Commit dea6e140 authored by Vitaly Kuznetsov's avatar Vitaly Kuznetsov Committed by Paolo Bonzini
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KVM: x86: hyper-v: Cache HYPERV_CPUID_NESTED_FEATURES CPUID leaf 



KVM has to check guest visible HYPERV_CPUID_NESTED_FEATURES.EBX CPUID
leaf to know which Enlightened VMCS definition to use (original or 2022
update). Cache the leaf along with other Hyper-V CPUID feature leaves
to make the check quick.

Reviewed-by: default avatarMaxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220830133737.1539624-12-vkuznets@redhat.com


Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent c9d31986

arch/x86/include/asm/kvm_host.h

+2 −0
Original line number Diff line number Diff line
@@ -615,6 +615,8 @@ struct kvm_vcpu_hv { 
		u32 enlightenments_eax; /* HYPERV_CPUID_ENLIGHTMENT_INFO.EAX */

		u32 enlightenments_ebx; /* HYPERV_CPUID_ENLIGHTMENT_INFO.EBX */

		u32 syndbg_cap_eax; /* HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES.EAX */

		u32 nested_eax; /* HYPERV_CPUID_NESTED_FEATURES.EAX */

		u32 nested_ebx; /* HYPERV_CPUID_NESTED_FEATURES.EBX */

	} cpuid_cache;

};

arch/x86/kvm/hyperv.c

+6 −0
Original line number Diff line number Diff line
@@ -2018,6 +2018,12 @@ void kvm_hv_set_cpuid(struct kvm_vcpu *vcpu, bool hyperv_enabled) 
	entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES);

	if (entry)

		hv_vcpu->cpuid_cache.syndbg_cap_eax = entry->eax;



	entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_NESTED_FEATURES);

	if (entry) {

		hv_vcpu->cpuid_cache.nested_eax = entry->eax;

		hv_vcpu->cpuid_cache.nested_ebx = entry->ebx;

	}

}



int kvm_hv_set_enforce_cpuid(struct kvm_vcpu *vcpu, bool enforce)