On Mon, Dec 7, 2020 at 2:38 PM Babu Moger <babu.moger@xxxxxxx> wrote: > > Newer AMD processors have a feature to virtualize the use of the SPEC_CTRL > MSR. This feature is identified via CPUID 0x8000000A_EDX[20]. When present, > the SPEC_CTRL MSR is automatically virtualized and no longer requires > hypervisor intervention. > > Signed-off-by: Babu Moger <babu.moger@xxxxxxx> > --- > arch/x86/include/asm/cpufeatures.h | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h > index dad350d42ecf..d649ac5ed7c7 100644 > --- a/arch/x86/include/asm/cpufeatures.h > +++ b/arch/x86/include/asm/cpufeatures.h > @@ -335,6 +335,7 @@ > #define X86_FEATURE_AVIC (15*32+13) /* Virtual Interrupt Controller */ > #define X86_FEATURE_V_VMSAVE_VMLOAD (15*32+15) /* Virtual VMSAVE VMLOAD */ > #define X86_FEATURE_VGIF (15*32+16) /* Virtual GIF */ > +#define X86_FEATURE_V_SPEC_CTRL (15*32+20) /* Virtual SPEC_CTRL */ Shouldn't this bit be reported by KVM_GET_SUPPORTED_CPUID when it's enumerated on the host? > /* Intel-defined CPU features, CPUID level 0x00000007:0 (ECX), word 16 */ > #define X86_FEATURE_AVX512VBMI (16*32+ 1) /* AVX512 Vector Bit Manipulation instructions*/ >
