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-rw-r--r--arch/x86/kernel/cpu/vmware.c528
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diff --git a/arch/x86/kernel/cpu/vmware.c b/arch/x86/kernel/cpu/vmware.c
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+++ b/arch/x86/kernel/cpu/vmware.c
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+/*
+ * 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
+};
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