Sean Christopherson <seanjc@xxxxxxxxxx> writes: > On Fri, Sep 16, 2022, Vitaly Kuznetsov wrote: >> CPUID_8000_0007_EDX may come handy when X86_FEATURE_CONSTANT_TSC >> needs to be checked. >> >> No functional change intended. >> >> Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> >> --- >> arch/x86/kvm/cpuid.c | 4 ++++ >> arch/x86/kvm/reverse_cpuid.h | 9 ++++++++- >> 2 files changed, 12 insertions(+), 1 deletion(-) >> >> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c >> index 75dcf7a72605..f68b14053c9b 100644 >> --- a/arch/x86/kvm/cpuid.c >> +++ b/arch/x86/kvm/cpuid.c >> @@ -669,6 +669,10 @@ void kvm_set_cpu_caps(void) >> if (!tdp_enabled && IS_ENABLED(CONFIG_X86_64)) >> kvm_cpu_cap_set(X86_FEATURE_GBPAGES); >> >> + kvm_cpu_cap_init_scattered(CPUID_8000_0007_EDX, >> + SF(CONSTANT_TSC) >> + ); > > The scattered leaf needs to be used in __do_cpuid_func(), e.g. > > diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c > index ffdc28684cb7..c91f23bb3605 100644 > --- a/arch/x86/kvm/cpuid.c > +++ b/arch/x86/kvm/cpuid.c > @@ -1137,8 +1137,8 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) > /* L2 cache and TLB: pass through host info. */ > break; > case 0x80000007: /* Advanced power management */ > - /* invariant TSC is CPUID.80000007H:EDX[8] */ > - entry->edx &= (1 << 8); > + cpuid_entry_override(entry, CPUID_8000_0007_EDX); > + Ah, missed that part! Will add. > /* mask against host */ > entry->edx &= boot_cpu_data.x86_power; > entry->eax = entry->ebx = entry->ecx = 0; > -- Vitaly
