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KVM: x86: Always operate on kvm_vcpu data in cpuid_entry2_find()
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Now that KVM sets vcpu->arch.cpuid_{entries,nent} before processing the
incoming CPUID entries during KVM_SET_CPUID{,2}, drop the @entries and
@nent params from cpuid_entry2_find() and unconditionally operate on the
vCPU state.

No functional change intended.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20241128013424.4096668-35-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
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Sean Christopherson committed Dec 18, 2024
1 parent a5b3271 commit 285185f
Showing 1 changed file with 21 additions and 41 deletions.
62 changes: 21 additions & 41 deletions arch/x86/kvm/cpuid.c
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Original file line number Diff line number Diff line change
Expand Up @@ -91,8 +91,8 @@ u32 xstate_required_size(u64 xstate_bv, bool compacted)
*/
#define KVM_CPUID_INDEX_NOT_SIGNIFICANT -1ull

static inline struct kvm_cpuid_entry2 *cpuid_entry2_find(
struct kvm_cpuid_entry2 *entries, int nent, u32 function, u64 index)
static struct kvm_cpuid_entry2 *cpuid_entry2_find(struct kvm_vcpu *vcpu,
u32 function, u64 index)
{
struct kvm_cpuid_entry2 *e;
int i;
Expand All @@ -109,8 +109,8 @@ static inline struct kvm_cpuid_entry2 *cpuid_entry2_find(
*/
lockdep_assert_irqs_enabled();

for (i = 0; i < nent; i++) {
e = &entries[i];
for (i = 0; i < vcpu->arch.cpuid_nent; i++) {
e = &vcpu->arch.cpuid_entries[i];

if (e->function != function)
continue;
Expand Down Expand Up @@ -144,16 +144,14 @@ static inline struct kvm_cpuid_entry2 *cpuid_entry2_find(

static int kvm_check_cpuid(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *entries = vcpu->arch.cpuid_entries;
int nent = vcpu->arch.cpuid_nent;
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 = cpuid_entry2_find(entries, nent, 0x80000008,
best = cpuid_entry2_find(vcpu, 0x80000008,
KVM_CPUID_INDEX_NOT_SIGNIFICANT);
if (best) {
int vaddr_bits = (best->eax & 0xff00) >> 8;
Expand All @@ -166,7 +164,7 @@ static int kvm_check_cpuid(struct kvm_vcpu *vcpu)
* Exposing dynamic xfeatures to the guest requires additional
* enabling in the FPU, e.g. to expand the guest XSAVE state size.
*/
best = cpuid_entry2_find(entries, nent, 0xd, 0);
best = cpuid_entry2_find(vcpu, 0xd, 0);
if (!best)
return 0;

Expand Down Expand Up @@ -212,15 +210,15 @@ static int kvm_cpuid_check_equal(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2
return 0;
}

static struct kvm_hypervisor_cpuid __kvm_get_hypervisor_cpuid(struct kvm_cpuid_entry2 *entries,
int nent, const char *sig)
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_hypervisor_cpuid_base(base) {
entry = cpuid_entry2_find(entries, nent, base, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
entry = cpuid_entry2_find(vcpu, base, KVM_CPUID_INDEX_NOT_SIGNIFICANT);

if (entry) {
u32 signature[3];
Expand All @@ -240,13 +238,6 @@ static struct kvm_hypervisor_cpuid __kvm_get_hypervisor_cpuid(struct kvm_cpuid_e
return cpuid;
}

static struct kvm_hypervisor_cpuid kvm_get_hypervisor_cpuid(struct kvm_vcpu *vcpu,
const char *sig)
{
return __kvm_get_hypervisor_cpuid(vcpu->arch.cpuid_entries,
vcpu->arch.cpuid_nent, sig);
}

static u32 kvm_apply_cpuid_pv_features_quirk(struct kvm_vcpu *vcpu)
{
struct kvm_hypervisor_cpuid kvm_cpuid;
Expand All @@ -270,23 +261,22 @@ static u32 kvm_apply_cpuid_pv_features_quirk(struct kvm_vcpu *vcpu)
* 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_cpuid_entry2 *entries, int nent)
static u64 cpuid_get_supported_xcr0(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;

best = cpuid_entry2_find(entries, nent, 0xd, 0);
best = cpuid_entry2_find(vcpu, 0xd, 0);
if (!best)
return 0;

return (best->eax | ((u64)best->edx << 32)) & kvm_caps.supported_xcr0;
}

static void __kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *entries,
int nent)
void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;

best = cpuid_entry2_find(entries, nent, 1, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
best = cpuid_entry2_find(vcpu, 1, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
if (best) {
/* Update OSXSAVE bit */
if (boot_cpu_has(X86_FEATURE_XSAVE))
Expand All @@ -297,43 +287,36 @@ static void __kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu, struct kvm_cpuid_e
vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE);
}

best = cpuid_entry2_find(entries, nent, 7, 0);
best = cpuid_entry2_find(vcpu, 7, 0);
if (best && boot_cpu_has(X86_FEATURE_PKU) && best->function == 0x7)
cpuid_entry_change(best, X86_FEATURE_OSPKE,
kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE));

best = cpuid_entry2_find(entries, nent, 0xD, 0);
best = cpuid_entry2_find(vcpu, 0xD, 0);
if (best)
best->ebx = xstate_required_size(vcpu->arch.xcr0, false);

best = cpuid_entry2_find(entries, nent, 0xD, 1);
best = cpuid_entry2_find(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, true);

if (!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT)) {
best = cpuid_entry2_find(entries, nent, 0x1, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
best = cpuid_entry2_find(vcpu, 0x1, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
if (best)
cpuid_entry_change(best, X86_FEATURE_MWAIT,
vcpu->arch.ia32_misc_enable_msr &
MSR_IA32_MISC_ENABLE_MWAIT);
}
}

void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu)
{
__kvm_update_cpuid_runtime(vcpu, vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent);
}
EXPORT_SYMBOL_GPL(kvm_update_cpuid_runtime);

static bool kvm_cpuid_has_hyperv(struct kvm_vcpu *vcpu)
{
#ifdef CONFIG_KVM_HYPERV
struct kvm_cpuid_entry2 *entries = vcpu->arch.cpuid_entries;
int nent = vcpu->arch.cpuid_nent;
struct kvm_cpuid_entry2 *entry;

entry = cpuid_entry2_find(entries, nent, HYPERV_CPUID_INTERFACE,
entry = cpuid_entry2_find(vcpu, HYPERV_CPUID_INTERFACE,
KVM_CPUID_INDEX_NOT_SIGNIFICANT);
return entry && entry->eax == HYPERV_CPUID_SIGNATURE_EAX;
#else
Expand Down Expand Up @@ -391,8 +374,7 @@ void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
kvm_apic_set_version(vcpu);
}

vcpu->arch.guest_supported_xcr0 =
cpuid_get_supported_xcr0(vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent);
vcpu->arch.guest_supported_xcr0 = cpuid_get_supported_xcr0(vcpu);

vcpu->arch.pv_cpuid.features = kvm_apply_cpuid_pv_features_quirk(vcpu);

Expand Down Expand Up @@ -1777,16 +1759,14 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
struct kvm_cpuid_entry2 *kvm_find_cpuid_entry_index(struct kvm_vcpu *vcpu,
u32 function, u32 index)
{
return cpuid_entry2_find(vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent,
function, index);
return cpuid_entry2_find(vcpu, function, index);
}
EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry_index);

struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
u32 function)
{
return cpuid_entry2_find(vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent,
function, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
return cpuid_entry2_find(vcpu, function, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
}
EXPORT_SYMBOL_GPL(kvm_find_cpuid_entry);

Expand Down

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