Add one last (hopefully) CPUID feature macro, RUNTIME_F(), and use it to track features that KVM supports, but that are only set at runtime (in response to other state), and aren't advertised to userspace via KVM_GET_SUPPORTED_CPUID.
Currently, RUNTIME_F() is mostly just documentation, but tracking all KVM-supported features will allow for asserting, at build time, take), that all features that are set, cleared, *or* checked by KVM are known to kvm_set_cpu_caps(). No functional change intended. Signed-off-by: Sean Christopherson <[email protected]> --- arch/x86/kvm/cpuid.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 5ac5fe2febf7..e03154b9833f 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -768,6 +768,16 @@ do { \ 0; \ }) +/* + * 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); \ + 0; \ +}) + /* * Undefine the MSR bit macro to avoid token concatenation issues when * processing X86_FEATURE_SPEC_CTRL_SSBD. @@ -790,9 +800,11 @@ void kvm_set_cpu_caps(void) VENDOR_F(DTES64) | /* * NOTE: MONITOR (and MWAIT) are emulated as NOP, but *not* - * advertised to guests via CPUID! + * 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. */ - 0 /* MONITOR */ | + RUNTIME_F(MWAIT) | VENDOR_F(VMX) | 0 /* DS-CPL, SMX, EST */ | 0 /* TM2 */ | @@ -813,7 +825,7 @@ void kvm_set_cpu_caps(void) EMULATED_F(TSC_DEADLINE_TIMER) | F(AES) | F(XSAVE) | - 0 /* OSXSAVE */ | + RUNTIME_F(OSXSAVE) | F(AVX) | F(F16C) | F(RDRAND) | @@ -887,7 +899,7 @@ void kvm_set_cpu_caps(void) F(AVX512VBMI) | PASSTHROUGH_F(LA57) | F(PKU) | - 0 /*OSPKE*/ | + RUNTIME_F(OSPKE) | F(RDPID) | F(AVX512_VPOPCNTDQ) | F(UMIP) | @@ -1189,6 +1201,7 @@ EXPORT_SYMBOL_GPL(kvm_set_cpu_caps); #undef PASSTHROUGH_F #undef ALIASED_1_EDX_F #undef VENDOR_F +#undef RUNTIME_F struct kvm_cpuid_array { struct kvm_cpuid_entry2 *entries; -- 2.47.0.338.g60cca15819-goog
