On Fri, Oct 07, 2022, Sean Christopherson wrote: > On Fri, Oct 07, 2022, Jim Mattson wrote: > > CPUID.80000021H:EAX[bit 9] indicates that the SMM_CTL MSR (0xc0010116) > > is not supported. This defeature can be advertised by > > KVM_GET_SUPPORTED_CPUID regardless of whether or not the host > > enumerates it. > > Might be worth noting that KVM will only enumerate the bit if the host happens to > have a max extend leaf > 80000021. > > > > Signed-off-by: Jim Mattson <jmattson@xxxxxxxxxx> > > --- > > arch/x86/kvm/cpuid.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c > > index 2796dde06302..b748fac2ae37 100644 > > --- a/arch/x86/kvm/cpuid.c > > +++ b/arch/x86/kvm/cpuid.c > > @@ -1199,8 +1199,12 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) > > * Other defined bits are for MSRs that KVM does not expose: > > * EAX 3 SPCL, SMM page configuration lock > > * EAX 13 PCMSR, Prefetch control MSR > > + * > > + * KVM doesn't support SMM_CTL. > > + * EAX 9 SMM_CTL MSR is not supported > > */ > > entry->eax &= BIT(0) | BIT(2) | BIT(6); > > I don't suppose I can bribe you to add a kvm_only_cpuid_leafs entry for these? :-) Ha! Someone else must have heard me whining :-) https://lore.kernel.org/all/20221129235816.188737-5-kim.phillips@xxxxxxx
