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authorSang-Heon Jeon <ekffu200098@gmail.com>2026-08-24 01:18:14 +0900
committerJulia Lawall <Julia.Lawall@inria.fr>2026-08-23 22:12:11 +0200
commit2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c (patch)
treedcc4da1d99f17541c5590ac63c77da4bf372a4ab /arch/x86/kvm/cpuid.c
downloadlinux-stable-2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c.tar.gz
linux-stable-2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c.zip
coccinelle: alloc_cast: drop removed allocatorsgrafted
- pci_alloc_consistent() and pci_zalloc_consistent() were removed by commit 7968778914e5 ("PCI: Remove the deprecated "pci-dma-compat.h" API") - kmem_alloc() was removed by commit f078d4ea8276 ("xfs: convert kmem_alloc() to kmalloc()") - kmem_zalloc() was removed by commit 10634530f7ba ("xfs: convert kmem_zalloc() to kzalloc()") - kmem_zone_alloc() and kmem_zone_zalloc() were removed by commit bae633a4a283 ("xfs: remove xfs_zone_{alloc,zalloc} helpers") So drop them from the rules. No functional change. Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com> Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Diffstat (limited to 'arch/x86/kvm/cpuid.c')
-rw-r--r--arch/x86/kvm/cpuid.c2178
1 files changed, 2178 insertions, 0 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
new file mode 100644
index 000000000..00d909ddb
--- /dev/null
+++ b/arch/x86/kvm/cpuid.c
@@ -0,0 +1,2178 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Kernel-based Virtual Machine driver for Linux
+ * cpuid support routines
+ *
+ * derived from arch/x86/kvm/x86.c
+ *
+ * Copyright 2011 Red Hat, Inc. and/or its affiliates.
+ * Copyright IBM Corporation, 2008
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kvm_host.h>
+#include <linux/lockdep.h>
+#include <linux/export.h>
+#include <linux/vmalloc.h>
+#include <linux/uaccess.h>
+#include <linux/sched/stat.h>
+
+#include <asm/processor.h>
+#include <asm/user.h>
+#include <asm/fpu/xstate.h>
+#include <asm/sgx.h>
+#include <asm/cpuid/api.h>
+#include "cpuid.h"
+#include "lapic.h"
+#include "mmu.h"
+#include "trace.h"
+#include "pmu.h"
+#include "xen.h"
+
+/*
+ * Unlike "struct cpuinfo_x86.x86_capability", kvm_cpu_caps doesn't need to be
+ * aligned to sizeof(unsigned long) because it's not accessed via bitops.
+ */
+u32 kvm_cpu_caps[NR_KVM_CPU_CAPS] __read_mostly;
+EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_cpu_caps);
+
+bool kvm_is_configuring_cpu_caps __read_mostly;
+EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_is_configuring_cpu_caps);
+
+struct cpuid_xstate_sizes {
+ u32 eax;
+ u32 ebx;
+ u32 ecx;
+};
+
+static struct cpuid_xstate_sizes xstate_sizes[XFEATURE_MAX] __ro_after_init;
+
+void __init kvm_init_xstate_sizes(void)
+{
+ u32 ign;
+ int i;
+
+ for (i = XFEATURE_YMM; i < ARRAY_SIZE(xstate_sizes); i++) {
+ struct cpuid_xstate_sizes *xs = &xstate_sizes[i];
+
+ cpuid_count(0xD, i, &xs->eax, &xs->ebx, &xs->ecx, &ign);
+ }
+}
+
+u32 xstate_required_size(u64 xstate_bv, bool compacted)
+{
+ u32 ret = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
+ int i;
+
+ xstate_bv &= XFEATURE_MASK_EXTEND;
+ for (i = XFEATURE_YMM; i < ARRAY_SIZE(xstate_sizes) && xstate_bv; i++) {
+ struct cpuid_xstate_sizes *xs = &xstate_sizes[i];
+ u32 offset;
+
+ if (!(xstate_bv & BIT_ULL(i)))
+ continue;
+
+ /* ECX[1]: 64B alignment in compacted form */
+ if (compacted)
+ offset = (xs->ecx & 0x2) ? ALIGN(ret, 64) : ret;
+ else
+ offset = xs->ebx;
+ ret = max(ret, offset + xs->eax);
+ xstate_bv &= ~BIT_ULL(i);
+ }
+
+ return ret;
+}
+
+struct kvm_cpuid_entry2 *kvm_find_cpuid_entry2(
+ struct kvm_cpuid_entry2 *entries, int nent, u32 function, u64 index)
+{
+ struct kvm_cpuid_entry2 *e;
+ int i;
+
+ /*
+ * KVM has a semi-arbitrary rule that querying the guest's CPUID model
+ * with IRQs disabled is disallowed. The CPUID model can legitimately
+ * have over one hundred entries, i.e. the lookup is slow, and IRQs are
+ * typically disabled in KVM only when KVM is in a performance critical
+ * path, e.g. the core VM-Enter/VM-Exit run loop. Nothing will break
+ * if this rule is violated, this assertion is purely to flag potential
+ * performance issues. If this fires, consider moving the lookup out
+ * of the hotpath, e.g. by caching information during CPUID updates.
+ */
+ lockdep_assert_irqs_enabled();
+
+ for (i = 0; i < nent; i++) {
+ e = &entries[i];
+
+ if (e->function != function)
+ continue;
+
+ /*
+ * If the index isn't significant, use the first entry with a
+ * matching function. It's userspace's responsibility to not
+ * provide "duplicate" entries in all cases.
+ */
+ if (!(e->flags & KVM_CPUID_FLAG_SIGNIFCANT_INDEX) || e->index == index)
+ return e;
+
+
+ /*
+ * Similarly, use the first matching entry if KVM is doing a
+ * lookup (as opposed to emulating CPUID) for a function that's
+ * architecturally defined as not having a significant index.
+ */
+ if (index == KVM_CPUID_INDEX_NOT_SIGNIFICANT) {
+ /*
+ * Direct lookups from KVM should not diverge from what
+ * KVM defines internally (the architectural behavior).
+ */
+ WARN_ON_ONCE(cpuid_function_is_indexed(function));
+ return e;
+ }
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_find_cpuid_entry2);
+
+static int kvm_check_cpuid(struct kvm_vcpu *vcpu)
+{
+ struct kvm_cpuid_entry2 *best;
+ u64 xfeatures;
+
+ /*
+ * The existing code assumes virtual address is 48-bit or 57-bit in the
+ * canonical address checks; exit if it is ever changed.
+ */
+ best = kvm_find_cpuid_entry(vcpu, 0x80000008);
+ if (best) {
+ int vaddr_bits = (best->eax & 0xff00) >> 8;
+
+ if (vaddr_bits != 48 && vaddr_bits != 57 && vaddr_bits != 0)
+ return -EINVAL;
+ }
+
+ /*
+ * Exposing dynamic xfeatures to the guest requires additional
+ * enabling in the FPU, e.g. to expand the guest XSAVE state size.
+ */
+ best = kvm_find_cpuid_entry_index(vcpu, 0xd, 0);
+ if (!best)
+ return 0;
+
+ xfeatures = best->eax | ((u64)best->edx << 32);
+ xfeatures &= XFEATURE_MASK_USER_DYNAMIC;
+ if (!xfeatures)
+ return 0;
+
+ return fpu_enable_guest_xfd_features(&vcpu->arch.guest_fpu, xfeatures);
+}
+
+static u32 kvm_apply_cpuid_pv_features_quirk(struct kvm_vcpu *vcpu);
+static void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu);
+
+/* Check whether the supplied CPUID data is equal to what is already set for the vCPU. */
+static int kvm_cpuid_check_equal(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *e2,
+ int nent)
+{
+ struct kvm_cpuid_entry2 *orig;
+ int i;
+
+ /*
+ * Apply runtime CPUID updates to the incoming CPUID entries to avoid
+ * false positives due mismatches on KVM-owned feature flags.
+ *
+ * Note! @e2 and @nent track the _old_ CPUID entries!
+ */
+ kvm_update_cpuid_runtime(vcpu);
+ kvm_apply_cpuid_pv_features_quirk(vcpu);
+
+ if (nent != vcpu->arch.cpuid_nent)
+ return -EINVAL;
+
+ for (i = 0; i < nent; i++) {
+ orig = &vcpu->arch.cpuid_entries[i];
+ if (e2[i].function != orig->function ||
+ e2[i].index != orig->index ||
+ e2[i].flags != orig->flags ||
+ e2[i].eax != orig->eax || e2[i].ebx != orig->ebx ||
+ e2[i].ecx != orig->ecx || e2[i].edx != orig->edx)
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static struct kvm_hypervisor_cpuid kvm_get_hypervisor_cpuid(struct kvm_vcpu *vcpu,
+ const char *sig)
+{
+ struct kvm_hypervisor_cpuid cpuid = {};
+ struct kvm_cpuid_entry2 *entry;
+ u32 base;
+
+ for_each_possible_cpuid_base_hypervisor(base) {
+ entry = kvm_find_cpuid_entry(vcpu, base);
+
+ if (entry) {
+ u32 signature[3];
+
+ signature[0] = entry->ebx;
+ signature[1] = entry->ecx;
+ signature[2] = entry->edx;
+
+ if (!memcmp(signature, sig, sizeof(signature))) {
+ cpuid.base = base;
+ cpuid.limit = entry->eax;
+ break;
+ }
+ }
+ }
+
+ return cpuid;
+}
+
+static u32 kvm_apply_cpuid_pv_features_quirk(struct kvm_vcpu *vcpu)
+{
+ struct kvm_hypervisor_cpuid kvm_cpuid;
+ struct kvm_cpuid_entry2 *best;
+
+ kvm_cpuid = kvm_get_hypervisor_cpuid(vcpu, KVM_SIGNATURE);
+ if (!kvm_cpuid.base)
+ return 0;
+
+ best = kvm_find_cpuid_entry(vcpu, kvm_cpuid.base | KVM_CPUID_FEATURES);
+ if (!best)
+ return 0;
+
+ if (kvm_hlt_in_guest(vcpu->kvm))
+ best->eax &= ~(1 << KVM_FEATURE_PV_UNHALT);
+
+ return best->eax;
+}
+
+/*
+ * Calculate guest's supported XCR0 taking into account guest CPUID data and
+ * KVM's supported XCR0 (comprised of host's XCR0 and KVM_SUPPORTED_XCR0).
+ */
+static u64 cpuid_get_supported_xcr0(struct kvm_vcpu *vcpu)
+{
+ struct kvm_cpuid_entry2 *best;
+
+ best = kvm_find_cpuid_entry_index(vcpu, 0xd, 0);
+ if (!best)
+ return 0;
+
+ return (best->eax | ((u64)best->edx << 32)) & kvm_caps.supported_xcr0;
+}
+
+static u64 cpuid_get_supported_xss(struct kvm_vcpu *vcpu)
+{
+ struct kvm_cpuid_entry2 *best;
+
+ best = kvm_find_cpuid_entry_index(vcpu, 0xd, 1);
+ if (!best)
+ return 0;
+
+ return (best->ecx | ((u64)best->edx << 32)) & kvm_caps.supported_xss;
+}
+
+static __always_inline void kvm_update_feature_runtime(struct kvm_vcpu *vcpu,
+ struct kvm_cpuid_entry2 *entry,
+ unsigned int x86_feature,
+ bool has_feature)
+{
+ cpuid_entry_change(entry, x86_feature, has_feature);
+ guest_cpu_cap_change(vcpu, x86_feature, has_feature);
+}
+
+static void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
+{
+ struct kvm_cpuid_entry2 *best;
+
+ vcpu->arch.cpuid_dynamic_bits_dirty = false;
+
+ best = kvm_find_cpuid_entry(vcpu, 1);
+ if (best) {
+ kvm_update_feature_runtime(vcpu, best, X86_FEATURE_OSXSAVE,
+ kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE));
+
+ kvm_update_feature_runtime(vcpu, best, X86_FEATURE_APIC,
+ vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE);
+
+ if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT))
+ kvm_update_feature_runtime(vcpu, best, X86_FEATURE_MWAIT,
+ vcpu->arch.ia32_misc_enable_msr &
+ MSR_IA32_MISC_ENABLE_MWAIT);
+ }
+
+ best = kvm_find_cpuid_entry_index(vcpu, 7, 0);
+ if (best)
+ kvm_update_feature_runtime(vcpu, best, X86_FEATURE_OSPKE,
+ kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE));
+
+
+ best = kvm_find_cpuid_entry_index(vcpu, 0xD, 0);
+ if (best)
+ best->ebx = xstate_required_size(vcpu->arch.xcr0, false);
+
+ best = kvm_find_cpuid_entry_index(vcpu, 0xD, 1);
+ if (best && (cpuid_entry_has(best, X86_FEATURE_XSAVES) ||
+ cpuid_entry_has(best, X86_FEATURE_XSAVEC)))
+ best->ebx = xstate_required_size(vcpu->arch.xcr0 |
+ vcpu->arch.ia32_xss, true);
+}
+
+static bool kvm_cpuid_has_hyperv(struct kvm_vcpu *vcpu)
+{
+#ifdef CONFIG_KVM_HYPERV
+ struct kvm_cpuid_entry2 *entry;
+
+ entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_INTERFACE);
+ return entry && entry->eax == HYPERV_CPUID_SIGNATURE_EAX;
+#else
+ return false;
+#endif
+}
+
+static bool guest_cpuid_is_amd_or_hygon(struct kvm_vcpu *vcpu)
+{
+ struct kvm_cpuid_entry2 *entry;
+
+ entry = kvm_find_cpuid_entry(vcpu, 0);
+ if (!entry)
+ return false;
+
+ return is_guest_vendor_amd(entry->ebx, entry->ecx, entry->edx) ||
+ is_guest_vendor_hygon(entry->ebx, entry->ecx, entry->edx);
+}
+
+/*
+ * This isn't truly "unsafe", but except for the cpu_caps initialization code,
+ * all register lookups should use __cpuid_entry_get_reg(), which provides
+ * compile-time validation of the input.
+ */
+static u32 cpuid_get_reg_unsafe(struct kvm_cpuid_entry2 *entry, u32 reg)
+{
+ switch (reg) {
+ case CPUID_EAX:
+ return entry->eax;
+ case CPUID_EBX:
+ return entry->ebx;
+ case CPUID_ECX:
+ return entry->ecx;
+ case CPUID_EDX:
+ return entry->edx;
+ default:
+ WARN_ON_ONCE(1);
+ return 0;
+ }
+}
+
+static int cpuid_func_emulated(struct kvm_cpuid_entry2 *entry, u32 func,
+ bool include_partially_emulated);
+
+void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
+{
+ struct kvm_lapic *apic = vcpu->arch.apic;
+ struct kvm_cpuid_entry2 *best;
+ struct kvm_cpuid_entry2 *entry;
+ bool allow_gbpages;
+ int i;
+
+ memset(vcpu->arch.cpu_caps, 0, sizeof(vcpu->arch.cpu_caps));
+ BUILD_BUG_ON(ARRAY_SIZE(reverse_cpuid) != NR_KVM_CPU_CAPS);
+
+ /*
+ * Reset guest capabilities to userspace's guest CPUID definition, i.e.
+ * honor userspace's definition for features that don't require KVM or
+ * hardware management/support (or that KVM simply doesn't care about).
+ */
+ for (i = 0; i < NR_KVM_CPU_CAPS; i++) {
+ const struct cpuid_reg cpuid = reverse_cpuid[i];
+ struct kvm_cpuid_entry2 emulated;
+
+ if (!cpuid.function)
+ continue;
+
+ entry = kvm_find_cpuid_entry_index(vcpu, cpuid.function, cpuid.index);
+ if (!entry)
+ continue;
+
+ cpuid_func_emulated(&emulated, cpuid.function, true);
+
+ /*
+ * A vCPU has a feature if it's supported by KVM and is enabled
+ * in guest CPUID. Note, this includes features that are
+ * supported by KVM but aren't advertised to userspace!
+ */
+ vcpu->arch.cpu_caps[i] = kvm_cpu_caps[i] |
+ cpuid_get_reg_unsafe(&emulated, cpuid.reg);
+ vcpu->arch.cpu_caps[i] &= cpuid_get_reg_unsafe(entry, cpuid.reg);
+ }
+
+ kvm_update_cpuid_runtime(vcpu);
+
+ /*
+ * If TDP is enabled, let the guest use GBPAGES if they're supported in
+ * hardware. The hardware page walker doesn't let KVM disable GBPAGES,
+ * i.e. won't treat them as reserved, and KVM doesn't redo the GVA->GPA
+ * walk for performance and complexity reasons. Not to mention KVM
+ * _can't_ solve the problem because GVA->GPA walks aren't visible to
+ * KVM once a TDP translation is installed. Mimic hardware behavior so
+ * that KVM's is at least consistent, i.e. doesn't randomly inject #PF.
+ * If TDP is disabled, honor *only* guest CPUID as KVM has full control
+ * and can install smaller shadow pages if the host lacks 1GiB support.
+ */
+ allow_gbpages = tdp_enabled ? boot_cpu_has(X86_FEATURE_GBPAGES) :
+ guest_cpu_cap_has(vcpu, X86_FEATURE_GBPAGES);
+ guest_cpu_cap_change(vcpu, X86_FEATURE_GBPAGES, allow_gbpages);
+
+ best = kvm_find_cpuid_entry(vcpu, 1);
+ if (best && apic) {
+ if (cpuid_entry_has(best, X86_FEATURE_TSC_DEADLINE_TIMER))
+ apic->lapic_timer.timer_mode_mask = 3 << 17;
+ else
+ apic->lapic_timer.timer_mode_mask = 1 << 17;
+
+ kvm_apic_set_version(vcpu);
+ }
+
+ vcpu->arch.guest_supported_xcr0 = cpuid_get_supported_xcr0(vcpu);
+ vcpu->arch.guest_supported_xss = cpuid_get_supported_xss(vcpu);
+
+ vcpu->arch.pv_cpuid.features = kvm_apply_cpuid_pv_features_quirk(vcpu);
+
+ vcpu->arch.is_amd_compatible = guest_cpuid_is_amd_or_hygon(vcpu);
+ vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu);
+ vcpu->arch.reserved_gpa_bits = kvm_vcpu_reserved_gpa_bits_raw(vcpu);
+
+ kvm_pmu_refresh(vcpu);
+
+#define __kvm_cpu_cap_has(UNUSED_, f) kvm_cpu_cap_has(f)
+ vcpu->arch.cr4_guest_rsvd_bits = __cr4_reserved_bits(__kvm_cpu_cap_has, UNUSED_) |
+ __cr4_reserved_bits(guest_cpu_cap_has, vcpu);
+#undef __kvm_cpu_cap_has
+
+ kvm_hv_set_cpuid(vcpu, kvm_cpuid_has_hyperv(vcpu));
+
+ /* Invoke the vendor callback only after the above state is updated. */
+ kvm_x86_call(vcpu_after_set_cpuid)(vcpu);
+
+ /*
+ * Except for the MMU, which needs to do its thing any vendor specific
+ * adjustments to the reserved GPA bits.
+ */
+ kvm_mmu_after_set_cpuid(vcpu);
+
+ kvm_make_request(KVM_REQ_RECALC_INTERCEPTS, vcpu);
+}
+
+int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu)
+{
+ struct kvm_cpuid_entry2 *best;
+
+ best = kvm_find_cpuid_entry(vcpu, 0x80000000);
+ if (!best || best->eax < 0x80000008)
+ goto not_found;
+ best = kvm_find_cpuid_entry(vcpu, 0x80000008);
+ if (best)
+ return best->eax & 0xff;
+not_found:
+ return 36;
+}
+
+int cpuid_query_maxguestphyaddr(struct kvm_vcpu *vcpu)
+{
+ struct kvm_cpuid_entry2 *best;
+
+ best = kvm_find_cpuid_entry(vcpu, 0x80000000);
+ if (!best || best->eax < 0x80000008)
+ goto not_found;
+ best = kvm_find_cpuid_entry(vcpu, 0x80000008);
+ if (best)
+ return (best->eax >> 16) & 0xff;
+not_found:
+ return 0;
+}
+
+/*
+ * This "raw" version returns the reserved GPA bits without any adjustments for
+ * encryption technologies that usurp bits. The raw mask should be used if and
+ * only if hardware does _not_ strip the usurped bits, e.g. in virtual MTRRs.
+ */
+u64 kvm_vcpu_reserved_gpa_bits_raw(struct kvm_vcpu *vcpu)
+{
+ return rsvd_bits(cpuid_maxphyaddr(vcpu), 63);
+}
+
+static int kvm_set_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *e2,
+ int nent)
+{
+ u32 vcpu_caps[NR_KVM_CPU_CAPS];
+ int r;
+
+ /*
+ * Apply pending runtime CPUID updates to the current CPUID entries to
+ * avoid false positives due to mismatches on KVM-owned feature flags.
+ */
+ if (vcpu->arch.cpuid_dynamic_bits_dirty)
+ kvm_update_cpuid_runtime(vcpu);
+
+ /*
+ * Swap the existing (old) entries with the incoming (new) entries in
+ * order to massage the new entries, e.g. to account for dynamic bits
+ * that KVM controls, without losing the current guest CPUID, which KVM
+ * needs to preserve in order to unwind on failure.
+ *
+ * Similarly, save the vCPU's current cpu_caps so that the capabilities
+ * can be updated alongside the CPUID entries when performing runtime
+ * updates. Full initialization is done if and only if the vCPU hasn't
+ * run, i.e. only if userspace is potentially changing CPUID features.
+ */
+ swap(vcpu->arch.cpuid_entries, e2);
+ swap(vcpu->arch.cpuid_nent, nent);
+
+ memcpy(vcpu_caps, vcpu->arch.cpu_caps, sizeof(vcpu_caps));
+ BUILD_BUG_ON(sizeof(vcpu_caps) != sizeof(vcpu->arch.cpu_caps));
+
+ /*
+ * KVM does not correctly handle changing guest CPUID after KVM_RUN or
+ * while L2 is active, as MAXPHYADDR, GBPAGES support, AMD reserved bit
+ * behavior, etc. aren't tracked in kvm_mmu_page_role, and L2 state
+ * can't be adjusted (without breaking L2 in some way). As a result,
+ * KVM may reuse SPs/SPTEs and/or run L2 with bad/misconfigured state.
+ *
+ * In practice, no sane VMM mucks with the core vCPU model on the fly.
+ * It would've been better to forbid any KVM_SET_CPUID{,2} calls after
+ * KVM_RUN or KVM_SET_NESTED_STATE altogether, but unfortunately some
+ * VMMs (e.g. QEMU) reuse vCPU fds for CPU hotplug/unplug and do
+ * KVM_SET_CPUID{,2} again. To support this legacy behavior, check
+ * whether the supplied CPUID data is equal to what's already set.
+ */
+ if (!kvm_can_set_cpuid_and_feature_msrs(vcpu)) {
+ r = kvm_cpuid_check_equal(vcpu, e2, nent);
+ if (r)
+ goto err;
+ goto success;
+ }
+
+#ifdef CONFIG_KVM_HYPERV
+ if (kvm_cpuid_has_hyperv(vcpu)) {
+ r = kvm_hv_vcpu_init(vcpu);
+ if (r)
+ goto err;
+ }
+#endif
+
+ r = kvm_check_cpuid(vcpu);
+ if (r)
+ goto err;
+
+#ifdef CONFIG_KVM_XEN
+ vcpu->arch.xen.cpuid = kvm_get_hypervisor_cpuid(vcpu, XEN_SIGNATURE);
+#endif
+ kvm_vcpu_after_set_cpuid(vcpu);
+
+success:
+ kvfree(e2);
+ return 0;
+
+err:
+ memcpy(vcpu->arch.cpu_caps, vcpu_caps, sizeof(vcpu_caps));
+ swap(vcpu->arch.cpuid_entries, e2);
+ swap(vcpu->arch.cpuid_nent, nent);
+ return r;
+}
+
+/* when an old userspace process fills a new kernel module */
+int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
+ struct kvm_cpuid *cpuid,
+ struct kvm_cpuid_entry __user *entries)
+{
+ int r, i;
+ struct kvm_cpuid_entry *e = NULL;
+ struct kvm_cpuid_entry2 *e2 = NULL;
+
+ if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
+ return -E2BIG;
+
+ if (cpuid->nent) {
+ e = vmemdup_array_user(entries, cpuid->nent, sizeof(*e));
+ if (IS_ERR(e))
+ return PTR_ERR(e);
+
+ e2 = kvmalloc_objs(*e2, cpuid->nent, GFP_KERNEL_ACCOUNT);
+ if (!e2) {
+ r = -ENOMEM;
+ goto out_free_cpuid;
+ }
+ }
+ for (i = 0; i < cpuid->nent; i++) {
+ e2[i].function = e[i].function;
+ e2[i].eax = e[i].eax;
+ e2[i].ebx = e[i].ebx;
+ e2[i].ecx = e[i].ecx;
+ e2[i].edx = e[i].edx;
+ e2[i].index = 0;
+ e2[i].flags = 0;
+ e2[i].padding[0] = 0;
+ e2[i].padding[1] = 0;
+ e2[i].padding[2] = 0;
+ }
+
+ r = kvm_set_cpuid(vcpu, e2, cpuid->nent);
+ if (r)
+ kvfree(e2);
+
+out_free_cpuid:
+ kvfree(e);
+
+ return r;
+}
+
+int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
+ struct kvm_cpuid2 *cpuid,
+ struct kvm_cpuid_entry2 __user *entries)
+{
+ struct kvm_cpuid_entry2 *e2 = NULL;
+ int r;
+
+ if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
+ return -E2BIG;
+
+ if (cpuid->nent) {
+ e2 = vmemdup_array_user(entries, cpuid->nent, sizeof(*e2));
+ if (IS_ERR(e2))
+ return PTR_ERR(e2);
+ }
+
+ r = kvm_set_cpuid(vcpu, e2, cpuid->nent);
+ if (r)
+ kvfree(e2);
+
+ return r;
+}
+
+int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
+ struct kvm_cpuid2 *cpuid,
+ struct kvm_cpuid_entry2 __user *entries)
+{
+ if (cpuid->nent < vcpu->arch.cpuid_nent)
+ return -E2BIG;
+
+ if (vcpu->arch.cpuid_dynamic_bits_dirty)
+ kvm_update_cpuid_runtime(vcpu);
+
+ if (copy_to_user(entries, vcpu->arch.cpuid_entries,
+ vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2)))
+ return -EFAULT;
+
+ cpuid->nent = vcpu->arch.cpuid_nent;
+ return 0;
+}
+
+static __always_inline u32 raw_cpuid_get(struct cpuid_reg cpuid)
+{
+ struct kvm_cpuid_entry2 entry;
+ u32 base;
+
+ /*
+ * KVM only supports features defined by Intel (0x0), AMD (0x80000000),
+ * and Centaur (0xc0000000). WARN if a feature for new vendor base is
+ * defined, as this and other code would need to be updated.
+ */
+ base = cpuid.function & 0xffff0000;
+ if (WARN_ON_ONCE(base && base != 0x80000000 && base != 0xc0000000))
+ return 0;
+
+ if (cpuid_eax(base) < cpuid.function)
+ return 0;
+
+ cpuid_count(cpuid.function, cpuid.index,
+ &entry.eax, &entry.ebx, &entry.ecx, &entry.edx);
+
+ return *__cpuid_entry_get_reg(&entry, cpuid.reg);
+}
+
+/*
+ * For kernel-defined leafs, mask KVM's supported feature set with the kernel's
+ * capabilities as well as raw CPUID. For KVM-defined leafs, consult only raw
+ * CPUID, as KVM is the one and only authority (in the kernel).
+ */
+#define kvm_cpu_cap_init(leaf, feature_initializers...) \
+do { \
+ const struct cpuid_reg cpuid = x86_feature_cpuid(leaf * 32); \
+ const u32 __maybe_unused kvm_cpu_cap_init_in_progress = leaf; \
+ const u32 *kernel_cpu_caps = boot_cpu_data.x86_capability; \
+ u32 kvm_cpu_cap_passthrough = 0; \
+ u32 kvm_cpu_cap_synthesized = 0; \
+ u32 kvm_cpu_cap_emulated = 0; \
+ u32 kvm_cpu_cap_features = 0; \
+ \
+ feature_initializers \
+ \
+ kvm_cpu_caps[leaf] = kvm_cpu_cap_features; \
+ \
+ if (leaf < NCAPINTS) \
+ kvm_cpu_caps[leaf] &= kernel_cpu_caps[leaf]; \
+ \
+ kvm_cpu_caps[leaf] |= kvm_cpu_cap_passthrough; \
+ kvm_cpu_caps[leaf] &= (raw_cpuid_get(cpuid) | \
+ kvm_cpu_cap_synthesized); \
+ kvm_cpu_caps[leaf] |= kvm_cpu_cap_emulated; \
+} while (0)
+
+/*
+ * Assert that the feature bit being declared, e.g. via F(), is in the CPUID
+ * word that's being initialized. Exempt 0x8000_0001.EDX usage of 0x1.EDX
+ * features, as AMD duplicated many 0x1.EDX features into 0x8000_0001.EDX.
+ */
+#define KVM_VALIDATE_CPU_CAP_USAGE(name) \
+do { \
+ u32 __leaf = __feature_leaf(X86_FEATURE_##name); \
+ \
+ BUILD_BUG_ON(__leaf != kvm_cpu_cap_init_in_progress); \
+} while (0)
+
+#define F(name) \
+({ \
+ KVM_VALIDATE_CPU_CAP_USAGE(name); \
+ kvm_cpu_cap_features |= feature_bit(name); \
+})
+
+/* Scattered Flag - For features that are scattered by cpufeatures.h. */
+#define SCATTERED_F(name) \
+({ \
+ BUILD_BUG_ON(X86_FEATURE_##name >= MAX_CPU_FEATURES); \
+ KVM_VALIDATE_CPU_CAP_USAGE(name); \
+ if (boot_cpu_has(X86_FEATURE_##name)) \
+ F(name); \
+})
+
+/* Features that KVM supports only on 64-bit kernels. */
+#define X86_64_F(name) \
+({ \
+ KVM_VALIDATE_CPU_CAP_USAGE(name); \
+ if (IS_ENABLED(CONFIG_X86_64)) \
+ F(name); \
+})
+
+/*
+ * Emulated Feature - For features that KVM emulates in software irrespective
+ * of host CPU/kernel support.
+ */
+#define EMULATED_F(name) \
+({ \
+ kvm_cpu_cap_emulated |= feature_bit(name); \
+ F(name); \
+})
+
+/*
+ * Synthesized Feature - For features that are synthesized into boot_cpu_data,
+ * i.e. may not be present in the raw CPUID, but can still be advertised to
+ * userspace. Primarily used for mitigation related feature flags.
+ */
+#define SYNTHESIZED_F(name) \
+({ \
+ kvm_cpu_cap_synthesized |= feature_bit(name); \
+ \
+ BUILD_BUG_ON(X86_FEATURE_##name >= MAX_CPU_FEATURES); \
+ if (boot_cpu_has(X86_FEATURE_##name)) \
+ F(name); \
+})
+
+/*
+ * Passthrough Feature - For features that KVM supports based purely on raw
+ * hardware CPUID, i.e. that KVM virtualizes even if the host kernel doesn't
+ * use the feature. Simply force set the feature in KVM's capabilities, raw
+ * CPUID support will be factored in by kvm_cpu_cap_mask().
+ */
+#define PASSTHROUGH_F(name) \
+({ \
+ kvm_cpu_cap_passthrough |= feature_bit(name); \
+ F(name); \
+})
+
+/*
+ * Aliased Features - For features in 0x8000_0001.EDX that are duplicates of
+ * identical 0x1.EDX features, and thus are aliased from 0x1 to 0x8000_0001.
+ */
+#define ALIASED_1_EDX_F(name) \
+({ \
+ BUILD_BUG_ON(__feature_leaf(X86_FEATURE_##name) != CPUID_1_EDX); \
+ BUILD_BUG_ON(kvm_cpu_cap_init_in_progress != CPUID_8000_0001_EDX); \
+ kvm_cpu_cap_features |= feature_bit(name); \
+})
+
+/*
+ * Vendor Features - For features that KVM supports, but are added in later
+ * because they require additional vendor enabling.
+ */
+#define VENDOR_F(name) \
+({ \
+ KVM_VALIDATE_CPU_CAP_USAGE(name); \
+})
+
+/*
+ * Runtime Features - For features that KVM dynamically sets/clears at runtime,
+ * e.g. when CR4 changes, but which are never advertised to userspace.
+ */
+#define RUNTIME_F(name) \
+({ \
+ KVM_VALIDATE_CPU_CAP_USAGE(name); \
+})
+
+/*
+ * Undefine the MSR bit macro to avoid token concatenation issues when
+ * processing X86_FEATURE_SPEC_CTRL_SSBD.
+ */
+#undef SPEC_CTRL_SSBD
+
+/* DS is defined by ptrace-abi.h on 32-bit builds. */
+#undef DS
+
+void kvm_initialize_cpu_caps(void)
+{
+ memset(kvm_cpu_caps, 0, sizeof(kvm_cpu_caps));
+
+ WARN_ON_ONCE(kvm_is_configuring_cpu_caps);
+ kvm_is_configuring_cpu_caps = true;
+
+ BUILD_BUG_ON(sizeof(kvm_cpu_caps) - (NKVMCAPINTS * sizeof(*kvm_cpu_caps)) >
+ sizeof(boot_cpu_data.x86_capability));
+
+ kvm_cpu_cap_init(CPUID_1_ECX,
+ F(XMM3),
+ F(PCLMULQDQ),
+ VENDOR_F(DTES64),
+ /*
+ * NOTE: MONITOR (and MWAIT) are emulated as NOP, but *not*
+ * advertised to guests via CPUID! MWAIT is also technically a
+ * runtime flag thanks to IA32_MISC_ENABLES; mark it as such so
+ * that KVM is aware that it's a known, unadvertised flag.
+ */
+ RUNTIME_F(MWAIT),
+ /* DS-CPL */
+ VENDOR_F(VMX),
+ /* SMX, EST */
+ /* TM2 */
+ F(SSSE3),
+ /* CNXT-ID */
+ /* Reserved */
+ F(FMA),
+ F(CX16),
+ /* xTPR Update */
+ F(PDCM),
+ F(PCID),
+ /* Reserved, DCA */
+ F(XMM4_1),
+ F(XMM4_2),
+ EMULATED_F(X2APIC),
+ F(MOVBE),
+ F(POPCNT),
+ EMULATED_F(TSC_DEADLINE_TIMER),
+ F(AES),
+ F(XSAVE),
+ RUNTIME_F(OSXSAVE),
+ F(AVX),
+ F(F16C),
+ F(RDRAND),
+ EMULATED_F(HYPERVISOR),
+ );
+
+ kvm_cpu_cap_init(CPUID_1_EDX,
+ F(FPU),
+ F(VME),
+ F(DE),
+ F(PSE),
+ F(TSC),
+ F(MSR),
+ F(PAE),
+ F(MCE),
+ F(CX8),
+ F(APIC),
+ /* Reserved */
+ F(SEP),
+ F(MTRR),
+ F(PGE),
+ F(MCA),
+ F(CMOV),
+ F(PAT),
+ F(PSE36),
+ /* PSN */
+ F(CLFLUSH),
+ /* Reserved */
+ VENDOR_F(DS),
+ /* ACPI */
+ F(MMX),
+ F(FXSR),
+ F(XMM),
+ F(XMM2),
+ F(SELFSNOOP),
+ /* HTT, TM, Reserved, PBE */
+ );
+
+ kvm_cpu_cap_init(CPUID_7_0_EBX,
+ F(FSGSBASE),
+ EMULATED_F(TSC_ADJUST),
+ F(SGX),
+ F(BMI1),
+ F(HLE),
+ F(AVX2),
+ F(FDP_EXCPTN_ONLY),
+ F(SMEP),
+ F(BMI2),
+ F(ERMS),
+ F(INVPCID),
+ F(RTM),
+ F(ZERO_FCS_FDS),
+ VENDOR_F(MPX),
+ F(AVX512F),
+ F(AVX512DQ),
+ F(RDSEED),
+ F(ADX),
+ F(SMAP),
+ F(AVX512IFMA),
+ F(CLFLUSHOPT),
+ F(CLWB),
+ VENDOR_F(INTEL_PT),
+ F(AVX512PF),
+ F(AVX512ER),
+ F(AVX512CD),
+ F(SHA_NI),
+ F(AVX512BW),
+ F(AVX512VL),
+ );
+
+ kvm_cpu_cap_init(CPUID_7_ECX,
+ F(AVX512VBMI),
+ PASSTHROUGH_F(LA57),
+ F(PKU),
+ RUNTIME_F(OSPKE),
+ F(RDPID),
+ F(AVX512_VPOPCNTDQ),
+ F(UMIP),
+ F(AVX512_VBMI2),
+ F(GFNI),
+ F(VAES),
+ F(VPCLMULQDQ),
+ F(AVX512_VNNI),
+ F(AVX512_BITALG),
+ F(CLDEMOTE),
+ F(MOVDIRI),
+ F(MOVDIR64B),
+ VENDOR_F(WAITPKG),
+ F(SGX_LC),
+ F(BUS_LOCK_DETECT),
+ X86_64_F(SHSTK),
+ );
+
+ /*
+ * PKU not yet implemented for shadow paging and requires OSPKE
+ * to be set on the host. Clear it if that is not the case
+ */
+ if (!tdp_enabled || !boot_cpu_has(X86_FEATURE_OSPKE))
+ kvm_cpu_cap_clear(X86_FEATURE_PKU);
+
+ /*
+ * Shadow Stacks aren't implemented in the Shadow MMU. Shadow Stack
+ * accesses require "magic" Writable=0,Dirty=1 protection, which KVM
+ * doesn't know how to emulate or map.
+ */
+ if (!tdp_enabled)
+ kvm_cpu_cap_clear(X86_FEATURE_SHSTK);
+
+ kvm_cpu_cap_init(CPUID_7_EDX,
+ F(AVX512_4VNNIW),
+ F(AVX512_4FMAPS),
+ F(SPEC_CTRL),
+ F(SPEC_CTRL_SSBD),
+ EMULATED_F(ARCH_CAPABILITIES),
+ F(INTEL_STIBP),
+ F(MD_CLEAR),
+ F(AVX512_VP2INTERSECT),
+ F(FSRM),
+ F(SERIALIZE),
+ F(TSXLDTRK),
+ F(AVX512_FP16),
+ F(AMX_TILE),
+ F(AMX_INT8),
+ F(AMX_BF16),
+ F(FLUSH_L1D),
+ F(IBT),
+ );
+
+ /*
+ * Disable support for IBT and SHSTK if KVM is configured to emulate
+ * accesses to reserved GPAs, as KVM's emulator doesn't support IBT or
+ * SHSTK, nor does KVM handle Shadow Stack #PFs (see above).
+ */
+ if (allow_smaller_maxphyaddr) {
+ kvm_cpu_cap_clear(X86_FEATURE_SHSTK);
+ kvm_cpu_cap_clear(X86_FEATURE_IBT);
+ }
+
+ if (boot_cpu_has(X86_FEATURE_AMD_IBPB_RET) &&
+ boot_cpu_has(X86_FEATURE_AMD_IBPB) &&
+ boot_cpu_has(X86_FEATURE_AMD_IBRS))
+ kvm_cpu_cap_set(X86_FEATURE_SPEC_CTRL);
+ if (boot_cpu_has(X86_FEATURE_STIBP))
+ kvm_cpu_cap_set(X86_FEATURE_INTEL_STIBP);
+ if (boot_cpu_has(X86_FEATURE_AMD_SSBD))
+ kvm_cpu_cap_set(X86_FEATURE_SPEC_CTRL_SSBD);
+
+ kvm_cpu_cap_init(CPUID_7_1_EAX,
+ F(SHA512),
+ F(SM3),
+ F(SM4),
+ F(AVX_VNNI),
+ F(AVX512_BF16),
+ F(CMPCCXADD),
+ F(FZRM),
+ F(FSRS),
+ F(FSRC),
+ F(WRMSRNS),
+ X86_64_F(LKGS),
+ F(AMX_FP16),
+ F(AVX_IFMA),
+ F(LAM),
+ F(MOVRS),
+ );
+
+ kvm_cpu_cap_init(CPUID_7_1_ECX,
+ SCATTERED_F(MSR_IMM),
+ );
+
+ kvm_cpu_cap_init(CPUID_7_1_EDX,
+ F(AVX_VNNI_INT8),
+ F(AVX_NE_CONVERT),
+ F(AMX_COMPLEX),
+ F(AVX_VNNI_INT16),
+ F(PREFETCHITI),
+ F(AVX10),
+ );
+
+ kvm_cpu_cap_init(CPUID_7_2_EDX,
+ F(INTEL_PSFD),
+ F(IPRED_CTRL),
+ F(RRSBA_CTRL),
+ F(DDPD_U),
+ F(BHI_CTRL),
+ F(MCDT_NO),
+ );
+
+ kvm_cpu_cap_init(CPUID_D_1_EAX,
+ F(XSAVEOPT),
+ F(XSAVEC),
+ F(XGETBV1),
+ F(XSAVES),
+ X86_64_F(XFD),
+ );
+
+ kvm_cpu_cap_init(CPUID_12_EAX,
+ SCATTERED_F(SGX1),
+ SCATTERED_F(SGX2),
+ SCATTERED_F(SGX_EDECCSSA),
+ );
+
+ kvm_cpu_cap_init(CPUID_1E_1_EAX,
+ F(AMX_INT8_ALIAS),
+ F(AMX_BF16_ALIAS),
+ F(AMX_COMPLEX_ALIAS),
+ F(AMX_FP16_ALIAS),
+ F(AMX_FP8),
+ F(AMX_TF32),
+ F(AMX_AVX512),
+ F(AMX_MOVRS),
+ );
+
+ kvm_cpu_cap_init(CPUID_24_0_EBX,
+ F(AVX10_128),
+ F(AVX10_256),
+ F(AVX10_512),
+ );
+
+ kvm_cpu_cap_init(CPUID_24_1_ECX,
+ F(AVX10_VNNI_INT),
+ );
+
+ kvm_cpu_cap_init(CPUID_8000_0001_ECX,
+ F(LAHF_LM),
+ F(CMP_LEGACY),
+ VENDOR_F(SVM),
+ /* ExtApicSpace */
+ F(CR8_LEGACY),
+ F(ABM),
+ F(SSE4A),
+ F(MISALIGNSSE),
+ F(3DNOWPREFETCH),
+ F(OSVW),
+ /* IBS */
+ F(XOP),
+ /* SKINIT, WDT, LWP */
+ F(FMA4),
+ F(TBM),
+ F(TOPOEXT),
+ VENDOR_F(PERFCTR_CORE),
+ );
+
+ kvm_cpu_cap_init(CPUID_8000_0001_EDX,
+ ALIASED_1_EDX_F(FPU),
+ ALIASED_1_EDX_F(VME),
+ ALIASED_1_EDX_F(DE),
+ ALIASED_1_EDX_F(PSE),
+ ALIASED_1_EDX_F(TSC),
+ ALIASED_1_EDX_F(MSR),
+ ALIASED_1_EDX_F(PAE),
+ ALIASED_1_EDX_F(MCE),
+ ALIASED_1_EDX_F(CX8),
+ ALIASED_1_EDX_F(APIC),
+ /* Reserved */
+ F(SYSCALL),
+ ALIASED_1_EDX_F(MTRR),
+ ALIASED_1_EDX_F(PGE),
+ ALIASED_1_EDX_F(MCA),
+ ALIASED_1_EDX_F(CMOV),
+ ALIASED_1_EDX_F(PAT),
+ ALIASED_1_EDX_F(PSE36),
+ /* Reserved */
+ F(NX),
+ /* Reserved */
+ F(MMXEXT),
+ ALIASED_1_EDX_F(MMX),
+ ALIASED_1_EDX_F(FXSR),
+ F(FXSR_OPT),
+ X86_64_F(GBPAGES),
+ F(RDTSCP),
+ /* Reserved */
+ X86_64_F(LM),
+ F(3DNOWEXT),
+ F(3DNOW),
+ );
+
+ if (!tdp_enabled && IS_ENABLED(CONFIG_X86_64))
+ kvm_cpu_cap_set(X86_FEATURE_GBPAGES);
+
+ kvm_cpu_cap_init(CPUID_8000_0007_EDX,
+ SCATTERED_F(CONSTANT_TSC),
+ );
+
+ kvm_cpu_cap_init(CPUID_8000_0008_EBX,
+ F(CLZERO),
+ F(XSAVEERPTR),
+ F(WBNOINVD),
+ F(AMD_IBPB),
+ F(AMD_IBRS),
+ F(AMD_SSBD),
+ F(VIRT_SSBD),
+ F(AMD_SSB_NO),
+ F(AMD_STIBP),
+ F(AMD_STIBP_ALWAYS_ON),
+ F(AMD_IBRS_SAME_MODE),
+ PASSTHROUGH_F(EFER_LMSLE_MBZ),
+ F(AMD_PSFD),
+ F(AMD_IBPB_RET),
+ );
+
+ /*
+ * AMD has separate bits for each SPEC_CTRL bit.
+ * arch/x86/kernel/cpu/bugs.c is kind enough to
+ * record that in cpufeatures so use them.
+ */
+ if (boot_cpu_has(X86_FEATURE_IBPB)) {
+ kvm_cpu_cap_set(X86_FEATURE_AMD_IBPB);
+ if (boot_cpu_has(X86_FEATURE_SPEC_CTRL) &&
+ !boot_cpu_has_bug(X86_BUG_EIBRS_PBRSB))
+ kvm_cpu_cap_set(X86_FEATURE_AMD_IBPB_RET);
+ }
+ if (boot_cpu_has(X86_FEATURE_IBRS))
+ kvm_cpu_cap_set(X86_FEATURE_AMD_IBRS);
+ if (boot_cpu_has(X86_FEATURE_STIBP))
+ kvm_cpu_cap_set(X86_FEATURE_AMD_STIBP);
+ if (boot_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD))
+ kvm_cpu_cap_set(X86_FEATURE_AMD_SSBD);
+ if (!boot_cpu_has_bug(X86_BUG_SPEC_STORE_BYPASS))
+ kvm_cpu_cap_set(X86_FEATURE_AMD_SSB_NO);
+ /*
+ * The preference is to use SPEC CTRL MSR instead of the
+ * VIRT_SPEC MSR.
+ */
+ if (boot_cpu_has(X86_FEATURE_LS_CFG_SSBD) &&
+ !boot_cpu_has(X86_FEATURE_AMD_SSBD))
+ kvm_cpu_cap_set(X86_FEATURE_VIRT_SSBD);
+
+ /* All SVM features required additional vendor module enabling. */
+ kvm_cpu_cap_init(CPUID_8000_000A_EDX,
+ VENDOR_F(NPT),
+ VENDOR_F(VMCBCLEAN),
+ VENDOR_F(FLUSHBYASID),
+ VENDOR_F(NRIPS),
+ VENDOR_F(TSCRATEMSR),
+ VENDOR_F(V_VMSAVE_VMLOAD),
+ VENDOR_F(LBRV),
+ VENDOR_F(PAUSEFILTER),
+ VENDOR_F(PFTHRESHOLD),
+ VENDOR_F(VGIF),
+ VENDOR_F(VNMI),
+ VENDOR_F(SVME_ADDR_CHK),
+ );
+
+ kvm_cpu_cap_init(CPUID_8000_001F_EAX,
+ VENDOR_F(SME),
+ VENDOR_F(SEV),
+ /* VM_PAGE_FLUSH */
+ VENDOR_F(SEV_ES),
+ F(SME_COHERENT),
+ );
+
+ kvm_cpu_cap_init(CPUID_8000_0021_EAX,
+ F(NO_NESTED_DATA_BP),
+ F(WRMSR_XX_BASE_NS),
+ /*
+ * Synthesize "LFENCE is serializing" into the AMD-defined entry
+ * in KVM's supported CPUID, i.e. if the feature is reported as
+ * supported by the kernel. LFENCE_RDTSC was a Linux-defined
+ * synthetic feature long before AMD joined the bandwagon, e.g.
+ * LFENCE is serializing on most CPUs that support SSE2. On
+ * CPUs that don't support AMD's leaf, ANDing with the raw host
+ * CPUID will drop the flags, and reporting support in AMD's
+ * leaf can make it easier for userspace to detect the feature.
+ */
+ SYNTHESIZED_F(LFENCE_RDTSC),
+ /* SmmPgCfgLock */
+ /* 4: Resv */
+ SYNTHESIZED_F(VERW_CLEAR),
+ F(NULL_SEL_CLR_BASE),
+ /* UpperAddressIgnore */
+ F(AUTOIBRS),
+ EMULATED_F(NO_SMM_CTL_MSR),
+ /* PrefetchCtlMsr */
+ EMULATED_F(GP_ON_USER_CPUID),
+ /* EPSF */
+ F(PREFETCHI),
+ F(AVX512_BMM),
+ F(ERAPS),
+ SYNTHESIZED_F(SBPB),
+ SYNTHESIZED_F(IBPB_BRTYPE),
+ SYNTHESIZED_F(SRSO_NO),
+ F(SRSO_USER_KERNEL_NO),
+ );
+
+ kvm_cpu_cap_init(CPUID_8000_0021_ECX,
+ SYNTHESIZED_F(TSA_SQ_NO),
+ SYNTHESIZED_F(TSA_L1_NO),
+ );
+
+ kvm_cpu_cap_init(CPUID_8000_0022_EAX,
+ F(PERFMON_V2),
+ );
+
+ if (!static_cpu_has_bug(X86_BUG_NULL_SEG))
+ kvm_cpu_cap_set(X86_FEATURE_NULL_SEL_CLR_BASE);
+
+ kvm_cpu_cap_init(CPUID_C000_0001_EDX,
+ F(XSTORE),
+ F(XSTORE_EN),
+ F(XCRYPT),
+ F(XCRYPT_EN),
+ F(ACE2),
+ F(ACE2_EN),
+ F(PHE),
+ F(PHE_EN),
+ F(PMM),
+ F(PMM_EN),
+ );
+
+ /*
+ * Hide RDTSCP and RDPID if either feature is reported as supported but
+ * probing MSR_TSC_AUX failed. This is purely a sanity check and
+ * should never happen, but the guest will likely crash if RDTSCP or
+ * RDPID is misreported, and KVM has botched MSR_TSC_AUX emulation in
+ * the past. For example, the sanity check may fire if this instance of
+ * KVM is running as L1 on top of an older, broken KVM.
+ */
+ if (WARN_ON((kvm_cpu_cap_has(X86_FEATURE_RDTSCP) ||
+ kvm_cpu_cap_has(X86_FEATURE_RDPID)) &&
+ !kvm_is_supported_user_return_msr(MSR_TSC_AUX))) {
+ kvm_cpu_cap_clear(X86_FEATURE_RDTSCP);
+ kvm_cpu_cap_clear(X86_FEATURE_RDPID);
+ }
+}
+EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_initialize_cpu_caps);
+
+#undef F
+#undef SCATTERED_F
+#undef X86_64_F
+#undef EMULATED_F
+#undef SYNTHESIZED_F
+#undef PASSTHROUGH_F
+#undef ALIASED_1_EDX_F
+#undef VENDOR_F
+#undef RUNTIME_F
+
+struct kvm_cpuid_array {
+ struct kvm_cpuid_entry2 *entries;
+ int maxnent;
+ int nent;
+};
+
+static struct kvm_cpuid_entry2 *get_next_cpuid(struct kvm_cpuid_array *array)
+{
+ if (array->nent >= array->maxnent)
+ return NULL;
+
+ return &array->entries[array->nent++];
+}
+
+static struct kvm_cpuid_entry2 *do_host_cpuid(struct kvm_cpuid_array *array,
+ u32 function, u32 index)
+{
+ struct kvm_cpuid_entry2 *entry = get_next_cpuid(array);
+
+ if (!entry)
+ return NULL;
+
+ memset(entry, 0, sizeof(*entry));
+ entry->function = function;
+ entry->index = index;
+ switch (function & 0xC0000000) {
+ case 0x40000000:
+ /* Hypervisor leaves are always synthesized by __do_cpuid_func. */
+ return entry;
+
+ case 0x80000000:
+ /*
+ * 0x80000021 is sometimes synthesized by __do_cpuid_func, which
+ * would result in out-of-bounds calls to do_host_cpuid.
+ */
+ {
+ static int max_cpuid_80000000;
+ if (!READ_ONCE(max_cpuid_80000000))
+ WRITE_ONCE(max_cpuid_80000000, cpuid_eax(0x80000000));
+ if (function > READ_ONCE(max_cpuid_80000000))
+ return entry;
+ }
+ break;
+
+ default:
+ break;
+ }
+
+ cpuid_count(entry->function, entry->index,
+ &entry->eax, &entry->ebx, &entry->ecx, &entry->edx);
+
+ if (cpuid_function_is_indexed(function))
+ entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+
+ return entry;
+}
+
+static int cpuid_func_emulated(struct kvm_cpuid_entry2 *entry, u32 func,
+ bool include_partially_emulated)
+{
+ memset(entry, 0, sizeof(*entry));
+
+ entry->function = func;
+ entry->index = 0;
+ entry->flags = 0;
+
+ switch (func) {
+ case 0:
+ entry->eax = 7;
+ return 1;
+ case 1:
+ entry->ecx = feature_bit(MOVBE);
+ /*
+ * KVM allows userspace to enumerate MONITOR+MWAIT support to
+ * the guest, but the MWAIT feature flag is never advertised
+ * to userspace because MONITOR+MWAIT aren't virtualized by
+ * hardware, can't be faithfully emulated in software (KVM
+ * emulates them as NOPs), and allowing the guest to execute
+ * them natively requires enabling a per-VM capability.
+ */
+ if (include_partially_emulated)
+ entry->ecx |= feature_bit(MWAIT);
+ return 1;
+ case 7:
+ entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+ entry->eax = 0;
+ if (kvm_cpu_cap_has(X86_FEATURE_RDTSCP))
+ entry->ecx = feature_bit(RDPID);
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+static int __do_cpuid_func_emulated(struct kvm_cpuid_array *array, u32 func)
+{
+ if (array->nent >= array->maxnent)
+ return -E2BIG;
+
+ array->nent += cpuid_func_emulated(&array->entries[array->nent], func, false);
+ return 0;
+}
+
+static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
+{
+ struct kvm_cpuid_entry2 *entry;
+ int r, i, max_idx;
+
+ /* all calls to cpuid_count() should be made on the same cpu */
+ get_cpu();
+
+ r = -E2BIG;
+
+ entry = do_host_cpuid(array, function, 0);
+ if (!entry)
+ goto out;
+
+ switch (function) {
+ case 0:
+ /* Limited to the highest leaf implemented in KVM. */
+ entry->eax = min(entry->eax, 0x24U);
+ break;
+ case 1:
+ cpuid_entry_override(entry, CPUID_1_EDX);
+ cpuid_entry_override(entry, CPUID_1_ECX);
+ break;
+ case 2:
+ /*
+ * On ancient CPUs, function 2 entries are STATEFUL. That is,
+ * CPUID(function=2, index=0) may return different results each
+ * time, with the least-significant byte in EAX enumerating the
+ * number of times software should do CPUID(2, 0).
+ *
+ * Modern CPUs, i.e. every CPU KVM has *ever* run on are less
+ * idiotic. Intel's SDM states that EAX & 0xff "will always
+ * return 01H. Software should ignore this value and not
+ * interpret it as an informational descriptor", while AMD's
+ * APM states that CPUID(2) is reserved.
+ *
+ * WARN if a frankenstein CPU that supports virtualization and
+ * a stateful CPUID.0x2 is encountered.
+ */
+ WARN_ON_ONCE((entry->eax & 0xff) > 1);
+ break;
+ /* functions 4 and 0x8000001d have additional index. */
+ case 4:
+ case 0x8000001d:
+ /*
+ * Read entries until the cache type in the previous entry is
+ * zero, i.e. indicates an invalid entry.
+ */
+ for (i = 1; entry->eax & 0x1f; ++i) {
+ entry = do_host_cpuid(array, function, i);
+ if (!entry)
+ goto out;
+ }
+ break;
+ case 6: /* Thermal management */
+ entry->eax = 0x4; /* allow ARAT */
+ entry->ebx = 0;
+ entry->ecx = 0;
+ entry->edx = 0;
+ break;
+ /* function 7 has additional index. */
+ case 7:
+ max_idx = entry->eax = min(entry->eax, 2u);
+ cpuid_entry_override(entry, CPUID_7_0_EBX);
+ cpuid_entry_override(entry, CPUID_7_ECX);
+ cpuid_entry_override(entry, CPUID_7_EDX);
+
+ /* KVM only supports up to 0x7.2, capped above via min(). */
+ if (max_idx >= 1) {
+ entry = do_host_cpuid(array, function, 1);
+ if (!entry)
+ goto out;
+
+ cpuid_entry_override(entry, CPUID_7_1_EAX);
+ cpuid_entry_override(entry, CPUID_7_1_ECX);
+ cpuid_entry_override(entry, CPUID_7_1_EDX);
+ entry->ebx = 0;
+ }
+ if (max_idx >= 2) {
+ entry = do_host_cpuid(array, function, 2);
+ if (!entry)
+ goto out;
+
+ cpuid_entry_override(entry, CPUID_7_2_EDX);
+ entry->ecx = 0;
+ entry->ebx = 0;
+ entry->eax = 0;
+ }
+ break;
+ case 0xa: { /* Architectural Performance Monitoring */
+ union cpuid10_eax eax = { };
+ union cpuid10_edx edx = { };
+
+ if (!enable_pmu || !cpu_feature_enabled(X86_FEATURE_ARCH_PERFMON)) {
+ entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
+ break;
+ }
+
+ eax.split.version_id = kvm_pmu_cap.version;
+ eax.split.num_counters = kvm_pmu_cap.num_counters_gp;
+ eax.split.bit_width = kvm_pmu_cap.bit_width_gp;
+ eax.split.mask_length = kvm_pmu_cap.events_mask_len;
+ edx.split.num_counters_fixed = kvm_pmu_cap.num_counters_fixed;
+ edx.split.bit_width_fixed = kvm_pmu_cap.bit_width_fixed;
+
+ if (kvm_pmu_cap.version)
+ edx.split.anythread_deprecated = 1;
+
+ entry->eax = eax.full;
+ entry->ebx = kvm_pmu_cap.events_mask;
+ entry->ecx = 0;
+ entry->edx = edx.full;
+ break;
+ }
+ case 0x1f:
+ case 0xb:
+ /*
+ * No topology; a valid topology is indicated by the presence
+ * of subleaf 1.
+ */
+ entry->eax = entry->ebx = entry->ecx = 0;
+ break;
+ case 0xd: {
+ u64 permitted_xcr0 = kvm_get_filtered_xcr0();
+ u64 permitted_xss = kvm_caps.supported_xss;
+
+ entry->eax &= permitted_xcr0;
+ entry->ebx = xstate_required_size(permitted_xcr0, false);
+ entry->ecx = entry->ebx;
+ entry->edx &= permitted_xcr0 >> 32;
+ if (!permitted_xcr0)
+ break;
+
+ entry = do_host_cpuid(array, function, 1);
+ if (!entry)
+ goto out;
+
+ cpuid_entry_override(entry, CPUID_D_1_EAX);
+ if (entry->eax & (feature_bit(XSAVES) | feature_bit(XSAVEC)))
+ entry->ebx = xstate_required_size(permitted_xcr0 | permitted_xss,
+ true);
+ else {
+ WARN_ON_ONCE(permitted_xss != 0);
+ entry->ebx = 0;
+ }
+ entry->ecx &= permitted_xss;
+ entry->edx &= permitted_xss >> 32;
+
+ for (i = 2; i < 64; ++i) {
+ bool s_state;
+ if (permitted_xcr0 & BIT_ULL(i))
+ s_state = false;
+ else if (permitted_xss & BIT_ULL(i))
+ s_state = true;
+ else
+ continue;
+
+ entry = do_host_cpuid(array, function, i);
+ if (!entry)
+ goto out;
+
+ /*
+ * The supported check above should have filtered out
+ * invalid sub-leafs. Only valid sub-leafs should
+ * reach this point, and they should have a non-zero
+ * save state size. Furthermore, check whether the
+ * processor agrees with permitted_xcr0/permitted_xss
+ * on whether this is an XCR0- or IA32_XSS-managed area.
+ */
+ if (WARN_ON_ONCE(!entry->eax || (entry->ecx & 0x1) != s_state)) {
+ --array->nent;
+ continue;
+ }
+
+ if (!kvm_cpu_cap_has(X86_FEATURE_XFD))
+ entry->ecx &= ~BIT_ULL(2);
+ entry->edx = 0;
+ }
+ break;
+ }
+ case 0x12:
+ /* Intel SGX */
+ if (!kvm_cpu_cap_has(X86_FEATURE_SGX)) {
+ entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
+ break;
+ }
+
+ /*
+ * Index 0: Sub-features, MISCSELECT (a.k.a extended features)
+ * and max enclave sizes. The SGX sub-features and MISCSELECT
+ * are restricted by kernel and KVM capabilities (like most
+ * feature flags), while enclave size is unrestricted.
+ */
+ cpuid_entry_override(entry, CPUID_12_EAX);
+ entry->ebx &= SGX_MISC_EXINFO;
+
+ entry = do_host_cpuid(array, function, 1);
+ if (!entry)
+ goto out;
+
+ /*
+ * Index 1: SECS.ATTRIBUTES. ATTRIBUTES are restricted a la
+ * feature flags. Advertise all supported flags, including
+ * privileged attributes that require explicit opt-in from
+ * userspace. ATTRIBUTES.XFRM is not adjusted as userspace is
+ * expected to derive it from supported XCR0.
+ */
+ entry->eax &= SGX_ATTR_PRIV_MASK | SGX_ATTR_UNPRIV_MASK;
+ entry->ebx &= 0;
+ break;
+ /* Intel PT */
+ case 0x14:
+ if (!kvm_cpu_cap_has(X86_FEATURE_INTEL_PT)) {
+ entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
+ break;
+ }
+
+ for (i = 1, max_idx = entry->eax; i <= max_idx; ++i) {
+ if (!do_host_cpuid(array, function, i))
+ goto out;
+ }
+ break;
+ /* Intel AMX TILE */
+ case 0x1d:
+ if (!kvm_cpu_cap_has(X86_FEATURE_AMX_TILE)) {
+ entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
+ break;
+ }
+
+ for (i = 1, max_idx = entry->eax; i <= max_idx; ++i) {
+ if (!do_host_cpuid(array, function, i))
+ goto out;
+ }
+ break;
+ case 0x1e: /* TMUL information */
+ if (!kvm_cpu_cap_has(X86_FEATURE_AMX_TILE)) {
+ entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
+ break;
+ }
+
+ max_idx = entry->eax = min(entry->eax, 1u);
+
+ /* KVM only supports up to 0x1e.0x1, capped above via min(). */
+ if (max_idx >= 1) {
+ entry = do_host_cpuid(array, function, 1);
+ if (!entry)
+ goto out;
+
+ cpuid_entry_override(entry, CPUID_1E_1_EAX);
+ entry->ebx = 0;
+ entry->ecx = 0;
+ entry->edx = 0;
+ }
+ break;
+ case 0x24: {
+ u8 avx10_version;
+
+ if (!kvm_cpu_cap_has(X86_FEATURE_AVX10)) {
+ entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
+ break;
+ }
+
+ max_idx = entry->eax = min(entry->eax, 1u);
+ /*
+ * The AVX10 version is encoded in EBX[7:0]. Note, the version
+ * is guaranteed to be >=1 if AVX10 is supported. Note #2, the
+ * version needs to be captured before overriding EBX features!
+ */
+ avx10_version = min_t(u8, entry->ebx & 0xff, 2);
+ cpuid_entry_override(entry, CPUID_24_0_EBX);
+ entry->ebx |= avx10_version;
+
+ entry->ecx = 0;
+ entry->edx = 0;
+
+ /* KVM only supports up to 0x24.0x1, capped above via min(). */
+ if (max_idx >= 1) {
+ entry = do_host_cpuid(array, function, 1);
+ if (!entry)
+ goto out;
+
+ cpuid_entry_override(entry, CPUID_24_1_ECX);
+ entry->eax = 0;
+ entry->ebx = 0;
+ entry->edx = 0;
+ }
+ break;
+ }
+ case KVM_CPUID_SIGNATURE: {
+ const u32 *sigptr = (const u32 *)KVM_SIGNATURE;
+ entry->eax = KVM_CPUID_FEATURES;
+ entry->ebx = sigptr[0];
+ entry->ecx = sigptr[1];
+ entry->edx = sigptr[2];
+ break;
+ }
+ case KVM_CPUID_FEATURES:
+ entry->eax = (1 << KVM_FEATURE_CLOCKSOURCE) |
+ (1 << KVM_FEATURE_NOP_IO_DELAY) |
+ (1 << KVM_FEATURE_CLOCKSOURCE2) |
+ (1 << KVM_FEATURE_ASYNC_PF) |
+ (1 << KVM_FEATURE_PV_EOI) |
+ (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT) |
+ (1 << KVM_FEATURE_PV_UNHALT) |
+ (1 << KVM_FEATURE_PV_TLB_FLUSH) |
+ (1 << KVM_FEATURE_ASYNC_PF_VMEXIT) |
+ (1 << KVM_FEATURE_PV_SEND_IPI) |
+ (1 << KVM_FEATURE_POLL_CONTROL) |
+ (1 << KVM_FEATURE_PV_SCHED_YIELD) |
+ (1 << KVM_FEATURE_ASYNC_PF_INT);
+
+ if (sched_info_on())
+ entry->eax |= (1 << KVM_FEATURE_STEAL_TIME);
+
+ entry->ebx = 0;
+ entry->ecx = 0;
+ entry->edx = 0;
+ break;
+ case 0x80000000:
+ entry->eax = min(entry->eax, 0x80000022);
+ /*
+ * Serializing LFENCE is reported in a multitude of ways, and
+ * NullSegClearsBase is not reported in CPUID on Zen2; help
+ * userspace by providing the CPUID leaf ourselves.
+ *
+ * However, only do it if the host has CPUID leaf 0x8000001d.
+ * QEMU thinks that it can query the host blindly for that
+ * CPUID leaf if KVM reports that it supports 0x8000001d or
+ * above. The processor merrily returns values from the
+ * highest Intel leaf which QEMU tries to use as the guest's
+ * 0x8000001d. Even worse, this can result in an infinite
+ * loop if said highest leaf has no subleaves indexed by ECX.
+ */
+ if (entry->eax >= 0x8000001d &&
+ (cpu_feature_enabled(X86_FEATURE_LFENCE_RDTSC)
+ || !static_cpu_has_bug(X86_BUG_NULL_SEG)))
+ entry->eax = max(entry->eax, 0x80000021);
+ break;
+ case 0x80000001:
+ entry->ebx &= ~GENMASK(27, 16);
+ cpuid_entry_override(entry, CPUID_8000_0001_EDX);
+ cpuid_entry_override(entry, CPUID_8000_0001_ECX);
+ break;
+ case 0x80000005:
+ /* Pass host L1 cache and TLB info. */
+ break;
+ case 0x80000006:
+ /* Drop reserved bits, pass host L2 cache and TLB info. */
+ entry->edx &= ~GENMASK(17, 16);
+ break;
+ case 0x80000007: /* Advanced power management */
+ cpuid_entry_override(entry, CPUID_8000_0007_EDX);
+
+ /* mask against host */
+ entry->edx &= boot_cpu_data.x86_power;
+ entry->eax = entry->ebx = entry->ecx = 0;
+ break;
+ case 0x80000008: {
+ /*
+ * GuestPhysAddrSize (EAX[23:16]) is intended for software
+ * use.
+ *
+ * KVM's ABI is to report the effective MAXPHYADDR for the
+ * guest in PhysAddrSize (phys_as), and the maximum
+ * *addressable* GPA in GuestPhysAddrSize (g_phys_as).
+ *
+ * GuestPhysAddrSize is valid if and only if TDP is enabled,
+ * in which case the max GPA that can be addressed by KVM may
+ * be less than the max GPA that can be legally generated by
+ * the guest, e.g. if MAXPHYADDR>48 but the CPU doesn't
+ * support 5-level TDP.
+ */
+ unsigned int virt_as = max((entry->eax >> 8) & 0xff, 48U);
+ unsigned int phys_as, g_phys_as;
+
+ /*
+ * If TDP (NPT) is disabled use the adjusted host MAXPHYADDR as
+ * the guest operates in the same PA space as the host, i.e.
+ * reductions in MAXPHYADDR for memory encryption affect shadow
+ * paging, too.
+ *
+ * If TDP is enabled, use the raw bare metal MAXPHYADDR as
+ * reductions to the HPAs do not affect GPAs. The max
+ * addressable GPA is the same as the max effective GPA, except
+ * that it's capped at 48 bits if 5-level TDP isn't supported
+ * (hardware processes bits 51:48 only when walking the fifth
+ * level page table).
+ */
+ if (!tdp_enabled) {
+ phys_as = boot_cpu_data.x86_phys_bits;
+ g_phys_as = 0;
+ } else {
+ phys_as = entry->eax & 0xff;
+ g_phys_as = phys_as;
+ if (kvm_mmu_get_max_tdp_level() < 5)
+ g_phys_as = min(g_phys_as, 48U);
+ }
+
+ entry->eax = phys_as | (virt_as << 8) | (g_phys_as << 16);
+ entry->ecx &= ~(GENMASK(31, 16) | GENMASK(11, 8));
+ entry->edx = 0;
+ cpuid_entry_override(entry, CPUID_8000_0008_EBX);
+ break;
+ }
+ case 0x8000000A:
+ if (!kvm_cpu_cap_has(X86_FEATURE_SVM)) {
+ entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
+ break;
+ }
+ entry->eax = 1; /* SVM revision 1 */
+ entry->ebx = 8; /* Lets support 8 ASIDs in case we add proper
+ ASID emulation to nested SVM */
+ entry->ecx = 0; /* Reserved */
+ cpuid_entry_override(entry, CPUID_8000_000A_EDX);
+ break;
+ case 0x80000019:
+ entry->ecx = entry->edx = 0;
+ break;
+ case 0x8000001a:
+ entry->eax &= GENMASK(2, 0);
+ entry->ebx = entry->ecx = entry->edx = 0;
+ break;
+ case 0x8000001e:
+ /* Do not return host topology information. */
+ entry->eax = entry->ebx = entry->ecx = 0;
+ entry->edx = 0; /* reserved */
+ break;
+ case 0x8000001F:
+ if (!kvm_cpu_cap_has(X86_FEATURE_SEV)) {
+ entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
+ } else {
+ cpuid_entry_override(entry, CPUID_8000_001F_EAX);
+ /* Clear NumVMPL since KVM does not support VMPL. */
+ entry->ebx &= ~GENMASK(31, 12);
+ /*
+ * Enumerate '0' for "PA bits reduction", the adjusted
+ * MAXPHYADDR is enumerated directly (see 0x80000008).
+ */
+ entry->ebx &= ~GENMASK(11, 6);
+ }
+ break;
+ case 0x80000020:
+ entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
+ break;
+ case 0x80000021:
+ entry->edx = 0;
+ cpuid_entry_override(entry, CPUID_8000_0021_EAX);
+
+ if (kvm_cpu_cap_has(X86_FEATURE_ERAPS))
+ entry->ebx &= GENMASK(23, 16);
+ else
+ entry->ebx = 0;
+
+ cpuid_entry_override(entry, CPUID_8000_0021_ECX);
+ break;
+ /* AMD Extended Performance Monitoring and Debug */
+ case 0x80000022: {
+ union cpuid_0x80000022_ebx ebx = { };
+
+ entry->ecx = entry->edx = 0;
+ if (!enable_pmu || !kvm_cpu_cap_has(X86_FEATURE_PERFMON_V2)) {
+ entry->eax = entry->ebx = 0;
+ break;
+ }
+
+ cpuid_entry_override(entry, CPUID_8000_0022_EAX);
+
+ ebx.split.num_core_pmc = kvm_pmu_cap.num_counters_gp;
+ entry->ebx = ebx.full;
+ break;
+ }
+ /*Add support for Centaur's CPUID instruction*/
+ case 0xC0000000:
+ /*Just support up to 0xC0000004 now*/
+ entry->eax = min(entry->eax, 0xC0000004);
+ break;
+ case 0xC0000001:
+ cpuid_entry_override(entry, CPUID_C000_0001_EDX);
+ break;
+ case 3: /* Processor serial number */
+ case 5: /* MONITOR/MWAIT */
+ case 0xC0000002:
+ case 0xC0000003:
+ case 0xC0000004:
+ default:
+ entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
+ break;
+ }
+
+ r = 0;
+
+out:
+ put_cpu();
+
+ return r;
+}
+
+static int do_cpuid_func(struct kvm_cpuid_array *array, u32 func,
+ unsigned int type)
+{
+ if (type == KVM_GET_EMULATED_CPUID)
+ return __do_cpuid_func_emulated(array, func);
+
+ return __do_cpuid_func(array, func);
+}
+
+#define CENTAUR_CPUID_SIGNATURE 0xC0000000
+
+static int get_cpuid_func(struct kvm_cpuid_array *array, u32 func,
+ unsigned int type)
+{
+ u32 limit;
+ int r;
+
+ if (func == CENTAUR_CPUID_SIGNATURE &&
+ boot_cpu_data.x86_vendor != X86_VENDOR_CENTAUR &&
+ boot_cpu_data.x86_vendor != X86_VENDOR_ZHAOXIN)
+ return 0;
+
+ r = do_cpuid_func(array, func, type);
+ if (r)
+ return r;
+
+ limit = array->entries[array->nent - 1].eax;
+ for (func = func + 1; func <= limit; ++func) {
+ r = do_cpuid_func(array, func, type);
+ if (r)
+ break;
+ }
+
+ return r;
+}
+
+static bool sanity_check_entries(struct kvm_cpuid_entry2 __user *entries,
+ __u32 num_entries, unsigned int ioctl_type)
+{
+ int i;
+ __u32 pad[3];
+
+ if (ioctl_type != KVM_GET_EMULATED_CPUID)
+ return false;
+
+ /*
+ * We want to make sure that ->padding is being passed clean from
+ * userspace in case we want to use it for something in the future.
+ *
+ * Sadly, this wasn't enforced for KVM_GET_SUPPORTED_CPUID and so we
+ * have to give ourselves satisfied only with the emulated side. /me
+ * sheds a tear.
+ */
+ for (i = 0; i < num_entries; i++) {
+ if (copy_from_user(pad, entries[i].padding, sizeof(pad)))
+ return true;
+
+ if (pad[0] || pad[1] || pad[2])
+ return true;
+ }
+ return false;
+}
+
+int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
+ struct kvm_cpuid_entry2 __user *entries,
+ unsigned int type)
+{
+ static const u32 funcs[] = {
+ 0, 0x80000000, CENTAUR_CPUID_SIGNATURE, KVM_CPUID_SIGNATURE,
+ };
+
+ struct kvm_cpuid_array array = {
+ .nent = 0,
+ };
+ int r, i;
+
+ if (cpuid->nent < 1)
+ return -E2BIG;
+ if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
+ cpuid->nent = KVM_MAX_CPUID_ENTRIES;
+
+ if (sanity_check_entries(entries, cpuid->nent, type))
+ return -EINVAL;
+
+ array.entries = kvzalloc_objs(struct kvm_cpuid_entry2, cpuid->nent);
+ if (!array.entries)
+ return -ENOMEM;
+
+ array.maxnent = cpuid->nent;
+
+ for (i = 0; i < ARRAY_SIZE(funcs); i++) {
+ r = get_cpuid_func(&array, funcs[i], type);
+ if (r)
+ goto out_free;
+ }
+ cpuid->nent = array.nent;
+
+ if (copy_to_user(entries, array.entries,
+ array.nent * sizeof(struct kvm_cpuid_entry2)))
+ r = -EFAULT;
+
+out_free:
+ kvfree(array.entries);
+ return r;
+}
+
+/*
+ * Intel CPUID semantics treats any query for an out-of-range leaf as if the
+ * highest basic leaf (i.e. CPUID.0H:EAX) were requested. AMD CPUID semantics
+ * returns all zeroes for any undefined leaf, whether or not the leaf is in
+ * range. Centaur/VIA follows Intel semantics.
+ *
+ * A leaf is considered out-of-range if its function is higher than the maximum
+ * supported leaf of its associated class or if its associated class does not
+ * exist.
+ *
+ * There are three primary classes to be considered, with their respective
+ * ranges described as "<base> - <top>[,<base2> - <top2>] inclusive. A primary
+ * class exists if a guest CPUID entry for its <base> leaf exists. For a given
+ * class, CPUID.<base>.EAX contains the max supported leaf for the class.
+ *
+ * - Basic: 0x00000000 - 0x3fffffff, 0x50000000 - 0x7fffffff
+ * - Hypervisor: 0x40000000 - 0x4fffffff
+ * - Extended: 0x80000000 - 0xbfffffff
+ * - Centaur: 0xc0000000 - 0xcfffffff
+ *
+ * The Hypervisor class is further subdivided into sub-classes that each act as
+ * their own independent class associated with a 0x100 byte range. E.g. if Qemu
+ * is advertising support for both HyperV and KVM, the resulting Hypervisor
+ * CPUID sub-classes are:
+ *
+ * - HyperV: 0x40000000 - 0x400000ff
+ * - KVM: 0x40000100 - 0x400001ff
+ */
+static struct kvm_cpuid_entry2 *
+get_out_of_range_cpuid_entry(struct kvm_vcpu *vcpu, u32 *fn_ptr, u32 index)
+{
+ struct kvm_cpuid_entry2 *basic, *class;
+ u32 function = *fn_ptr;
+
+ basic = kvm_find_cpuid_entry(vcpu, 0);
+ if (!basic)
+ return NULL;
+
+ if (is_guest_vendor_amd(basic->ebx, basic->ecx, basic->edx) ||
+ is_guest_vendor_hygon(basic->ebx, basic->ecx, basic->edx))
+ return NULL;
+
+ if (function >= 0x40000000 && function <= 0x4fffffff)
+ class = kvm_find_cpuid_entry(vcpu, function & 0xffffff00);
+ else if (function >= 0xc0000000)
+ class = kvm_find_cpuid_entry(vcpu, 0xc0000000);
+ else
+ class = kvm_find_cpuid_entry(vcpu, function & 0x80000000);
+
+ if (class && function <= class->eax)
+ return NULL;
+
+ /*
+ * Leaf specific adjustments are also applied when redirecting to the
+ * max basic entry, e.g. if the max basic leaf is 0xb but there is no
+ * entry for CPUID.0xb.index (see below), then the output value for EDX
+ * needs to be pulled from CPUID.0xb.1.
+ */
+ *fn_ptr = basic->eax;
+
+ /*
+ * The class does not exist or the requested function is out of range;
+ * the effective CPUID entry is the max basic leaf. Note, the index of
+ * the original requested leaf is observed!
+ */
+ return kvm_find_cpuid_entry_index(vcpu, basic->eax, index);
+}
+
+bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx,
+ u32 *ecx, u32 *edx, bool exact_only)
+{
+ u32 orig_function = *eax, function = *eax, index = *ecx;
+ struct kvm_cpuid_entry2 *entry;
+ bool exact, used_max_basic = false;
+
+ if (vcpu->arch.cpuid_dynamic_bits_dirty)
+ kvm_update_cpuid_runtime(vcpu);
+
+ entry = kvm_find_cpuid_entry_index(vcpu, function, index);
+ exact = !!entry;
+
+ if (!entry && !exact_only) {
+ entry = get_out_of_range_cpuid_entry(vcpu, &function, index);
+ used_max_basic = !!entry;
+ }
+
+ if (entry) {
+ *eax = entry->eax;
+ *ebx = entry->ebx;
+ *ecx = entry->ecx;
+ *edx = entry->edx;
+ if (function == 7 && index == 0) {
+ u64 data;
+ if ((*ebx & (feature_bit(RTM) | feature_bit(HLE))) &&
+ !kvm_msr_read(vcpu, MSR_IA32_TSX_CTRL, &data) &&
+ (data & TSX_CTRL_CPUID_CLEAR))
+ *ebx &= ~(feature_bit(RTM) | feature_bit(HLE));
+ } else if (function == 0x80000007) {
+ if (kvm_hv_invtsc_suppressed(vcpu))
+ *edx &= ~feature_bit(CONSTANT_TSC);
+ } else if (IS_ENABLED(CONFIG_KVM_XEN) &&
+ kvm_xen_is_tsc_leaf(vcpu, function)) {
+ /*
+ * Update guest TSC frequency information if necessary.
+ * Ignore failures, there is no sane value that can be
+ * provided if KVM can't get the TSC frequency.
+ */
+ if (kvm_check_request(KVM_REQ_CLOCK_UPDATE, vcpu))
+ kvm_guest_time_update(vcpu);
+
+ if (index == 1) {
+ *ecx = vcpu->arch.pvclock_tsc_mul;
+ *edx = vcpu->arch.pvclock_tsc_shift;
+ } else if (index == 2) {
+ *eax = vcpu->arch.hw_tsc_khz;
+ }
+ }
+ } else {
+ *eax = *ebx = *ecx = *edx = 0;
+ /*
+ * When leaf 0BH or 1FH is defined, CL is pass-through
+ * and EDX is always the x2APIC ID, even for undefined
+ * subleaves. Index 1 will exist iff the leaf is
+ * implemented, so we pass through CL iff leaf 1
+ * exists. EDX can be copied from any existing index.
+ */
+ if (function == 0xb || function == 0x1f) {
+ entry = kvm_find_cpuid_entry_index(vcpu, function, 1);
+ if (entry) {
+ *ecx = index & 0xff;
+ *edx = entry->edx;
+ }
+ }
+ }
+ trace_kvm_cpuid(orig_function, index, *eax, *ebx, *ecx, *edx, exact,
+ used_max_basic);
+ return exact;
+}
+EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_cpuid);
+
+int kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
+{
+ u32 eax, ebx, ecx, edx;
+
+ if (!kvm_is_cpuid_allowed(vcpu)) {
+ kvm_queue_exception_e(vcpu, GP_VECTOR, 0);
+ return 1;
+ }
+
+ eax = kvm_eax_read(vcpu);
+ ecx = kvm_ecx_read(vcpu);
+ kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx, false);
+ kvm_eax_write(vcpu, eax);
+ kvm_ebx_write(vcpu, ebx);
+ kvm_ecx_write(vcpu, ecx);
+ kvm_edx_write(vcpu, edx);
+ return kvm_skip_emulated_instruction(vcpu);
+}
+EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_emulate_cpuid);