On July 14, 2020 5:03:31 PM PDT, "Zhang, Cathy" <cathy.zhang@xxxxxxxxx> wrote: >On 7/15/2020 7:05 AM, hpa@xxxxxxxxx wrote: >> On July 14, 2020 3:42:08 PM PDT, "Zhang, Cathy" ><cathy.zhang@xxxxxxxxx> wrote: >>> On 7/14/2020 11:00 AM, Sean Christopherson wrote: >>>> On Tue, Jul 07, 2020 at 10:16:22AM +0800, Cathy Zhang wrote: >>>>> SERIALIZE instruction is supported by intel processors, >>>>> like Sapphire Rapids. Expose it in KVM supported cpuid. >>>> Providing at least a rough overview of the instruction, e.g. its >>> enumeration, >>>> usage, fault rules, controls, etc... would be nice. In isolation, >>> the >>>> changelog isn't remotely helpful in understanding the correctness >of >>> the >>>> patch. >>> Thanks Sean! Add it in the next version. >>>>> Signed-off-by: Cathy Zhang <cathy.zhang@xxxxxxxxx> >>>>> --- >>>>> arch/x86/kvm/cpuid.c | 3 ++- >>>>> 1 file changed, 2 insertions(+), 1 deletion(-) >>>>> >>>>> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c >>>>> index 8a294f9..e603aeb 100644 >>>>> --- a/arch/x86/kvm/cpuid.c >>>>> +++ b/arch/x86/kvm/cpuid.c >>>>> @@ -341,7 +341,8 @@ void kvm_set_cpu_caps(void) >>>>> kvm_cpu_cap_mask(CPUID_7_EDX, >>>>> F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) | >>>>> F(SPEC_CTRL_SSBD) | F(ARCH_CAPABILITIES) | F(INTEL_STIBP) | >>>>> - F(MD_CLEAR) | F(AVX512_VP2INTERSECT) | F(FSRM) >>>>> + F(MD_CLEAR) | F(AVX512_VP2INTERSECT) | F(FSRM) | >>>>> + F(SERIALIZE) >>>>> ); >>>>> >>>>> /* TSC_ADJUST and ARCH_CAPABILITIES are emulated in software. >*/ >>>>> -- >>>>> 1.8.3.1 >>>>> >> At least that one is easy: SERIALIZE is architecturally a NOP, but >with hard serialization, like CPUID or IRET. >SERIALIZE does not modify registers, arithmetic flags or memory, which >is different with CPUID. That's what I meant with it being an architectural NOP. -- Sent from my Android device with K-9 Mail. Please excuse my brevity.
