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| author | Sean Christopherson <seanjc@google.com> | 2024-11-28 04:33:52 +0300 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2024-12-19 01:19:48 +0300 |
| commit | 264969b48a295e3fd89f01d3584a9f3cf6b47eb1 (patch) | |
| tree | 2553e92348c5741e2a909d1cf70dca992b0564f1 | |
| parent | 6eac4d99a9677a35947aa115bbc60266def40c3e (diff) | |
| download | linux-264969b48a295e3fd89f01d3584a9f3cf6b47eb1.tar.xz | |
KVM: x86: Add a macro to precisely handle aliased 0x1.EDX CPUID features
Add a macro to precisely handle CPUID features that AMD duplicated from
CPUID.0x1.EDX into CPUID.0x8000_0001.EDX. This will allow adding an
assert that all features passed to kvm_cpu_cap_init() match the word being
processed, e.g. to prevent passing a feature from CPUID 0x7 to CPUID 0x1.
Because the kernel simply reuses the X86_FEATURE_* definitions from
CPUID.0x1.EDX, KVM's use of the aliased features would result in false
positives from such an assert.
No functional change intended.
Link: https://lore.kernel.org/r/20241128013424.4096668-26-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 47 |
1 files changed, 29 insertions, 18 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index bd1d54e25414..11cd176a26f8 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -669,6 +669,16 @@ static __always_inline void kvm_cpu_cap_init(enum cpuid_leafs leaf, u32 mask) (IS_ENABLED(CONFIG_X86_64) ? F(name) : 0); \ }) +/* + * 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); \ + feature_bit(name); \ +}) + void kvm_set_cpu_caps(void) { memset(kvm_cpu_caps, 0, sizeof(kvm_cpu_caps)); @@ -913,30 +923,30 @@ void kvm_set_cpu_caps(void) ); kvm_cpu_cap_init(CPUID_8000_0001_EDX, - F(FPU) | - F(VME) | - F(DE) | - F(PSE) | - F(TSC) | - F(MSR) | - F(PAE) | - F(MCE) | - F(CX8) | - F(APIC) | + 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) | 0 /* Reserved */ | F(SYSCALL) | - F(MTRR) | - F(PGE) | - F(MCA) | - F(CMOV) | - F(PAT) | - F(PSE36) | + 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) | 0 /* Reserved */ | F(NX) | 0 /* Reserved */ | F(MMXEXT) | - F(MMX) | - F(FXSR) | + ALIASED_1_EDX_F(MMX) | + ALIASED_1_EDX_F(FXSR) | F(FXSR_OPT) | X86_64_F(GBPAGES) | F(RDTSCP) | @@ -1076,6 +1086,7 @@ EXPORT_SYMBOL_GPL(kvm_set_cpu_caps); #undef F #undef SF #undef X86_64_F +#undef ALIASED_1_EDX_F struct kvm_cpuid_array { struct kvm_cpuid_entry2 *entries; |