE_MBA,		CPUID_EBX,  6, 0x80000008, 0 },
+	{ X86_FEATURE_SMBA,		CPUID_EBX,  2, 0x80000020, 0 },
+	{ X86_FEATURE_BMEC,		CPUID_EBX,  3, 0x80000020, 0 },
+	{ X86_FEATURE_PERFMON_V2,	CPUID_EAX,  0, 0x80000022, 0 },
+	{ X86_FEATURE_AMD_LBR_V2,	CPUID_EAX,  1, 0x80000022, 0 },
+	{ 0, 0, 0, 0, 0 }
+};
+
+void init_scattered_cpuid_features(struct cpuinfo_x86 *c)
+{
+	u32 max_level;
+	u32 regs[4];
+	const struct cpuid_bit *cb;
+
+	for (cb = cpuid_bits; cb->feature; cb++) {
+
+		/* Verify that the level is valid */
+		max_level = cpuid_eax(cb->level & 0xffff0000);
+		if (max_level < cb->level ||
+		    max_level > (cb->level | 0xffff))
+			continue;
+
+		cpuid_count(cb->level, cb->sub_leaf, &regs[CPUID_EAX],
+			    &regs[CPUID_EBX], &regs[CPUID_ECX],
+			    &regs[CPUID_EDX]);
+
+		if (regs[cb->reg] & (1 << cb->bit))
+			set_cpu_cap(c, cb->feature);
+	}
+}
diff --git a/arch/x86/kernel/cpu/sgx/Makefile b/arch/x86/kernel/cpu/sgx/Makefile
new file mode 100644
index 0000000000..9c1656779b
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/Makefile
@@ -0,0 +1,6 @@
+obj-y += \
+	driver.o \
+	encl.o \
+	ioctl.o \
+	main.o
+obj-$(CONFIG_X86_SGX_KVM)	+= virt.o
diff --git a/arch/x86/kernel/cpu/sgx/driver.c b/arch/x86/kernel/cpu/sgx/driver.c
new file mode 100644
index 0000000000..262f5fb18d
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/driver.c
@@ -0,0 +1,180 @@
+// SPDX-License-Identifier: GPL-2.0
+/*  Copyright(c) 2016-20 Intel Corporation. */
+
+#include <linux/acpi.h>
+#include <linux/miscdevice.h>
+#include <linux/mman.h>
+#include <linux/security.h>
+#include <linux/suspend.h>
+#include <asm/traps.h>
+#include "driver.h"
+#include "encl.h"
+
+u64 sgx_attributes_reserved_mask;
+u64 sgx_xfrm_reserved_mask = ~0x3;
+u32 sgx_misc_reserved_mask;
+
+static int sgx_open(struct inode *inode, struct file *file)
+{
+	struct sgx_encl *encl;
+	int ret;
+
+	encl = kzalloc(sizeof(*encl), GFP_KERNEL);
+	if (!encl)
+		return -ENOMEM;
+
+	kref_init(&encl->refcount);
+	xa_init(&encl->page_array);
+	mutex_init(&encl->lock);
+	INIT_LIST_HEAD(&encl->va_pages);
+	INIT_LIST_HEAD(&encl->mm_list);
+	spin_lock_init(&encl->mm_lock);
+
+	ret = init_srcu_struct(&encl->srcu);
+	if (ret) {
+		kfree(encl);
+		return ret;
+	}
+
+	file->private_data = encl;
+
+	return 0;
+}
+
+static int sgx_release(struct inode *inode, struct file *file)
+{
+	struct sgx_encl *encl = file->private_data;
+	struct sgx_encl_mm *encl_mm;
+
+	/*
+	 * Drain the remaining mm_list entries. At this point the list contains
+	 * entries for processes, which have closed the enclave file but have
+	 * not exited yet. The processes, which have exited, are gone from the
+	 * list by sgx_mmu_notifier_release().
+	 */
+	for ( ; ; )  {
+		spin_lock(&encl->mm_lock);
+
+		if (list_empty(&encl->mm_list)) {
+			encl_mm = NULL;
+		} else {
+			encl_mm = list_first_entry(&encl->mm_list,
+						   struct sgx_encl_mm, list);
+			list_del_rcu(&encl_mm->list);
+		}
+
+		spin_unlock(&encl->mm_lock);
+
+		/* The enclave is no longer mapped by any mm. */
+		if (!encl_mm)
+			break;
+
+		synchronize_srcu(&encl->srcu);
+		mmu_notifier_unregister(&encl_mm->mmu_notifier, encl_mm->mm);
+		kfree(encl_mm);
+
+		/* 'encl_mm' is gone, put encl_mm->encl reference: */
+		kref_put(&encl->refcount, sgx_encl_release);
+	}
+
+	kref_put(&encl->refcount, sgx_encl_release);
+	return 0;
+}
+
+static int sgx_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct sgx_encl *encl = file->private_data;
+	int ret;
+
+	ret = sgx_encl_may_map(encl, vma->vm_start, vma->vm_end, vma->vm_flags);
+	if (ret)
+		return ret;
+
+	ret = sgx_encl_mm_add(encl, vma->vm_mm);
+	if (ret)
+		return ret;
+
+	vma->vm_ops = &sgx_vm_ops;
+	vm_flags_set(vma, VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP | VM_IO);
+	vma->vm_private_data = encl;
+
+	return 0;
+}
+
+static unsigned long sgx_get_unmapped_area(struct file *file,
+					   unsigned long addr,
+					   unsigned long len,
+					   unsigned long pgoff,
+					   unsigned long flags)
+{
+	if ((flags & MAP_TYPE) == MAP_PRIVATE)
+		return -EINVAL;
+
+	if (flags & MAP_FIXED)
+		return addr;
+
+	return current->mm->get_unmapped_area(file, addr, len, pgoff, flags);
+}
+
+#ifdef CONFIG_COMPAT
+static long sgx_compat_ioctl(struct file *filep, unsigned int cmd,
+			      unsigned long arg)
+{
+	return sgx_ioctl(filep, cmd, arg);
+}
+#endif
+
+static const struct file_operations sgx_encl_fops = {
+	.owner			= THIS_MODULE,
+	.open			= sgx_open,
+	.release		= sgx_release,
+	.unlocked_ioctl		= sgx_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl		= sgx_compat_ioctl,
+#endif
+	.mmap			= sgx_mmap,
+	.get_unmapped_area	= sgx_get_unmapped_area,
+};
+
+static struct miscdevice sgx_dev_enclave = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = "sgx_enclave",
+	.nodename = "sgx_enclave",
+	.fops = &sgx_encl_fops,
+};
+
+int __init sgx_drv_init(void)
+{
+	unsigned int eax, ebx, ecx, edx;
+	u64 attr_mask;
+	u64 xfrm_mask;
+	int ret;
+
+	if (!cpu_feature_enabled(X86_FEATURE_SGX_LC))
+		return -ENODEV;
+
+	cpuid_count(SGX_CPUID, 0, &eax, &ebx, &ecx, &edx);
+
+	if (!(eax & 1))  {
+		pr_err("SGX disabled: SGX1 instruction support not available.\n");
+		return -ENODEV;
+	}
+
+	sgx_misc_reserved_mask = ~ebx | SGX_MISC_RESERVED_MASK;
+
+	cpuid_count(SGX_CPUID, 1, &eax, &ebx, &ecx, &edx);
+
+	attr_mask = (((u64)ebx) << 32) + (u64)eax;
+	sgx_attributes_reserved_mask = ~attr_mask | SGX_ATTR_RESERVED_MASK;
+
+	if (cpu_feature_enabled(X86_FEATURE_OSXSAVE)) {
+		xfrm_mask = (((u64)edx) << 32) + (u64)ecx;
+		sgx_xfrm_reserved_mask = ~xfrm_mask;
+	}
+
+	ret = misc_register(&sgx_dev_enclave);
+	if (ret)
+		return ret;
+
+	return 0;
+}
diff --git a/arch/x86/kernel/cpu/sgx/driver.h b/arch/x86/kernel/cpu/sgx/driver.h
new file mode 100644
index 0000000000..4eddb4d571
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/driver.h
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ARCH_SGX_DRIVER_H__
+#define __ARCH_SGX_DRIVER_H__
+
+#include <crypto/hash.h>
+#include <linux/kref.h>
+#include <linux/mmu_notifier.h>
+#include <linux/radix-tree.h>
+#include <linux/rwsem.h>
+#include <linux/sched.h>
+#include <linux/workqueue.h>
+#include <uapi/asm/sgx.h>
+#include "sgx.h"
+
+#define SGX_EINIT_SPIN_COUNT	20
+#define SGX_EINIT_SLEEP_COUNT	50
+#define SGX_EINIT_SLEEP_TIME	20
+
+extern u64 sgx_attributes_reserved_mask;
+extern u64 sgx_xfrm_reserved_mask;
+extern u32 sgx_misc_reserved_mask;
+
+extern const struct file_operations sgx_provision_fops;
+
+long sgx_ioctl(struct file *filep, unsigned int cmd, unsigned long arg);
+
+int sgx_drv_init(void);
+
+#endif /* __ARCH_X86_SGX_DRIVER_H__ */
diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c
new file mode 100644
index 0000000000..279148e724
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/encl.c
@@ -0,0 +1,1325 @@
+// SPDX-License-Identifier: GPL-2.0
+/*  Copyright(c) 2016-20 Intel Corporation. */
+
+#include <linux/lockdep.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/shmem_fs.h>
+#include <linux/suspend.h>
+#include <linux/sched/mm.h>
+#include <asm/sgx.h>
+#include "encl.h"
+#include "encls.h"
+#include "sgx.h"
+
+static int sgx_encl_lookup_backing(struct sgx_encl *encl, unsigned long page_index,
+			    struct sgx_backing *backing);
+
+#define PCMDS_PER_PAGE (PAGE_SIZE / sizeof(struct sgx_pcmd))
+/*
+ * 32 PCMD entries share a PCMD page. PCMD_FIRST_MASK is used to
+ * determine the page index associated with the first PCMD entry
+ * within a PCMD page.
+ */
+#define PCMD_FIRST_MASK GENMASK(4, 0)
+
+/**
+ * reclaimer_writing_to_pcmd() - Query if any enclave page associated with
+ *                               a PCMD page is in process of being reclaimed.
+ * @encl:        Enclave to which PCMD page belongs
+ * @start_addr:  Address of enclave page using first entry within the PCMD page
+ *
+ * When an enclave page is reclaimed some Paging Crypto MetaData (PCMD) is
+ * stored. The PCMD data of a reclaimed enclave page contains enough
+ * information for the processor to verify the page at the time
+ * it is loaded back into the Enclave Page Cache (EPC).
+ *
+ * The backing storage to which enclave pages are reclaimed is laid out as
+ * follows:
+ * Encrypted enclave pages:SECS page:PCMD pages
+ *
+ * Each PCMD page contains the PCMD metadata of
+ * PAGE_SIZE/sizeof(struct sgx_pcmd) enclave pages.
+ *
+ * A PCMD page can only be truncated if it is (a) empty, and (b) not in the
+ * process of getting data (and thus soon being non-empty). (b) is tested with
+ * a check if an enclave page sharing the PCMD page is in the process of being
+ * reclaimed.
+ *
+ * The reclaimer sets the SGX_ENCL_PAGE_BEING_RECLAIMED flag when it
+ * intends to reclaim that enclave page - it means that the PCMD page
+ * associated with that enclave page is about to get some data and thus
+ * even if the PCMD page is empty, it should not be truncated.
+ *
+ * Context: Enclave mutex (&sgx_encl->lock) must be held.
+ * Return: 1 if the reclaimer is about to write to the PCMD page
+ *         0 if the reclaimer has no intention to write to the PCMD page
+ */
+static int reclaimer_writing_to_pcmd(struct sgx_encl *encl,
+				     unsigned long start_addr)
+{
+	int reclaimed = 0;
+	int i;
+
+	/*
+	 * PCMD_FIRST_MASK is based on number of PCMD entries within
+	 * PCMD page being 32.
+	 */
+	BUILD_BUG_ON(PCMDS_PER_PAGE != 32);
+
+	for (i = 0; i < PCMDS_PER_PAGE; i++) {
+		struct sgx_encl_page *entry;
+		unsigned long addr;
+
+		addr = start_addr + i * PAGE_SIZE;
+
+		/*
+		 * Stop when reaching the SECS page - it does not
+		 * have a page_array entry and its reclaim is
+		 * started and completed with enclave mutex held so
+		 * it does not use the SGX_ENCL_PAGE_BEING_RECLAIMED
+		 * flag.
+		 */
+		if (addr == encl->base + encl->size)
+			break;
+
+		entry = xa_load(&encl->page_array, PFN_DOWN(addr));
+		if (!entry)
+			continue;
+
+		/*
+		 * VA page slot ID uses same bit as the flag so it is important
+		 * to ensure that the page is not already in backing store.
+		 */
+		if (entry->epc_page &&
+		    (entry->desc & SGX_ENCL_PAGE_BEING_RECLAIMED)) {
+			reclaimed = 1;
+			break;
+		}
+	}
+
+	return reclaimed;
+}
+
+/*
+ * Calculate byte offset of a PCMD struct associated with an enclave page. PCMD's
+ * follow right after the EPC data in the backing storage. In addition to the
+ * visible enclave pages, there's one extra page slot for SECS, before PCMD
+ * structs.
+ */
+static inline pgoff_t sgx_encl_get_backing_page_pcmd_offset(struct sgx_encl *encl,
+							    unsigned long page_index)
+{
+	pgoff_t epc_end_off = encl->size + sizeof(struct sgx_secs);
+
+	return epc_end_off + page_index * sizeof(struct sgx_pcmd);
+}
+
+/*
+ * Free a page from the backing storage in the given page index.
+ */
+static inline void sgx_encl_truncate_backing_page(struct sgx_encl *encl, unsigned long page_index)
+{
+	struct inode *inode = file_inode(encl->backing);
+
+	shmem_truncate_range(inode, PFN_PHYS(page_index), PFN_PHYS(page_index) + PAGE_SIZE - 1);
+}
+
+/*
+ * ELDU: Load an EPC page as unblocked. For more info, see "OS Management of EPC
+ * Pages" in the SDM.
+ */
+static int __sgx_encl_eldu(struct sgx_encl_page *encl_page,
+			   struct sgx_epc_page *epc_page,
+			   struct sgx_epc_page *secs_page)
+{
+	unsigned long va_offset = encl_page->desc & SGX_ENCL_PAGE_VA_OFFSET_MASK;
+	struct sgx_encl *encl = encl_page->encl;
+	pgoff_t page_index, page_pcmd_off;
+	unsigned long pcmd_first_page;
+	struct sgx_pageinfo pginfo;
+	struct sgx_backing b;
+	bool pcmd_page_empty;
+	u8 *pcmd_page;
+	int ret;
+
+	if (secs_page)
+		page_index = PFN_DOWN(encl_page->desc - encl_page->encl->base);
+	else
+		page_index = PFN_DOWN(encl->size);
+
+	/*
+	 * Address of enclave page using the first entry within the PCMD page.
+	 */
+	pcmd_first_page = PFN_PHYS(page_index & ~PCMD_FIRST_MASK) + encl->base;
+
+	page_pcmd_off = sgx_encl_get_backing_page_pcmd_offset(encl, page_index);
+
+	ret = sgx_encl_lookup_backing(encl, page_index, &b);
+	if (ret)
+		return ret;
+
+	pginfo.addr = encl_page->desc & PAGE_MASK;
+	pginfo.contents = (unsigned long)kmap_local_page(b.contents);
+	pcmd_page = kmap_local_page(b.pcmd);
+	pginfo.metadata = (unsigned long)pcmd_page + b.pcmd_offset;
+
+	if (secs_page)
+		pginfo.secs = (u64)sgx_get_epc_virt_addr(secs_page);
+	else
+		pginfo.secs = 0;
+
+	ret = __eldu(&pginfo, sgx_get_epc_virt_addr(epc_page),
+		     sgx_get_epc_virt_addr(encl_page->va_page->epc_page) + va_offset);
+	if (ret) {
+		if (encls_failed(ret))
+			ENCLS_WARN(ret, "ELDU");
+
+		ret = -EFAULT;
+	}
+
+	memset(pcmd_page + b.pcmd_offset, 0, sizeof(struct sgx_pcmd));
+	set_page_dirty(b.pcmd);
+
+	/*
+	 * The area for the PCMD in the page was zeroed above.  Check if the
+	 * whole page is now empty meaning that all PCMD's have been zeroed:
+	 */
+	pcmd_page_empty = !memchr_inv(pcmd_page, 0, PAGE_SIZE);
+
+	kunmap_local(pcmd_page);
+	kunmap_local((void *)(unsigned long)pginfo.contents);
+
+	get_page(b.pcmd);
+	sgx_encl_put_backing(&b);
+
+	sgx_encl_truncate_backing_page(encl, page_index);
+
+	if (pcmd_page_empty && !reclaimer_writing_to_pcmd(encl, pcmd_first_page)) {
+		sgx_encl_truncate_backing_page(encl, PFN_DOWN(page_pcmd_off));
+		pcmd_page = kmap_local_page(b.pcmd);
+		if (memchr_inv(pcmd_page, 0, PAGE_SIZE))
+			pr_warn("PCMD page not empty after truncate.\n");
+		kunmap_local(pcmd_page);
+	}
+
+	put_page(b.pcmd);
+
+	return ret;
+}
+
+static struct sgx_epc_page *sgx_encl_eldu(struct sgx_encl_page *encl_page,
+					  struct sgx_epc_page *secs_page)
+{
+
+	unsigned long va_offset = encl_page->desc & SGX_ENCL_PAGE_VA_OFFSET_MASK;
+	struct sgx_encl *encl = encl_page->encl;
+	struct sgx_epc_page *epc_page;
+	int ret;
+
+	epc_page = sgx_alloc_epc_page(encl_page, false);
+	if (IS_ERR(epc_page))
+		return epc_page;
+
+	ret = __sgx_encl_eldu(encl_page, epc_page, secs_page);
+	if (ret) {
+		sgx_encl_free_epc_page(epc_page);
+		return ERR_PTR(ret);
+	}
+
+	sgx_free_va_slot(encl_page->va_page, va_offset);
+	list_move(&encl_page->va_page->list, &encl->va_pages);
+	encl_page->desc &= ~SGX_ENCL_PAGE_VA_OFFSET_MASK;
+	encl_page->epc_page = epc_page;
+
+	return epc_page;
+}
+
+/*
+ * Ensure the SECS page is not swapped out.  Must be called with encl->lock
+ * to protect the enclave states including SECS and ensure the SECS page is
+ * not swapped out again while being used.
+ */
+static struct sgx_epc_page *sgx_encl_load_secs(struct sgx_encl *encl)
+{
+	struct sgx_epc_page *epc_page = encl->secs.epc_page;
+
+	if (!epc_page)
+		epc_page = sgx_encl_eldu(&encl->secs, NULL);
+
+	return epc_page;
+}
+
+static struct sgx_encl_page *__sgx_encl_load_page(struct sgx_encl *encl,
+						  struct sgx_encl_page *entry)
+{
+	struct sgx_epc_page *epc_page;
+
+	/* Entry successfully located. */
+	if (entry->epc_page) {
+		if (entry->desc & SGX_ENCL_PAGE_BEING_RECLAIMED)
+			return ERR_PTR(-EBUSY);
+
+		return entry;
+	}
+
+	epc_page = sgx_encl_load_secs(encl);
+	if (IS_ERR(epc_page))
+		return ERR_CAST(epc_page);
+
+	epc_page = sgx_encl_eldu(entry, encl->secs.epc_page);
+	if (IS_ERR(epc_page))
+		return ERR_CAST(epc_page);
+
+	encl->secs_child_cnt++;
+	sgx_mark_page_reclaimable(entry->epc_page);
+
+	return entry;
+}
+
+static struct sgx_encl_page *sgx_encl_load_page_in_vma(struct sgx_encl *encl,
+						       unsigned long addr,
+						       unsigned long vm_flags)
+{
+	unsigned long vm_prot_bits = vm_flags & VM_ACCESS_FLAGS;
+	struct sgx_encl_page *entry;
+
+	entry = xa_load(&encl->page_array, PFN_DOWN(addr));
+	if (!entry)
+		return ERR_PTR(-EFAULT);
+
+	/*
+	 * Verify that the page has equal or higher build time
+	 * permissions than the VMA permissions (i.e. the subset of {VM_READ,
+	 * VM_WRITE, VM_EXECUTE} in vma->vm_flags).
+	 */
+	if ((entry->vm_max_prot_bits & vm_prot_bits) != vm_prot_bits)
+		return ERR_PTR(-EFAULT);
+
+	return __sgx_encl_load_page(encl, entry);
+}
+
+struct sgx_encl_page *sgx_encl_load_page(struct sgx_encl *encl,
+					 unsigned long addr)
+{
+	struct sgx_encl_page *entry;
+
+	entry = xa_load(&encl->page_array, PFN_DOWN(addr));
+	if (!entry)
+		return ERR_PTR(-EFAULT);
+
+	return __sgx_encl_load_page(encl, entry);
+}
+
+/**
+ * sgx_encl_eaug_page() - Dynamically add page to initialized enclave
+ * @vma:	VMA obtained from fault info from where page is accessed
+ * @encl:	enclave accessing the page
+ * @addr:	address that triggered the page fault
+ *
+ * When an initialized enclave accesses a page with no backing EPC page
+ * on a SGX2 system then the EPC can be added dynamically via the SGX2
+ * ENCLS[EAUG] instruction.
+ *
+ * Returns: Appropriate vm_fault_t: VM_FAULT_NOPAGE when PTE was installed
+ * successfully, VM_FAULT_SIGBUS or VM_FAULT_OOM as error otherwise.
+ */
+static vm_fault_t sgx_encl_eaug_page(struct vm_area_struct *vma,
+				     struct sgx_encl *encl, unsigned long addr)
+{
+	vm_fault_t vmret = VM_FAULT_SIGBUS;
+	struct sgx_pageinfo pginfo = {0};
+	struct sgx_encl_page *encl_page;
+	struct sgx_epc_page *epc_page;
+	struct sgx_va_page *va_page;
+	unsigned long phys_addr;
+	u64 secinfo_flags;
+	int ret;
+
+	if (!test_bit(SGX_ENCL_INITIALIZED, &encl->flags))
+		return VM_FAULT_SIGBUS;
+
+	/*
+	 * Ignore internal permission checking for dynamically added pages.
+	 * They matter only for data added during the pre-initialization
+	 * phase. The enclave decides the permissions by the means of
+	 * EACCEPT, EACCEPTCOPY and EMODPE.
+	 */
+	secinfo_flags = SGX_SECINFO_R | SGX_SECINFO_W | SGX_SECINFO_X;
+	encl_page = sgx_encl_page_alloc(encl, addr - encl->base, secinfo_flags);
+	if (IS_ERR(encl_page))
+		return VM_FAULT_OOM;
+
+	mutex_lock(&encl->lock);
+
+	epc_page = sgx_encl_load_secs(encl);
+	if (IS_ERR(epc_page)) {
+		if (PTR_ERR(epc_page) == -EBUSY)
+			vmret = VM_FAULT_NOPAGE;
+		goto err_out_unlock;
+	}
+
+	epc_page = sgx_alloc_epc_page(encl_page, false);
+	if (IS_ERR(epc_page)) {
+		if (PTR_ERR(epc_page) == -EBUSY)
+			vmret =  VM_FAULT_NOPAGE;
+		goto err_out_unlock;
+	}
+
+	va_page = sgx_encl_grow(encl, false);
+	if (IS_ERR(va_page)) {
+		if (PTR_ERR(va_page) == -EBUSY)
+			vmret = VM_FAULT_NOPAGE;
+		goto err_out_epc;
+	}
+
+	if (va_page)
+		list_add(&va_page->list, &encl->va_pages);
+
+	ret = xa_insert(&encl->page_array, PFN_DOWN(encl_page->desc),
+			encl_page, GFP_KERNEL);
+	/*
+	 * If ret == -EBUSY then page was created in another flow while
+	 * running without encl->lock
+	 */
+	if (ret)
+		goto err_out_shrink;
+
+	pginfo.secs = (unsigned long)sgx_get_epc_virt_addr(encl->secs.epc_page);
+	pginfo.addr = encl_page->desc & PAGE_MASK;
+	pginfo.metadata = 0;
+
+	ret = __eaug(&pginfo, sgx_get_epc_virt_addr(epc_page));
+	if (ret)
+		goto err_out;
+
+	encl_page->encl = encl;
+	encl_page->epc_page = epc_page;
+	encl_page->type = SGX_PAGE_TYPE_REG;
+	encl->secs_child_cnt++;
+
+	sgx_mark_page_reclaimable(encl_page->epc_page);
+
+	phys_addr = sgx_get_epc_phys_addr(epc_page);
+	/*
+	 * Do not undo everything when creating PTE entry fails - next #PF
+	 * would find page ready for a PTE.
+	 */
+	vmret = vmf_insert_pfn(vma, addr, PFN_DOWN(phys_addr));
+	if (vmret != VM_FAULT_NOPAGE) {
+		mutex_unlock(&encl->lock);
+		return VM_FAULT_SIGBUS;
+	}
+	mutex_unlock(&encl->lock);
+	return VM_FAULT_NOPAGE;
+
+err_out:
+	xa_erase(&encl->page_array, PFN_DOWN(encl_page->desc));
+
+err_out_shrink:
+	sgx_encl_shrink(encl, va_page);
+err_out_epc:
+	sgx_encl_free_epc_page(epc_page);
+err_out_unlock:
+	mutex_unlock(&encl->lock);
+	kfree(encl_page);
+
+	return vmret;
+}
+
+static vm_fault_t sgx_vma_fault(struct vm_fault *vmf)
+{
+	unsigned long addr = (unsigned long)vmf->address;
+	struct vm_area_struct *vma = vmf->vma;
+	struct sgx_encl_page *entry;
+	unsigned long phys_addr;
+	struct sgx_encl *encl;
+	vm_fault_t ret;
+
+	encl = vma->vm_private_data;
+
+	/*
+	 * It's very unlikely but possible that allocating memory for the
+	 * mm_list entry of a forked process failed in sgx_vma_open(). When
+	 * this happens, vm_private_data is set to NULL.
+	 */
+	if (unlikely(!encl))
+		return VM_FAULT_SIGBUS;
+
+	/*
+	 * The page_array keeps track of all enclave pages, whether they
+	 * are swapped out or not. If there is no entry for this page and
+	 * the system supports SGX2 then it is possible to dynamically add
+	 * a new enclave page. This is only possible for an initialized
+	 * enclave that will be checked for right away.
+	 */
+	if (cpu_feature_enabled(X86_FEATURE_SGX2) &&
+	    (!xa_load(&encl->page_array, PFN_DOWN(addr))))
+		return sgx_encl_eaug_page(vma, encl, addr);
+
+	mutex_lock(&encl->lock);
+
+	entry = sgx_encl_load_page_in_vma(encl, addr, vma->vm_flags);
+	if (IS_ERR(entry)) {
+		mutex_unlock(&encl->lock);
+
+		if (PTR_ERR(entry) == -EBUSY)
+			return VM_FAULT_NOPAGE;
+
+		return VM_FAULT_SIGBUS;
+	}
+
+	phys_addr = sgx_get_epc_phys_addr(entry->epc_page);
+
+	ret = vmf_insert_pfn(vma, addr, PFN_DOWN(phys_addr));
+	if (ret != VM_FAULT_NOPAGE) {
+		mutex_unlock(&encl->lock);
+
+		return VM_FAULT_SIGBUS;
+	}
+
+	sgx_encl_test_and_clear_young(vma->vm_mm, entry);
+	mutex_unlock(&encl->lock);
+
+	return VM_FAULT_NOPAGE;
+}
+
+static void sgx_vma_open(struct vm_area_struct *vma)
+{
+	struct sgx_encl *encl = vma->vm_private_data;
+
+	/*
+	 * It's possible but unlikely that vm_private_data is NULL. This can
+	 * happen in a grandchild of a process, when sgx_encl_mm_add() had
+	 * failed to allocate memory in this callback.
+	 */
+	if (unlikely(!encl))
+		return;
+
+	if (sgx_encl_mm_add(encl, vma->vm_mm))
+		vma->vm_private_data = NULL;
+}
+
+
+/**
+ * sgx_encl_may_map() - Check if a requested VMA mapping is allowed
+ * @encl:		an enclave pointer
+ * @start:		lower bound of the address range, inclusive
+ * @end:		upper bound of the address range, exclusive
+ * @vm_flags:		VMA flags
+ *
+ * Iterate through the enclave pages contained within [@start, @end) to verify
+ * that the permissions requested by a subset of {VM_READ, VM_WRITE, VM_EXEC}
+ * do not contain any permissions that are not contained in the build time
+ * permissions of any of the enclave pages within the given address range.
+ *
+ * An enclave creator must declare the strongest permissions that will be
+ * needed for each enclave page. This ensures that mappings have the identical
+ * or weaker permissions than the earlier declared permissions.
+ *
+ * Return: 0 on success, -EACCES otherwise
+ */
+int sgx_encl_may_map(struct sgx_encl *encl, unsigned long start,
+		     unsigned long end, unsigned long vm_flags)
+{
+	unsigned long vm_prot_bits = vm_flags & VM_ACCESS_FLAGS;
+	struct sgx_encl_page *page;
+	unsigned long count = 0;
+	int ret = 0;
+
+	XA_STATE(xas, &encl->page_array, PFN_DOWN(start));
+
+	/* Disallow mapping outside enclave's address range. */
+	if (test_bit(SGX_ENCL_INITIALIZED, &encl->flags) &&
+	    (start < encl->base || end > encl->base + encl->size))
+		return -EACCES;
+
+	/*
+	 * Disallow READ_IMPLIES_EXEC tasks as their VMA permissions might
+	 * conflict with the enclave page permissions.
+	 */
+	if (current->personality & READ_IMPLIES_EXEC)
+		return -EACCES;
+
+	mutex_lock(&encl->lock);
+	xas_lock(&xas);
+	xas_for_each(&xas, page, PFN_DOWN(end - 1)) {
+		if (~page->vm_max_prot_bits & vm_prot_bits) {
+			ret = -EACCES;
+			break;
+		}
+
+		/* Reschedule on every XA_CHECK_SCHED iteration. */
+		if (!(++count % XA_CHECK_SCHED)) {
+			xas_pause(&xas);
+			xas_unlock(&xas);
+			mutex_unlock(&encl->lock);
+
+			cond_resched();
+
+			mutex_lock(&encl->lock);
+			xas_lock(&xas);
+		}
+	}
+	xas_unlock(&xas);
+	mutex_unlock(&encl->lock);
+
+	return ret;
+}
+
+static int sgx_vma_mprotect(struct vm_area_struct *vma, unsigned long start,
+			    unsigned long end, unsigned long newflags)
+{
+	return sgx_encl_may_map(vma->vm_private_data, start, end, newflags);
+}
+
+static int sgx_encl_debug_read(struct sgx_encl *encl, struct sgx_encl_page *page,
+			       unsigned long addr, void *data)
+{
+	unsigned long offset = addr & ~PAGE_MASK;
+	int ret;
+
+
+	ret = __edbgrd(sgx_get_epc_virt_addr(page->epc_page) + offset, data);
+	if (ret)
+		return -EIO;
+
+	return 0;
+}
+
+static int sgx_encl_debug_write(struct sgx_encl *encl, struct sgx_encl_page *page,
+				unsigned long addr, void *data)
+{
+	unsigned long offset = addr & ~PAGE_MASK;
+	int ret;
+
+	ret = __edbgwr(sgx_get_epc_virt_addr(page->epc_page) + offset, data);
+	if (ret)
+		return -EIO;
+
+	return 0;
+}
+
+/*
+ * Load an enclave page to EPC if required, and take encl->lock.
+ */
+static struct sgx_encl_page *sgx_encl_reserve_page(struct sgx_encl *encl,
+						   unsigned long addr,
+						   unsigned long vm_flags)
+{
+	struct sgx_encl_page *entry;
+
+	for ( ; ; ) {
+		mutex_lock(&encl->lock);
+
+		entry = sgx_encl_load_page_in_vma(encl, addr, vm_flags);
+		if (PTR_ERR(entry) != -EBUSY)
+			break;
+
+		mutex_unlock(&encl->lock);
+	}
+
+	if (IS_ERR(entry))
+		mutex_unlock(&encl->lock);
+
+	return entry;
+}
+
+static int sgx_vma_access(struct vm_area_struct *vma, unsigned long addr,
+			  void *buf, int len, int write)
+{
+	struct sgx_encl *encl = vma->vm_private_data;
+	struct sgx_encl_page *entry = NULL;
+	char data[sizeof(unsigned long)];
+	unsigned long align;
+	int offset;
+	int cnt;
+	int ret = 0;
+	int i;
+
+	/*
+	 * If process was forked, VMA is still there but vm_private_data is set
+	 * to NULL.
+	 */
+	if (!encl)
+		return -EFAULT;
+
+	if (!test_bit(SGX_ENCL_DEBUG, &encl->flags))
+		return -EFAULT;
+
+	for (i = 0; i < len; i += cnt) {
+		entry = sgx_encl_reserve_page(encl, (addr + i) & PAGE_MASK,
+					      vma->vm_flags);
+		if (IS_ERR(entry)) {
+			ret = PTR_ERR(entry);
+			break;
+		}
+
+		align = ALIGN_DOWN(addr + i, sizeof(unsigned long));
+		offset = (addr + i) & (sizeof(unsigned long) - 1);
+		cnt = sizeof(unsigned long) - offset;
+		cnt = min(cnt, len - i);
+
+		ret = sgx_encl_debug_read(encl, entry, align, data);
+		if (ret)
+			goto out;
+
+		if (write) {
+			memcpy(data + offset, buf + i, cnt);
+			ret = sgx_encl_debug_write(encl, entry, align, data);
+			if (ret)
+				goto out;
+		} else {
+			memcpy(buf + i, data + offset, cnt);
+		}
+
+out:
+		mutex_unlock(&encl->lock);
+
+		if (ret)
+			break;
+	}
+
+	return ret < 0 ? ret : i;
+}
+
+const struct vm_operations_struct sgx_vm_ops = {
+	.fault = sgx_vma_fault,
+	.mprotect = sgx_vma_mprotect,
+	.open = sgx_vma_open,
+	.access = sgx_vma_access,
+};
+
+/**
+ * sgx_encl_release - Destroy an enclave instance
+ * @ref:	address of a kref inside &sgx_encl
+ *
+ * Used together with kref_put(). Frees all the resources associated with the
+ * enclave and the instance itself.
+ */
+void sgx_encl_release(struct kref *ref)
+{
+	struct sgx_encl *encl = container_of(ref, struct sgx_encl, refcount);
+	unsigned long max_page_index = PFN_DOWN(encl->base + encl->size - 1);
+	struct sgx_va_page *va_page;
+	struct sgx_encl_page *entry;
+	unsigned long count = 0;
+
+	XA_STATE(xas, &encl->page_array, PFN_DOWN(encl->base));
+
+	xas_lock(&xas);
+	xas_for_each(&xas, entry, max_page_index) {
+		if (entry->epc_page) {
+			/*
+			 * The page and its radix tree entry cannot be freed
+			 * if the page is being held by the reclaimer.
+			 */
+			if (sgx_unmark_page_reclaimable(entry->epc_page))
+				continue;
+
+			sgx_encl_free_epc_page(entry->epc_page);
+			encl->secs_child_cnt--;
+			entry->epc_page = NULL;
+		}
+
+		kfree(entry);
+		/*
+		 * Invoke scheduler on every XA_CHECK_SCHED iteration
+		 * to prevent soft lockups.
+		 */
+		if (!(++count % XA_CHECK_SCHED)) {
+			xas_pause(&xas);
+			xas_unlock(&xas);
+
+			cond_resched();
+
+			xas_lock(&xas);
+		}
+	}
+	xas_unlock(&xas);
+
+	xa_destroy(&encl->page_array);
+
+	if (!encl->secs_child_cnt && encl->secs.epc_page) {
+		sgx_encl_free_epc_page(encl->secs.epc_page);
+		encl->secs.epc_page = NULL;
+	}
+
+	while (!list_empty(&encl->va_pages)) {
+		va_page = list_first_entry(&encl->va_pages, struct sgx_va_page,
+					   list);
+		list_del(&va_page->list);
+		sgx_encl_free_epc_page(va_page->epc_page);
+		kfree(va_page);
+	}
+
+	if (encl->backing)
+		fput(encl->backing);
+
+	cleanup_srcu_struct(&encl->srcu);
+
+	WARN_ON_ONCE(!list_empty(&encl->mm_list));
+
+	/* Detect EPC page leak's. */
+	WARN_ON_ONCE(encl->secs_child_cnt);
+	WARN_ON_ONCE(encl->secs.epc_page);
+
+	kfree(encl);
+}
+
+/*
+ * 'mm' is exiting and no longer needs mmu notifications.
+ */
+static void sgx_mmu_notifier_release(struct mmu_notifier *mn,
+				     struct mm_struct *mm)
+{
+	struct sgx_encl_mm *encl_mm = container_of(mn, struct sgx_encl_mm, mmu_notifier);
+	struct sgx_encl_mm *tmp = NULL;
+	bool found = false;
+
+	/*
+	 * The enclave itself can remove encl_mm.  Note, objects can't be moved
+	 * off an RCU protected list, but deletion is ok.
+	 */
+	spin_lock(&encl_mm->encl->mm_lock);
+	list_for_each_entry(tmp, &encl_mm->encl->mm_list, list) {
+		if (tmp == encl_mm) {
+			list_del_rcu(&encl_mm->list);
+			found = true;
+			break;
+		}
+	}
+	spin_unlock(&encl_mm->encl->mm_lock);
+
+	if (found) {
+		synchronize_srcu(&encl_mm->encl->srcu);
+		mmu_notifier_put(mn);
+	}
+}
+
+static void sgx_mmu_notifier_free(struct mmu_notifier *mn)
+{
+	struct sgx_encl_mm *encl_mm = container_of(mn, struct sgx_encl_mm, mmu_notifier);
+
+	/* 'encl_mm' is going away, put encl_mm->encl reference: */
+	kref_put(&encl_mm->encl->refcount, sgx_encl_release);
+
+	kfree(encl_mm);
+}
+
+static const struct mmu_notifier_ops sgx_mmu_notifier_ops = {
+	.release		= sgx_mmu_notifier_release,
+	.free_notifier		= sgx_mmu_notifier_free,
+};
+
+static struct sgx_encl_mm *sgx_encl_find_mm(struct sgx_encl *encl,
+					    struct mm_struct *mm)
+{
+	struct sgx_encl_mm *encl_mm = NULL;
+	struct sgx_encl_mm *tmp;
+	int idx;
+
+	idx = srcu_read_lock(&encl->srcu);
+
+	list_for_each_entry_rcu(tmp, &encl->mm_list, list) {
+		if (tmp->mm == mm) {
+			encl_mm = tmp;
+			break;
+		}
+	}
+
+	srcu_read_unlock(&encl->srcu, idx);
+
+	return encl_mm;
+}
+
+int sgx_encl_mm_add(struct sgx_encl *encl, struct mm_struct *mm)
+{
+	struct sgx_encl_mm *encl_mm;
+	int ret;
+
+	/*
+	 * Even though a single enclave may be mapped into an mm more than once,
+	 * each 'mm' only appears once on encl->mm_list. This is guaranteed by
+	 * holding the mm's mmap lock for write before an mm can be added or
+	 * remove to an encl->mm_list.
+	 */
+	mmap_assert_write_locked(mm);
+
+	/*
+	 * It's possible that an entry already exists in the mm_list, because it
+	 * is removed only on VFS release or process exit.
+	 */
+	if (sgx_encl_find_mm(encl, mm))
+		return 0;
+
+	encl_mm = kzalloc(sizeof(*encl_mm), GFP_KERNEL);
+	if (!encl_mm)
+		return -ENOMEM;
+
+	/* Grab a refcount for the encl_mm->encl reference: */
+	kref_get(&encl->refcount);
+	encl_mm->encl = encl;
+	encl_mm->mm = mm;
+	encl_mm->mmu_notifier.ops = &sgx_mmu_notifier_ops;
+
+	ret = __mmu_notifier_register(&encl_mm->mmu_notifier, mm);
+	if (ret) {
+		kfree(encl_mm);
+		return ret;
+	}
+
+	spin_lock(&encl->mm_lock);
+	list_add_rcu(&encl_mm->list, &encl->mm_list);
+	/* Pairs with smp_rmb() in sgx_zap_enclave_ptes(). */
+	smp_wmb();
+	encl->mm_list_version++;
+	spin_unlock(&encl->mm_lock);
+
+	return 0;
+}
+
+/**
+ * sgx_encl_cpumask() - Query which CPUs might be accessing the enclave
+ * @encl: the enclave
+ *
+ * Some SGX functions require that no cached linear-to-physical address
+ * mappings are present before they can succeed. For example, ENCLS[EWB]
+ * copies a page from the enclave page cache to regular main memory but
+ * it fails if it cannot ensure that there are no cached
+ * linear-to-physical address mappings referring to the page.
+ *
+ * SGX hardware flushes all cached linear-to-physical mappings on a CPU
+ * when an enclave is exited via ENCLU[EEXIT] or an Asynchronous Enclave
+ * Exit (AEX). Exiting an enclave will thus ensure cached linear-to-physical
+ * address mappings are cleared but coordination with the tracking done within
+ * the SGX hardware is needed to support the SGX functions that depend on this
+ * cache clearing.
+ *
+ * When the ENCLS[ETRACK] function is issued on an enclave the hardware
+ * tracks threads operating inside the enclave at that time. The SGX
+ * hardware tracking require that all the identified threads must have
+ * exited the enclave in order to flush the mappings before a function such
+ * as ENCLS[EWB] will be permitted
+ *
+ * The following flow is used to support SGX functions that require that
+ * no cached linear-to-physical address mappings are present:
+ * 1) Execute ENCLS[ETRACK] to initiate hardware tracking.
+ * 2) Use this function (sgx_encl_cpumask()) to query which CPUs might be
+ *    accessing the enclave.
+ * 3) Send IPI to identified CPUs, kicking them out of the enclave and
+ *    thus flushing all locally cached linear-to-physical address mappings.
+ * 4) Execute SGX function.
+ *
+ * Context: It is required to call this function after ENCLS[ETRACK].
+ *          This will ensure that if any new mm appears (racing with
+ *          sgx_encl_mm_add()) then the new mm will enter into the
+ *          enclave with fresh linear-to-physical address mappings.
+ *
+ *          It is required that all IPIs are completed before a new
+ *          ENCLS[ETRACK] is issued so be sure to protect steps 1 to 3
+ *          of the above flow with the enclave's mutex.
+ *
+ * Return: cpumask of CPUs that might be accessing @encl
+ */
+const cpumask_t *sgx_encl_cpumask(struct sgx_encl *encl)
+{
+	cpumask_t *cpumask = &encl->cpumask;
+	struct sgx_encl_mm *encl_mm;
+	int idx;
+
+	cpumask_clear(cpumask);
+
+	idx = srcu_read_lock(&encl->srcu);
+
+	list_for_each_entry_rcu(encl_mm, &encl->mm_list, list) {
+		if (!mmget_not_zero(encl_mm->mm))
+			continue;
+
+		cpumask_or(cpumask, cpumask, mm_cpumask(encl_mm->mm));
+
+		mmput_async(encl_mm->mm);
+	}
+
+	srcu_read_unlock(&encl->srcu, idx);
+
+	return cpumask;
+}
+
+static struct page *sgx_encl_get_backing_page(struct sgx_encl *encl,
+					      pgoff_t index)
+{
+	struct address_space *mapping = encl->backing->f_mapping;
+	gfp_t gfpmask = mapping_gfp_mask(mapping);
+
+	return shmem_read_mapping_page_gfp(mapping, index, gfpmask);
+}
+
+/**
+ * __sgx_encl_get_backing() - Pin the backing storage
+ * @encl:	an enclave pointer
+ * @page_index:	enclave page index
+ * @backing:	data for accessing backing storage for the page
+ *
+ * Pin the backing storage pages for storing the encrypted contents and Paging
+ * Crypto MetaData (PCMD) of an enclave page.
+ *
+ * Return:
+ *   0 on success,
+ *   -errno otherwise.
+ */
+static int __sgx_encl_get_backing(struct sgx_encl *encl, unsigned long page_index,
+			 struct sgx_backing *backing)
+{
+	pgoff_t page_pcmd_off = sgx_encl_get_backing_page_pcmd_offset(encl, page_index);
+	struct page *contents;
+	struct page *pcmd;
+
+	contents = sgx_encl_get_backing_page(encl, page_index);
+	if (IS_ERR(contents))
+		return PTR_ERR(contents);
+
+	pcmd = sgx_encl_get_backing_page(encl, PFN_DOWN(page_pcmd_off));
+	if (IS_ERR(pcmd)) {
+		put_page(contents);
+		return PTR_ERR(pcmd);
+	}
+
+	backing->contents = contents;
+	backing->pcmd = pcmd;
+	backing->pcmd_offset = page_pcmd_off & (PAGE_SIZE - 1);
+
+	return 0;
+}
+
+/*
+ * When called from ksgxd, returns the mem_cgroup of a struct mm stored
+ * in the enclave's mm_list. When not called from ksgxd, just returns
+ * the mem_cgroup of the current task.
+ */
+static struct mem_cgroup *sgx_encl_get_mem_cgroup(struct sgx_encl *encl)
+{
+	struct mem_cgroup *memcg = NULL;
+	struct sgx_encl_mm *encl_mm;
+	int idx;
+
+	/*
+	 * If called from normal task context, return the mem_cgroup
+	 * of the current task's mm. The remainder of the handling is for
+	 * ksgxd.
+	 */
+	if (!current_is_ksgxd())
+		return get_mem_cgroup_from_mm(current->mm);
+
+	/*
+	 * Search the enclave's mm_list to find an mm associated with
+	 * this enclave to charge the allocation to.
+	 */
+	idx = srcu_read_lock(&encl->srcu);
+
+	list_for_each_entry_rcu(encl_mm, &encl->mm_list, list) {
+		if (!mmget_not_zero(encl_mm->mm))
+			continue;
+
+		memcg = get_mem_cgroup_from_mm(encl_mm->mm);
+
+		mmput_async(encl_mm->mm);
+
+		break;
+	}
+
+	srcu_read_unlock(&encl->srcu, idx);
+
+	/*
+	 * In the rare case that there isn't an mm associated with
+	 * the enclave, set memcg to the current active mem_cgroup.
+	 * This will be the root mem_cgroup if there is no active
+	 * mem_cgroup.
+	 */
+	if (!memcg)
+		return get_mem_cgroup_from_mm(NULL);
+
+	return memcg;
+}
+
+/**
+ * sgx_encl_alloc_backing() - create a new backing storage page
+ * @encl:	an enclave pointer
+ * @page_index:	enclave page index
+ * @backing:	data for accessing backing storage for the page
+ *
+ * When called from ksgxd, sets the active memcg from one of the
+ * mms in the enclave's mm_list prior to any backing page allocation,
+ * in order to ensure that shmem page allocations are charged to the
+ * enclave.  Create a backing page for loading data back into an EPC page with
+ * ELDU.  This function takes a reference on a new backing page which
+ * must be dropped with a corresponding call to sgx_encl_put_backing().
+ *
+ * Return:
+ *   0 on success,
+ *   -errno otherwise.
+ */
+int sgx_encl_alloc_backing(struct sgx_encl *encl, unsigned long page_index,
+			   struct sgx_backing *backing)
+{
+	struct mem_cgroup *encl_memcg = sgx_encl_get_mem_cgroup(encl);
+	struct mem_cgroup *memcg = set_active_memcg(encl_memcg);
+	int ret;
+
+	ret = __sgx_encl_get_backing(encl, page_index, backing);
+
+	set_active_memcg(memcg);
+	mem_cgroup_put(encl_memcg);
+
+	return ret;
+}
+
+/**
+ * sgx_encl_lookup_backing() - retrieve an existing backing storage page
+ * @encl:	an enclave pointer
+ * @page_index:	enclave page index
+ * @backing:	data for accessing backing storage for the page
+ *
+ * Retrieve a backing page for loading data back into an EPC page with ELDU.
+ * It is the caller's responsibility to ensure that it is appropriate to use
+ * sgx_encl_lookup_backing() rather than sgx_encl_alloc_backing(). If lookup is
+ * not used correctly, this will cause an allocation which is not accounted for.
+ * This function takes a reference on an existing backing page which must be
+ * dropped with a corresponding call to sgx_encl_put_backing().
+ *
+ * Return:
+ *   0 on success,
+ *   -errno otherwise.
+ */
+static int sgx_encl_lookup_backing(struct sgx_encl *encl, unsigned long page_index,
+			   struct sgx_backing *backing)
+{
+	return __sgx_encl_get_backing(encl, page_index, backing);
+}
+
+/**
+ * sgx_encl_put_backing() - Unpin the backing storage
+ * @backing:	data for accessing backing storage for the page
+ */
+void sgx_encl_put_backing(struct sgx_backing *backing)
+{
+	put_page(backing->pcmd);
+	put_page(backing->contents);
+}
+
+static int sgx_encl_test_and_clear_young_cb(pte_t *ptep, unsigned long addr,
+					    void *data)
+{
+	pte_t pte;
+	int ret;
+
+	ret = pte_young(*ptep);
+	if (ret) {
+		pte = pte_mkold(*ptep);
+		set_pte_at((struct mm_struct *)data, addr, ptep, pte);
+	}
+
+	return ret;
+}
+
+/**
+ * sgx_encl_test_and_clear_young() - Test and reset the accessed bit
+ * @mm:		mm_struct that is checked
+ * @page:	enclave page to be tested for recent access
+ *
+ * Checks the Access (A) bit from the PTE corresponding to the enclave page and
+ * clears it.
+ *
+ * Return: 1 if the page has been recently accessed and 0 if not.
+ */
+int sgx_encl_test_and_clear_young(struct mm_struct *mm,
+				  struct sgx_encl_page *page)
+{
+	unsigned long addr = page->desc & PAGE_MASK;
+	struct sgx_encl *encl = page->encl;
+	struct vm_area_struct *vma;
+	int ret;
+
+	ret = sgx_encl_find(mm, addr, &vma);
+	if (ret)
+		return 0;
+
+	if (encl != vma->vm_private_data)
+		return 0;
+
+	ret = apply_to_page_range(vma->vm_mm, addr, PAGE_SIZE,
+				  sgx_encl_test_and_clear_young_cb, vma->vm_mm);
+	if (ret < 0)
+		return 0;
+
+	return ret;
+}
+
+struct sgx_encl_page *sgx_encl_page_alloc(struct sgx_encl *encl,
+					  unsigned long offset,
+					  u64 secinfo_flags)
+{
+	struct sgx_encl_page *encl_page;
+	unsigned long prot;
+
+	encl_page = kzalloc(sizeof(*encl_page), GFP_KERNEL);
+	if (!encl_page)
+		return ERR_PTR(-ENOMEM);
+
+	encl_page->desc = encl->base + offset;
+	encl_page->encl = encl;
+
+	prot = _calc_vm_trans(secinfo_flags, SGX_SECINFO_R, PROT_READ)  |
+	       _calc_vm_trans(secinfo_flags, SGX_SECINFO_W, PROT_WRITE) |
+	       _calc_vm_trans(secinfo_flags, SGX_SECINFO_X, PROT_EXEC);
+
+	/*
+	 * TCS pages must always RW set for CPU access while the SECINFO
+	 * permissions are *always* zero - the CPU ignores the user provided
+	 * values and silently overwrites them with zero permissions.
+	 */
+	if ((secinfo_flags & SGX_SECINFO_PAGE_TYPE_MASK) == SGX_SECINFO_TCS)
+		prot |= PROT_READ | PROT_WRITE;
+
+	/* Calculate maximum of the VM flags for the page. */
+	encl_page->vm_max_prot_bits = calc_vm_prot_bits(prot, 0);
+
+	return encl_page;
+}
+
+/**
+ * sgx_zap_enclave_ptes() - remove PTEs mapping the address from enclave
+ * @encl: the enclave
+ * @addr: page aligned pointer to single page for which PTEs will be removed
+ *
+ * Multiple VMAs may have an enclave page mapped. Remove the PTE mapping
+ * @addr from each VMA. Ensure that page fault handler is ready to handle
+ * new mappings of @addr before calling this function.
+ */
+void sgx_zap_enclave_ptes(struct sgx_encl *encl, unsigned long addr)
+{
+	unsigned long mm_list_version;
+	struct sgx_encl_mm *encl_mm;
+	struct vm_area_struct *vma;
+	int idx, ret;
+
+	do {
+		mm_list_version = encl->mm_list_version;
+
+		/* Pairs with smp_wmb() in sgx_encl_mm_add(). */
+		smp_rmb();
+
+		idx = srcu_read_lock(&encl->srcu);
+
+		list_for_each_entry_rcu(encl_mm, &encl->mm_list, list) {
+			if (!mmget_not_zero(encl_mm->mm))
+				continue;
+
+			mmap_read_lock(encl_mm->mm);
+
+			ret = sgx_encl_find(encl_mm->mm, addr, &vma);
+			if (!ret && encl == vma->vm_private_data)
+				zap_vma_ptes(vma, addr, PAGE_SIZE);
+
+			mmap_read_unlock(encl_mm->mm);
+
+			mmput_async(encl_mm->mm);
+		}
+
+		srcu_read_unlock(&encl->srcu, idx);
+	} while (unlikely(encl->mm_list_version != mm_list_version));
+}
+
+/**
+ * sgx_alloc_va_page() - Allocate a Version Array (VA) page
+ * @reclaim: Reclaim EPC pages directly if none available. Enclave
+ *           mutex should not be held if this is set.
+ *
+ * Allocate a free EPC page and convert it to a Version Array (VA) page.
+ *
+ * Return:
+ *   a VA page,
+ *   -errno otherwise
+ */
+struct sgx_epc_page *sgx_alloc_va_page(bool reclaim)
+{
+	struct sgx_epc_page *epc_page;
+	int ret;
+
+	epc_page = sgx_alloc_epc_page(NULL, reclaim);
+	if (IS_ERR(epc_page))
+		return ERR_CAST(epc_page);
+
+	ret = __epa(sgx_get_epc_virt_addr(epc_page));
+	if (ret) {
+		WARN_ONCE(1, "EPA returned %d (0x%x)", ret, ret);
+		sgx_encl_free_epc_page(epc_page);
+		return ERR_PTR(-EFAULT);
+	}
+
+	return epc_page;
+}
+
+/**
+ * sgx_alloc_va_slot - allocate a VA slot
+ * @va_page:	a &struct sgx_va_page instance
+ *
+ * Allocates a slot from a &struct sgx_va_page instance.
+ *
+ * Return: offset of the slot inside the VA page
+ */
+unsigned int sgx_alloc_va_slot(struct sgx_va_page *va_page)
+{
+	int slot = find_first_zero_bit(va_page->slots, SGX_VA_SLOT_COUNT);
+
+	if (slot < SGX_VA_SLOT_COUNT)
+		set_bit(slot, va_page->slots);
+
+	return slot << 3;
+}
+
+/**
+ * sgx_free_va_slot - free a VA slot
+ * @va_page:	a &struct sgx_va_page instance
+ * @offset:	offset of the slot inside the VA page
+ *
+ * Frees a slot from a &struct sgx_va_page instance.
+ */
+void sgx_free_va_slot(struct sgx_va_page *va_page, unsigned int offset)
+{
+	clear_bit(offset >> 3, va_page->slots);
+}
+
+/**
+ * sgx_va_page_full - is the VA page full?
+ * @va_page:	a &struct sgx_va_page instance
+ *
+ * Return: true if all slots have been taken
+ */
+bool sgx_va_page_full(struct sgx_va_page *va_page)
+{
+	int slot = find_first_zero_bit(va_page->slots, SGX_VA_SLOT_COUNT);
+
+	return slot == SGX_VA_SLOT_COUNT;
+}
+
+/**
+ * sgx_encl_free_epc_page - free an EPC page assigned to an enclave
+ * @page:	EPC page to be freed
+ *
+ * Free an EPC page assigned to an enclave. It does EREMOVE for the page, and
+ * only upon success, it puts the page back to free page list.  Otherwise, it
+ * gives a WARNING to indicate page is leaked.
+ */
+void sgx_encl_free_epc_page(struct sgx_epc_page *page)
+{
+	int ret;
+
+	WARN_ON_ONCE(page->flags & SGX_EPC_PAGE_RECLAIMER_TRACKED);
+
+	ret = __eremove(sgx_get_epc_virt_addr(page));
+	if (WARN_ONCE(ret, EREMOVE_ERROR_MESSAGE, ret, ret))
+		return;
+
+	sgx_free_epc_page(page);
+}
diff --git a/arch/x86/kernel/cpu/sgx/encl.h b/arch/x86/kernel/cpu/sgx/encl.h
new file mode 100644
index 0000000000..f94ff14c94
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/encl.h
@@ -0,0 +1,129 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/**
+ * Copyright(c) 2016-20 Intel Corporation.
+ *
+ * Contains the software defined data structures for enclaves.
+ */
+#ifndef _X86_ENCL_H
+#define _X86_ENCL_H
+
+#include <linux/cpumask.h>
+#include <linux/kref.h>
+#include <linux/list.h>
+#include <linux/mm_types.h>
+#include <linux/mmu_notifier.h>
+#include <linux/mutex.h>
+#include <linux/notifier.h>
+#include <linux/srcu.h>
+#include <linux/workqueue.h>
+#include <linux/xarray.h>
+#include "sgx.h"
+
+/* 'desc' bits holding the offset in the VA (version array) page. */
+#define SGX_ENCL_PAGE_VA_OFFSET_MASK	GENMASK_ULL(11, 3)
+
+/* 'desc' bit marking that the page is being reclaimed. */
+#define SGX_ENCL_PAGE_BEING_RECLAIMED	BIT(3)
+
+struct sgx_encl_page {
+	unsigned long desc;
+	unsigned long vm_max_prot_bits:8;
+	enum sgx_page_type type:16;
+	struct sgx_epc_page *epc_page;
+	struct sgx_encl *encl;
+	struct sgx_va_page *va_page;
+};
+
+enum sgx_encl_flags {
+	SGX_ENCL_IOCTL		= BIT(0),
+	SGX_ENCL_DEBUG		= BIT(1),
+	SGX_ENCL_CREATED	= BIT(2),
+	SGX_ENCL_INITIALIZED	= BIT(3),
+};
+
+struct sgx_encl_mm {
+	struct sgx_encl *encl;
+	struct mm_struct *mm;
+	struct list_head list;
+	struct mmu_notifier mmu_notifier;
+};
+
+struct sgx_encl {
+	unsigned long base;
+	unsigned long size;
+	unsigned long flags;
+	unsigned int page_cnt;
+	unsigned int secs_child_cnt;
+	struct mutex lock;
+	struct xarray page_array;
+	struct sgx_encl_page secs;
+	unsigned long attributes;
+	unsigned long attributes_mask;
+
+	cpumask_t cpumask;
+	struct file *backing;
+	struct kref refcount;
+	struct list_head va_pages;
+	unsigned long mm_list_version;
+	struct list_head mm_list;
+	spinlock_t mm_lock;
+	struct srcu_struct srcu;
+};
+
+#define SGX_VA_SLOT_COUNT 512
+
+struct sgx_va_page {
+	struct sgx_epc_page *epc_page;
+	DECLARE_BITMAP(slots, SGX_VA_SLOT_COUNT);
+	struct list_head list;
+};
+
+struct sgx_backing {
+	struct page *contents;
+	struct page *pcmd;
+	unsigned long pcmd_offset;
+};
+
+extern const struct vm_operations_struct sgx_vm_ops;
+
+static inline int sgx_encl_find(struct mm_struct *mm, unsigned long addr,
+				struct vm_area_struct **vma)
+{
+	struct vm_area_struct *result;
+
+	result = vma_lookup(mm, addr);
+	if (!result || result->vm_ops != &sgx_vm_ops)
+		return -EINVAL;
+
+	*vma = result;
+
+	return 0;
+}
+
+int sgx_encl_may_map(struct sgx_encl *encl, unsigned long start,
+		     unsigned long end, unsigned long vm_flags);
+
+bool current_is_ksgxd(void);
+void sgx_encl_release(struct kref *ref);
+int sgx_encl_mm_add(struct sgx_encl *encl, struct mm_struct *mm);
+const cpumask_t *sgx_encl_cpumask(struct sgx_encl *encl);
+int sgx_encl_alloc_backing(struct sgx_encl *encl, unsigned long page_index,
+			   struct sgx_backing *backing);
+void sgx_encl_put_backing(struct sgx_backing *backing);
+int sgx_encl_test_and_clear_young(struct mm_struct *mm,
+				  struct sgx_encl_page *page);
+struct sgx_encl_page *sgx_encl_page_alloc(struct sgx_encl *encl,
+					  unsigned long offset,
+					  u64 secinfo_flags);
+void sgx_zap_enclave_ptes(struct sgx_encl *encl, unsigned long addr);
+struct sgx_epc_page *sgx_alloc_va_page(bool reclaim);
+unsigned int sgx_alloc_va_slot(struct sgx_va_page *va_page);
+void sgx_free_va_slot(struct sgx_va_page *va_page, unsigned int offset);
+bool sgx_va_page_full(struct sgx_va_page *va_page);
+void sgx_encl_free_epc_page(struct sgx_epc_page *page);
+struct sgx_encl_page *sgx_encl_load_page(struct sgx_encl *encl,
+					 unsigned long addr);
+struct sgx_va_page *sgx_encl_grow(struct sgx_encl *encl, bool reclaim);
+void sgx_encl_shrink(struct sgx_encl *encl, struct sgx_va_page *va_page);
+
+#endif /* _X86_ENCL_H */
diff --git a/arch/x86/kernel/cpu/sgx/encls.h b/arch/x86/kernel/cpu/sgx/encls.h
new file mode 100644
index 0000000000..99004b02e2
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/encls.h
@@ -0,0 +1,236 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _X86_ENCLS_H
+#define _X86_ENCLS_H
+
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/rwsem.h>
+#include <linux/types.h>
+#include <asm/asm.h>
+#include <asm/traps.h>
+#include "sgx.h"
+
+/* Retrieve the encoded trapnr from the specified return code. */
+#define ENCLS_TRAPNR(r) ((r) & ~SGX_ENCLS_FAULT_FLAG)
+
+/* Issue a WARN() about an ENCLS function. */
+#define ENCLS_WARN(r, name) {						  \
+	do {								  \
+		int _r = (r);						  \
+		WARN_ONCE(_r, "%s returned %d (0x%x)\n", (name), _r, _r); \
+	} while (0);							  \
+}
+
+/*
+ * encls_faulted() - Check if an ENCLS leaf faulted given an error code
+ * @ret:	the return value of an ENCLS leaf function call
+ *
+ * Return:
+ * - true:	ENCLS leaf faulted.
+ * - false:	Otherwise.
+ */
+static inline bool encls_faulted(int ret)
+{
+	return ret & SGX_ENCLS_FAULT_FLAG;
+}
+
+/**
+ * encls_failed() - Check if an ENCLS function failed
+ * @ret:	the return value of an ENCLS function call
+ *
+ * Check if an ENCLS function failed. This happens when the function causes a
+ * fault that is not caused by an EPCM conflict or when the function returns a
+ * non-zero value.
+ */
+static inline bool encls_failed(int ret)
+{
+	if (encls_faulted(ret))
+		return ENCLS_TRAPNR(ret) != X86_TRAP_PF;
+
+	return !!ret;
+}
+
+/**
+ * __encls_ret_N - encode an ENCLS function that returns an error code in EAX
+ * @rax:	function number
+ * @inputs:	asm inputs for the function
+ *
+ * Emit assembly for an ENCLS function that returns an error code, e.g. EREMOVE.
+ * And because SGX isn't complex enough as it is, function that return an error
+ * code also modify flags.
+ *
+ * Return:
+ *	0 on success,
+ *	SGX error code on failure
+ */
+#define __encls_ret_N(rax, inputs...)				\
+	({							\
+	int ret;						\
+	asm volatile(						\
+	"1: .byte 0x0f, 0x01, 0xcf;\n\t"			\
+	"2:\n"							\
+	_ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_FAULT_SGX)		\
+	: "=a"(ret)						\
+	: "a"(rax), inputs					\
+	: "memory", "cc");					\
+	ret;							\
+	})
+
+#define __encls_ret_1(rax, rcx)		\
+	({				\
+	__encls_ret_N(rax, "c"(rcx));	\
+	})
+
+#define __encls_ret_2(rax, rbx, rcx)		\
+	({					\
+	__encls_ret_N(rax, "b"(rbx), "c"(rcx));	\
+	})
+
+#define __encls_ret_3(rax, rbx, rcx, rdx)			\
+	({							\
+	__encls_ret_N(rax, "b"(rbx), "c"(rcx), "d"(rdx));	\
+	})
+
+/**
+ * __encls_N - encode an ENCLS function that doesn't return an error code
+ * @rax:	function number
+ * @rbx_out:	optional output variable
+ * @inputs:	asm inputs for the function
+ *
+ * Emit assembly for an ENCLS function that does not return an error code, e.g.
+ * ECREATE.  Leaves without error codes either succeed or fault.  @rbx_out is an
+ * optional parameter for use by EDGBRD, which returns the requested value in
+ * RBX.
+ *
+ * Return:
+ *   0 on success,
+ *   trapnr with SGX_ENCLS_FAULT_FLAG set on fault
+ */
+#define __encls_N(rax, rbx_out, inputs...)			\
+	({							\
+	int ret;						\
+	asm volatile(						\
+	"1: .byte 0x0f, 0x01, 0xcf;\n\t"			\
+	"   xor %%eax,%%eax;\n"					\
+	"2:\n"							\
+	_ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_FAULT_SGX)		\
+	: "=a"(ret), "=b"(rbx_out)				\
+	: "a"(rax), inputs					\
+	: "memory");						\
+	ret;							\
+	})
+
+#define __encls_2(rax, rbx, rcx)				\
+	({							\
+	unsigned long ign_rbx_out;				\
+	__encls_N(rax, ign_rbx_out, "b"(rbx), "c"(rcx));	\
+	})
+
+#define __encls_1_1(rax, data, rcx)			\
+	({						\
+	unsigned long rbx_out;				\
+	int ret = __encls_N(rax, rbx_out, "c"(rcx));	\
+	if (!ret)					\
+		data = rbx_out;				\
+	ret;						\
+	})
+
+/* Initialize an EPC page into an SGX Enclave Control Structure (SECS) page. */
+static inline int __ecreate(struct sgx_pageinfo *pginfo, void *secs)
+{
+	return __encls_2(ECREATE, pginfo, secs);
+}
+
+/* Hash a 256 byte region of an enclave page to SECS:MRENCLAVE. */
+static inline int __eextend(void *secs, void *addr)
+{
+	return __encls_2(EEXTEND, secs, addr);
+}
+
+/*
+ * Associate an EPC page to an enclave either as a REG or TCS page
+ * populated with the provided data.
+ */
+static inline int __eadd(struct sgx_pageinfo *pginfo, void *addr)
+{
+	return __encls_2(EADD, pginfo, addr);
+}
+
+/* Finalize enclave build, initialize enclave for user code execution. */
+static inline int __einit(void *sigstruct, void *token, void *secs)
+{
+	return __encls_ret_3(EINIT, sigstruct, secs, token);
+}
+
+/* Disassociate EPC page from its enclave and mark it as unused. */
+static inline int __eremove(void *addr)
+{
+	return __encls_ret_1(EREMOVE, addr);
+}
+
+/* Copy data to an EPC page belonging to a debug enclave. */
+static inline int __edbgwr(void *addr, unsigned long *data)
+{
+	return __encls_2(EDGBWR, *data, addr);
+}
+
+/* Copy data from an EPC page belonging to a debug enclave. */
+static inline int __edbgrd(void *addr, unsigned long *data)
+{
+	return __encls_1_1(EDGBRD, *data, addr);
+}
+
+/* Track that software has completed the required TLB address clears. */
+static inline int __etrack(void *addr)
+{
+	return __encls_ret_1(ETRACK, addr);
+}
+
+/* Load, verify, and unblock an EPC page. */
+static inline int __eldu(struct sgx_pageinfo *pginfo, void *addr,
+			 void *va)
+{
+	return __encls_ret_3(ELDU, pginfo, addr, va);
+}
+
+/* Make EPC page inaccessible to enclave, ready to be written to memory. */
+static inline int __eblock(void *addr)
+{
+	return __encls_ret_1(EBLOCK, addr);
+}
+
+/* Initialize an EPC page into a Version Array (VA) page. */
+static inline int __epa(void *addr)
+{
+	unsigned long rbx = SGX_PAGE_TYPE_VA;
+
+	return __encls_2(EPA, rbx, addr);
+}
+
+/* Invalidate an EPC page and write it out to main memory. */
+static inline int __ewb(struct sgx_pageinfo *pginfo, void *addr,
+			void *va)
+{
+	return __encls_ret_3(EWB, pginfo, addr, va);
+}
+
+/* Restrict the EPCM permissions of an EPC page. */
+static inline int __emodpr(struct sgx_secinfo *secinfo, void *addr)
+{
+	return __encls_ret_2(EMODPR, secinfo, addr);
+}
+
+/* Change the type of an EPC page. */
+static inline int __emodt(struct sgx_secinfo *secinfo, void *addr)
+{
+	return __encls_ret_2(EMODT, secinfo, addr);
+}
+
+/* Zero a page of EPC memory and add it to an initialized enclave. */
+static inline int __eaug(struct sgx_pageinfo *pginfo, void *addr)
+{
+	return __encls_2(EAUG, pginfo, addr);
+}
+
+#endif /* _X86_ENCLS_H */
diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c
new file mode 100644
index 0000000000..5d390df214
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/ioctl.c
@@ -0,0 +1,1263 @@
+// SPDX-License-Identifier: GPL-2.0
+/*  Copyright(c) 2016-20 Intel Corporation. */
+
+#include <asm/mman.h>
+#include <asm/sgx.h>
+#include <linux/mman.h>
+#include <linux/delay.h>
+#include <linux/file.h>
+#include <linux/hashtable.h>
+#include <linux/highmem.h>
+#include <linux/ratelimit.h>
+#include <linux/sched/signal.h>
+#include <linux/shmem_fs.h>
+#include <linux/slab.h>
+#include <linux/suspend.h>
+#include "driver.h"
+#include "encl.h"
+#include "encls.h"
+
+struct sgx_va_page *sgx_encl_grow(struct sgx_encl *encl, bool reclaim)
+{
+	struct sgx_va_page *va_page = NULL;
+	void *err;
+
+	BUILD_BUG_ON(SGX_VA_SLOT_COUNT !=
+		(SGX_ENCL_PAGE_VA_OFFSET_MASK >> 3) + 1);
+
+	if (!(encl->page_cnt % SGX_VA_SLOT_COUNT)) {
+		va_page = kzalloc(sizeof(*va_page), GFP_KERNEL);
+		if (!va_page)
+			return ERR_PTR(-ENOMEM);
+
+		va_page->epc_page = sgx_alloc_va_page(reclaim);
+		if (IS_ERR(va_page->epc_page)) {
+			err = ERR_CAST(va_page->epc_page);
+			kfree(va_page);
+			return err;
+		}
+
+		WARN_ON_ONCE(encl->page_cnt % SGX_VA_SLOT_COUNT);
+	}
+	encl->page_cnt++;
+	return va_page;
+}
+
+void sgx_encl_shrink(struct sgx_encl *encl, struct sgx_va_page *va_page)
+{
+	encl->page_cnt--;
+
+	if (va_page) {
+		sgx_encl_free_epc_page(va_page->epc_page);
+		list_del(&va_page->list);
+		kfree(va_page);
+	}
+}
+
+static int sgx_encl_create(struct sgx_encl *encl, struct sgx_secs *secs)
+{
+	struct sgx_epc_page *secs_epc;
+	struct sgx_va_page *va_page;
+	struct sgx_pageinfo pginfo;
+	struct sgx_secinfo secinfo;
+	unsigned long encl_size;
+	struct file *backing;
+	long ret;
+
+	va_page = sgx_encl_grow(encl, true);
+	if (IS_ERR(va_page))
+		return PTR_ERR(va_page);
+	else if (va_page)
+		list_add(&va_page->list, &encl->va_pages);
+	/* else the tail page of the VA page list had free slots. */
+
+	/* The extra page goes to SECS. */
+	encl_size = secs->size + PAGE_SIZE;
+
+	backing = shmem_file_setup("SGX backing", encl_size + (encl_size >> 5),
+				   VM_NORESERVE);
+	if (IS_ERR(backing)) {
+		ret = PTR_ERR(backing);
+		goto err_out_shrink;
+	}
+
+	encl->backing = backing;
+
+	secs_epc = sgx_alloc_epc_page(&encl->secs, true);
+	if (IS_ERR(secs_epc)) {
+		ret = PTR_ERR(secs_epc);
+		goto err_out_backing;
+	}
+
+	encl->secs.epc_page = secs_epc;
+
+	pginfo.addr = 0;
+	pginfo.contents = (unsigned long)secs;
+	pginfo.metadata = (unsigned long)&secinfo;
+	pginfo.secs = 0;
+	memset(&secinfo, 0, sizeof(secinfo));
+
+	ret = __ecreate((void *)&pginfo, sgx_get_epc_virt_addr(secs_epc));
+	if (ret) {
+		ret = -EIO;
+		goto err_out;
+	}
+
+	if (secs->attributes & SGX_ATTR_DEBUG)
+		set_bit(SGX_ENCL_DEBUG, &encl->flags);
+
+	encl->secs.encl = encl;
+	encl->secs.type = SGX_PAGE_TYPE_SECS;
+	encl->base = secs->base;
+	encl->size = secs->size;
+	encl->attributes = secs->attributes;
+	encl->attributes_mask = SGX_ATTR_UNPRIV_MASK;
+
+	/* Set only after completion, as encl->lock has not been taken. */
+	set_bit(SGX_ENCL_CREATED, &encl->flags);
+
+	return 0;
+
+err_out:
+	sgx_encl_free_epc_page(encl->secs.epc_page);
+	encl->secs.epc_page = NULL;
+
+err_out_backing:
+	fput(encl->backing);
+	encl->backing = NULL;
+
+err_out_shrink:
+	sgx_encl_shrink(encl, va_page);
+
+	return ret;
+}
+
+/**
+ * sgx_ioc_enclave_create() - handler for %SGX_IOC_ENCLAVE_CREATE
+ * @encl:	An enclave pointer.
+ * @arg:	The ioctl argument.
+ *
+ * Allocate kernel data structures for the enclave and invoke ECREATE.
+ *
+ * Return:
+ * - 0:		Success.
+ * - -EIO:	ECREATE failed.
+ * - -errno:	POSIX error.
+ */
+static long sgx_ioc_enclave_create(struct sgx_encl *encl, void __user *arg)
+{
+	struct sgx_enclave_create create_arg;
+	void *secs;
+	int ret;
+
+	if (test_bit(SGX_ENCL_CREATED, &encl->flags))
+		return -EINVAL;
+
+	if (copy_from_user(&create_arg, arg, sizeof(create_arg)))
+		return -EFAULT;
+
+	secs = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!secs)
+		return -ENOMEM;
+
+	if (copy_from_user(secs, (void __user *)create_arg.src, PAGE_SIZE))
+		ret = -EFAULT;
+	else
+		ret = sgx_encl_create(encl, secs);
+
+	kfree(secs);
+	return ret;
+}
+
+static int sgx_validate_secinfo(struct sgx_secinfo *secinfo)
+{
+	u64 perm = secinfo->flags & SGX_SECINFO_PERMISSION_MASK;
+	u64 pt   = secinfo->flags & SGX_SECINFO_PAGE_TYPE_MASK;
+
+	if (pt != SGX_SECINFO_REG && pt != SGX_SECINFO_TCS)
+		return -EINVAL;
+
+	if ((perm & SGX_SECINFO_W) && !(perm & SGX_SECINFO_R))
+		return -EINVAL;
+
+	/*
+	 * CPU will silently overwrite the permissions as zero, which means
+	 * that we need to validate it ourselves.
+	 */
+	if (pt == SGX_SECINFO_TCS && perm)
+		return -EINVAL;
+
+	if (secinfo->flags & SGX_SECINFO_RESERVED_MASK)
+		return -EINVAL;
+
+	if (memchr_inv(secinfo->reserved, 0, sizeof(secinfo->reserved)))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int __sgx_encl_add_page(struct sgx_encl *encl,
+			       struct sgx_encl_page *encl_page,
+			       struct sgx_epc_page *epc_page,
+			       struct sgx_secinfo *secinfo, unsigned long src)
+{
+	struct sgx_pageinfo pginfo;
+	struct vm_area_struct *vma;
+	struct page *src_page;
+	int ret;
+
+	/* Deny noexec. */
+	vma = find_vma(current->mm, src);
+	if (!vma)
+		return -EFAULT;
+
+	if (!(vma->vm_flags & VM_MAYEXEC))
+		return -EACCES;
+
+	ret = get_user_pages(src, 1, 0, &src_page);
+	if (ret < 1)
+		return -EFAULT;
+
+	pginfo.secs = (unsigned long)sgx_get_epc_virt_addr(encl->secs.epc_page);
+	pginfo.addr = encl_page->desc & PAGE_MASK;
+	pginfo.metadata = (unsigned long)secinfo;
+	pginfo.contents = (unsigned long)kmap_local_page(src_page);
+
+	ret = __eadd(&pginfo, sgx_get_epc_virt_addr(epc_page));
+
+	kunmap_local((void *)pginfo.contents);
+	put_page(src_page);
+
+	return ret ? -EIO : 0;
+}
+
+/*
+ * If the caller requires measurement of the page as a proof for the content,
+ * use EEXTEND to add a measurement for 256 bytes of the page. Repeat this
+ * operation until the entire page is measured."
+ */
+static int __sgx_encl_extend(struct sgx_encl *encl,
+			     struct sgx_epc_page *epc_page)
+{
+	unsigned long offset;
+	int ret;
+
+	for (offset = 0; offset < PAGE_SIZE; offset += SGX_EEXTEND_BLOCK_SIZE) {
+		ret = __eextend(sgx_get_epc_virt_addr(encl->secs.epc_page),
+				sgx_get_epc_virt_addr(epc_page) + offset);
+		if (ret) {
+			if (encls_failed(ret))
+				ENCLS_WARN(ret, "EEXTEND");
+
+			return -EIO;
+		}
+	}
+
+	return 0;
+}
+
+static int sgx_encl_add_page(struct sgx_encl *encl, unsigned long src,
+			     unsigned long offset, struct sgx_secinfo *secinfo,
+			     unsigned long flags)
+{
+	struct sgx_encl_page *encl_page;
+	struct sgx_epc_page *epc_page;
+	struct sgx_va_page *va_page;
+	int ret;
+
+	encl_page = sgx_encl_page_alloc(encl, offset, secinfo->flags);
+	if (IS_ERR(encl_page))
+		return PTR_ERR(encl_page);
+
+	epc_page = sgx_alloc_epc_page(encl_page, true);
+	if (IS_ERR(epc_page)) {
+		kfree(encl_page);
+		return PTR_ERR(epc_page);
+	}
+
+	va_page = sgx_encl_grow(encl, true);
+	if (IS_ERR(va_page)) {
+		ret = PTR_ERR(va_page);
+		goto err_out_free;
+	}
+
+	mmap_read_lock(current->mm);
+	mutex_lock(&encl->lock);
+
+	/*
+	 * Adding to encl->va_pages must be done under encl->lock.  Ditto for
+	 * deleting (via sgx_encl_shrink()) in the error path.
+	 */
+	if (va_page)
+		list_add(&va_page->list, &encl->va_pages);
+
+	/*
+	 * Insert prior to EADD in case of OOM.  EADD modifies MRENCLAVE, i.e.
+	 * can't be gracefully unwound, while failure on EADD/EXTEND is limited
+	 * to userspace errors (or kernel/hardware bugs).
+	 */
+	ret = xa_insert(&encl->page_array, PFN_DOWN(encl_page->desc),
+			encl_page, GFP_KERNEL);
+	if (ret)
+		goto err_out_unlock;
+
+	ret = __sgx_encl_add_page(encl, encl_page, epc_page, secinfo,
+				  src);
+	if (ret)
+		goto err_out;
+
+	/*
+	 * Complete the "add" before doing the "extend" so that the "add"
+	 * isn't in a half-baked state in the extremely unlikely scenario
+	 * the enclave will be destroyed in response to EEXTEND failure.
+	 */
+	encl_page->encl = encl;
+	encl_page->epc_page = epc_page;
+	encl_page->type = (secinfo->flags & SGX_SECINFO_PAGE_TYPE_MASK) >> 8;
+	encl->secs_child_cnt++;
+
+	if (flags & SGX_PAGE_MEASURE) {
+		ret = __sgx_encl_extend(encl, epc_page);
+		if (ret)
+			goto err_out;
+	}
+
+	sgx_mark_page_reclaimable(encl_page->epc_page);
+	mutex_unlock(&encl->lock);
+	mmap_read_unlock(current->mm);
+	return ret;
+
+err_out:
+	xa_erase(&encl->page_array, PFN_DOWN(encl_page->desc));
+
+err_out_unlock:
+	sgx_encl_shrink(encl, va_page);
+	mutex_unlock(&encl->lock);
+	mmap_read_unlock(current->mm);
+
+err_out_free:
+	sgx_encl_free_epc_page(epc_page);
+	kfree(encl_page);
+
+	return ret;
+}
+
+/*
+ * Ensure user provided offset and length values are valid for
+ * an enclave.
+ */
+static int sgx_validate_offset_length(struct sgx_encl *encl,
+				      unsigned long offset,
+				      unsigned long length)
+{
+	if (!IS_ALIGNED(offset, PAGE_SIZE))
+		return -EINVAL;
+
+	if (!length || !IS_ALIGNED(length, PAGE_SIZE))
+		return -EINVAL;
+
+	if (offset + length < offset)
+		return -EINVAL;
+
+	if (offset + length - PAGE_SIZE >= encl->size)
+		return -EINVAL;
+
+	return 0;
+}
+
+/**
+ * sgx_ioc_enclave_add_pages() - The handler for %SGX_IOC_ENCLAVE_ADD_PAGES
+ * @encl:       an enclave pointer
+ * @arg:	a user pointer to a struct sgx_enclave_add_pages instance
+ *
+ * Add one or more pages to an uninitialized enclave, and optionally extend the
+ * measurement with the contents of the page. The SECINFO and measurement mask
+ * are applied to all pages.
+ *
+ * A SECINFO for a TCS is required to always contain zero permissions because
+ * CPU silently zeros them. Allowing anything else would cause a mismatch in
+ * the measurement.
+ *
+ * mmap()'s protection bits are capped by the page permissions. For each page
+ * address, the maximum protection bits are computed with the following
+ * heuristics:
+ *
+ * 1. A regular page: PROT_R, PROT_W and PROT_X match the SECINFO permissions.
+ * 2. A TCS page: PROT_R | PROT_W.
+ *
+ * mmap() is not allowed to surpass the minimum of the maximum protection bits
+ * within the given address range.
+ *
+ * The function deinitializes kernel data structures for enclave and returns
+ * -EIO in any of the following conditions:
+ *
+ * - Enclave Page Cache (EPC), the physical memory holding enclaves, has
+ *   been invalidated. This will cause EADD and EEXTEND to fail.
+ * - If the source address is corrupted somehow when executing EADD.
+ *
+ * Return:
+ * - 0:		Success.
+ * - -EACCES:	The source page is located in a noexec partition.
+ * - -ENOMEM:	Out of EPC pages.
+ * - -EINTR:	The call was interrupted before data was processed.
+ * - -EIO:	Either EADD or EEXTEND failed because invalid source address
+ *		or power cycle.
+ * - -errno:	POSIX error.
+ */
+static long sgx_ioc_enclave_add_pages(struct sgx_encl *encl, void __user *arg)
+{
+	struct sgx_enclave_add_pages add_arg;
+	struct sgx_secinfo secinfo;
+	unsigned long c;
+	int ret;
+
+	if (!test_bit(SGX_ENCL_CREATED, &encl->flags) ||
+	    test_bit(SGX_ENCL_INITIALIZED, &encl->flags))
+		return -EINVAL;
+
+	if (copy_from_user(&add_arg, arg, sizeof(add_arg)))
+		return -EFAULT;
+
+	if (!IS_ALIGNED(add_arg.src, PAGE_SIZE))
+		return -EINVAL;
+
+	if (sgx_validate_offset_length(encl, add_arg.offset, add_arg.length))
+		return -EINVAL;
+
+	if (copy_from_user(&secinfo, (void __user *)add_arg.secinfo,
+			   sizeof(secinfo)))
+		return -EFAULT;
+
+	if (sgx_validate_secinfo(&secinfo))
+		return -EINVAL;
+
+	for (c = 0 ; c < add_arg.length; c += PAGE_SIZE) {
+		if (signal_pending(current)) {
+			if (!c)
+				ret = -ERESTARTSYS;
+
+			break;
+		}
+
+		if (need_resched())
+			cond_resched();
+
+		ret = sgx_encl_add_page(encl, add_arg.src + c, add_arg.offset + c,
+					&secinfo, add_arg.flags);
+		if (ret)
+			break;
+	}
+
+	add_arg.count = c;
+
+	if (copy_to_user(arg, &add_arg, sizeof(add_arg)))
+		return -EFAULT;
+
+	return ret;
+}
+
+static int __sgx_get_key_hash(struct crypto_shash *tfm, const void *modulus,
+			      void *hash)
+{
+	SHASH_DESC_ON_STACK(shash, tfm);
+
+	shash->tfm = tfm;
+
+	return crypto_shash_digest(shash, modulus, SGX_MODULUS_SIZE, hash);
+}
+
+static int sgx_get_key_hash(const void *modulus, void *hash)
+{
+	struct crypto_shash *tfm;
+	int ret;
+
+	tfm = crypto_alloc_shash("sha256", 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(tfm))
+		return PTR_ERR(tfm);
+
+	ret = __sgx_get_key_hash(tfm, modulus, hash);
+
+	crypto_free_shash(tfm);
+	return ret;
+}
+
+static int sgx_encl_init(struct sgx_encl *encl, struct sgx_sigstruct *sigstruct,
+			 void *token)
+{
+	u64 mrsigner[4];
+	int i, j;
+	void *addr;
+	int ret;
+
+	/*
+	 * Deny initializing enclaves with attributes (namely provisioning)
+	 * that have not been explicitly allowed.
+	 */
+	if (encl->attributes & ~encl->attributes_mask)
+		return -EACCES;
+
+	/*
+	 * Attributes should not be enforced *only* against what's available on
+	 * platform (done in sgx_encl_create) but checked and enforced against
+	 * the mask for enforcement in sigstruct. For example an enclave could
+	 * opt to sign with AVX bit in xfrm, but still be loadable on a platform
+	 * without it if the sigstruct->body.attributes_mask does not turn that
+	 * bit on.
+	 */
+	if (sigstruct->body.attributes & sigstruct->body.attributes_mask &
+	    sgx_attributes_reserved_mask)
+		return -EINVAL;
+
+	if (sigstruct->body.miscselect & sigstruct->body.misc_mask &
+	    sgx_misc_reserved_mask)
+		return -EINVAL;
+
+	if (sigstruct->body.xfrm & sigstruct->body.xfrm_mask &
+	    sgx_xfrm_reserved_mask)
+		return -EINVAL;
+
+	ret = sgx_get_key_hash(sigstruct->modulus, mrsigner);
+	if (ret)
+		return ret;
+
+	mutex_lock(&encl->lock);
+
+	/*
+	 * ENCLS[EINIT] is interruptible because it has such a high latency,
+	 * e.g. 50k+ cycles on success. If an IRQ/NMI/SMI becomes pending,
+	 * EINIT may fail with SGX_UNMASKED_EVENT so that the event can be
+	 * serviced.
+	 */
+	for (i = 0; i < SGX_EINIT_SLEEP_COUNT; i++) {
+		for (j = 0; j < SGX_EINIT_SPIN_COUNT; j++) {
+			addr = sgx_get_epc_virt_addr(encl->secs.epc_page);
+
+			preempt_disable();
+
+			sgx_update_lepubkeyhash(mrsigner);
+
+			ret = __einit(sigstruct, token, addr);
+
+			preempt_enable();
+
+			if (ret == SGX_UNMASKED_EVENT)
+				continue;
+			else
+				break;
+		}
+
+		if (ret != SGX_UNMASKED_EVENT)
+			break;
+
+		msleep_interruptible(SGX_EINIT_SLEEP_TIME);
+
+		if (signal_pending(current)) {
+			ret = -ERESTARTSYS;
+			goto err_out;
+		}
+	}
+
+	if (encls_faulted(ret)) {
+		if (encls_failed(ret))
+			ENCLS_WARN(ret, "EINIT");
+
+		ret = -EIO;
+	} else if (ret) {
+		pr_debug("EINIT returned %d\n", ret);
+		ret = -EPERM;
+	} else {
+		set_bit(SGX_ENCL_INITIALIZED, &encl->flags);
+	}
+
+err_out:
+	mutex_unlock(&encl->lock);
+	return ret;
+}
+
+/**
+ * sgx_ioc_enclave_init() - handler for %SGX_IOC_ENCLAVE_INIT
+ * @encl:	an enclave pointer
+ * @arg:	userspace pointer to a struct sgx_enclave_init instance
+ *
+ * Flush any outstanding enqueued EADD operations and perform EINIT.  The
+ * Launch Enclave Public Key Hash MSRs are rewritten as necessary to match
+ * the enclave's MRSIGNER, which is caculated from the provided sigstruct.
+ *
+ * Return:
+ * - 0:		Success.
+ * - -EPERM:	Invalid SIGSTRUCT.
+ * - -EIO:	EINIT failed because of a power cycle.
+ * - -errno:	POSIX error.
+ */
+static long sgx_ioc_enclave_init(struct sgx_encl *encl, void __user *arg)
+{
+	struct sgx_sigstruct *sigstruct;
+	struct sgx_enclave_init init_arg;
+	void *token;
+	int ret;
+
+	if (!test_bit(SGX_ENCL_CREATED, &encl->flags) ||
+	    test_bit(SGX_ENCL_INITIALIZED, &encl->flags))
+		return -EINVAL;
+
+	if (copy_from_user(&init_arg, arg, sizeof(init_arg)))
+		return -EFAULT;
+
+	/*
+	 * 'sigstruct' must be on a page boundary and 'token' on a 512 byte
+	 * boundary.  kmalloc() will give this alignment when allocating
+	 * PAGE_SIZE bytes.
+	 */
+	sigstruct = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!sigstruct)
+		return -ENOMEM;
+
+	token = (void *)((unsigned long)sigstruct + PAGE_SIZE / 2);
+	memset(token, 0, SGX_LAUNCH_TOKEN_SIZE);
+
+	if (copy_from_user(sigstruct, (void __user *)init_arg.sigstruct,
+			   sizeof(*sigstruct))) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	/*
+	 * A legacy field used with Intel signed enclaves. These used to mean
+	 * regular and architectural enclaves. The CPU only accepts these values
+	 * but they do not have any other meaning.
+	 *
+	 * Thus, reject any other values.
+	 */
+	if (sigstruct->header.vendor != 0x0000 &&
+	    sigstruct->header.vendor != 0x8086) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = sgx_encl_init(encl, sigstruct, token);
+
+out:
+	kfree(sigstruct);
+	return ret;
+}
+
+/**
+ * sgx_ioc_enclave_provision() - handler for %SGX_IOC_ENCLAVE_PROVISION
+ * @encl:	an enclave pointer
+ * @arg:	userspace pointer to a struct sgx_enclave_provision instance
+ *
+ * Allow ATTRIBUTE.PROVISION_KEY for an enclave by providing a file handle to
+ * /dev/sgx_provision.
+ *
+ * Return:
+ * - 0:		Success.
+ * - -errno:	Otherwise.
+ */
+static long sgx_ioc_enclave_provision(struct sgx_encl *encl, void __user *arg)
+{
+	struct sgx_enclave_provision params;
+
+	if (copy_from_user(&params, arg, sizeof(params)))
+		return -EFAULT;
+
+	return sgx_set_attribute(&encl->attributes_mask, params.fd);
+}
+
+/*
+ * Ensure enclave is ready for SGX2 functions. Readiness is checked
+ * by ensuring the hardware supports SGX2 and the enclave is initialized
+ * and thus able to handle requests to modify pages within it.
+ */
+static int sgx_ioc_sgx2_ready(struct sgx_encl *encl)
+{
+	if (!(cpu_feature_enabled(X86_FEATURE_SGX2)))
+		return -ENODEV;
+
+	if (!test_bit(SGX_ENCL_INITIALIZED, &encl->flags))
+		return -EINVAL;
+
+	return 0;
+}
+
+/*
+ * Some SGX functions require that no cached linear-to-physical address
+ * mappings are present before they can succeed. Collaborate with
+ * hardware via ENCLS[ETRACK] to ensure that all cached
+ * linear-to-physical address mappings belonging to all threads of
+ * the enclave are cleared. See sgx_encl_cpumask() for details.
+ *
+ * Must be called with enclave's mutex held from the time the
+ * SGX function requiring that no cached linear-to-physical mappings
+ * are present is executed until this ETRACK flow is complete.
+ */
+static int sgx_enclave_etrack(struct sgx_encl *encl)
+{
+	void *epc_virt;
+	int ret;
+
+	epc_virt = sgx_get_epc_virt_addr(encl->secs.epc_page);
+	ret = __etrack(epc_virt);
+	if (ret) {
+		/*
+		 * ETRACK only fails when there is an OS issue. For
+		 * example, two consecutive ETRACK was sent without
+		 * completed IPI between.
+		 */
+		pr_err_once("ETRACK returned %d (0x%x)", ret, ret);
+		/*
+		 * Send IPIs to kick CPUs out of the enclave and
+		 * try ETRACK again.
+		 */
+		on_each_cpu_mask(sgx_encl_cpumask(encl), sgx_ipi_cb, NULL, 1);
+		ret = __etrack(epc_virt);
+		if (ret) {
+			pr_err_once("ETRACK repeat returned %d (0x%x)",
+				    ret, ret);
+			return -EFAULT;
+		}
+	}
+	on_each_cpu_mask(sgx_encl_cpumask(encl), sgx_ipi_cb, NULL, 1);
+
+	return 0;
+}
+
+/**
+ * sgx_enclave_restrict_permissions() - Restrict EPCM permissions
+ * @encl:	Enclave to which the pages belong.
+ * @modp:	Checked parameters from user on which pages need modifying and
+ *              their new permissions.
+ *
+ * Return:
+ * - 0:		Success.
+ * - -errno:	Otherwise.
+ */
+static long
+sgx_enclave_restrict_permissions(struct sgx_encl *encl,
+				 struct sgx_enclave_restrict_permissions *modp)
+{
+	struct sgx_encl_page *entry;
+	struct sgx_secinfo secinfo;
+	unsigned long addr;
+	unsigned long c;
+	void *epc_virt;
+	int ret;
+
+	memset(&secinfo, 0, sizeof(secinfo));
+	secinfo.flags = modp->permissions & SGX_SECINFO_PERMISSION_MASK;
+
+	for (c = 0 ; c < modp->length; c += PAGE_SIZE) {
+		addr = encl->base + modp->offset + c;
+
+		sgx_reclaim_direct();
+
+		mutex_lock(&encl->lock);
+
+		entry = sgx_encl_load_page(encl, addr);
+		if (IS_ERR(entry)) {
+			ret = PTR_ERR(entry) == -EBUSY ? -EAGAIN : -EFAULT;
+			goto out_unlock;
+		}
+
+		/*
+		 * Changing EPCM permissions is only supported on regular
+		 * SGX pages. Attempting this change on other pages will
+		 * result in #PF.
+		 */
+		if (entry->type != SGX_PAGE_TYPE_REG) {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+
+		/*
+		 * Apart from ensuring that read-access remains, do not verify
+		 * the permission bits requested. Kernel has no control over
+		 * how EPCM permissions can be relaxed from within the enclave.
+		 * ENCLS[EMODPR] can only remove existing EPCM permissions,
+		 * attempting to set new permissions will be ignored by the
+		 * hardware.
+		 */
+
+		/* Change EPCM permissions. */
+		epc_virt = sgx_get_epc_virt_addr(entry->epc_page);
+		ret = __emodpr(&secinfo, epc_virt);
+		if (encls_faulted(ret)) {
+			/*
+			 * All possible faults should be avoidable:
+			 * parameters have been checked, will only change
+			 * permissions of a regular page, and no concurrent
+			 * SGX1/SGX2 ENCLS instructions since these
+			 * are protected with mutex.
+			 */
+			pr_err_once("EMODPR encountered exception %d\n",
+				    ENCLS_TRAPNR(ret));
+			ret = -EFAULT;
+			goto out_unlock;
+		}
+		if (encls_failed(ret)) {
+			modp->result = ret;
+			ret = -EFAULT;
+			goto out_unlock;
+		}
+
+		ret = sgx_enclave_etrack(encl);
+		if (ret) {
+			ret = -EFAULT;
+			goto out_unlock;
+		}
+
+		mutex_unlock(&encl->lock);
+	}
+
+	ret = 0;
+	goto out;
+
+out_unlock:
+	mutex_unlock(&encl->lock);
+out:
+	modp->count = c;
+
+	return ret;
+}
+
+/**
+ * sgx_ioc_enclave_restrict_permissions() - handler for
+ *                                        %SGX_IOC_ENCLAVE_RESTRICT_PERMISSIONS
+ * @encl:	an enclave pointer
+ * @arg:	userspace pointer to a &struct sgx_enclave_restrict_permissions
+ *		instance
+ *
+ * SGX2 distinguishes between relaxing and restricting the enclave page
+ * permissions maintained by the hardware (EPCM permissions) of pages
+ * belonging to an initialized enclave (after SGX_IOC_ENCLAVE_INIT).
+ *
+ * EPCM permissions cannot be restricted from within the enclave, the enclave
+ * requires the kernel to run the privileged level 0 instructions ENCLS[EMODPR]
+ * and ENCLS[ETRACK]. An attempt to relax EPCM permissions with this call
+ * will be ignored by the hardware.
+ *
+ * Return:
+ * - 0:		Success
+ * - -errno:	Otherwise
+ */
+static long sgx_ioc_enclave_restrict_permissions(struct sgx_encl *encl,
+						 void __user *arg)
+{
+	struct sgx_enclave_restrict_permissions params;
+	long ret;
+
+	ret = sgx_ioc_sgx2_ready(encl);
+	if (ret)
+		return ret;
+
+	if (copy_from_user(&params, arg, sizeof(params)))
+		return -EFAULT;
+
+	if (sgx_validate_offset_length(encl, params.offset, params.length))
+		return -EINVAL;
+
+	if (params.permissions & ~SGX_SECINFO_PERMISSION_MASK)
+		return -EINVAL;
+
+	/*
+	 * Fail early if invalid permissions requested to prevent ENCLS[EMODPR]
+	 * from faulting later when the CPU does the same check.
+	 */
+	if ((params.permissions & SGX_SECINFO_W) &&
+	    !(params.permissions & SGX_SECINFO_R))
+		return -EINVAL;
+
+	if (params.result || params.count)
+		return -EINVAL;
+
+	ret = sgx_enclave_restrict_permissions(encl, &params);
+
+	if (copy_to_user(arg, &params, sizeof(params)))
+		return -EFAULT;
+
+	return ret;
+}
+
+/**
+ * sgx_enclave_modify_types() - Modify type of SGX enclave pages
+ * @encl:	Enclave to which the pages belong.
+ * @modt:	Checked parameters from user about which pages need modifying
+ *              and their new page type.
+ *
+ * Return:
+ * - 0:		Success
+ * - -errno:	Otherwise
+ */
+static long sgx_enclave_modify_types(struct sgx_encl *encl,
+				     struct sgx_enclave_modify_types *modt)
+{
+	unsigned long max_prot_restore;
+	enum sgx_page_type page_type;
+	struct sgx_encl_page *entry;
+	struct sgx_secinfo secinfo;
+	unsigned long prot;
+	unsigned long addr;
+	unsigned long c;
+	void *epc_virt;
+	int ret;
+
+	page_type = modt->page_type & SGX_PAGE_TYPE_MASK;
+
+	/*
+	 * The only new page types allowed by hardware are PT_TCS and PT_TRIM.
+	 */
+	if (page_type != SGX_PAGE_TYPE_TCS && page_type != SGX_PAGE_TYPE_TRIM)
+		return -EINVAL;
+
+	memset(&secinfo, 0, sizeof(secinfo));
+
+	secinfo.flags = page_type << 8;
+
+	for (c = 0 ; c < modt->length; c += PAGE_SIZE) {
+		addr = encl->base + modt->offset + c;
+
+		sgx_reclaim_direct();
+
+		mutex_lock(&encl->lock);
+
+		entry = sgx_encl_load_page(encl, addr);
+		if (IS_ERR(entry)) {
+			ret = PTR_ERR(entry) == -EBUSY ? -EAGAIN : -EFAULT;
+			goto out_unlock;
+		}
+
+		/*
+		 * Borrow the logic from the Intel SDM. Regular pages
+		 * (SGX_PAGE_TYPE_REG) can change type to SGX_PAGE_TYPE_TCS
+		 * or SGX_PAGE_TYPE_TRIM but TCS pages can only be trimmed.
+		 * CET pages not supported yet.
+		 */
+		if (!(entry->type == SGX_PAGE_TYPE_REG ||
+		      (entry->type == SGX_PAGE_TYPE_TCS &&
+		       page_type == SGX_PAGE_TYPE_TRIM))) {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+
+		max_prot_restore = entry->vm_max_prot_bits;
+
+		/*
+		 * Once a regular page becomes a TCS page it cannot be
+		 * changed back. So the maximum allowed protection reflects
+		 * the TCS page that is always RW from kernel perspective but
+		 * will be inaccessible from within enclave. Before doing
+		 * so, do make sure that the new page type continues to
+		 * respect the originally vetted page permissions.
+		 */
+		if (entry->type == SGX_PAGE_TYPE_REG &&
+		    page_type == SGX_PAGE_TYPE_TCS) {
+			if (~entry->vm_max_prot_bits & (VM_READ | VM_WRITE)) {
+				ret = -EPERM;
+				goto out_unlock;
+			}
+			prot = PROT_READ | PROT_WRITE;
+			entry->vm_max_prot_bits = calc_vm_prot_bits(prot, 0);
+
+			/*
+			 * Prevent page from being reclaimed while mutex
+			 * is released.
+			 */
+			if (sgx_unmark_page_reclaimable(entry->epc_page)) {
+				ret = -EAGAIN;
+				goto out_entry_changed;
+			}
+
+			/*
+			 * Do not keep encl->lock because of dependency on
+			 * mmap_lock acquired in sgx_zap_enclave_ptes().
+			 */
+			mutex_unlock(&encl->lock);
+
+			sgx_zap_enclave_ptes(encl, addr);
+
+			mutex_lock(&encl->lock);
+
+			sgx_mark_page_reclaimable(entry->epc_page);
+		}
+
+		/* Change EPC type */
+		epc_virt = sgx_get_epc_virt_addr(entry->epc_page);
+		ret = __emodt(&secinfo, epc_virt);
+		if (encls_faulted(ret)) {
+			/*
+			 * All possible faults should be avoidable:
+			 * parameters have been checked, will only change
+			 * valid page types, and no concurrent
+			 * SGX1/SGX2 ENCLS instructions since these are
+			 * protected with mutex.
+			 */
+			pr_err_once("EMODT encountered exception %d\n",
+				    ENCLS_TRAPNR(ret));
+			ret = -EFAULT;
+			goto out_entry_changed;
+		}
+		if (encls_failed(ret)) {
+			modt->result = ret;
+			ret = -EFAULT;
+			goto out_entry_changed;
+		}
+
+		ret = sgx_enclave_etrack(encl);
+		if (ret) {
+			ret = -EFAULT;
+			goto out_unlock;
+		}
+
+		entry->type = page_type;
+
+		mutex_unlock(&encl->lock);
+	}
+
+	ret = 0;
+	goto out;
+
+out_entry_changed:
+	entry->vm_max_prot_bits = max_prot_restore;
+out_unlock:
+	mutex_unlock(&encl->lock);
+out:
+	modt->count = c;
+
+	return ret;
+}
+
+/**
+ * sgx_ioc_enclave_modify_types() - handler for %SGX_IOC_ENCLAVE_MODIFY_TYPES
+ * @encl:	an enclave pointer
+ * @arg:	userspace pointer to a &struct sgx_enclave_modify_types instance
+ *
+ * Ability to change the enclave page type supports the following use cases:
+ *
+ * * It is possible to add TCS pages to an enclave by changing the type of
+ *   regular pages (%SGX_PAGE_TYPE_REG) to TCS (%SGX_PAGE_TYPE_TCS) pages.
+ *   With this support the number of threads supported by an initialized
+ *   enclave can be increased dynamically.
+ *
+ * * Regular or TCS pages can dynamically be removed from an initialized
+ *   enclave by changing the page type to %SGX_PAGE_TYPE_TRIM. Changing the
+ *   page type to %SGX_PAGE_TYPE_TRIM marks the page for removal with actual
+ *   removal done by handler of %SGX_IOC_ENCLAVE_REMOVE_PAGES ioctl() called
+ *   after ENCLU[EACCEPT] is run on %SGX_PAGE_TYPE_TRIM page from within the
+ *   enclave.
+ *
+ * Return:
+ * - 0:		Success
+ * - -errno:	Otherwise
+ */
+static long sgx_ioc_enclave_modify_types(struct sgx_encl *encl,
+					 void __user *arg)
+{
+	struct sgx_enclave_modify_types params;
+	long ret;
+
+	ret = sgx_ioc_sgx2_ready(encl);
+	if (ret)
+		return ret;
+
+	if (copy_from_user(&params, arg, sizeof(params)))
+		return -EFAULT;
+
+	if (sgx_validate_offset_length(encl, params.offset, params.length))
+		return -EINVAL;
+
+	if (params.page_type & ~SGX_PAGE_TYPE_MASK)
+		return -EINVAL;
+
+	if (params.result || params.count)
+		return -EINVAL;
+
+	ret = sgx_enclave_modify_types(encl, &params);
+
+	if (copy_to_user(arg, &params, sizeof(params)))
+		return -EFAULT;
+
+	return ret;
+}
+
+/**
+ * sgx_encl_remove_pages() - Remove trimmed pages from SGX enclave
+ * @encl:	Enclave to which the pages belong
+ * @params:	Checked parameters from user on which pages need to be removed
+ *
+ * Return:
+ * - 0:		Success.
+ * - -errno:	Otherwise.
+ */
+static long sgx_encl_remove_pages(struct sgx_encl *encl,
+				  struct sgx_enclave_remove_pages *params)
+{
+	struct sgx_encl_page *entry;
+	struct sgx_secinfo secinfo;
+	unsigned long addr;
+	unsigned long c;
+	void *epc_virt;
+	int ret;
+
+	memset(&secinfo, 0, sizeof(secinfo));
+	secinfo.flags = SGX_SECINFO_R | SGX_SECINFO_W | SGX_SECINFO_X;
+
+	for (c = 0 ; c < params->length; c += PAGE_SIZE) {
+		addr = encl->base + params->offset + c;
+
+		sgx_reclaim_direct();
+
+		mutex_lock(&encl->lock);
+
+		entry = sgx_encl_load_page(encl, addr);
+		if (IS_ERR(entry)) {
+			ret = PTR_ERR(entry) == -EBUSY ? -EAGAIN : -EFAULT;
+			goto out_unlock;
+		}
+
+		if (entry->type != SGX_PAGE_TYPE_TRIM) {
+			ret = -EPERM;
+			goto out_unlock;
+		}
+
+		/*
+		 * ENCLS[EMODPR] is a no-op instruction used to inform if
+		 * ENCLU[EACCEPT] was run from within the enclave. If
+		 * ENCLS[EMODPR] is run with RWX on a trimmed page that is
+		 * not yet accepted then it will return
+		 * %SGX_PAGE_NOT_MODIFIABLE, after the trimmed page is
+		 * accepted the instruction will encounter a page fault.
+		 */
+		epc_virt = sgx_get_epc_virt_addr(entry->epc_page);
+		ret = __emodpr(&secinfo, epc_virt);
+		if (!encls_faulted(ret) || ENCLS_TRAPNR(ret) != X86_TRAP_PF) {
+			ret = -EPERM;
+			goto out_unlock;
+		}
+
+		if (sgx_unmark_page_reclaimable(entry->epc_page)) {
+			ret = -EBUSY;
+			goto out_unlock;
+		}
+
+		/*
+		 * Do not keep encl->lock because of dependency on
+		 * mmap_lock acquired in sgx_zap_enclave_ptes().
+		 */
+		mutex_unlock(&encl->lock);
+
+		sgx_zap_enclave_ptes(encl, addr);
+
+		mutex_lock(&encl->lock);
+
+		sgx_encl_free_epc_page(entry->epc_page);
+		encl->secs_child_cnt--;
+		entry->epc_page = NULL;
+		xa_erase(&encl->page_array, PFN_DOWN(entry->desc));
+		sgx_encl_shrink(encl, NULL);
+		kfree(entry);
+
+		mutex_unlock(&encl->lock);
+	}
+
+	ret = 0;
+	goto out;
+
+out_unlock:
+	mutex_unlock(&encl->lock);
+out:
+	params->count = c;
+
+	return ret;
+}
+
+/**
+ * sgx_ioc_enclave_remove_pages() - handler for %SGX_IOC_ENCLAVE_REMOVE_PAGES
+ * @encl:	an enclave pointer
+ * @arg:	userspace pointer to &struct sgx_enclave_remove_pages instance
+ *
+ * Final step of the flow removing pages from an initialized enclave. The
+ * complete flow is:
+ *
+ * 1) User changes the type of the pages to be removed to %SGX_PAGE_TYPE_TRIM
+ *    using the %SGX_IOC_ENCLAVE_MODIFY_TYPES ioctl().
+ * 2) User approves the page removal by running ENCLU[EACCEPT] from within
+ *    the enclave.
+ * 3) User initiates actual page removal using the
+ *    %SGX_IOC_ENCLAVE_REMOVE_PAGES ioctl() that is handled here.
+ *
+ * First remove any page table entries pointing to the page and then proceed
+ * with the actual removal of the enclave page and data in support of it.
+ *
+ * VA pages are not affected by this removal. It is thus possible that the
+ * enclave may end up with more VA pages than needed to support all its
+ * pages.
+ *
+ * Return:
+ * - 0:		Success
+ * - -errno:	Otherwise
+ */
+static long sgx_ioc_enclave_remove_pages(struct sgx_encl *encl,
+					 void __user *arg)
+{
+	struct sgx_enclave_remove_pages params;
+	long ret;
+
+	ret = sgx_ioc_sgx2_ready(encl);
+	if (ret)
+		return ret;
+
+	if (copy_from_user(&params, arg, sizeof(params)))
+		return -EFAULT;
+
+	if (sgx_validate_offset_length(encl, params.offset, params.length))
+		return -EINVAL;
+
+	if (params.count)
+		return -EINVAL;
+
+	ret = sgx_encl_remove_pages(encl, &params);
+
+	if (copy_to_user(arg, &params, sizeof(params)))
+		return -EFAULT;
+
+	return ret;
+}
+
+long sgx_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
+{
+	struct sgx_encl *encl = filep->private_data;
+	int ret;
+
+	if (test_and_set_bit(SGX_ENCL_IOCTL, &encl->flags))
+		return -EBUSY;
+
+	switch (cmd) {
+	case SGX_IOC_ENCLAVE_CREATE:
+		ret = sgx_ioc_enclave_create(encl, (void __user *)arg);
+		break;
+	case SGX_IOC_ENCLAVE_ADD_PAGES:
+		ret = sgx_ioc_enclave_add_pages(encl, (void __user *)arg);
+		break;
+	case SGX_IOC_ENCLAVE_INIT:
+		ret = sgx_ioc_enclave_init(encl, (void __user *)arg);
+		break;
+	case SGX_IOC_ENCLAVE_PROVISION:
+		ret = sgx_ioc_enclave_provision(encl, (void __user *)arg);
+		break;
+	case SGX_IOC_ENCLAVE_RESTRICT_PERMISSIONS:
+		ret = sgx_ioc_enclave_restrict_permissions(encl,
+							   (void __user *)arg);
+		break;
+	case SGX_IOC_ENCLAVE_MODIFY_TYPES:
+		ret = sgx_ioc_enclave_modify_types(encl, (void __user *)arg);
+		break;
+	case SGX_IOC_ENCLAVE_REMOVE_PAGES:
+		ret = sgx_ioc_enclave_remove_pages(encl, (void __user *)arg);
+		break;
+	default:
+		ret = -ENOIOCTLCMD;
+		break;
+	}
+
+	clear_bit(SGX_ENCL_IOCTL, &encl->flags);
+	return ret;
+}
diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
new file mode 100644
index 0000000000..166692f2d5
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/main.c
@@ -0,0 +1,962 @@
+// SPDX-License-Identifier: GPL-2.0
+/*  Copyright(c) 2016-20 Intel Corporation. */
+
+#include <linux/file.h>
+#include <linux/freezer.h>
+#include <linux/highmem.h>
+#include <linux/kthread.h>
+#include <linux/miscdevice.h>
+#include <linux/node.h>
+#include <linux/pagemap.h>
+#include <linux/ratelimit.h>
+#include <linux/sched/mm.h>
+#include <linux/sched/signal.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <asm/sgx.h>
+#include "driver.h"
+#include "encl.h"
+#include "encls.h"
+
+struct sgx_epc_section sgx_epc_sections[SGX_MAX_EPC_SECTIONS];
+static int sgx_nr_epc_sections;
+static struct task_struct *ksgxd_tsk;
+static DECLARE_WAIT_QUEUE_HEAD(ksgxd_waitq);
+static DEFINE_XARRAY(sgx_epc_address_space);
+
+/*
+ * These variables are part of the state of the reclaimer, and must be accessed
+ * with sgx_reclaimer_lock acquired.
+ */
+static LIST_HEAD(sgx_active_page_list);
+static DEFINE_SPINLOCK(sgx_reclaimer_lock);
+
+static atomic_long_t sgx_nr_free_pages = ATOMIC_LONG_INIT(0);
+
+/* Nodes with one or more EPC sections. */
+static nodemask_t sgx_numa_mask;
+
+/*
+ * Array with one list_head for each possible NUMA node.  Each
+ * list contains all the sgx_epc_section's which are on that
+ * node.
+ */
+static struct sgx_numa_node *sgx_numa_nodes;
+
+static LIST_HEAD(sgx_dirty_page_list);
+
+/*
+ * Reset post-kexec EPC pages to the uninitialized state. The pages are removed
+ * from the input list, and made available for the page allocator. SECS pages
+ * prepending their children in the input list are left intact.
+ *
+ * Return 0 when sanitization was successful or kthread was stopped, and the
+ * number of unsanitized pages otherwise.
+ */
+static unsigned long __sgx_sanitize_pages(struct list_head *dirty_page_list)
+{
+	unsigned long left_dirty = 0;
+	struct sgx_epc_page *page;
+	LIST_HEAD(dirty);
+	int ret;
+
+	/* dirty_page_list is thread-local, no need for a lock: */
+	while (!list_empty(dirty_page_list)) {
+		if (kthread_should_stop())
+			return 0;
+
+		page = list_first_entry(dirty_page_list, struct sgx_epc_page, list);
+
+		/*
+		 * Checking page->poison without holding the node->lock
+		 * is racy, but losing the race (i.e. poison is set just
+		 * after the check) just means __eremove() will be uselessly
+		 * called for a page that sgx_free_epc_page() will put onto
+		 * the node->sgx_poison_page_list later.
+		 */
+		if (page->poison) {
+			struct sgx_epc_section *section = &sgx_epc_sections[page->section];
+			struct sgx_numa_node *node = section->node;
+
+			spin_lock(&node->lock);
+			list_move(&page->list, &node->sgx_poison_page_list);
+			spin_unlock(&node->lock);
+
+			continue;
+		}
+
+		ret = __eremove(sgx_get_epc_virt_addr(page));
+		if (!ret) {
+			/*
+			 * page is now sanitized.  Make it available via the SGX
+			 * page allocator:
+			 */
+			list_del(&page->list);
+			sgx_free_epc_page(page);
+		} else {
+			/* The page is not yet clean - move to the dirty list. */
+			list_move_tail(&page->list, &dirty);
+			left_dirty++;
+		}
+
+		cond_resched();
+	}
+
+	list_splice(&dirty, dirty_page_list);
+	return left_dirty;
+}
+
+static bool sgx_reclaimer_age(struct sgx_epc_page *epc_page)
+{
+	struct sgx_encl_page *page = epc_page->owner;
+	struct sgx_encl *encl = page->encl;
+	struct sgx_encl_mm *encl_mm;
+	bool ret = true;
+	int idx;
+
+	idx = srcu_read_lock(&encl->srcu);
+
+	list_for_each_entry_rcu(encl_mm, &encl->mm_list, list) {
+		if (!mmget_not_zero(encl_mm->mm))
+			continue;
+
+		mmap_read_lock(encl_mm->mm);
+		ret = !sgx_encl_test_and_clear_young(encl_mm->mm, page);
+		mmap_read_unlock(encl_mm->mm);
+
+		mmput_async(encl_mm->mm);
+
+		if (!ret)
+			break;
+	}
+
+	srcu_read_unlock(&encl->srcu, idx);
+
+	if (!ret)
+		return false;
+
+	return true;
+}
+
+static void sgx_reclaimer_block(struct sgx_epc_page *epc_page)
+{
+	struct sgx_encl_page *page = epc_page->owner;
+	unsigned long addr = page->desc & PAGE_MASK;
+	struct sgx_encl *encl = page->encl;
+	int ret;
+
+	sgx_zap_enclave_ptes(encl, addr);
+
+	mutex_lock(&encl->lock);
+
+	ret = __eblock(sgx_get_epc_virt_addr(epc_page));
+	if (encls_failed(ret))
+		ENCLS_WARN(ret, "EBLOCK");
+
+	mutex_unlock(&encl->lock);
+}
+
+static int __sgx_encl_ewb(struct sgx_epc_page *epc_page, void *va_slot,
+			  struct sgx_backing *backing)
+{
+	struct sgx_pageinfo pginfo;
+	int ret;
+
+	pginfo.addr = 0;
+	pginfo.secs = 0;
+
+	pginfo.contents = (unsigned long)kmap_local_page(backing->contents);
+	pginfo.metadata = (unsigned long)kmap_local_page(backing->pcmd) +
+			  backing->pcmd_offset;
+
+	ret = __ewb(&pginfo, sgx_get_epc_virt_addr(epc_page), va_slot);
+	set_page_dirty(backing->pcmd);
+	set_page_dirty(backing->contents);
+
+	kunmap_local((void *)(unsigned long)(pginfo.metadata -
+					      backing->pcmd_offset));
+	kunmap_local((void *)(unsigned long)pginfo.contents);
+
+	return ret;
+}
+
+void sgx_ipi_cb(void *info)
+{
+}
+
+/*
+ * Swap page to the regular memory transformed to the blocked state by using
+ * EBLOCK, which means that it can no longer be referenced (no new TLB entries).
+ *
+ * The first trial just tries to write the page assuming that some other thread
+ * has reset the count for threads inside the enclave by using ETRACK, and
+ * previous thread count has been zeroed out. The second trial calls ETRACK
+ * before EWB. If that fails we kick all the HW threads out, and then do EWB,
+ * which should be guaranteed the succeed.
+ */
+static void sgx_encl_ewb(struct sgx_epc_page *epc_page,
+			 struct sgx_backing *backing)
+{
+	struct sgx_encl_page *encl_page = epc_page->owner;
+	struct sgx_encl *encl = encl_page->encl;
+	struct sgx_va_page *va_page;
+	unsigned int va_offset;
+	void *va_slot;
+	int ret;
+
+	encl_page->desc &= ~SGX_ENCL_PAGE_BEING_RECLAIMED;
+
+	va_page = list_first_entry(&encl->va_pages, struct sgx_va_page,
+				   list);
+	va_offset = sgx_alloc_va_slot(va_page);
+	va_slot = sgx_get_epc_virt_addr(va_page->epc_page) + va_offset;
+	if (sgx_va_page_full(va_page))
+		list_move_tail(&va_page->list, &encl->va_pages);
+
+	ret = __sgx_encl_ewb(epc_page, va_slot, backing);
+	if (ret == SGX_NOT_TRACKED) {
+		ret = __etrack(sgx_get_epc_virt_addr(encl->secs.epc_page));
+		if (ret) {
+			if (encls_failed(ret))
+				ENCLS_WARN(ret, "ETRACK");
+		}
+
+		ret = __sgx_encl_ewb(epc_page, va_slot, backing);
+		if (ret == SGX_NOT_TRACKED) {
+			/*
+			 * Slow path, send IPIs to kick cpus out of the
+			 * enclave.  Note, it's imperative that the cpu
+			 * mask is generated *after* ETRACK, else we'll
+			 * miss cpus that entered the enclave between
+			 * generating the mask and incrementing epoch.
+			 */
+			on_each_cpu_mask(sgx_encl_cpumask(encl),
+					 sgx_ipi_cb, NULL, 1);
+			ret = __sgx_encl_ewb(epc_page, va_slot, backing);
+		}
+	}
+
+	if (ret) {
+		if (encls_failed(ret))
+			ENCLS_WARN(ret, "EWB");
+
+		sgx_free_va_slot(va_page, va_offset);
+	} else {
+		encl_page->desc |= va_offset;
+		encl_page->va_page = va_page;
+	}
+}
+
+static void sgx_reclaimer_write(struct sgx_epc_page *epc_page,
+				struct sgx_backing *backing)
+{
+	struct sgx_encl_page *encl_page = epc_page->owner;
+	struct sgx_encl *encl = encl_page->encl;
+	struct sgx_backing secs_backing;
+	int ret;
+
+	mutex_lock(&encl->lock);
+
+	sgx_encl_ewb(epc_page, backing);
+	encl_page->epc_page = NULL;
+	encl->secs_child_cnt--;
+	sgx_encl_put_backing(backing);
+
+	if (!encl->secs_child_cnt && test_bit(SGX_ENCL_INITIALIZED, &encl->flags)) {
+		ret = sgx_encl_alloc_backing(encl, PFN_DOWN(encl->size),
+					   &secs_backing);
+		if (ret)
+			goto out;
+
+		sgx_encl_ewb(encl->secs.epc_page, &secs_backing);
+
+		sgx_encl_free_epc_page(encl->secs.epc_page);
+		encl->secs.epc_page = NULL;
+
+		sgx_encl_put_backing(&secs_backing);
+	}
+
+out:
+	mutex_unlock(&encl->lock);
+}
+
+/*
+ * Take a fixed number of pages from the head of the active page pool and
+ * reclaim them to the enclave's private shmem files. Skip the pages, which have
+ * been accessed since the last scan. Move those pages to the tail of active
+ * page pool so that the pages get scanned in LRU like fashion.
+ *
+ * Batch process a chunk of pages (at the moment 16) in order to degrade amount
+ * of IPI's and ETRACK's potentially required. sgx_encl_ewb() does degrade a bit
+ * among the HW threads with three stage EWB pipeline (EWB, ETRACK + EWB and IPI
+ * + EWB) but not sufficiently. Reclaiming one page at a time would also be
+ * problematic as it would increase the lock contention too much, which would
+ * halt forward progress.
+ */
+static void sgx_reclaim_pages(void)
+{
+	struct sgx_epc_page *chunk[SGX_NR_TO_SCAN];
+	struct sgx_backing backing[SGX_NR_TO_SCAN];
+	struct sgx_encl_page *encl_page;
+	struct sgx_epc_page *epc_page;
+	pgoff_t page_index;
+	int cnt = 0;
+	int ret;
+	int i;
+
+	spin_lock(&sgx_reclaimer_lock);
+	for (i = 0; i < SGX_NR_TO_SCAN; i++) {
+		if (list_empty(&sgx_active_page_list))
+			break;
+
+		epc_page = list_first_entry(&sgx_active_page_list,
+					    struct sgx_epc_page, list);
+		list_del_init(&epc_page->list);
+		encl_page = epc_page->owner;
+
+		if (kref_get_unless_zero(&encl_page->encl->refcount) != 0)
+			chunk[cnt++] = epc_page;
+		else
+			/* The owner is freeing the page. No need to add the
+			 * page back to the list of reclaimable pages.
+			 */
+			epc_page->flags &= ~SGX_EPC_PAGE_RECLAIMER_TRACKED;
+	}
+	spin_unlock(&sgx_reclaimer_lock);
+
+	for (i = 0; i < cnt; i++) {
+		epc_page = chunk[i];
+		encl_page = epc_page->owner;
+
+		if (!sgx_reclaimer_age(epc_page))
+			goto skip;
+
+		page_index = PFN_DOWN(encl_page->desc - encl_page->encl->base);
+
+		mutex_lock(&encl_page->encl->lock);
+		ret = sgx_encl_alloc_backing(encl_page->encl, page_index, &backing[i]);
+		if (ret) {
+			mutex_unlock(&encl_page->encl->lock);
+			goto skip;
+		}
+
+		encl_page->desc |= SGX_ENCL_PAGE_BEING_RECLAIMED;
+		mutex_unlock(&encl_page->encl->lock);
+		continue;
+
+skip:
+		spin_lock(&sgx_reclaimer_lock);
+		list_add_tail(&epc_page->list, &sgx_active_page_list);
+		spin_unlock(&sgx_reclaimer_lock);
+
+		kref_put(&encl_page->encl->refcount, sgx_encl_release);
+
+		chunk[i] = NULL;
+	}
+
+	for (i = 0; i < cnt; i++) {
+		epc_page = chunk[i];
+		if (epc_page)
+			sgx_reclaimer_block(epc_page);
+	}
+
+	for (i = 0; i < cnt; i++) {
+		epc_page = chunk[i];
+		if (!epc_page)
+			continue;
+
+		encl_page = epc_page->owner;
+		sgx_reclaimer_write(epc_page, &backing[i]);
+
+		kref_put(&encl_page->encl->refcount, sgx_encl_release);
+		epc_page->flags &= ~SGX_EPC_PAGE_RECLAIMER_TRACKED;
+
+		sgx_free_epc_page(epc_page);
+	}
+}
+
+static bool sgx_should_reclaim(unsigned long watermark)
+{
+	return atomic_long_read(&sgx_nr_free_pages) < watermark &&
+	       !list_empty(&sgx_active_page_list);
+}
+
+/*
+ * sgx_reclaim_direct() should be called (without enclave's mutex held)
+ * in locations where SGX memory resources might be low and might be
+ * needed in order to make forward progress.
+ */
+void sgx_reclaim_direct(void)
+{
+	if (sgx_should_reclaim(SGX_NR_LOW_PAGES))
+		sgx_reclaim_pages();
+}
+
+static int ksgxd(void *p)
+{
+	set_freezable();
+
+	/*
+	 * Sanitize pages in order to recover from kexec(). The 2nd pass is
+	 * required for SECS pages, whose child pages blocked EREMOVE.
+	 */
+	__sgx_sanitize_pages(&sgx_dirty_page_list);
+	WARN_ON(__sgx_sanitize_pages(&sgx_dirty_page_list));
+
+	while (!kthread_should_stop()) {
+		if (try_to_freeze())
+			continue;
+
+		wait_event_freezable(ksgxd_waitq,
+				     kthread_should_stop() ||
+				     sgx_should_reclaim(SGX_NR_HIGH_PAGES));
+
+		if (sgx_should_reclaim(SGX_NR_HIGH_PAGES))
+			sgx_reclaim_pages();
+
+		cond_resched();
+	}
+
+	return 0;
+}
+
+static bool __init sgx_page_reclaimer_init(void)
+{
+	struct task_struct *tsk;
+
+	tsk = kthread_run(ksgxd, NULL, "ksgxd");
+	if (IS_ERR(tsk))
+		return false;
+
+	ksgxd_tsk = tsk;
+
+	return true;
+}
+
+bool current_is_ksgxd(void)
+{
+	return current == ksgxd_tsk;
+}
+
+static struct sgx_epc_page *__sgx_alloc_epc_page_from_node(int nid)
+{
+	struct sgx_numa_node *node = &sgx_numa_nodes[nid];
+	struct sgx_epc_page *page = NULL;
+
+	spin_lock(&node->lock);
+
+	if (list_empty(&node->free_page_list)) {
+		spin_unlock(&node->lock);
+		return NULL;
+	}
+
+	page = list_first_entry(&node->free_page_list, struct sgx_epc_page, list);
+	list_del_init(&page->list);
+	page->flags = 0;
+
+	spin_unlock(&node->lock);
+	atomic_long_dec(&sgx_nr_free_pages);
+
+	return page;
+}
+
+/**
+ * __sgx_alloc_epc_page() - Allocate an EPC page
+ *
+ * Iterate through NUMA nodes and reserve ia free EPC page to the caller. Start
+ * from the NUMA node, where the caller is executing.
+ *
+ * Return:
+ * - an EPC page:	A borrowed EPC pages were available.
+ * - NULL:		Out of EPC pages.
+ */
+struct sgx_epc_page *__sgx_alloc_epc_page(void)
+{
+	struct sgx_epc_page *page;
+	int nid_of_current = numa_node_id();
+	int nid = nid_of_current;
+
+	if (node_isset(nid_of_current, sgx_numa_mask)) {
+		page = __sgx_alloc_epc_page_from_node(nid_of_current);
+		if (page)
+			return page;
+	}
+
+	/* Fall back to the non-local NUMA nodes: */
+	while (true) {
+		nid = next_node_in(nid, sgx_numa_mask);
+		if (nid == nid_of_current)
+			break;
+
+		page = __sgx_alloc_epc_page_from_node(nid);
+		if (page)
+			return page;
+	}
+
+	return ERR_PTR(-ENOMEM);
+}
+
+/**
+ * sgx_mark_page_reclaimable() - Mark a page as reclaimable
+ * @page:	EPC page
+ *
+ * Mark a page as reclaimable and add it to the active page list. Pages
+ * are automatically removed from the active list when freed.
+ */
+void sgx_mark_page_reclaimable(struct sgx_epc_page *page)
+{
+	spin_lock(&sgx_reclaimer_lock);
+	page->flags |= SGX_EPC_PAGE_RECLAIMER_TRACKED;
+	list_add_tail(&page->list, &sgx_active_page_list);
+	spin_unlock(&sgx_reclaimer_lock);
+}
+
+/**
+ * sgx_unmark_page_reclaimable() - Remove a page from the reclaim list
+ * @page:	EPC page
+ *
+ * Clear the reclaimable flag and remove the page from the active page list.
+ *
+ * Return:
+ *   0 on success,
+ *   -EBUSY if the page is in the process of being reclaimed
+ */
+int sgx_unmark_page_reclaimable(struct sgx_epc_page *page)
+{
+	spin_lock(&sgx_reclaimer_lock);
+	if (page->flags & SGX_EPC_PAGE_RECLAIMER_TRACKED) {
+		/* The page is being reclaimed. */
+		if (list_empty(&page->list)) {
+			spin_unlock(&sgx_reclaimer_lock);
+			return -EBUSY;
+		}
+
+		list_del(&page->list);
+		page->flags &= ~SGX_EPC_PAGE_RECLAIMER_TRACKED;
+	}
+	spin_unlock(&sgx_reclaimer_lock);
+
+	return 0;
+}
+
+/**
+ * sgx_alloc_epc_page() - Allocate an EPC page
+ * @owner:	the owner of the EPC page
+ * @reclaim:	reclaim pages if necessary
+ *
+ * Iterate through EPC sections and borrow a free EPC page to the caller. When a
+ * page is no longer needed it must be released with sgx_free_epc_page(). If
+ * @reclaim is set to true, directly reclaim pages when we are out of pages. No
+ * mm's can be locked when @reclaim is set to true.
+ *
+ * Finally, wake up ksgxd when the number of pages goes below the watermark
+ * before returning back to the caller.
+ *
+ * Return:
+ *   an EPC page,
+ *   -errno on error
+ */
+struct sgx_epc_page *sgx_alloc_epc_page(void *owner, bool reclaim)
+{
+	struct sgx_epc_page *page;
+
+	for ( ; ; ) {
+		page = __sgx_alloc_epc_page();
+		if (!IS_ERR(page)) {
+			page->owner = owner;
+			break;
+		}
+
+		if (list_empty(&sgx_active_page_list))
+			return ERR_PTR(-ENOMEM);
+
+		if (!reclaim) {
+			page = ERR_PTR(-EBUSY);
+			break;
+		}
+
+		if (signal_pending(current)) {
+			page = ERR_PTR(-ERESTARTSYS);
+			break;
+		}
+
+		sgx_reclaim_pages();
+		cond_resched();
+	}
+
+	if (sgx_should_reclaim(SGX_NR_LOW_PAGES))
+		wake_up(&ksgxd_waitq);
+
+	return page;
+}
+
+/**
+ * sgx_free_epc_page() - Free an EPC page
+ * @page:	an EPC page
+ *
+ * Put the EPC page back to the list of free pages. It's the caller's
+ * responsibility to make sure that the page is in uninitialized state. In other
+ * words, do EREMOVE, EWB or whatever operation is necessary before calling
+ * this function.
+ */
+void sgx_free_epc_page(struct sgx_epc_page *page)
+{
+	struct sgx_epc_section *section = &sgx_epc_sections[page->section];
+	struct sgx_numa_node *node = section->node;
+
+	spin_lock(&node->lock);
+
+	page->owner = NULL;
+	if (page->poison)
+		list_add(&page->list, &node->sgx_poison_page_list);
+	else
+		list_add_tail(&page->list, &node->free_page_list);
+	page->flags = SGX_EPC_PAGE_IS_FREE;
+
+	spin_unlock(&node->lock);
+	atomic_long_inc(&sgx_nr_free_pages);
+}
+
+static bool __init sgx_setup_epc_section(u64 phys_addr, u64 size,
+					 unsigned long index,
+					 struct sgx_epc_section *section)
+{
+	unsigned long nr_pages = size >> PAGE_SHIFT;
+	unsigned long i;
+
+	section->virt_addr = memremap(phys_addr, size, MEMREMAP_WB);
+	if (!section->virt_addr)
+		return false;
+
+	section->pages = vmalloc(nr_pages * sizeof(struct sgx_epc_page));
+	if (!section->pages) {
+		memunmap(section->virt_addr);
+		return false;
+	}
+
+	section->phys_addr = phys_addr;
+	xa_store_range(&sgx_epc_address_space, section->phys_addr,
+		       phys_addr + size - 1, section, GFP_KERNEL);
+
+	for (i = 0; i < nr_pages; i++) {
+		section->pages[i].section = index;
+		section->pages[i].flags = 0;
+		section->pages[i].owner = NULL;
+		section->pages[i].poison = 0;
+		list_add_tail(&section->pages[i].list, &sgx_dirty_page_list);
+	}
+
+	return true;
+}
+
+bool arch_is_platform_page(u64 paddr)
+{
+	return !!xa_load(&sgx_epc_address_space, paddr);
+}
+EXPORT_SYMBOL_GPL(arch_is_platform_page);
+
+static struct sgx_epc_page *sgx_paddr_to_page(u64 paddr)
+{
+	struct sgx_epc_section *section;
+
+	section = xa_load(&sgx_epc_address_space, paddr);
+	if (!section)
+		return NULL;
+
+	return &section->pages[PFN_DOWN(paddr - section->phys_addr)];
+}
+
+/*
+ * Called in process context to handle a hardware reported
+ * error in an SGX EPC page.
+ * If the MF_ACTION_REQUIRED bit is set in flags, then the
+ * context is the task that consumed the poison data. Otherwise
+ * this is called from a kernel thread unrelated to the page.
+ */
+int arch_memory_failure(unsigned long pfn, int flags)
+{
+	struct sgx_epc_page *page = sgx_paddr_to_page(pfn << PAGE_SHIFT);
+	struct sgx_epc_section *section;
+	struct sgx_numa_node *node;
+
+	/*
+	 * mm/memory-failure.c calls this routine for all errors
+	 * where there isn't a "struct page" for the address. But that
+	 * includes other address ranges besides SGX.
+	 */
+	if (!page)
+		return -ENXIO;
+
+	/*
+	 * If poison was consumed synchronously. Send a SIGBUS to
+	 * the task. Hardware has already exited the SGX enclave and
+	 * will not allow re-entry to an enclave that has a memory
+	 * error. The signal may help the task understand why the
+	 * enclave is broken.
+	 */
+	if (flags & MF_ACTION_REQUIRED)
+		force_sig(SIGBUS);
+
+	section = &sgx_epc_sections[page->section];
+	node = section->node;
+
+	spin_lock(&node->lock);
+
+	/* Already poisoned? Nothing more to do */
+	if (page->poison)
+		goto out;
+
+	page->poison = 1;
+
+	/*
+	 * If the page is on a free list, move it to the per-node
+	 * poison page list.
+	 */
+	if (page->flags & SGX_EPC_PAGE_IS_FREE) {
+		list_move(&page->list, &node->sgx_poison_page_list);
+		goto out;
+	}
+
+	/*
+	 * TBD: Add additional plumbing to enable pre-emptive
+	 * action for asynchronous poison notification. Until
+	 * then just hope that the poison:
+	 * a) is not accessed - sgx_free_epc_page() will deal with it
+	 *    when the user gives it back
+	 * b) results in a recoverable machine check rather than
+	 *    a fatal one
+	 */
+out:
+	spin_unlock(&node->lock);
+	return 0;
+}
+
+/**
+ * A section metric is concatenated in a way that @low bits 12-31 define the
+ * bits 12-31 of the metric and @high bits 0-19 define the bits 32-51 of the
+ * metric.
+ */
+static inline u64 __init sgx_calc_section_metric(u64 low, u64 high)
+{
+	return (low & GENMASK_ULL(31, 12)) +
+	       ((high & GENMASK_ULL(19, 0)) << 32);
+}
+
+#ifdef CONFIG_NUMA
+static ssize_t sgx_total_bytes_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "%lu\n", sgx_numa_nodes[dev->id].size);
+}
+static DEVICE_ATTR_RO(sgx_total_bytes);
+
+static umode_t arch_node_attr_is_visible(struct kobject *kobj,
+		struct attribute *attr, int idx)
+{
+	/* Make all x86/ attributes invisible when SGX is not initialized: */
+	if (nodes_empty(sgx_numa_mask))
+		return 0;
+
+	return attr->mode;
+}
+
+static struct attribute *arch_node_dev_attrs[] = {
+	&dev_attr_sgx_total_bytes.attr,
+	NULL,
+};
+
+const struct attribute_group arch_node_dev_group = {
+	.name = "x86",
+	.attrs = arch_node_dev_attrs,
+	.is_visible = arch_node_attr_is_visible,
+};
+
+static void __init arch_update_sysfs_visibility(int nid)
+{
+	struct node *node = node_devices[nid];
+	int ret;
+
+	ret = sysfs_update_group(&node->dev.kobj, &arch_node_dev_group);
+
+	if (ret)
+		pr_err("sysfs update failed (%d), files may be invisible", ret);
+}
+#else /* !CONFIG_NUMA */
+static void __init arch_update_sysfs_visibility(int nid) {}
+#endif
+
+static bool __init sgx_page_cache_init(void)
+{
+	u32 eax, ebx, ecx, edx, type;
+	u64 pa, size;
+	int nid;
+	int i;
+
+	sgx_numa_nodes = kmalloc_array(num_possible_nodes(), sizeof(*sgx_numa_nodes), GFP_KERNEL);
+	if (!sgx_numa_nodes)
+		return false;
+
+	for (i = 0; i < ARRAY_SIZE(sgx_epc_sections); i++) {
+		cpuid_count(SGX_CPUID, i + SGX_CPUID_EPC, &eax, &ebx, &ecx, &edx);
+
+		type = eax & SGX_CPUID_EPC_MASK;
+		if (type == SGX_CPUID_EPC_INVALID)
+			break;
+
+		if (type != SGX_CPUID_EPC_SECTION) {
+			pr_err_once("Unknown EPC section type: %u\n", type);
+			break;
+		}
+
+		pa   = sgx_calc_section_metric(eax, ebx);
+		size = sgx_calc_section_metric(ecx, edx);
+
+		pr_info("EPC section 0x%llx-0x%llx\n", pa, pa + size - 1);
+
+		if (!sgx_setup_epc_section(pa, size, i, &sgx_epc_sections[i])) {
+			pr_err("No free memory for an EPC section\n");
+			break;
+		}
+
+		nid = numa_map_to_online_node(phys_to_target_node(pa));
+		if (nid == NUMA_NO_NODE) {
+			/* The physical address is already printed above. */
+			pr_warn(FW_BUG "Unable to map EPC section to online node. Fallback to the NUMA node 0.\n");
+			nid = 0;
+		}
+
+		if (!node_isset(nid, sgx_numa_mask)) {
+			spin_lock_init(&sgx_numa_nodes[nid].lock);
+			INIT_LIST_HEAD(&sgx_numa_nodes[nid].free_page_list);
+			INIT_LIST_HEAD(&sgx_numa_nodes[nid].sgx_poison_page_list);
+			node_set(nid, sgx_numa_mask);
+			sgx_numa_nodes[nid].size = 0;
+
+			/* Make SGX-specific node sysfs files visible: */
+			arch_update_sysfs_visibility(nid);
+		}
+
+		sgx_epc_sections[i].node =  &sgx_numa_nodes[nid];
+		sgx_numa_nodes[nid].size += size;
+
+		sgx_nr_epc_sections++;
+	}
+
+	if (!sgx_nr_epc_sections) {
+		pr_err("There are zero EPC sections.\n");
+		return false;
+	}
+
+	return true;
+}
+
+/*
+ * Update the SGX_LEPUBKEYHASH MSRs to the values specified by caller.
+ * Bare-metal driver requires to update them to hash of enclave's signer
+ * before EINIT. KVM needs to update them to guest's virtual MSR values
+ * before doing EINIT from guest.
+ */
+void sgx_update_lepubkeyhash(u64 *lepubkeyhash)
+{
+	int i;
+
+	WARN_ON_ONCE(preemptible());
+
+	for (i = 0; i < 4; i++)
+		wrmsrl(MSR_IA32_SGXLEPUBKEYHASH0 + i, lepubkeyhash[i]);
+}
+
+const struct file_operations sgx_provision_fops = {
+	.owner			= THIS_MODULE,
+};
+
+static struct miscdevice sgx_dev_provision = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = "sgx_provision",
+	.nodename = "sgx_provision",
+	.fops = &sgx_provision_fops,
+};
+
+/**
+ * sgx_set_attribute() - Update allowed attributes given file descriptor
+ * @allowed_attributes:		Pointer to allowed enclave attributes
+ * @attribute_fd:		File descriptor for specific attribute
+ *
+ * Append enclave attribute indicated by file descriptor to allowed
+ * attributes. Currently only SGX_ATTR_PROVISIONKEY indicated by
+ * /dev/sgx_provision is supported.
+ *
+ * Return:
+ * -0:		SGX_ATTR_PROVISIONKEY is appended to allowed_attributes
+ * -EINVAL:	Invalid, or not supported file descriptor
+ */
+int sgx_set_attribute(unsigned long *allowed_attributes,
+		      unsigned int attribute_fd)
+{
+	struct fd f = fdget(attribute_fd);
+
+	if (!f.file)
+		return -EINVAL;
+
+	if (f.file->f_op != &sgx_provision_fops) {
+		fdput(f);
+		return -EINVAL;
+	}
+
+	*allowed_attributes |= SGX_ATTR_PROVISIONKEY;
+
+	fdput(f);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(sgx_set_attribute);
+
+static int __init sgx_init(void)
+{
+	int ret;
+	int i;
+
+	if (!cpu_feature_enabled(X86_FEATURE_SGX))
+		return -ENODEV;
+
+	if (!sgx_page_cache_init())
+		return -ENOMEM;
+
+	if (!sgx_page_reclaimer_init()) {
+		ret = -ENOMEM;
+		goto err_page_cache;
+	}
+
+	ret = misc_register(&sgx_dev_provision);
+	if (ret)
+		goto err_kthread;
+
+	/*
+	 * Always try to initialize the native *and* KVM drivers.
+	 * The KVM driver is less picky than the native one and
+	 * can function if the native one is not supported on the
+	 * current system or fails to initialize.
+	 *
+	 * Error out only if both fail to initialize.
+	 */
+	ret = sgx_drv_init();
+
+	if (sgx_vepc_init() && ret)
+		goto err_provision;
+
+	return 0;
+
+err_provision:
+	misc_deregister(&sgx_dev_provision);
+
+err_kthread:
+	kthread_stop(ksgxd_tsk);
+
+err_page_cache:
+	for (i = 0; i < sgx_nr_epc_sections; i++) {
+		vfree(sgx_epc_sections[i].pages);
+		memunmap(sgx_epc_sections[i].virt_addr);
+	}
+
+	return ret;
+}
+
+device_initcall(sgx_init);
diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h
new file mode 100644
index 0000000000..d2dad21259
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/sgx.h
@@ -0,0 +1,107 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _X86_SGX_H
+#define _X86_SGX_H
+
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/rwsem.h>
+#include <linux/types.h>
+#include <asm/asm.h>
+#include <asm/sgx.h>
+
+#undef pr_fmt
+#define pr_fmt(fmt) "sgx: " fmt
+
+#define EREMOVE_ERROR_MESSAGE \
+	"EREMOVE returned %d (0x%x) and an EPC page was leaked. SGX may become unusable. " \
+	"Refer to Documentation/arch/x86/sgx.rst for more information."
+
+#define SGX_MAX_EPC_SECTIONS		8
+#define SGX_EEXTEND_BLOCK_SIZE		256
+#define SGX_NR_TO_SCAN			16
+#define SGX_NR_LOW_PAGES		32
+#define SGX_NR_HIGH_PAGES		64
+
+/* Pages, which are being tracked by the page reclaimer. */
+#define SGX_EPC_PAGE_RECLAIMER_TRACKED	BIT(0)
+
+/* Pages on free list */
+#define SGX_EPC_PAGE_IS_FREE		BIT(1)
+
+struct sgx_epc_page {
+	unsigned int section;
+	u16 flags;
+	u16 poison;
+	struct sgx_encl_page *owner;
+	struct list_head list;
+};
+
+/*
+ * Contains the tracking data for NUMA nodes having EPC pages. Most importantly,
+ * the free page list local to the node is stored here.
+ */
+struct sgx_numa_node {
+	struct list_head free_page_list;
+	struct list_head sgx_poison_page_list;
+	unsigned long size;
+	spinlock_t lock;
+};
+
+/*
+ * The firmware can define multiple chunks of EPC to the different areas of the
+ * physical memory e.g. for memory areas of the each node. This structure is
+ * used to store EPC pages for one EPC section and virtual memory area where
+ * the pages have been mapped.
+ */
+struct sgx_epc_section {
+	unsigned long phys_addr;
+	void *virt_addr;
+	struct sgx_epc_page *pages;
+	struct sgx_numa_node *node;
+};
+
+extern struct sgx_epc_section sgx_epc_sections[SGX_MAX_EPC_SECTIONS];
+
+static inline unsigned long sgx_get_epc_phys_addr(struct sgx_epc_page *page)
+{
+	struct sgx_epc_section *section = &sgx_epc_sections[page->section];
+	unsigned long index;
+
+	index = ((unsigned long)page - (unsigned long)section->pages) / sizeof(*page);
+
+	return section->phys_addr + index * PAGE_SIZE;
+}
+
+static inline void *sgx_get_epc_virt_addr(struct sgx_epc_page *page)
+{
+	struct sgx_epc_section *section = &sgx_epc_sections[page->section];
+	unsigned long index;
+
+	index = ((unsigned long)page - (unsigned long)section->pages) / sizeof(*page);
+
+	return section->virt_addr + index * PAGE_SIZE;
+}
+
+struct sgx_epc_page *__sgx_alloc_epc_page(void);
+void sgx_free_epc_page(struct sgx_epc_page *page);
+
+void sgx_reclaim_direct(void);
+void sgx_mark_page_reclaimable(struct sgx_epc_page *page);
+int sgx_unmark_page_reclaimable(struct sgx_epc_page *page);
+struct sgx_epc_page *sgx_alloc_epc_page(void *owner, bool reclaim);
+
+void sgx_ipi_cb(void *info);
+
+#ifdef CONFIG_X86_SGX_KVM
+int __init sgx_vepc_init(void);
+#else
+static inline int __init sgx_vepc_init(void)
+{
+	return -ENODEV;
+}
+#endif
+
+void sgx_update_lepubkeyhash(u64 *lepubkeyhash);
+
+#endif /* _X86_SGX_H */
diff --git a/arch/x86/kernel/cpu/sgx/virt.c b/arch/x86/kernel/cpu/sgx/virt.c
new file mode 100644
index 0000000000..7aaa3652e3
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/virt.c
@@ -0,0 +1,435 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Device driver to expose SGX enclave memory to KVM guests.
+ *
+ * Copyright(c) 2021 Intel Corporation.
+ */
+
+#include <linux/miscdevice.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/sched/mm.h>
+#include <linux/sched/signal.h>
+#include <linux/slab.h>
+#include <linux/xarray.h>
+#include <asm/sgx.h>
+#include <uapi/asm/sgx.h>
+
+#include "encls.h"
+#include "sgx.h"
+
+struct sgx_vepc {
+	struct xarray page_array;
+	struct mutex lock;
+};
+
+/*
+ * Temporary SECS pages that cannot be EREMOVE'd due to having child in other
+ * virtual EPC instances, and the lock to protect it.
+ */
+static struct mutex zombie_secs_pages_lock;
+static struct list_head zombie_secs_pages;
+
+static int __sgx_vepc_fault(struct sgx_vepc *vepc,
+			    struct vm_area_struct *vma, unsigned long addr)
+{
+	struct sgx_epc_page *epc_page;
+	unsigned long index, pfn;
+	int ret;
+
+	WARN_ON(!mutex_is_locked(&vepc->lock));
+
+	/* Calculate index of EPC page in virtual EPC's page_array */
+	index = vma->vm_pgoff + PFN_DOWN(addr - vma->vm_start);
+
+	epc_page = xa_load(&vepc->page_array, index);
+	if (epc_page)
+		return 0;
+
+	epc_page = sgx_alloc_epc_page(vepc, false);
+	if (IS_ERR(epc_page))
+		return PTR_ERR(epc_page);
+
+	ret = xa_err(xa_store(&vepc->page_array, index, epc_page, GFP_KERNEL));
+	if (ret)
+		goto err_free;
+
+	pfn = PFN_DOWN(sgx_get_epc_phys_addr(epc_page));
+
+	ret = vmf_insert_pfn(vma, addr, pfn);
+	if (ret != VM_FAULT_NOPAGE) {
+		ret = -EFAULT;
+		goto err_delete;
+	}
+
+	return 0;
+
+err_delete:
+	xa_erase(&vepc->page_array, index);
+err_free:
+	sgx_free_epc_page(epc_page);
+	return ret;
+}
+
+static vm_fault_t sgx_vepc_fault(struct vm_fault *vmf)
+{
+	struct vm_area_struct *vma = vmf->vma;
+	struct sgx_vepc *vepc = vma->vm_private_data;
+	int ret;
+
+	mutex_lock(&vepc->lock);
+	ret = __sgx_vepc_fault(vepc, vma, vmf->address);
+	mutex_unlock(&vepc->lock);
+
+	if (!ret)
+		return VM_FAULT_NOPAGE;
+
+	if (ret == -EBUSY && (vmf->flags & FAULT_FLAG_ALLOW_RETRY)) {
+		mmap_read_unlock(vma->vm_mm);
+		return VM_FAULT_RETRY;
+	}
+
+	return VM_FAULT_SIGBUS;
+}
+
+static const struct vm_operations_struct sgx_vepc_vm_ops = {
+	.fault = sgx_vepc_fault,
+};
+
+static int sgx_vepc_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct sgx_vepc *vepc = file->private_data;
+
+	if (!(vma->vm_flags & VM_SHARED))
+		return -EINVAL;
+
+	vma->vm_ops = &sgx_vepc_vm_ops;
+	/* Don't copy VMA in fork() */
+	vm_flags_set(vma, VM_PFNMAP | VM_IO | VM_DONTDUMP | VM_DONTCOPY);
+	vma->vm_private_data = vepc;
+
+	return 0;
+}
+
+static int sgx_vepc_remove_page(struct sgx_epc_page *epc_page)
+{
+	/*
+	 * Take a previously guest-owned EPC page and return it to the
+	 * general EPC page pool.
+	 *
+	 * Guests can not be trusted to have left this page in a good
+	 * state, so run EREMOVE on the page unconditionally.  In the
+	 * case that a guest properly EREMOVE'd this page, a superfluous
+	 * EREMOVE is harmless.
+	 */
+	return __eremove(sgx_get_epc_virt_addr(epc_page));
+}
+
+static int sgx_vepc_free_page(struct sgx_epc_page *epc_page)
+{
+	int ret = sgx_vepc_remove_page(epc_page);
+	if (ret) {
+		/*
+		 * Only SGX_CHILD_PRESENT is expected, which is because of
+		 * EREMOVE'ing an SECS still with child, in which case it can
+		 * be handled by EREMOVE'ing the SECS again after all pages in
+		 * virtual EPC have been EREMOVE'd. See comments in below in
+		 * sgx_vepc_release().
+		 *
+		 * The user of virtual EPC (KVM) needs to guarantee there's no
+		 * logical processor is still running in the enclave in guest,
+		 * otherwise EREMOVE will get SGX_ENCLAVE_ACT which cannot be
+		 * handled here.
+		 */
+		WARN_ONCE(ret != SGX_CHILD_PRESENT, EREMOVE_ERROR_MESSAGE,
+			  ret, ret);
+		return ret;
+	}
+
+	sgx_free_epc_page(epc_page);
+	return 0;
+}
+
+static long sgx_vepc_remove_all(struct sgx_vepc *vepc)
+{
+	struct sgx_epc_page *entry;
+	unsigned long index;
+	long failures = 0;
+
+	xa_for_each(&vepc->page_array, index, entry) {
+		int ret = sgx_vepc_remove_page(entry);
+		if (ret) {
+			if (ret == SGX_CHILD_PRESENT) {
+				/* The page is a SECS, userspace will retry.  */
+				failures++;
+			} else {
+				/*
+				 * Report errors due to #GP or SGX_ENCLAVE_ACT; do not
+				 * WARN, as userspace can induce said failures by
+				 * calling the ioctl concurrently on multiple vEPCs or
+				 * while one or more CPUs is running the enclave.  Only
+				 * a #PF on EREMOVE indicates a kernel/hardware issue.
+				 */
+				WARN_ON_ONCE(encls_faulted(ret) &&
+					     ENCLS_TRAPNR(ret) != X86_TRAP_GP);
+				return -EBUSY;
+			}
+		}
+		cond_resched();
+	}
+
+	/*
+	 * Return the number of SECS pages that failed to be removed, so
+	 * userspace knows that it has to retry.
+	 */
+	return failures;
+}
+
+static int sgx_vepc_release(struct inode *inode, struct file *file)
+{
+	struct sgx_vepc *vepc = file->private_data;
+	struct sgx_epc_page *epc_page, *tmp, *entry;
+	unsigned long index;
+
+	LIST_HEAD(secs_pages);
+
+	xa_for_each(&vepc->page_array, index, entry) {
+		/*
+		 * Remove all normal, child pages.  sgx_vepc_free_page()
+		 * will fail if EREMOVE fails, but this is OK and expected on
+		 * SECS pages.  Those can only be EREMOVE'd *after* all their
+		 * child pages. Retries below will clean them up.
+		 */
+		if (sgx_vepc_free_page(entry))
+			continue;
+
+		xa_erase(&vepc->page_array, index);
+		cond_resched();
+	}
+
+	/*
+	 * Retry EREMOVE'ing pages.  This will clean up any SECS pages that
+	 * only had children in this 'epc' area.
+	 */
+	xa_for_each(&vepc->page_array, index, entry) {
+		epc_page = entry;
+		/*
+		 * An EREMOVE failure here means that the SECS page still
+		 * has children.  But, since all children in this 'sgx_vepc'
+		 * have been removed, the SECS page must have a child on
+		 * another instance.
+		 */
+		if (sgx_vepc_free_page(epc_page))
+			list_add_tail(&epc_page->list, &secs_pages);
+
+		xa_erase(&vepc->page_array, index);
+		cond_resched();
+	}
+
+	/*
+	 * SECS pages are "pinned" by child pages, and "unpinned" once all
+	 * children have been EREMOVE'd.  A child page in this instance
+	 * may have pinned an SECS page encountered in an earlier release(),
+	 * creating a zombie.  Since some children were EREMOVE'd above,
+	 * try to EREMOVE all zombies in the hopes that one was unpinned.
+	 */
+	mutex_lock(&zombie_secs_pages_lock);
+	list_for_each_entry_safe(epc_page, tmp, &zombie_secs_pages, list) {
+		/*
+		 * Speculatively remove the page from the list of zombies,
+		 * if the page is successfully EREMOVE'd it will be added to
+		 * the list of free pages.  If EREMOVE fails, throw the page
+		 * on the local list, which will be spliced on at the end.
+		 */
+		list_del(&epc_page->list);
+
+		if (sgx_vepc_free_page(epc_page))
+			list_add_tail(&epc_page->list, &secs_pages);
+		cond_resched();
+	}
+
+	if (!list_empty(&secs_pages))
+		list_splice_tail(&secs_pages, &zombie_secs_pages);
+	mutex_unlock(&zombie_secs_pages_lock);
+
+	xa_destroy(&vepc->page_array);
+	kfree(vepc);
+
+	return 0;
+}
+
+static int sgx_vepc_open(struct inode *inode, struct file *file)
+{
+	struct sgx_vepc *vepc;
+
+	vepc = kzalloc(sizeof(struct sgx_vepc), GFP_KERNEL);
+	if (!vepc)
+		return -ENOMEM;
+	mutex_init(&vepc->lock);
+	xa_init(&vepc->page_array);
+
+	file->private_data = vepc;
+
+	return 0;
+}
+
+static long sgx_vepc_ioctl(struct file *file,
+			   unsigned int cmd, unsigned long arg)
+{
+	struct sgx_vepc *vepc = file->private_data;
+
+	switch (cmd) {
+	case SGX_IOC_VEPC_REMOVE_ALL:
+		if (arg)
+			return -EINVAL;
+		return sgx_vepc_remove_all(vepc);
+
+	default:
+		return -ENOTTY;
+	}
+}
+
+static const struct file_operations sgx_vepc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= sgx_vepc_open,
+	.unlocked_ioctl	= sgx_vepc_ioctl,
+	.compat_ioctl	= sgx_vepc_ioctl,
+	.release	= sgx_vepc_release,
+	.mmap		= sgx_vepc_mmap,
+};
+
+static struct miscdevice sgx_vepc_dev = {
+	.minor		= MISC_DYNAMIC_MINOR,
+	.name		= "sgx_vepc",
+	.nodename	= "sgx_vepc",
+	.fops		= &sgx_vepc_fops,
+};
+
+int __init sgx_vepc_init(void)
+{
+	/* SGX virtualization requires KVM to work */
+	if (!cpu_feature_enabled(X86_FEATURE_VMX))
+		return -ENODEV;
+
+	INIT_LIST_HEAD(&zombie_secs_pages);
+	mutex_init(&zombie_secs_pages_lock);
+
+	return misc_register(&sgx_vepc_dev);
+}
+
+/**
+ * sgx_virt_ecreate() - Run ECREATE on behalf of guest
+ * @pageinfo:	Pointer to PAGEINFO structure
+ * @secs:	Userspace pointer to SECS page
+ * @trapnr:	trap number injected to guest in case of ECREATE error
+ *
+ * Run ECREATE on behalf of guest after KVM traps ECREATE for the purpose
+ * of enforcing policies of guest's enclaves, and return the trap number
+ * which should be injected to guest in case of any ECREATE error.
+ *
+ * Return:
+ * -  0:	ECREATE was successful.
+ * - <0:	on error.
+ */
+int sgx_virt_ecreate(struct sgx_pageinfo *pageinfo, void __user *secs,
+		     int *trapnr)
+{
+	int ret;
+
+	/*
+	 * @secs is an untrusted, userspace-provided address.  It comes from
+	 * KVM and is assumed to be a valid pointer which points somewhere in
+	 * userspace.  This can fault and call SGX or other fault handlers when
+	 * userspace mapping @secs doesn't exist.
+	 *
+	 * Add a WARN() to make sure @secs is already valid userspace pointer
+	 * from caller (KVM), who should already have handled invalid pointer
+	 * case (for instance, made by malicious guest).  All other checks,
+	 * such as alignment of @secs, are deferred to ENCLS itself.
+	 */
+	if (WARN_ON_ONCE(!access_ok(secs, PAGE_SIZE)))
+		return -EINVAL;
+
+	__uaccess_begin();
+	ret = __ecreate(pageinfo, (void *)secs);
+	__uaccess_end();
+
+	if (encls_faulted(ret)) {
+		*trapnr = ENCLS_TRAPNR(ret);
+		return -EFAULT;
+	}
+
+	/* ECREATE doesn't return an error code, it faults or succeeds. */
+	WARN_ON_ONCE(ret);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(sgx_virt_ecreate);
+
+static int __sgx_virt_einit(void __user *sigstruct, void __user *token,
+			    void __user *secs)
+{
+	int ret;
+
+	/*
+	 * Make sure all userspace pointers from caller (KVM) are valid.
+	 * All other checks deferred to ENCLS itself.  Also see comment
+	 * for @secs in sgx_virt_ecreate().
+	 */
+#define SGX_EINITTOKEN_SIZE	304
+	if (WARN_ON_ONCE(!access_ok(sigstruct, sizeof(struct sgx_sigstruct)) ||
+			 !access_ok(token, SGX_EINITTOKEN_SIZE) ||
+			 !access_ok(secs, PAGE_SIZE)))
+		return -EINVAL;
+
+	__uaccess_begin();
+	ret = __einit((void *)sigstruct, (void *)token, (void *)secs);
+	__uaccess_end();
+
+	return ret;
+}
+
+/**
+ * sgx_virt_einit() - Run EINIT on behalf of guest
+ * @sigstruct:		Userspace pointer to SIGSTRUCT structure
+ * @token:		Userspace pointer to EINITTOKEN structure
+ * @secs:		Userspace pointer to SECS page
+ * @lepubkeyhash:	Pointer to guest's *virtual* SGX_LEPUBKEYHASH MSR values
+ * @trapnr:		trap number injected to guest in case of EINIT error
+ *
+ * Run EINIT on behalf of guest after KVM traps EINIT. If SGX_LC is available
+ * in host, SGX driver may rewrite the hardware values at wish, therefore KVM
+ * needs to update hardware values to guest's virtual MSR values in order to
+ * ensure EINIT is executed with expected hardware values.
+ *
+ * Return:
+ * -  0:	EINIT was successful.
+ * - <0:	on error.
+ */
+int sgx_virt_einit(void __user *sigstruct, void __user *token,
+		   void __user *secs, u64 *lepubkeyhash, int *trapnr)
+{
+	int ret;
+
+	if (!cpu_feature_enabled(X86_FEATURE_SGX_LC)) {
+		ret = __sgx_virt_einit(sigstruct, token, secs);
+	} else {
+		preempt_disable();
+
+		sgx_update_lepubkeyhash(lepubkeyhash);
+
+		ret = __sgx_virt_einit(sigstruct, token, secs);
+		preempt_enable();
+	}
+
+	/* Propagate up the error from the WARN_ON_ONCE in __sgx_virt_einit() */
+	if (ret == -EINVAL)
+		return ret;
+
+	if (encls_faulted(ret)) {
+		*trapnr = ENCLS_TRAPNR(ret);
+		return -EFAULT;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(sgx_virt_einit);
diff --git a/arch/x86/kernel/cpu/topology.c b/arch/x86/kernel/cpu/topology.c
new file mode 100644
index 0000000000..0270925fe0
--- /dev/null
+++ b/arch/x86/kernel/cpu/topology.c
@@ -0,0 +1,168 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Check for extended topology enumeration cpuid leaf 0xb and if it
+ * exists, use it for populating initial_apicid and cpu topology
+ * detection.
+ */
+
+#include <linux/cpu.h>
+#include <asm/apic.h>
+#include <asm/memtype.h>
+#include <asm/processor.h>
+
+#include "cpu.h"
+
+/* leaf 0xb SMT level */
+#define SMT_LEVEL	0
+
+/* extended topology sub-leaf types */
+#define INVALID_TYPE	0
+#define SMT_TYPE	1
+#define CORE_TYPE	2
+#define DIE_TYPE	5
+
+#define LEAFB_SUBTYPE(ecx)		(((ecx) >> 8) & 0xff)
+#define BITS_SHIFT_NEXT_LEVEL(eax)	((eax) & 0x1f)
+#define LEVEL_MAX_SIBLINGS(ebx)		((ebx) & 0xffff)
+
+unsigned int __max_die_per_package __read_mostly = 1;
+EXPORT_SYMBOL(__max_die_per_package);
+
+#ifdef CONFIG_SMP
+/*
+ * Check if given CPUID extended topology "leaf" is implemented
+ */
+static int check_extended_topology_leaf(int leaf)
+{
+	unsigned int eax, ebx, ecx, edx;
+
+	cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
+
+	if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE))
+		return -1;
+
+	return 0;
+}
+/*
+ * Return best CPUID Extended Topology Leaf supported
+ */
+static int detect_extended_topology_leaf(struct cpuinfo_x86 *c)
+{
+	if (c->cpuid_level >= 0x1f) {
+		if (check_extended_topology_leaf(0x1f) == 0)
+			return 0x1f;
+	}
+
+	if (c->cpuid_level >= 0xb) {
+		if (check_extended_topology_leaf(0xb) == 0)
+			return 0xb;
+	}
+
+	return -1;
+}
+#endif
+
+int detect_extended_topology_early(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_SMP
+	unsigned int eax, ebx, ecx, edx;
+	int leaf;
+
+	leaf = detect_extended_topology_leaf(c);
+	if (leaf < 0)
+		return -1;
+
+	set_cpu_cap(c, X86_FEATURE_XTOPOLOGY);
+
+	cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
+	/*
+	 * initial apic id, which also represents 32-bit extended x2apic id.
+	 */
+	c->initial_apicid = edx;
+	smp_num_siblings = max_t(int, smp_num_siblings, LEVEL_MAX_SIBLINGS(ebx));
+#endif
+	return 0;
+}
+
+/*
+ * Check for extended topology enumeration cpuid leaf, and if it
+ * exists, use it for populating initial_apicid and cpu topology
+ * detection.
+ */
+int detect_extended_topology(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_SMP
+	unsigned int eax, ebx, ecx, edx, sub_index;
+	unsigned int ht_mask_width, core_plus_mask_width, die_plus_mask_width;
+	unsigned int core_select_mask, core_level_siblings;
+	unsigned int die_select_mask, die_level_siblings;
+	unsigned int pkg_mask_width;
+	bool die_level_present = false;
+	int leaf;
+
+	leaf = detect_extended_topology_leaf(c);
+	if (leaf < 0)
+		return -1;
+
+	/*
+	 * Populate HT related information from sub-leaf level 0.
+	 */
+	cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
+	c->initial_apicid = edx;
+	core_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
+	smp_num_siblings = max_t(int, smp_num_siblings, LEVEL_MAX_SIBLINGS(ebx));
+	core_plus_mask_width = ht_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
+	die_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
+	pkg_mask_width = die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
+
+	sub_index = 1;
+	while (true) {
+		cpuid_count(leaf, sub_index, &eax, &ebx, &ecx, &edx);
+
+		/*
+		 * Check for the Core type in the implemented sub leaves.
+		 */
+		if (LEAFB_SUBTYPE(ecx) == CORE_TYPE) {
+			core_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
+			core_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
+			die_level_siblings = core_level_siblings;
+			die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
+		}
+		if (LEAFB_SUBTYPE(ecx) == DIE_TYPE) {
+			die_level_present = true;
+			die_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
+			die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
+		}
+
+		if (LEAFB_SUBTYPE(ecx) != INVALID_TYPE)
+			pkg_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
+		else
+			break;
+
+		sub_index++;
+	}
+
+	core_select_mask = (~(-1 << pkg_mask_width)) >> ht_mask_width;
+	die_select_mask = (~(-1 << die_plus_mask_width)) >>
+				core_plus_mask_width;
+
+	c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid,
+				ht_mask_width) & core_select_mask;
+
+	if (die_level_present) {
+		c->cpu_die_id = apic->phys_pkg_id(c->initial_apicid,
+					core_plus_mask_width) & die_select_mask;
+	}
+
+	c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid,
+				pkg_mask_width);
+	/*
+	 * Reinit the apicid, now that we have extended initial_apicid.
+	 */
+	c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
+
+	c->x86_max_cores = (core_level_siblings / smp_num_siblings);
+	__max_die_per_package = (die_level_siblings / core_level_siblings);
+#endif
+	return 0;
+}
diff --git a/arch/x86/kernel/cpu/transmeta.c b/arch/x86/kernel/cpu/transmeta.c
new file mode 100644
index 0000000000..42c9398276
--- /dev/null
+++ b/arch/x86/kernel/cpu/transmeta.c
@@ -0,0 +1,111 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/sched/clock.h>
+#include <linux/mm.h>
+#include <asm/cpufeature.h>
+#include <asm/msr.h>
+#include "cpu.h"
+
+static void early_init_transmeta(struct cpuinfo_x86 *c)
+{
+	u32 xlvl;
+
+	/* Transmeta-defined flags: level 0x80860001 */
+	xlvl = cpuid_eax(0x80860000);
+	if ((xlvl & 0xffff0000) == 0x80860000) {
+		if (xlvl >= 0x80860001)
+			c->x86_capability[CPUID_8086_0001_EDX] = cpuid_edx(0x80860001);
+	}
+}
+
+static void init_transmeta(struct cpuinfo_x86 *c)
+{
+	unsigned int cap_mask, uk, max, dummy;
+	unsigned int cms_rev1, cms_rev2;
+	unsigned int cpu_rev, cpu_freq = 0, cpu_flags, new_cpu_rev;
+	char cpu_info[65];
+
+	early_init_transmeta(c);
+
+	cpu_detect_cache_sizes(c);
+
+	/* Print CMS and CPU revision */
+	max = cpuid_eax(0x80860000);
+	cpu_rev = 0;
+	if (max >= 0x80860001) {
+		cpuid(0x80860001, &dummy, &cpu_rev, &cpu_freq, &cpu_flags);
+		if (cpu_rev != 0x02000000) {
+			pr_info("CPU: Processor revision %u.%u.%u.%u, %u MHz\n",
+				(cpu_rev >> 24) & 0xff,
+				(cpu_rev >> 16) & 0xff,
+				(cpu_rev >> 8) & 0xff,
+				cpu_rev & 0xff,
+				cpu_freq);
+		}
+	}
+	if (max >= 0x80860002) {
+		cpuid(0x80860002, &new_cpu_rev, &cms_rev1, &cms_rev2, &dummy);
+		if (cpu_rev == 0x02000000) {
+			pr_info("CPU: Processor revision %08X, %u MHz\n",
+				new_cpu_rev, cpu_freq);
+		}
+		pr_info("CPU: Code Morphing Software revision %u.%u.%u-%u-%u\n",
+		       (cms_rev1 >> 24) & 0xff,
+		       (cms_rev1 >> 16) & 0xff,
+		       (cms_rev1 >> 8) & 0xff,
+		       cms_rev1 & 0xff,
+		       cms_rev2);
+	}
+	if (max >= 0x80860006) {
+		cpuid(0x80860003,
+		      (void *)&cpu_info[0],
+		      (void *)&cpu_info[4],
+		      (void *)&cpu_info[8],
+		      (void *)&cpu_info[12]);
+		cpuid(0x80860004,
+		      (void *)&cpu_info[16],
+		      (void *)&cpu_info[20],
+		      (void *)&cpu_info[24],
+		      (void *)&cpu_info[28]);
+		cpuid(0x80860005,
+		      (void *)&cpu_info[32],
+		      (void *)&cpu_info[36],
+		      (void *)&cpu_info[40],
+		      (void *)&cpu_info[44]);
+		cpuid(0x80860006,
+		      (void *)&cpu_info[48],
+		      (void *)&cpu_info[52],
+		      (void *)&cpu_info[56],
+		      (void *)&cpu_info[60]);
+		cpu_info[64] = '\0';
+		pr_info("CPU: %s\n", cpu_info);
+	}
+
+	/* Unhide possibly hidden capability flags */
+	rdmsr(0x80860004, cap_mask, uk);
+	wrmsr(0x80860004, ~0, uk);
+	c->x86_capability[CPUID_1_EDX] = cpuid_edx(0x00000001);
+	wrmsr(0x80860004, cap_mask, uk);
+
+	/* All Transmeta CPUs have a constant TSC */
+	set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
+
+#ifdef CONFIG_SYSCTL
+	/*
+	 * randomize_va_space slows us down enormously;
+	 * it probably triggers retranslation of x86->native bytecode
+	 */
+	randomize_va_space = 0;
+#endif
+}
+
+static const struct cpu_dev transmeta_cpu_dev = {
+	.c_vendor	= "Transmeta",
+	.c_ident	= { "GenuineTMx86", "TransmetaCPU" },
+	.c_early_init	= early_init_transmeta,
+	.c_init		= init_transmeta,
+	.c_x86_vendor	= X86_VENDOR_TRANSMETA,
+};
+
+cpu_dev_register(transmeta_cpu_dev);
diff --git a/arch/x86/kernel/cpu/tsx.c b/arch/x86/kernel/cpu/tsx.c
new file mode 100644
index 0000000000..b31ee4f165
--- /dev/null
+++ b/arch/x86/kernel/cpu/tsx.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel Transactional Synchronization Extensions (TSX) control.
+ *
+ * Copyright (C) 2019-2021 Intel Corporation
+ *
+ * Author:
+ *	Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
+ */
+
+#include <linux/cpufeature.h>
+
+#include <asm/cmdline.h>
+#include <asm/cpu.h>
+
+#include "cpu.h"
+
+#undef pr_fmt
+#define pr_fmt(fmt) "tsx: " fmt
+
+enum tsx_ctrl_states tsx_ctrl_state __ro_after_init = TSX_CTRL_NOT_SUPPORTED;
+
+static void tsx_disable(void)
+{
+	u64 tsx;
+
+	rdmsrl(MSR_IA32_TSX_CTRL, tsx);
+
+	/* Force all transactions to immediately abort */
+	tsx |= TSX_CTRL_RTM_DISABLE;
+
+	/*
+	 * Ensure TSX support is not enumerated in CPUID.
+	 * This is visible to userspace and will ensure they
+	 * do not waste resources trying TSX transactions that
+	 * will always abort.
+	 */
+	tsx |= TSX_CTRL_CPUID_CLEAR;
+
+	wrmsrl(MSR_IA32_TSX_CTRL, tsx);
+}
+
+static void tsx_enable(void)
+{
+	u64 tsx;
+
+	rdmsrl(MSR_IA32_TSX_CTRL, tsx);
+
+	/* Enable the RTM feature in the cpu */
+	tsx &= ~TSX_CTRL_RTM_DISABLE;
+
+	/*
+	 * Ensure TSX support is enumerated in CPUID.
+	 * This is visible to userspace and will ensure they
+	 * can enumerate and use the TSX feature.
+	 */
+	tsx &= ~TSX_CTRL_CPUID_CLEAR;
+
+	wrmsrl(MSR_IA32_TSX_CTRL, tsx);
+}
+
+static enum tsx_ctrl_states x86_get_tsx_auto_mode(void)
+{
+	if (boot_cpu_has_bug(X86_BUG_TAA))
+		return TSX_CTRL_DISABLE;
+
+	return TSX_CTRL_ENABLE;
+}
+
+/*
+ * Disabling TSX is not a trivial business.
+ *
+ * First of all, there's a CPUID bit: X86_FEATURE_RTM_ALWAYS_ABORT
+ * which says that TSX is practically disabled (all transactions are
+ * aborted by default). When that bit is set, the kernel unconditionally
+ * disables TSX.
+ *
+ * In order to do that, however, it needs to dance a bit:
+ *
+ * 1. The first method to disable it is through MSR_TSX_FORCE_ABORT and
+ * the MSR is present only when *two* CPUID bits are set:
+ *
+ * - X86_FEATURE_RTM_ALWAYS_ABORT
+ * - X86_FEATURE_TSX_FORCE_ABORT
+ *
+ * 2. The second method is for CPUs which do not have the above-mentioned
+ * MSR: those use a different MSR - MSR_IA32_TSX_CTRL and disable TSX
+ * through that one. Those CPUs can also have the initially mentioned
+ * CPUID bit X86_FEATURE_RTM_ALWAYS_ABORT set and for those the same strategy
+ * applies: TSX gets disabled unconditionally.
+ *
+ * When either of the two methods are present, the kernel disables TSX and
+ * clears the respective RTM and HLE feature flags.
+ *
+ * An additional twist in the whole thing presents late microcode loading
+ * which, when done, may cause for the X86_FEATURE_RTM_ALWAYS_ABORT CPUID
+ * bit to be set after the update.
+ *
+ * A subsequent hotplug operation on any logical CPU except the BSP will
+ * cause for the supported CPUID feature bits to get re-detected and, if
+ * RTM and HLE get cleared all of a sudden, but, userspace did consult
+ * them before the update, then funny explosions will happen. Long story
+ * short: the kernel doesn't modify CPUID feature bits after booting.
+ *
+ * That's why, this function's call in init_intel() doesn't clear the
+ * feature flags.
+ */
+static void tsx_clear_cpuid(void)
+{
+	u64 msr;
+
+	/*
+	 * MSR_TFA_TSX_CPUID_CLEAR bit is only present when both CPUID
+	 * bits RTM_ALWAYS_ABORT and TSX_FORCE_ABORT are present.
+	 */
+	if (boot_cpu_has(X86_FEATURE_RTM_ALWAYS_ABORT) &&
+	    boot_cpu_has(X86_FEATURE_TSX_FORCE_ABORT)) {
+		rdmsrl(MSR_TSX_FORCE_ABORT, msr);
+		msr |= MSR_TFA_TSX_CPUID_CLEAR;
+		wrmsrl(MSR_TSX_FORCE_ABORT, msr);
+	} else if (cpu_feature_enabled(X86_FEATURE_MSR_TSX_CTRL)) {
+		rdmsrl(MSR_IA32_TSX_CTRL, msr);
+		msr |= TSX_CTRL_CPUID_CLEAR;
+		wrmsrl(MSR_IA32_TSX_CTRL, msr);
+	}
+}
+
+/*
+ * Disable TSX development mode
+ *
+ * When the microcode released in Feb 2022 is applied, TSX will be disabled by
+ * default on some processors. MSR 0x122 (TSX_CTRL) and MSR 0x123
+ * (IA32_MCU_OPT_CTRL) can be used to re-enable TSX for development, doing so is
+ * not recommended for production deployments. In particular, applying MD_CLEAR
+ * flows for mitigation of the Intel TSX Asynchronous Abort (TAA) transient
+ * execution attack may not be effective on these processors when Intel TSX is
+ * enabled with updated microcode.
+ */
+static void tsx_dev_mode_disable(void)
+{
+	u64 mcu_opt_ctrl;
+
+	/* Check if RTM_ALLOW exists */
+	if (!boot_cpu_has_bug(X86_BUG_TAA) ||
+	    !cpu_feature_enabled(X86_FEATURE_MSR_TSX_CTRL) ||
+	    !cpu_feature_enabled(X86_FEATURE_SRBDS_CTRL))
+		return;
+
+	rdmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_opt_ctrl);
+
+	if (mcu_opt_ctrl & RTM_ALLOW) {
+		mcu_opt_ctrl &= ~RTM_ALLOW;
+		wrmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_opt_ctrl);
+		setup_force_cpu_cap(X86_FEATURE_RTM_ALWAYS_ABORT);
+	}
+}
+
+void __init tsx_init(void)
+{
+	char arg[5] = {};
+	int ret;
+
+	tsx_dev_mode_disable();
+
+	/*
+	 * Hardware will always abort a TSX transaction when the CPUID bit
+	 * RTM_ALWAYS_ABORT is set. In this case, it is better not to enumerate
+	 * CPUID.RTM and CPUID.HLE bits. Clear them here.
+	 */
+	if (boot_cpu_has(X86_FEATURE_RTM_ALWAYS_ABORT)) {
+		tsx_ctrl_state = TSX_CTRL_RTM_ALWAYS_ABORT;
+		tsx_clear_cpuid();
+		setup_clear_cpu_cap(X86_FEATURE_RTM);
+		setup_clear_cpu_cap(X86_FEATURE_HLE);
+		return;
+	}
+
+	/*
+	 * TSX is controlled via MSR_IA32_TSX_CTRL.  However, support for this
+	 * MSR is enumerated by ARCH_CAP_TSX_MSR bit in MSR_IA32_ARCH_CAPABILITIES.
+	 *
+	 * TSX control (aka MSR_IA32_TSX_CTRL) is only available after a
+	 * microcode update on CPUs that have their MSR_IA32_ARCH_CAPABILITIES
+	 * bit MDS_NO=1. CPUs with MDS_NO=0 are not planned to get
+	 * MSR_IA32_TSX_CTRL support even after a microcode update. Thus,
+	 * tsx= cmdline requests will do nothing on CPUs without
+	 * MSR_IA32_TSX_CTRL support.
+	 */
+	if (x86_read_arch_cap_msr() & ARCH_CAP_TSX_CTRL_MSR) {
+		setup_force_cpu_cap(X86_FEATURE_MSR_TSX_CTRL);
+	} else {
+		tsx_ctrl_state = TSX_CTRL_NOT_SUPPORTED;
+		return;
+	}
+
+	ret = cmdline_find_option(boot_command_line, "tsx", arg, sizeof(arg));
+	if (ret >= 0) {
+		if (!strcmp(arg, "on")) {
+			tsx_ctrl_state = TSX_CTRL_ENABLE;
+		} else if (!strcmp(arg, "off")) {
+			tsx_ctrl_state = TSX_CTRL_DISABLE;
+		} else if (!strcmp(arg, "auto")) {
+			tsx_ctrl_state = x86_get_tsx_auto_mode();
+		} else {
+			tsx_ctrl_state = TSX_CTRL_DISABLE;
+			pr_err("invalid option, defaulting to off\n");
+		}
+	} else {
+		/* tsx= not provided */
+		if (IS_ENABLED(CONFIG_X86_INTEL_TSX_MODE_AUTO))
+			tsx_ctrl_state = x86_get_tsx_auto_mode();
+		else if (IS_ENABLED(CONFIG_X86_INTEL_TSX_MODE_OFF))
+			tsx_ctrl_state = TSX_CTRL_DISABLE;
+		else
+			tsx_ctrl_state = TSX_CTRL_ENABLE;
+	}
+
+	if (tsx_ctrl_state == TSX_CTRL_DISABLE) {
+		tsx_disable();
+
+		/*
+		 * tsx_disable() will change the state of the RTM and HLE CPUID
+		 * bits. Clear them here since they are now expected to be not
+		 * set.
+		 */
+		setup_clear_cpu_cap(X86_FEATURE_RTM);
+		setup_clear_cpu_cap(X86_FEATURE_HLE);
+	} else if (tsx_ctrl_state == TSX_CTRL_ENABLE) {
+
+		/*
+		 * HW defaults TSX to be enabled at bootup.
+		 * We may still need the TSX enable support
+		 * during init for special cases like
+		 * kexec after TSX is disabled.
+		 */
+		tsx_enable();
+
+		/*
+		 * tsx_enable() will change the state of the RTM and HLE CPUID
+		 * bits. Force them here since they are now expected to be set.
+		 */
+		setup_force_cpu_cap(X86_FEATURE_RTM);
+		setup_force_cpu_cap(X86_FEATURE_HLE);
+	}
+}
+
+void tsx_ap_init(void)
+{
+	tsx_dev_mode_disable();
+
+	if (tsx_ctrl_state == TSX_CTRL_ENABLE)
+		tsx_enable();
+	else if (tsx_ctrl_state == TSX_CTRL_DISABLE)
+		tsx_disable();
+	else if (tsx_ctrl_state == TSX_CTRL_RTM_ALWAYS_ABORT)
+		/* See comment over that function for more details. */
+		tsx_clear_cpuid();
+}
diff --git a/arch/x86/kernel/cpu/umc.c b/arch/x86/kernel/cpu/umc.c
new file mode 100644
index 0000000000..65a58a390f
--- /dev/null
+++ b/arch/x86/kernel/cpu/umc.c
@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <asm/processor.h>
+#include "cpu.h"
+
+/*
+ * UMC chips appear to be only either 386 or 486,
+ * so no special init takes place.
+ */
+
+static const struct cpu_dev umc_cpu_dev = {
+	.c_vendor	= "UMC",
+	.c_ident	= { "UMC UMC UMC" },
+	.legacy_models	= {
+		{ .family = 4, .model_names =
+		  {
+			  [1] = "U5D",
+			  [2] = "U5S",
+		  }
+		},
+	},
+	.c_x86_vendor	= X86_VENDOR_UMC,
+};
+
+cpu_dev_register(umc_cpu_dev);
+
diff --git a/arch/x86/kernel/cpu/umwait.c b/arch/x86/kernel/cpu/umwait.c
new file mode 100644
index 0000000000..2293efd6ff
--- /dev/null
+++ b/arch/x86/kernel/cpu/umwait.c
@@ -0,0 +1,242 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/syscore_ops.h>
+#include <linux/suspend.h>
+#include <linux/cpu.h>
+
+#include <asm/msr.h>
+#include <asm/mwait.h>
+
+#define UMWAIT_C02_ENABLE	0
+
+#define UMWAIT_CTRL_VAL(max_time, c02_disable)				\
+	(((max_time) & MSR_IA32_UMWAIT_CONTROL_TIME_MASK) |		\
+	((c02_disable) & MSR_IA32_UMWAIT_CONTROL_C02_DISABLE))
+
+/*
+ * Cache IA32_UMWAIT_CONTROL MSR. This is a systemwide control. By default,
+ * umwait max time is 100000 in TSC-quanta and C0.2 is enabled
+ */
+static u32 umwait_control_cached = UMWAIT_CTRL_VAL(100000, UMWAIT_C02_ENABLE);
+
+/*
+ * Cache the original IA32_UMWAIT_CONTROL MSR value which is configured by
+ * hardware or BIOS before kernel boot.
+ */
+static u32 orig_umwait_control_cached __ro_after_init;
+
+/*
+ * Serialize access to umwait_control_cached and IA32_UMWAIT_CONTROL MSR in
+ * the sysfs write functions.
+ */
+static DEFINE_MUTEX(umwait_lock);
+
+static void umwait_update_control_msr(void * unused)
+{
+	lockdep_assert_irqs_disabled();
+	wrmsr(MSR_IA32_UMWAIT_CONTROL, READ_ONCE(umwait_control_cached), 0);
+}
+
+/*
+ * The CPU hotplug callback sets the control MSR to the global control
+ * value.
+ *
+ * Disable interrupts so the read of umwait_control_cached and the WRMSR
+ * are protected against a concurrent sysfs write. Otherwise the sysfs
+ * write could update the cached value after it had been read on this CPU
+ * and issue the IPI before the old value had been written. The IPI would
+ * interrupt, write the new value and after return from IPI the previous
+ * value would be written by this CPU.
+ *
+ * With interrupts disabled the upcoming CPU either sees the new control
+ * value or the IPI is updating this CPU to the new control value after
+ * interrupts have been reenabled.
+ */
+static int umwait_cpu_online(unsigned int cpu)
+{
+	local_irq_disable();
+	umwait_update_control_msr(NULL);
+	local_irq_enable();
+	return 0;
+}
+
+/*
+ * The CPU hotplug callback sets the control MSR to the original control
+ * value.
+ */
+static int umwait_cpu_offline(unsigned int cpu)
+{
+	/*
+	 * This code is protected by the CPU hotplug already and
+	 * orig_umwait_control_cached is never changed after it caches
+	 * the original control MSR value in umwait_init(). So there
+	 * is no race condition here.
+	 */
+	wrmsr(MSR_IA32_UMWAIT_CONTROL, orig_umwait_control_cached, 0);
+
+	return 0;
+}
+
+/*
+ * On resume, restore IA32_UMWAIT_CONTROL MSR on the boot processor which
+ * is the only active CPU at this time. The MSR is set up on the APs via the
+ * CPU hotplug callback.
+ *
+ * This function is invoked on resume from suspend and hibernation. On
+ * resume from suspend the restore should be not required, but we neither
+ * trust the firmware nor does it matter if the same value is written
+ * again.
+ */
+static void umwait_syscore_resume(void)
+{
+	umwait_update_control_msr(NULL);
+}
+
+static struct syscore_ops umwait_syscore_ops = {
+	.resume	= umwait_syscore_resume,
+};
+
+/* sysfs interface */
+
+/*
+ * When bit 0 in IA32_UMWAIT_CONTROL MSR is 1, C0.2 is disabled.
+ * Otherwise, C0.2 is enabled.
+ */
+static inline bool umwait_ctrl_c02_enabled(u32 ctrl)
+{
+	return !(ctrl & MSR_IA32_UMWAIT_CONTROL_C02_DISABLE);
+}
+
+static inline u32 umwait_ctrl_max_time(u32 ctrl)
+{
+	return ctrl & MSR_IA32_UMWAIT_CONTROL_TIME_MASK;
+}
+
+static inline void umwait_update_control(u32 maxtime, bool c02_enable)
+{
+	u32 ctrl = maxtime & MSR_IA32_UMWAIT_CONTROL_TIME_MASK;
+
+	if (!c02_enable)
+		ctrl |= MSR_IA32_UMWAIT_CONTROL_C02_DISABLE;
+
+	WRITE_ONCE(umwait_control_cached, ctrl);
+	/* Propagate to all CPUs */
+	on_each_cpu(umwait_update_control_msr, NULL, 1);
+}
+
+static ssize_t
+enable_c02_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	u32 ctrl = READ_ONCE(umwait_control_cached);
+
+	return sprintf(buf, "%d\n", umwait_ctrl_c02_enabled(ctrl));
+}
+
+static ssize_t enable_c02_store(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t count)
+{
+	bool c02_enable;
+	u32 ctrl;
+	int ret;
+
+	ret = kstrtobool(buf, &c02_enable);
+	if (ret)
+		return ret;
+
+	mutex_lock(&umwait_lock);
+
+	ctrl = READ_ONCE(umwait_control_cached);
+	if (c02_enable != umwait_ctrl_c02_enabled(ctrl))
+		umwait_update_control(ctrl, c02_enable);
+
+	mutex_unlock(&umwait_lock);
+
+	return count;
+}
+static DEVICE_ATTR_RW(enable_c02);
+
+static ssize_t
+max_time_show(struct device *kobj, struct device_attribute *attr, char *buf)
+{
+	u32 ctrl = READ_ONCE(umwait_control_cached);
+
+	return sprintf(buf, "%u\n", umwait_ctrl_max_time(ctrl));
+}
+
+static ssize_t max_time_store(struct device *kobj,
+			      struct device_attribute *attr,
+			      const char *buf, size_t count)
+{
+	u32 max_time, ctrl;
+	int ret;
+
+	ret = kstrtou32(buf, 0, &max_time);
+	if (ret)
+		return ret;
+
+	/* bits[1:0] must be zero */
+	if (max_time & ~MSR_IA32_UMWAIT_CONTROL_TIME_MASK)
+		return -EINVAL;
+
+	mutex_lock(&umwait_lock);
+
+	ctrl = READ_ONCE(umwait_control_cached);
+	if (max_time != umwait_ctrl_max_time(ctrl))
+		umwait_update_control(max_time, umwait_ctrl_c02_enabled(ctrl));
+
+	mutex_unlock(&umwait_lock);
+
+	return count;
+}
+static DEVICE_ATTR_RW(max_time);
+
+static struct attribute *umwait_attrs[] = {
+	&dev_attr_enable_c02.attr,
+	&dev_attr_max_time.attr,
+	NULL
+};
+
+static struct attribute_group umwait_attr_group = {
+	.attrs = umwait_attrs,
+	.name = "umwait_control",
+};
+
+static int __init umwait_init(void)
+{
+	struct device *dev;
+	int ret;
+
+	if (!boot_cpu_has(X86_FEATURE_WAITPKG))
+		return -ENODEV;
+
+	/*
+	 * Cache the original control MSR value before the control MSR is
+	 * changed. This is the only place where orig_umwait_control_cached
+	 * is modified.
+	 */
+	rdmsrl(MSR_IA32_UMWAIT_CONTROL, orig_umwait_control_cached);
+
+	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "umwait:online",
+				umwait_cpu_online, umwait_cpu_offline);
+	if (ret < 0) {
+		/*
+		 * On failure, the control MSR on all CPUs has the
+		 * original control value.
+		 */
+		return ret;
+	}
+
+	register_syscore_ops(&umwait_syscore_ops);
+
+	/*
+	 * Add umwait control interface. Ignore failure, so at least the
+	 * default values are set up in case the machine manages to boot.
+	 */
+	dev = bus_get_dev_root(&cpu_subsys);
+	if (dev) {
+		ret = sysfs_create_group(&dev->kobj, &umwait_attr_group);
+		put_device(dev);
+	}
+	return ret;
+}
+device_initcall(umwait_init);
diff --git a/arch/x86/kernel/cpu/vmware.c b/arch/x86/kernel/cpu/vmware.c
new file mode 100644
index 0000000000..11f83d0792
--- /dev/null
+++ b/arch/x86/kernel/cpu/vmware.c
@@ -0,0 +1,528 @@
+/*
+ * VMware Detection code.
+ *
+ * Copyright (C) 2008, VMware, Inc.
+ * Author : Alok N Kataria <akataria@vmware.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <linux/dmi.h>
+#include <linux/init.h>
+#include <linux/export.h>
+#include <linux/clocksource.h>
+#include <linux/cpu.h>
+#include <linux/reboot.h>
+#include <linux/static_call.h>
+#include <asm/div64.h>
+#include <asm/x86_init.h>
+#include <asm/hypervisor.h>
+#include <asm/timer.h>
+#include <asm/apic.h>
+#include <asm/vmware.h>
+#include <asm/svm.h>
+
+#undef pr_fmt
+#define pr_fmt(fmt)	"vmware: " fmt
+
+#define CPUID_VMWARE_INFO_LEAF               0x40000000
+#define CPUID_VMWARE_FEATURES_LEAF           0x40000010
+#define CPUID_VMWARE_FEATURES_ECX_VMMCALL    BIT(0)
+#define CPUID_VMWARE_FEATURES_ECX_VMCALL     BIT(1)
+
+#define VMWARE_HYPERVISOR_MAGIC	0x564D5868
+
+#define VMWARE_CMD_GETVERSION    10
+#define VMWARE_CMD_GETHZ         45
+#define VMWARE_CMD_GETVCPU_INFO  68
+#define VMWARE_CMD_LEGACY_X2APIC  3
+#define VMWARE_CMD_VCPU_RESERVED 31
+#define VMWARE_CMD_STEALCLOCK    91
+
+#define STEALCLOCK_NOT_AVAILABLE (-1)
+#define STEALCLOCK_DISABLED        0
+#define STEALCLOCK_ENABLED         1
+
+#define VMWARE_PORT(cmd, eax, ebx, ecx, edx)				\
+	__asm__("inl (%%dx), %%eax" :					\
+		"=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) :		\
+		"a"(VMWARE_HYPERVISOR_MAGIC),				\
+		"c"(VMWARE_CMD_##cmd),					\
+		"d"(VMWARE_HYPERVISOR_PORT), "b"(UINT_MAX) :		\
+		"memory")
+
+#define VMWARE_VMCALL(cmd, eax, ebx, ecx, edx)				\
+	__asm__("vmcall" :						\
+		"=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) :		\
+		"a"(VMWARE_HYPERVISOR_MAGIC),				\
+		"c"(VMWARE_CMD_##cmd),					\
+		"d"(0), "b"(UINT_MAX) :					\
+		"memory")
+
+#define VMWARE_VMMCALL(cmd, eax, ebx, ecx, edx)                         \
+	__asm__("vmmcall" :						\
+		"=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) :		\
+		"a"(VMWARE_HYPERVISOR_MAGIC),				\
+		"c"(VMWARE_CMD_##cmd),					\
+		"d"(0), "b"(UINT_MAX) :					\
+		"memory")
+
+#define VMWARE_CMD(cmd, eax, ebx, ecx, edx) do {		\
+	switch (vmware_hypercall_mode) {			\
+	case CPUID_VMWARE_FEATURES_ECX_VMCALL:			\
+		VMWARE_VMCALL(cmd, eax, ebx, ecx, edx);		\
+		break;						\
+	case CPUID_VMWARE_FEATURES_ECX_VMMCALL:			\
+		VMWARE_VMMCALL(cmd, eax, ebx, ecx, edx);	\
+		break;						\
+	default:						\
+		VMWARE_PORT(cmd, eax, ebx, ecx, edx);		\
+		break;						\
+	}							\
+	} while (0)
+
+struct vmware_steal_time {
+	union {
+		uint64_t clock;	/* stolen time counter in units of vtsc */
+		struct {
+			/* only for little-endian */
+			uint32_t clock_low;
+			uint32_t clock_high;
+		};
+	};
+	uint64_t reserved[7];
+};
+
+static unsigned long vmware_tsc_khz __ro_after_init;
+static u8 vmware_hypercall_mode     __ro_after_init;
+
+static inline int __vmware_platform(void)
+{
+	uint32_t eax, ebx, ecx, edx;
+	VMWARE_CMD(GETVERSION, eax, ebx, ecx, edx);
+	return eax != (uint32_t)-1 && ebx == VMWARE_HYPERVISOR_MAGIC;
+}
+
+static unsigned long vmware_get_tsc_khz(void)
+{
+	return vmware_tsc_khz;
+}
+
+#ifdef CONFIG_PARAVIRT
+static struct cyc2ns_data vmware_cyc2ns __ro_after_init;
+static bool vmw_sched_clock __initdata = true;
+static DEFINE_PER_CPU_DECRYPTED(struct vmware_steal_time, vmw_steal_time) __aligned(64);
+static bool has_steal_clock;
+static bool steal_acc __initdata = true; /* steal time accounting */
+
+static __init int setup_vmw_sched_clock(char *s)
+{
+	vmw_sched_clock = false;
+	return 0;
+}
+early_param("no-vmw-sched-clock", setup_vmw_sched_clock);
+
+static __init int parse_no_stealacc(char *arg)
+{
+	steal_acc = false;
+	return 0;
+}
+early_param("no-steal-acc", parse_no_stealacc);
+
+static noinstr u64 vmware_sched_clock(void)
+{
+	unsigned long long ns;
+
+	ns = mul_u64_u32_shr(rdtsc(), vmware_cyc2ns.cyc2ns_mul,
+			     vmware_cyc2ns.cyc2ns_shift);
+	ns -= vmware_cyc2ns.cyc2ns_offset;
+	return ns;
+}
+
+static void __init vmware_cyc2ns_setup(void)
+{
+	struct cyc2ns_data *d = &vmware_cyc2ns;
+	unsigned long long tsc_now = rdtsc();
+
+	clocks_calc_mult_shift(&d->cyc2ns_mul, &d->cyc2ns_shift,
+			       vmware_tsc_khz, NSEC_PER_MSEC, 0);
+	d->cyc2ns_offset = mul_u64_u32_shr(tsc_now, d->cyc2ns_mul,
+					   d->cyc2ns_shift);
+
+	pr_info("using clock offset of %llu ns\n", d->cyc2ns_offset);
+}
+
+static int vmware_cmd_stealclock(uint32_t arg1, uint32_t arg2)
+{
+	uint32_t result, info;
+
+	asm volatile (VMWARE_HYPERCALL :
+		"=a"(result),
+		"=c"(info) :
+		"a"(VMWARE_HYPERVISOR_MAGIC),
+		"b"(0),
+		"c"(VMWARE_CMD_STEALCLOCK),
+		"d"(0),
+		"S"(arg1),
+		"D"(arg2) :
+		"memory");
+	return result;
+}
+
+static bool stealclock_enable(phys_addr_t pa)
+{
+	return vmware_cmd_stealclock(upper_32_bits(pa),
+				     lower_32_bits(pa)) == STEALCLOCK_ENABLED;
+}
+
+static int __stealclock_disable(void)
+{
+	return vmware_cmd_stealclock(0, 1);
+}
+
+static void stealclock_disable(void)
+{
+	__stealclock_disable();
+}
+
+static bool vmware_is_stealclock_available(void)
+{
+	return __stealclock_disable() != STEALCLOCK_NOT_AVAILABLE;
+}
+
+/**
+ * vmware_steal_clock() - read the per-cpu steal clock
+ * @cpu:            the cpu number whose steal clock we want to read
+ *
+ * The function reads the steal clock if we are on a 64-bit system, otherwise
+ * reads it in parts, checking that the high part didn't change in the
+ * meantime.
+ *
+ * Return:
+ *      The steal clock reading in ns.
+ */
+static uint64_t vmware_steal_clock(int cpu)
+{
+	struct vmware_steal_time *steal = &per_cpu(vmw_steal_time, cpu);
+	uint64_t clock;
+
+	if (IS_ENABLED(CONFIG_64BIT))
+		clock = READ_ONCE(steal->clock);
+	else {
+		uint32_t initial_high, low, high;
+
+		do {
+			initial_high = READ_ONCE(steal->clock_high);
+			/* Do not reorder initial_high and high readings */
+			virt_rmb();
+			low = READ_ONCE(steal->clock_low);
+			/* Keep low reading in between */
+			virt_rmb();
+			high = READ_ONCE(steal->clock_high);
+		} while (initial_high != high);
+
+		clock = ((uint64_t)high << 32) | low;
+	}
+
+	return mul_u64_u32_shr(clock, vmware_cyc2ns.cyc2ns_mul,
+			     vmware_cyc2ns.cyc2ns_shift);
+}
+
+static void vmware_register_steal_time(void)
+{
+	int cpu = smp_processor_id();
+	struct vmware_steal_time *st = &per_cpu(vmw_steal_time, cpu);
+
+	if (!has_steal_clock)
+		return;
+
+	if (!stealclock_enable(slow_virt_to_phys(st))) {
+		has_steal_clock = false;
+		return;
+	}
+
+	pr_info("vmware-stealtime: cpu %d, pa %llx\n",
+		cpu, (unsigned long long) slow_virt_to_phys(st));
+}
+
+static void vmware_disable_steal_time(void)
+{
+	if (!has_steal_clock)
+		return;
+
+	stealclock_disable();
+}
+
+static void vmware_guest_cpu_init(void)
+{
+	if (has_steal_clock)
+		vmware_register_steal_time();
+}
+
+static void vmware_pv_guest_cpu_reboot(void *unused)
+{
+	vmware_disable_steal_time();
+}
+
+static int vmware_pv_reboot_notify(struct notifier_block *nb,
+				unsigned long code, void *unused)
+{
+	if (code == SYS_RESTART)
+		on_each_cpu(vmware_pv_guest_cpu_reboot, NULL, 1);
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block vmware_pv_reboot_nb = {
+	.notifier_call = vmware_pv_reboot_notify,
+};
+
+#ifdef CONFIG_SMP
+static void __init vmware_smp_prepare_boot_cpu(void)
+{
+	vmware_guest_cpu_init();
+	native_smp_prepare_boot_cpu();
+}
+
+static int vmware_cpu_online(unsigned int cpu)
+{
+	local_irq_disable();
+	vmware_guest_cpu_init();
+	local_irq_enable();
+	return 0;
+}
+
+static int vmware_cpu_down_prepare(unsigned int cpu)
+{
+	local_irq_disable();
+	vmware_disable_steal_time();
+	local_irq_enable();
+	return 0;
+}
+#endif
+
+static __init int activate_jump_labels(void)
+{
+	if (has_steal_clock) {
+		static_key_slow_inc(&paravirt_steal_enabled);
+		if (steal_acc)
+			static_key_slow_inc(&paravirt_steal_rq_enabled);
+	}
+
+	return 0;
+}
+arch_initcall(activate_jump_labels);
+
+static void __init vmware_paravirt_ops_setup(void)
+{
+	pv_info.name = "VMware hypervisor";
+	pv_ops.cpu.io_delay = paravirt_nop;
+
+	if (vmware_tsc_khz == 0)
+		return;
+
+	vmware_cyc2ns_setup();
+
+	if (vmw_sched_clock)
+		paravirt_set_sched_clock(vmware_sched_clock);
+
+	if (vmware_is_stealclock_available()) {
+		has_steal_clock = true;
+		static_call_update(pv_steal_clock, vmware_steal_clock);
+
+		/* We use reboot notifier only to disable steal clock */
+		register_reboot_notifier(&vmware_pv_reboot_nb);
+
+#ifdef CONFIG_SMP
+		smp_ops.smp_prepare_boot_cpu =
+			vmware_smp_prepare_boot_cpu;
+		if (cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
+					      "x86/vmware:online",
+					      vmware_cpu_online,
+					      vmware_cpu_down_prepare) < 0)
+			pr_err("vmware_guest: Failed to install cpu hotplug callbacks\n");
+#else
+		vmware_guest_cpu_init();
+#endif
+	}
+}
+#else
+#define vmware_paravirt_ops_setup() do {} while (0)
+#endif
+
+/*
+ * VMware hypervisor takes care of exporting a reliable TSC to the guest.
+ * Still, due to timing difference when running on virtual cpus, the TSC can
+ * be marked as unstable in some cases. For example, the TSC sync check at
+ * bootup can fail due to a marginal offset between vcpus' TSCs (though the
+ * TSCs do not drift from each other).  Also, the ACPI PM timer clocksource
+ * is not suitable as a watchdog when running on a hypervisor because the
+ * kernel may miss a wrap of the counter if the vcpu is descheduled for a
+ * long time. To skip these checks at runtime we set these capability bits,
+ * so that the kernel could just trust the hypervisor with providing a
+ * reliable virtual TSC that is suitable for timekeeping.
+ */
+static void __init vmware_set_capabilities(void)
+{
+	setup_force_cpu_cap(X86_FEATURE_CONSTANT_TSC);
+	setup_force_cpu_cap(X86_FEATURE_TSC_RELIABLE);
+	if (vmware_tsc_khz)
+		setup_force_cpu_cap(X86_FEATURE_TSC_KNOWN_FREQ);
+	if (vmware_hypercall_mode == CPUID_VMWARE_FEATURES_ECX_VMCALL)
+		setup_force_cpu_cap(X86_FEATURE_VMCALL);
+	else if (vmware_hypercall_mode == CPUID_VMWARE_FEATURES_ECX_VMMCALL)
+		setup_force_cpu_cap(X86_FEATURE_VMW_VMMCALL);
+}
+
+static void __init vmware_platform_setup(void)
+{
+	uint32_t eax, ebx, ecx, edx;
+	uint64_t lpj, tsc_khz;
+
+	VMWARE_CMD(GETHZ, eax, ebx, ecx, edx);
+
+	if (ebx != UINT_MAX) {
+		lpj = tsc_khz = eax | (((uint64_t)ebx) << 32);
+		do_div(tsc_khz, 1000);
+		WARN_ON(tsc_khz >> 32);
+		pr_info("TSC freq read from hypervisor : %lu.%03lu MHz\n",
+			(unsigned long) tsc_khz / 1000,
+			(unsigned long) tsc_khz % 1000);
+
+		if (!preset_lpj) {
+			do_div(lpj, HZ);
+			preset_lpj = lpj;
+		}
+
+		vmware_tsc_khz = tsc_khz;
+		x86_platform.calibrate_tsc = vmware_get_tsc_khz;
+		x86_platform.calibrate_cpu = vmware_get_tsc_khz;
+
+#ifdef CONFIG_X86_LOCAL_APIC
+		/* Skip lapic calibration since we know the bus frequency. */
+		lapic_timer_period = ecx / HZ;
+		pr_info("Host bus clock speed read from hypervisor : %u Hz\n",
+			ecx);
+#endif
+	} else {
+		pr_warn("Failed to get TSC freq from the hypervisor\n");
+	}
+
+	vmware_paravirt_ops_setup();
+
+#ifdef CONFIG_X86_IO_APIC
+	no_timer_check = 1;
+#endif
+
+	vmware_set_capabilities();
+}
+
+static u8 __init vmware_select_hypercall(void)
+{
+	int eax, ebx, ecx, edx;
+
+	cpuid(CPUID_VMWARE_FEATURES_LEAF, &eax, &ebx, &ecx, &edx);
+	return (ecx & (CPUID_VMWARE_FEATURES_ECX_VMMCALL |
+		       CPUID_VMWARE_FEATURES_ECX_VMCALL));
+}
+
+/*
+ * While checking the dmi string information, just checking the product
+ * serial key should be enough, as this will always have a VMware
+ * specific string when running under VMware hypervisor.
+ * If !boot_cpu_has(X86_FEATURE_HYPERVISOR), vmware_hypercall_mode
+ * intentionally defaults to 0.
+ */
+static uint32_t __init vmware_platform(void)
+{
+	if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
+		unsigned int eax;
+		unsigned int hyper_vendor_id[3];
+
+		cpuid(CPUID_VMWARE_INFO_LEAF, &eax, &hyper_vendor_id[0],
+		      &hyper_vendor_id[1], &hyper_vendor_id[2]);
+		if (!memcmp(hyper_vendor_id, "VMwareVMware", 12)) {
+			if (eax >= CPUID_VMWARE_FEATURES_LEAF)
+				vmware_hypercall_mode =
+					vmware_select_hypercall();
+
+			pr_info("hypercall mode: 0x%02x\n",
+				(unsigned int) vmware_hypercall_mode);
+
+			return CPUID_VMWARE_INFO_LEAF;
+		}
+	} else if (dmi_available && dmi_name_in_serial("VMware") &&
+		   __vmware_platform())
+		return 1;
+
+	return 0;
+}
+
+/* Checks if hypervisor supports x2apic without VT-D interrupt remapping. */
+static bool __init vmware_legacy_x2apic_available(void)
+{
+	uint32_t eax, ebx, ecx, edx;
+	VMWARE_CMD(GETVCPU_INFO, eax, ebx, ecx, edx);
+	return !(eax & BIT(VMWARE_CMD_VCPU_RESERVED)) &&
+		(eax & BIT(VMWARE_CMD_LEGACY_X2APIC));
+}
+
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+static void vmware_sev_es_hcall_prepare(struct ghcb *ghcb,
+					struct pt_regs *regs)
+{
+	/* Copy VMWARE specific Hypercall parameters to the GHCB */
+	ghcb_set_rip(ghcb, regs->ip);
+	ghcb_set_rbx(ghcb, regs->bx);
+	ghcb_set_rcx(ghcb, regs->cx);
+	ghcb_set_rdx(ghcb, regs->dx);
+	ghcb_set_rsi(ghcb, regs->si);
+	ghcb_set_rdi(ghcb, regs->di);
+	ghcb_set_rbp(ghcb, regs->bp);
+}
+
+static bool vmware_sev_es_hcall_finish(struct ghcb *ghcb, struct pt_regs *regs)
+{
+	if (!(ghcb_rbx_is_valid(ghcb) &&
+	      ghcb_rcx_is_valid(ghcb) &&
+	      ghcb_rdx_is_valid(ghcb) &&
+	      ghcb_rsi_is_valid(ghcb) &&
+	      ghcb_rdi_is_valid(ghcb) &&
+	      ghcb_rbp_is_valid(ghcb)))
+		return false;
+
+	regs->bx = ghcb_get_rbx(ghcb);
+	regs->cx = ghcb_get_rcx(ghcb);
+	regs->dx = ghcb_get_rdx(ghcb);
+	regs->si = ghcb_get_rsi(ghcb);
+	regs->di = ghcb_get_rdi(ghcb);
+	regs->bp = ghcb_get_rbp(ghcb);
+
+	return true;
+}
+#endif
+
+const __initconst struct hypervisor_x86 x86_hyper_vmware = {
+	.name				= "VMware",
+	.detect				= vmware_platform,
+	.type				= X86_HYPER_VMWARE,
+	.init.init_platform		= vmware_platform_setup,
+	.init.x2apic_available		= vmware_legacy_x2apic_available,
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+	.runtime.sev_es_hcall_prepare	= vmware_sev_es_hcall_prepare,
+	.runtime.sev_es_hcall_finish	= vmware_sev_es_hcall_finish,
+#endif
+};
diff --git a/arch/x86/kernel/cpu/vortex.c b/arch/x86/kernel/cpu/vortex.c
new file mode 100644
index 0000000000..e2685470ba
--- /dev/null
+++ b/arch/x86/kernel/cpu/vortex.c
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <asm/processor.h>
+#include "cpu.h"
+
+/*
+ * No special init required for Vortex processors.
+ */
+
+static const struct cpu_dev vortex_cpu_dev = {
+	.c_vendor	= "Vortex",
+	.c_ident	= { "Vortex86 SoC" },
+	.legacy_models	= {
+		{
+			.family = 5,
+			.model_names = {
+				[2] = "Vortex86DX",
+				[8] = "Vortex86MX",
+			},
+		},
+		{
+			.family = 6,
+			.model_names = {
+				/*
+				 * Both the Vortex86EX and the Vortex86EX2
+				 * have the same family and model id.
+				 *
+				 * However, the -EX2 supports the product name
+				 * CPUID call, so this name will only be used
+				 * for the -EX, which does not.
+				 */
+				[0] = "Vortex86EX",
+			},
+		},
+	},
+	.c_x86_vendor	= X86_VENDOR_VORTEX,
+};
+
+cpu_dev_register(vortex_cpu_dev);
diff --git a/arch/x86/kernel/cpu/zhaoxin.c b/arch/x86/kernel/cpu/zhaoxin.c
new file mode 100644
index 0000000000..05fa4ef634
--- /dev/null
+++ b/arch/x86/kernel/cpu/zhaoxin.c
@@ -0,0 +1,133 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/sched.h>
+#include <linux/sched/clock.h>
+
+#include <asm/cpu.h>
+#include <asm/cpufeature.h>
+
+#include "cpu.h"
+
+#define MSR_ZHAOXIN_FCR57 0x00001257
+
+#define ACE_PRESENT	(1 << 6)
+#define ACE_ENABLED	(1 << 7)
+#define ACE_FCR		(1 << 7)	/* MSR_ZHAOXIN_FCR */
+
+#define RNG_PRESENT	(1 << 2)
+#define RNG_ENABLED	(1 << 3)
+#define RNG_ENABLE	(1 << 8)	/* MSR_ZHAOXIN_RNG */
+
+static void init_zhaoxin_cap(struct cpuinfo_x86 *c)
+{
+	u32  lo, hi;
+
+	/* Test for Extended Feature Flags presence */
+	if (cpuid_eax(0xC0000000) >= 0xC0000001) {
+		u32 tmp = cpuid_edx(0xC0000001);
+
+		/* Enable ACE unit, if present and disabled */
+		if ((tmp & (ACE_PRESENT | ACE_ENABLED)) == ACE_PRESENT) {
+			rdmsr(MSR_ZHAOXIN_FCR57, lo, hi);
+			/* Enable ACE unit */
+			lo |= ACE_FCR;
+			wrmsr(MSR_ZHAOXIN_FCR57, lo, hi);
+			pr_info("CPU: Enabled ACE h/w crypto\n");
+		}
+
+		/* Enable RNG unit, if present and disabled */
+		if ((tmp & (RNG_PRESENT | RNG_ENABLED)) == RNG_PRESENT) {
+			rdmsr(MSR_ZHAOXIN_FCR57, lo, hi);
+			/* Enable RNG unit */
+			lo |= RNG_ENABLE;
+			wrmsr(MSR_ZHAOXIN_FCR57, lo, hi);
+			pr_info("CPU: Enabled h/w RNG\n");
+		}
+
+		/*
+		 * Store Extended Feature Flags as word 5 of the CPU
+		 * capability bit array
+		 */
+		c->x86_capability[CPUID_C000_0001_EDX] = cpuid_edx(0xC0000001);
+	}
+
+	if (c->x86 >= 0x6)
+		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
+}
+
+static void early_init_zhaoxin(struct cpuinfo_x86 *c)
+{
+	if (c->x86 >= 0x6)
+		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
+#ifdef CONFIG_X86_64
+	set_cpu_cap(c, X86_FEATURE_SYSENTER32);
+#endif
+	if (c->x86_power & (1 << 8)) {
+		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
+		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
+	}
+
+	if (c->cpuid_level >= 0x00000001) {
+		u32 eax, ebx, ecx, edx;
+
+		cpuid(0x00000001, &eax, &ebx, &ecx, &edx);
+		/*
+		 * If HTT (EDX[28]) is set EBX[16:23] contain the number of
+		 * apicids which are reserved per package. Store the resulting
+		 * shift value for the package management code.
+		 */
+		if (edx & (1U << 28))
+			c->x86_coreid_bits = get_count_order((ebx >> 16) & 0xff);
+	}
+
+}
+
+static void init_zhaoxin(struct cpuinfo_x86 *c)
+{
+	early_init_zhaoxin(c);
+	init_intel_cacheinfo(c);
+	detect_num_cpu_cores(c);
+#ifdef CONFIG_X86_32
+	detect_ht(c);
+#endif
+
+	if (c->cpuid_level > 9) {
+		unsigned int eax = cpuid_eax(10);
+
+		/*
+		 * Check for version and the number of counters
+		 * Version(eax[7:0]) can't be 0;
+		 * Counters(eax[15:8]) should be greater than 1;
+		 */
+		if ((eax & 0xff) && (((eax >> 8) & 0xff) > 1))
+			set_cpu_cap(c, X86_FEATURE_ARCH_PERFMON);
+	}
+
+	if (c->x86 >= 0x6)
+		init_zhaoxin_cap(c);
+#ifdef CONFIG_X86_64
+	set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
+#endif
+
+	init_ia32_feat_ctl(c);
+}
+
+#ifdef CONFIG_X86_32
+static unsigned int
+zhaoxin_size_cache(struct cpuinfo_x86 *c, unsigned int size)
+{
+	return size;
+}
+#endif
+
+static const struct cpu_dev zhaoxin_cpu_dev = {
+	.c_vendor	= "zhaoxin",
+	.c_ident	= { "  Shanghai  " },
+	.c_early_init	= early_init_zhaoxin,
+	.c_init		= init_zhaoxin,
+#ifdef CONFIG_X86_32
+	.legacy_cache_size = zhaoxin_size_cache,
+#endif
+	.c_x86_vendor	= X86_VENDOR_ZHAOXIN,
+};
+
+cpu_dev_register(zhaoxin_cpu_dev);