Adding upstream version 6.6.15.upstream/6.6.15

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

1 files changed, 941 insertions, 0 deletions

diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
new file mode 100644
index 0000000000..dc8e8e907c
--- /dev/null
+++ b/arch/x86/kvm/pmu.c
@@ -0,0 +1,941 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Kernel-based Virtual Machine -- Performance Monitoring Unit support
+ *
+ * Copyright 2015 Red Hat, Inc. and/or its affiliates.
+ *
+ * Authors:
+ *   Avi Kivity   <avi@redhat.com>
+ *   Gleb Natapov <gleb@redhat.com>
+ *   Wei Huang    <wei@redhat.com>
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/kvm_host.h>
+#include <linux/perf_event.h>
+#include <linux/bsearch.h>
+#include <linux/sort.h>
+#include <asm/perf_event.h>
+#include <asm/cpu_device_id.h>
+#include "x86.h"
+#include "cpuid.h"
+#include "lapic.h"
+#include "pmu.h"
+
+/* This is enough to filter the vast majority of currently defined events. */
+#define KVM_PMU_EVENT_FILTER_MAX_EVENTS 300
+
+struct x86_pmu_capability __read_mostly kvm_pmu_cap;
+EXPORT_SYMBOL_GPL(kvm_pmu_cap);
+
+/* Precise Distribution of Instructions Retired (PDIR) */
+static const struct x86_cpu_id vmx_pebs_pdir_cpu[] = {
+	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_D, NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_X, NULL),
+	/* Instruction-Accurate PDIR (PDIR++) */
+	X86_MATCH_INTEL_FAM6_MODEL(SAPPHIRERAPIDS_X, NULL),
+	{}
+};
+
+/* Precise Distribution (PDist) */
+static const struct x86_cpu_id vmx_pebs_pdist_cpu[] = {
+	X86_MATCH_INTEL_FAM6_MODEL(SAPPHIRERAPIDS_X, NULL),
+	{}
+};
+
+/* NOTE:
+ * - Each perf counter is defined as "struct kvm_pmc";
+ * - There are two types of perf counters: general purpose (gp) and fixed.
+ *   gp counters are stored in gp_counters[] and fixed counters are stored
+ *   in fixed_counters[] respectively. Both of them are part of "struct
+ *   kvm_pmu";
+ * - pmu.c understands the difference between gp counters and fixed counters.
+ *   However AMD doesn't support fixed-counters;
+ * - There are three types of index to access perf counters (PMC):
+ *     1. MSR (named msr): For example Intel has MSR_IA32_PERFCTRn and AMD
+ *        has MSR_K7_PERFCTRn and, for families 15H and later,
+ *        MSR_F15H_PERF_CTRn, where MSR_F15H_PERF_CTR[0-3] are
+ *        aliased to MSR_K7_PERFCTRn.
+ *     2. MSR Index (named idx): This normally is used by RDPMC instruction.
+ *        For instance AMD RDPMC instruction uses 0000_0003h in ECX to access
+ *        C001_0007h (MSR_K7_PERCTR3). Intel has a similar mechanism, except
+ *        that it also supports fixed counters. idx can be used to as index to
+ *        gp and fixed counters.
+ *     3. Global PMC Index (named pmc): pmc is an index specific to PMU
+ *        code. Each pmc, stored in kvm_pmc.idx field, is unique across
+ *        all perf counters (both gp and fixed). The mapping relationship
+ *        between pmc and perf counters is as the following:
+ *        * Intel: [0 .. KVM_INTEL_PMC_MAX_GENERIC-1] <=> gp counters
+ *                 [INTEL_PMC_IDX_FIXED .. INTEL_PMC_IDX_FIXED + 2] <=> fixed
+ *        * AMD:   [0 .. AMD64_NUM_COUNTERS-1] and, for families 15H
+ *          and later, [0 .. AMD64_NUM_COUNTERS_CORE-1] <=> gp counters
+ */
+
+static struct kvm_pmu_ops kvm_pmu_ops __read_mostly;
+
+#define KVM_X86_PMU_OP(func)					     \
+	DEFINE_STATIC_CALL_NULL(kvm_x86_pmu_##func,			     \
+				*(((struct kvm_pmu_ops *)0)->func));
+#define KVM_X86_PMU_OP_OPTIONAL KVM_X86_PMU_OP
+#include <asm/kvm-x86-pmu-ops.h>
+
+void kvm_pmu_ops_update(const struct kvm_pmu_ops *pmu_ops)
+{
+	memcpy(&kvm_pmu_ops, pmu_ops, sizeof(kvm_pmu_ops));
+
+#define __KVM_X86_PMU_OP(func) \
+	static_call_update(kvm_x86_pmu_##func, kvm_pmu_ops.func);
+#define KVM_X86_PMU_OP(func) \
+	WARN_ON(!kvm_pmu_ops.func); __KVM_X86_PMU_OP(func)
+#define KVM_X86_PMU_OP_OPTIONAL __KVM_X86_PMU_OP
+#include <asm/kvm-x86-pmu-ops.h>
+#undef __KVM_X86_PMU_OP
+}
+
+static inline void __kvm_perf_overflow(struct kvm_pmc *pmc, bool in_pmi)
+{
+	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
+	bool skip_pmi = false;
+
+	if (pmc->perf_event && pmc->perf_event->attr.precise_ip) {
+		if (!in_pmi) {
+			/*
+			 * TODO: KVM is currently _choosing_ to not generate records
+			 * for emulated instructions, avoiding BUFFER_OVF PMI when
+			 * there are no records. Strictly speaking, it should be done
+			 * as well in the right context to improve sampling accuracy.
+			 */
+			skip_pmi = true;
+		} else {
+			/* Indicate PEBS overflow PMI to guest. */
+			skip_pmi = __test_and_set_bit(GLOBAL_STATUS_BUFFER_OVF_BIT,
+						      (unsigned long *)&pmu->global_status);
+		}
+	} else {
+		__set_bit(pmc->idx, (unsigned long *)&pmu->global_status);
+	}
+
+	if (pmc->intr && !skip_pmi)
+		kvm_make_request(KVM_REQ_PMI, pmc->vcpu);
+}
+
+static void kvm_perf_overflow(struct perf_event *perf_event,
+			      struct perf_sample_data *data,
+			      struct pt_regs *regs)
+{
+	struct kvm_pmc *pmc = perf_event->overflow_handler_context;
+
+	/*
+	 * Ignore overflow events for counters that are scheduled to be
+	 * reprogrammed, e.g. if a PMI for the previous event races with KVM's
+	 * handling of a related guest WRMSR.
+	 */
+	if (test_and_set_bit(pmc->idx, pmc_to_pmu(pmc)->reprogram_pmi))
+		return;
+
+	__kvm_perf_overflow(pmc, true);
+
+	kvm_make_request(KVM_REQ_PMU, pmc->vcpu);
+}
+
+static u64 pmc_get_pebs_precise_level(struct kvm_pmc *pmc)
+{
+	/*
+	 * For some model specific pebs counters with special capabilities
+	 * (PDIR, PDIR++, PDIST), KVM needs to raise the event precise
+	 * level to the maximum value (currently 3, backwards compatible)
+	 * so that the perf subsystem would assign specific hardware counter
+	 * with that capability for vPMC.
+	 */
+	if ((pmc->idx == 0 && x86_match_cpu(vmx_pebs_pdist_cpu)) ||
+	    (pmc->idx == 32 && x86_match_cpu(vmx_pebs_pdir_cpu)))
+		return 3;
+
+	/*
+	 * The non-zero precision level of guest event makes the ordinary
+	 * guest event becomes a guest PEBS event and triggers the host
+	 * PEBS PMI handler to determine whether the PEBS overflow PMI
+	 * comes from the host counters or the guest.
+	 */
+	return 1;
+}
+
+static int pmc_reprogram_counter(struct kvm_pmc *pmc, u32 type, u64 config,
+				 bool exclude_user, bool exclude_kernel,
+				 bool intr)
+{
+	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
+	struct perf_event *event;
+	struct perf_event_attr attr = {
+		.type = type,
+		.size = sizeof(attr),
+		.pinned = true,
+		.exclude_idle = true,
+		.exclude_host = 1,
+		.exclude_user = exclude_user,
+		.exclude_kernel = exclude_kernel,
+		.config = config,
+	};
+	bool pebs = test_bit(pmc->idx, (unsigned long *)&pmu->pebs_enable);
+
+	attr.sample_period = get_sample_period(pmc, pmc->counter);
+
+	if ((attr.config & HSW_IN_TX_CHECKPOINTED) &&
+	    guest_cpuid_is_intel(pmc->vcpu)) {
+		/*
+		 * HSW_IN_TX_CHECKPOINTED is not supported with nonzero
+		 * period. Just clear the sample period so at least
+		 * allocating the counter doesn't fail.
+		 */
+		attr.sample_period = 0;
+	}
+	if (pebs) {
+		/*
+		 * For most PEBS hardware events, the difference in the software
+		 * precision levels of guest and host PEBS events will not affect
+		 * the accuracy of the PEBS profiling result, because the "event IP"
+		 * in the PEBS record is calibrated on the guest side.
+		 */
+		attr.precise_ip = pmc_get_pebs_precise_level(pmc);
+	}
+
+	event = perf_event_create_kernel_counter(&attr, -1, current,
+						 kvm_perf_overflow, pmc);
+	if (IS_ERR(event)) {
+		pr_debug_ratelimited("kvm_pmu: event creation failed %ld for pmc->idx = %d\n",
+			    PTR_ERR(event), pmc->idx);
+		return PTR_ERR(event);
+	}
+
+	pmc->perf_event = event;
+	pmc_to_pmu(pmc)->event_count++;
+	pmc->is_paused = false;
+	pmc->intr = intr || pebs;
+	return 0;
+}
+
+static void pmc_pause_counter(struct kvm_pmc *pmc)
+{
+	u64 counter = pmc->counter;
+
+	if (!pmc->perf_event || pmc->is_paused)
+		return;
+
+	/* update counter, reset event value to avoid redundant accumulation */
+	counter += perf_event_pause(pmc->perf_event, true);
+	pmc->counter = counter & pmc_bitmask(pmc);
+	pmc->is_paused = true;
+}
+
+static bool pmc_resume_counter(struct kvm_pmc *pmc)
+{
+	if (!pmc->perf_event)
+		return false;
+
+	/* recalibrate sample period and check if it's accepted by perf core */
+	if (is_sampling_event(pmc->perf_event) &&
+	    perf_event_period(pmc->perf_event,
+			      get_sample_period(pmc, pmc->counter)))
+		return false;
+
+	if (test_bit(pmc->idx, (unsigned long *)&pmc_to_pmu(pmc)->pebs_enable) !=
+	    (!!pmc->perf_event->attr.precise_ip))
+		return false;
+
+	/* reuse perf_event to serve as pmc_reprogram_counter() does*/
+	perf_event_enable(pmc->perf_event);
+	pmc->is_paused = false;
+
+	return true;
+}
+
+static void pmc_release_perf_event(struct kvm_pmc *pmc)
+{
+	if (pmc->perf_event) {
+		perf_event_release_kernel(pmc->perf_event);
+		pmc->perf_event = NULL;
+		pmc->current_config = 0;
+		pmc_to_pmu(pmc)->event_count--;
+	}
+}
+
+static void pmc_stop_counter(struct kvm_pmc *pmc)
+{
+	if (pmc->perf_event) {
+		pmc->counter = pmc_read_counter(pmc);
+		pmc_release_perf_event(pmc);
+	}
+}
+
+static int filter_cmp(const void *pa, const void *pb, u64 mask)
+{
+	u64 a = *(u64 *)pa & mask;
+	u64 b = *(u64 *)pb & mask;
+
+	return (a > b) - (a < b);
+}
+
+
+static int filter_sort_cmp(const void *pa, const void *pb)
+{
+	return filter_cmp(pa, pb, (KVM_PMU_MASKED_ENTRY_EVENT_SELECT |
+				   KVM_PMU_MASKED_ENTRY_EXCLUDE));
+}
+
+/*
+ * For the event filter, searching is done on the 'includes' list and
+ * 'excludes' list separately rather than on the 'events' list (which
+ * has both).  As a result the exclude bit can be ignored.
+ */
+static int filter_event_cmp(const void *pa, const void *pb)
+{
+	return filter_cmp(pa, pb, (KVM_PMU_MASKED_ENTRY_EVENT_SELECT));
+}
+
+static int find_filter_index(u64 *events, u64 nevents, u64 key)
+{
+	u64 *fe = bsearch(&key, events, nevents, sizeof(events[0]),
+			  filter_event_cmp);
+
+	if (!fe)
+		return -1;
+
+	return fe - events;
+}
+
+static bool is_filter_entry_match(u64 filter_event, u64 umask)
+{
+	u64 mask = filter_event >> (KVM_PMU_MASKED_ENTRY_UMASK_MASK_SHIFT - 8);
+	u64 match = filter_event & KVM_PMU_MASKED_ENTRY_UMASK_MATCH;
+
+	BUILD_BUG_ON((KVM_PMU_ENCODE_MASKED_ENTRY(0, 0xff, 0, false) >>
+		     (KVM_PMU_MASKED_ENTRY_UMASK_MASK_SHIFT - 8)) !=
+		     ARCH_PERFMON_EVENTSEL_UMASK);
+
+	return (umask & mask) == match;
+}
+
+static bool filter_contains_match(u64 *events, u64 nevents, u64 eventsel)
+{
+	u64 event_select = eventsel & kvm_pmu_ops.EVENTSEL_EVENT;
+	u64 umask = eventsel & ARCH_PERFMON_EVENTSEL_UMASK;
+	int i, index;
+
+	index = find_filter_index(events, nevents, event_select);
+	if (index < 0)
+		return false;
+
+	/*
+	 * Entries are sorted by the event select.  Walk the list in both
+	 * directions to process all entries with the targeted event select.
+	 */
+	for (i = index; i < nevents; i++) {
+		if (filter_event_cmp(&events[i], &event_select))
+			break;
+
+		if (is_filter_entry_match(events[i], umask))
+			return true;
+	}
+
+	for (i = index - 1; i >= 0; i--) {
+		if (filter_event_cmp(&events[i], &event_select))
+			break;
+
+		if (is_filter_entry_match(events[i], umask))
+			return true;
+	}
+
+	return false;
+}
+
+static bool is_gp_event_allowed(struct kvm_x86_pmu_event_filter *f,
+				u64 eventsel)
+{
+	if (filter_contains_match(f->includes, f->nr_includes, eventsel) &&
+	    !filter_contains_match(f->excludes, f->nr_excludes, eventsel))
+		return f->action == KVM_PMU_EVENT_ALLOW;
+
+	return f->action == KVM_PMU_EVENT_DENY;
+}
+
+static bool is_fixed_event_allowed(struct kvm_x86_pmu_event_filter *filter,
+				   int idx)
+{
+	int fixed_idx = idx - INTEL_PMC_IDX_FIXED;
+
+	if (filter->action == KVM_PMU_EVENT_DENY &&
+	    test_bit(fixed_idx, (ulong *)&filter->fixed_counter_bitmap))
+		return false;
+	if (filter->action == KVM_PMU_EVENT_ALLOW &&
+	    !test_bit(fixed_idx, (ulong *)&filter->fixed_counter_bitmap))
+		return false;
+
+	return true;
+}
+
+static bool check_pmu_event_filter(struct kvm_pmc *pmc)
+{
+	struct kvm_x86_pmu_event_filter *filter;
+	struct kvm *kvm = pmc->vcpu->kvm;
+
+	filter = srcu_dereference(kvm->arch.pmu_event_filter, &kvm->srcu);
+	if (!filter)
+		return true;
+
+	if (pmc_is_gp(pmc))
+		return is_gp_event_allowed(filter, pmc->eventsel);
+
+	return is_fixed_event_allowed(filter, pmc->idx);
+}
+
+static bool pmc_event_is_allowed(struct kvm_pmc *pmc)
+{
+	return pmc_is_globally_enabled(pmc) && pmc_speculative_in_use(pmc) &&
+	       static_call(kvm_x86_pmu_hw_event_available)(pmc) &&
+	       check_pmu_event_filter(pmc);
+}
+
+static void reprogram_counter(struct kvm_pmc *pmc)
+{
+	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
+	u64 eventsel = pmc->eventsel;
+	u64 new_config = eventsel;
+	u8 fixed_ctr_ctrl;
+
+	pmc_pause_counter(pmc);
+
+	if (!pmc_event_is_allowed(pmc))
+		goto reprogram_complete;
+
+	if (pmc->counter < pmc->prev_counter)
+		__kvm_perf_overflow(pmc, false);
+
+	if (eventsel & ARCH_PERFMON_EVENTSEL_PIN_CONTROL)
+		printk_once("kvm pmu: pin control bit is ignored\n");
+
+	if (pmc_is_fixed(pmc)) {
+		fixed_ctr_ctrl = fixed_ctrl_field(pmu->fixed_ctr_ctrl,
+						  pmc->idx - INTEL_PMC_IDX_FIXED);
+		if (fixed_ctr_ctrl & 0x1)
+			eventsel |= ARCH_PERFMON_EVENTSEL_OS;
+		if (fixed_ctr_ctrl & 0x2)
+			eventsel |= ARCH_PERFMON_EVENTSEL_USR;
+		if (fixed_ctr_ctrl & 0x8)
+			eventsel |= ARCH_PERFMON_EVENTSEL_INT;
+		new_config = (u64)fixed_ctr_ctrl;
+	}
+
+	if (pmc->current_config == new_config && pmc_resume_counter(pmc))
+		goto reprogram_complete;
+
+	pmc_release_perf_event(pmc);
+
+	pmc->current_config = new_config;
+
+	/*
+	 * If reprogramming fails, e.g. due to contention, leave the counter's
+	 * regprogram bit set, i.e. opportunistically try again on the next PMU
+	 * refresh.  Don't make a new request as doing so can stall the guest
+	 * if reprogramming repeatedly fails.
+	 */
+	if (pmc_reprogram_counter(pmc, PERF_TYPE_RAW,
+				  (eventsel & pmu->raw_event_mask),
+				  !(eventsel & ARCH_PERFMON_EVENTSEL_USR),
+				  !(eventsel & ARCH_PERFMON_EVENTSEL_OS),
+				  eventsel & ARCH_PERFMON_EVENTSEL_INT))
+		return;
+
+reprogram_complete:
+	clear_bit(pmc->idx, (unsigned long *)&pmc_to_pmu(pmc)->reprogram_pmi);
+	pmc->prev_counter = 0;
+}
+
+void kvm_pmu_handle_event(struct kvm_vcpu *vcpu)
+{
+	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+	int bit;
+
+	for_each_set_bit(bit, pmu->reprogram_pmi, X86_PMC_IDX_MAX) {
+		struct kvm_pmc *pmc = static_call(kvm_x86_pmu_pmc_idx_to_pmc)(pmu, bit);
+
+		if (unlikely(!pmc)) {
+			clear_bit(bit, pmu->reprogram_pmi);
+			continue;
+		}
+
+		reprogram_counter(pmc);
+	}
+
+	/*
+	 * Unused perf_events are only released if the corresponding MSRs
+	 * weren't accessed during the last vCPU time slice. kvm_arch_sched_in
+	 * triggers KVM_REQ_PMU if cleanup is needed.
+	 */
+	if (unlikely(pmu->need_cleanup))
+		kvm_pmu_cleanup(vcpu);
+}
+
+/* check if idx is a valid index to access PMU */
+bool kvm_pmu_is_valid_rdpmc_ecx(struct kvm_vcpu *vcpu, unsigned int idx)
+{
+	return static_call(kvm_x86_pmu_is_valid_rdpmc_ecx)(vcpu, idx);
+}
+
+bool is_vmware_backdoor_pmc(u32 pmc_idx)
+{
+	switch (pmc_idx) {
+	case VMWARE_BACKDOOR_PMC_HOST_TSC:
+	case VMWARE_BACKDOOR_PMC_REAL_TIME:
+	case VMWARE_BACKDOOR_PMC_APPARENT_TIME:
+		return true;
+	}
+	return false;
+}
+
+static int kvm_pmu_rdpmc_vmware(struct kvm_vcpu *vcpu, unsigned idx, u64 *data)
+{
+	u64 ctr_val;
+
+	switch (idx) {
+	case VMWARE_BACKDOOR_PMC_HOST_TSC:
+		ctr_val = rdtsc();
+		break;
+	case VMWARE_BACKDOOR_PMC_REAL_TIME:
+		ctr_val = ktime_get_boottime_ns();
+		break;
+	case VMWARE_BACKDOOR_PMC_APPARENT_TIME:
+		ctr_val = ktime_get_boottime_ns() +
+			vcpu->kvm->arch.kvmclock_offset;
+		break;
+	default:
+		return 1;
+	}
+
+	*data = ctr_val;
+	return 0;
+}
+
+int kvm_pmu_rdpmc(struct kvm_vcpu *vcpu, unsigned idx, u64 *data)
+{
+	bool fast_mode = idx & (1u << 31);
+	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+	struct kvm_pmc *pmc;
+	u64 mask = fast_mode ? ~0u : ~0ull;
+
+	if (!pmu->version)
+		return 1;
+
+	if (is_vmware_backdoor_pmc(idx))
+		return kvm_pmu_rdpmc_vmware(vcpu, idx, data);
+
+	pmc = static_call(kvm_x86_pmu_rdpmc_ecx_to_pmc)(vcpu, idx, &mask);
+	if (!pmc)
+		return 1;
+
+	if (!kvm_is_cr4_bit_set(vcpu, X86_CR4_PCE) &&
+	    (static_call(kvm_x86_get_cpl)(vcpu) != 0) &&
+	    kvm_is_cr0_bit_set(vcpu, X86_CR0_PE))
+		return 1;
+
+	*data = pmc_read_counter(pmc) & mask;
+	return 0;
+}
+
+void kvm_pmu_deliver_pmi(struct kvm_vcpu *vcpu)
+{
+	if (lapic_in_kernel(vcpu)) {
+		static_call_cond(kvm_x86_pmu_deliver_pmi)(vcpu);
+		kvm_apic_local_deliver(vcpu->arch.apic, APIC_LVTPC);
+	}
+}
+
+bool kvm_pmu_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr)
+{
+	switch (msr) {
+	case MSR_CORE_PERF_GLOBAL_STATUS:
+	case MSR_CORE_PERF_GLOBAL_CTRL:
+	case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
+		return kvm_pmu_has_perf_global_ctrl(vcpu_to_pmu(vcpu));
+	default:
+		break;
+	}
+	return static_call(kvm_x86_pmu_msr_idx_to_pmc)(vcpu, msr) ||
+		static_call(kvm_x86_pmu_is_valid_msr)(vcpu, msr);
+}
+
+static void kvm_pmu_mark_pmc_in_use(struct kvm_vcpu *vcpu, u32 msr)
+{
+	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+	struct kvm_pmc *pmc = static_call(kvm_x86_pmu_msr_idx_to_pmc)(vcpu, msr);
+
+	if (pmc)
+		__set_bit(pmc->idx, pmu->pmc_in_use);
+}
+
+int kvm_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
+{
+	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+	u32 msr = msr_info->index;
+
+	switch (msr) {
+	case MSR_CORE_PERF_GLOBAL_STATUS:
+	case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS:
+		msr_info->data = pmu->global_status;
+		break;
+	case MSR_AMD64_PERF_CNTR_GLOBAL_CTL:
+	case MSR_CORE_PERF_GLOBAL_CTRL:
+		msr_info->data = pmu->global_ctrl;
+		break;
+	case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR:
+	case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
+		msr_info->data = 0;
+		break;
+	default:
+		return static_call(kvm_x86_pmu_get_msr)(vcpu, msr_info);
+	}
+
+	return 0;
+}
+
+int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
+{
+	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+	u32 msr = msr_info->index;
+	u64 data = msr_info->data;
+	u64 diff;
+
+	/*
+	 * Note, AMD ignores writes to reserved bits and read-only PMU MSRs,
+	 * whereas Intel generates #GP on attempts to write reserved/RO MSRs.
+	 */
+	switch (msr) {
+	case MSR_CORE_PERF_GLOBAL_STATUS:
+		if (!msr_info->host_initiated)
+			return 1; /* RO MSR */
+		fallthrough;
+	case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS:
+		/* Per PPR, Read-only MSR. Writes are ignored. */
+		if (!msr_info->host_initiated)
+			break;
+
+		if (data & pmu->global_status_mask)
+			return 1;
+
+		pmu->global_status = data;
+		break;
+	case MSR_AMD64_PERF_CNTR_GLOBAL_CTL:
+		data &= ~pmu->global_ctrl_mask;
+		fallthrough;
+	case MSR_CORE_PERF_GLOBAL_CTRL:
+		if (!kvm_valid_perf_global_ctrl(pmu, data))
+			return 1;
+
+		if (pmu->global_ctrl != data) {
+			diff = pmu->global_ctrl ^ data;
+			pmu->global_ctrl = data;
+			reprogram_counters(pmu, diff);
+		}
+		break;
+	case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
+		/*
+		 * GLOBAL_OVF_CTRL, a.k.a. GLOBAL STATUS_RESET, clears bits in
+		 * GLOBAL_STATUS, and so the set of reserved bits is the same.
+		 */
+		if (data & pmu->global_status_mask)
+			return 1;
+		fallthrough;
+	case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR:
+		if (!msr_info->host_initiated)
+			pmu->global_status &= ~data;
+		break;
+	default:
+		kvm_pmu_mark_pmc_in_use(vcpu, msr_info->index);
+		return static_call(kvm_x86_pmu_set_msr)(vcpu, msr_info);
+	}
+
+	return 0;
+}
+
+void kvm_pmu_reset(struct kvm_vcpu *vcpu)
+{
+	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+	struct kvm_pmc *pmc;
+	int i;
+
+	pmu->need_cleanup = false;
+
+	bitmap_zero(pmu->reprogram_pmi, X86_PMC_IDX_MAX);
+
+	for_each_set_bit(i, pmu->all_valid_pmc_idx, X86_PMC_IDX_MAX) {
+		pmc = static_call(kvm_x86_pmu_pmc_idx_to_pmc)(pmu, i);
+		if (!pmc)
+			continue;
+
+		pmc_stop_counter(pmc);
+		pmc->counter = 0;
+
+		if (pmc_is_gp(pmc))
+			pmc->eventsel = 0;
+	}
+
+	pmu->fixed_ctr_ctrl = pmu->global_ctrl = pmu->global_status = 0;
+
+	static_call_cond(kvm_x86_pmu_reset)(vcpu);
+}
+
+
+/*
+ * Refresh the PMU configuration for the vCPU, e.g. if userspace changes CPUID
+ * and/or PERF_CAPABILITIES.
+ */
+void kvm_pmu_refresh(struct kvm_vcpu *vcpu)
+{
+	if (KVM_BUG_ON(kvm_vcpu_has_run(vcpu), vcpu->kvm))
+		return;
+
+	/*
+	 * Stop/release all existing counters/events before realizing the new
+	 * vPMU model.
+	 */
+	kvm_pmu_reset(vcpu);
+
+	bitmap_zero(vcpu_to_pmu(vcpu)->all_valid_pmc_idx, X86_PMC_IDX_MAX);
+	static_call(kvm_x86_pmu_refresh)(vcpu);
+}
+
+void kvm_pmu_init(struct kvm_vcpu *vcpu)
+{
+	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+
+	memset(pmu, 0, sizeof(*pmu));
+	static_call(kvm_x86_pmu_init)(vcpu);
+	pmu->event_count = 0;
+	pmu->need_cleanup = false;
+	kvm_pmu_refresh(vcpu);
+}
+
+/* Release perf_events for vPMCs that have been unused for a full time slice.  */
+void kvm_pmu_cleanup(struct kvm_vcpu *vcpu)
+{
+	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+	struct kvm_pmc *pmc = NULL;
+	DECLARE_BITMAP(bitmask, X86_PMC_IDX_MAX);
+	int i;
+
+	pmu->need_cleanup = false;
+
+	bitmap_andnot(bitmask, pmu->all_valid_pmc_idx,
+		      pmu->pmc_in_use, X86_PMC_IDX_MAX);
+
+	for_each_set_bit(i, bitmask, X86_PMC_IDX_MAX) {
+		pmc = static_call(kvm_x86_pmu_pmc_idx_to_pmc)(pmu, i);
+
+		if (pmc && pmc->perf_event && !pmc_speculative_in_use(pmc))
+			pmc_stop_counter(pmc);
+	}
+
+	static_call_cond(kvm_x86_pmu_cleanup)(vcpu);
+
+	bitmap_zero(pmu->pmc_in_use, X86_PMC_IDX_MAX);
+}
+
+void kvm_pmu_destroy(struct kvm_vcpu *vcpu)
+{
+	kvm_pmu_reset(vcpu);
+}
+
+static void kvm_pmu_incr_counter(struct kvm_pmc *pmc)
+{
+	pmc->prev_counter = pmc->counter;
+	pmc->counter = (pmc->counter + 1) & pmc_bitmask(pmc);
+	kvm_pmu_request_counter_reprogram(pmc);
+}
+
+static inline bool eventsel_match_perf_hw_id(struct kvm_pmc *pmc,
+	unsigned int perf_hw_id)
+{
+	return !((pmc->eventsel ^ perf_get_hw_event_config(perf_hw_id)) &
+		AMD64_RAW_EVENT_MASK_NB);
+}
+
+static inline bool cpl_is_matched(struct kvm_pmc *pmc)
+{
+	bool select_os, select_user;
+	u64 config;
+
+	if (pmc_is_gp(pmc)) {
+		config = pmc->eventsel;
+		select_os = config & ARCH_PERFMON_EVENTSEL_OS;
+		select_user = config & ARCH_PERFMON_EVENTSEL_USR;
+	} else {
+		config = fixed_ctrl_field(pmc_to_pmu(pmc)->fixed_ctr_ctrl,
+					  pmc->idx - INTEL_PMC_IDX_FIXED);
+		select_os = config & 0x1;
+		select_user = config & 0x2;
+	}
+
+	return (static_call(kvm_x86_get_cpl)(pmc->vcpu) == 0) ? select_os : select_user;
+}
+
+void kvm_pmu_trigger_event(struct kvm_vcpu *vcpu, u64 perf_hw_id)
+{
+	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+	struct kvm_pmc *pmc;
+	int i;
+
+	for_each_set_bit(i, pmu->all_valid_pmc_idx, X86_PMC_IDX_MAX) {
+		pmc = static_call(kvm_x86_pmu_pmc_idx_to_pmc)(pmu, i);
+
+		if (!pmc || !pmc_event_is_allowed(pmc))
+			continue;
+
+		/* Ignore checks for edge detect, pin control, invert and CMASK bits */
+		if (eventsel_match_perf_hw_id(pmc, perf_hw_id) && cpl_is_matched(pmc))
+			kvm_pmu_incr_counter(pmc);
+	}
+}
+EXPORT_SYMBOL_GPL(kvm_pmu_trigger_event);
+
+static bool is_masked_filter_valid(const struct kvm_x86_pmu_event_filter *filter)
+{
+	u64 mask = kvm_pmu_ops.EVENTSEL_EVENT |
+		   KVM_PMU_MASKED_ENTRY_UMASK_MASK |
+		   KVM_PMU_MASKED_ENTRY_UMASK_MATCH |
+		   KVM_PMU_MASKED_ENTRY_EXCLUDE;
+	int i;
+
+	for (i = 0; i < filter->nevents; i++) {
+		if (filter->events[i] & ~mask)
+			return false;
+	}
+
+	return true;
+}
+
+static void convert_to_masked_filter(struct kvm_x86_pmu_event_filter *filter)
+{
+	int i, j;
+
+	for (i = 0, j = 0; i < filter->nevents; i++) {
+		/*
+		 * Skip events that are impossible to match against a guest
+		 * event.  When filtering, only the event select + unit mask
+		 * of the guest event is used.  To maintain backwards
+		 * compatibility, impossible filters can't be rejected :-(
+		 */
+		if (filter->events[i] & ~(kvm_pmu_ops.EVENTSEL_EVENT |
+					  ARCH_PERFMON_EVENTSEL_UMASK))
+			continue;
+		/*
+		 * Convert userspace events to a common in-kernel event so
+		 * only one code path is needed to support both events.  For
+		 * the in-kernel events use masked events because they are
+		 * flexible enough to handle both cases.  To convert to masked
+		 * events all that's needed is to add an "all ones" umask_mask,
+		 * (unmasked filter events don't support EXCLUDE).
+		 */
+		filter->events[j++] = filter->events[i] |
+				      (0xFFULL << KVM_PMU_MASKED_ENTRY_UMASK_MASK_SHIFT);
+	}
+
+	filter->nevents = j;
+}
+
+static int prepare_filter_lists(struct kvm_x86_pmu_event_filter *filter)
+{
+	int i;
+
+	if (!(filter->flags & KVM_PMU_EVENT_FLAG_MASKED_EVENTS))
+		convert_to_masked_filter(filter);
+	else if (!is_masked_filter_valid(filter))
+		return -EINVAL;
+
+	/*
+	 * Sort entries by event select and includes vs. excludes so that all
+	 * entries for a given event select can be processed efficiently during
+	 * filtering.  The EXCLUDE flag uses a more significant bit than the
+	 * event select, and so the sorted list is also effectively split into
+	 * includes and excludes sub-lists.
+	 */
+	sort(&filter->events, filter->nevents, sizeof(filter->events[0]),
+	     filter_sort_cmp, NULL);
+
+	i = filter->nevents;
+	/* Find the first EXCLUDE event (only supported for masked events). */
+	if (filter->flags & KVM_PMU_EVENT_FLAG_MASKED_EVENTS) {
+		for (i = 0; i < filter->nevents; i++) {
+			if (filter->events[i] & KVM_PMU_MASKED_ENTRY_EXCLUDE)
+				break;
+		}
+	}
+
+	filter->nr_includes = i;
+	filter->nr_excludes = filter->nevents - filter->nr_includes;
+	filter->includes = filter->events;
+	filter->excludes = filter->events + filter->nr_includes;
+
+	return 0;
+}
+
+int kvm_vm_ioctl_set_pmu_event_filter(struct kvm *kvm, void __user *argp)
+{
+	struct kvm_pmu_event_filter __user *user_filter = argp;
+	struct kvm_x86_pmu_event_filter *filter;
+	struct kvm_pmu_event_filter tmp;
+	struct kvm_vcpu *vcpu;
+	unsigned long i;
+	size_t size;
+	int r;
+
+	if (copy_from_user(&tmp, user_filter, sizeof(tmp)))
+		return -EFAULT;
+
+	if (tmp.action != KVM_PMU_EVENT_ALLOW &&
+	    tmp.action != KVM_PMU_EVENT_DENY)
+		return -EINVAL;
+
+	if (tmp.flags & ~KVM_PMU_EVENT_FLAGS_VALID_MASK)
+		return -EINVAL;
+
+	if (tmp.nevents > KVM_PMU_EVENT_FILTER_MAX_EVENTS)
+		return -E2BIG;
+
+	size = struct_size(filter, events, tmp.nevents);
+	filter = kzalloc(size, GFP_KERNEL_ACCOUNT);
+	if (!filter)
+		return -ENOMEM;
+
+	filter->action = tmp.action;
+	filter->nevents = tmp.nevents;
+	filter->fixed_counter_bitmap = tmp.fixed_counter_bitmap;
+	filter->flags = tmp.flags;
+
+	r = -EFAULT;
+	if (copy_from_user(filter->events, user_filter->events,
+			   sizeof(filter->events[0]) * filter->nevents))
+		goto cleanup;
+
+	r = prepare_filter_lists(filter);
+	if (r)
+		goto cleanup;
+
+	mutex_lock(&kvm->lock);
+	filter = rcu_replace_pointer(kvm->arch.pmu_event_filter, filter,
+				     mutex_is_locked(&kvm->lock));
+	mutex_unlock(&kvm->lock);
+	synchronize_srcu_expedited(&kvm->srcu);
+
+	BUILD_BUG_ON(sizeof(((struct kvm_pmu *)0)->reprogram_pmi) >
+		     sizeof(((struct kvm_pmu *)0)->__reprogram_pmi));
+
+	kvm_for_each_vcpu(i, vcpu, kvm)
+		atomic64_set(&vcpu_to_pmu(vcpu)->__reprogram_pmi, -1ull);
+
+	kvm_make_all_cpus_request(kvm, KVM_REQ_PMU);
+
+	r = 0;
+cleanup:
+	kfree(filter);
+	return r;
+}