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. Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> --- arch/x86/kvm/cpuid.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 5e3b97d06374..f2bd2f5c4ea3 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -88,6 +88,16 @@ u32 xstate_required_size(u64 xstate_bv, bool compacted) 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 AF(name) \ +({ \ + BUILD_BUG_ON(__feature_leaf(X86_FEATURE_##name) != CPUID_1_EDX); \ + feature_bit(name); \ +}) + /* * Magic value used by KVM when querying userspace-provided CPUID entries and * doesn't care about the CPIUD index because the index of the function in @@ -758,13 +768,13 @@ 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) | 0 /* Reserved */ | F(SYSCALL) | - F(MTRR) | F(PGE) | F(MCA) | F(CMOV) | - F(PAT) | F(PSE36) | 0 /* Reserved */ | - F(NX) | 0 /* Reserved */ | F(MMXEXT) | F(MMX) | - F(FXSR) | F(FXSR_OPT) | X86_64_F(GBPAGES) | F(RDTSCP) | + AF(FPU) | AF(VME) | AF(DE) | AF(PSE) | + AF(TSC) | AF(MSR) | AF(PAE) | AF(MCE) | + AF(CX8) | AF(APIC) | 0 /* Reserved */ | F(SYSCALL) | + AF(MTRR) | AF(PGE) | AF(MCA) | AF(CMOV) | + AF(PAT) | AF(PSE36) | 0 /* Reserved */ | + F(NX) | 0 /* Reserved */ | F(MMXEXT) | AF(MMX) | + AF(FXSR) | F(FXSR_OPT) | X86_64_F(GBPAGES) | F(RDTSCP) | 0 /* Reserved */ | X86_64_F(LM) | F(3DNOWEXT) | F(3DNOW) ); -- 2.45.0.215.g3402c0e53f-goog