Commit 43bd9ef4 authored Aug 09, 2020 by Paolo Bonzini

x86: Expose SERIALIZE for supported cpuid

The SERIALIZE instruction is supported by Tntel processors, like
Sapphire Rapids. SERIALIZE is a faster serializing instruction which
does not modify registers, arithmetic flags or memory, will not cause VM
exit. It's availability is indicated by CPUID.(EAX=7,ECX=0):ECX[bit 14].

Expose it in KVM supported CPUID. This way, KVM could pass this
information to guests and they can make use of these features accordingly.

Signed-off-by: Cathy Zhang <cathy.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

parent 0378daef

arch/x86/kvm/cpuid.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -370,7 +370,8 @@ 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. */

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