Messages in this thread | | | Date | Fri, 30 Jun 2023 16:01:38 +0800 | From | Chao Gao <> | Subject | Re: [PATCH 01/12] KVM: x86: Add a framework for enabling KVM-governed x86 features |
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On Fri, Feb 17, 2023 at 03:10:11PM -0800, Sean Christopherson wrote: >+static __always_inline void kvm_governed_feature_set(struct kvm_vcpu *vcpu, >+ unsigned int x86_feature) >+{ >+ BUILD_BUG_ON(KVM_NR_GOVERNED_FEATURES > >+ sizeof(vcpu->arch.governed_features.enabled) * BITS_PER_BYTE); >+ >+ vcpu->arch.governed_features.enabled |= kvm_governed_feature_bit(x86_feature); >+} >+ >+static __always_inline void kvm_governed_feature_check_and_set(struct kvm_vcpu *vcpu, >+ unsigned int x86_feature) >+{ >+ if (guest_cpuid_has(vcpu, x86_feature))
Most callers in this series are conditional on either boot_cpu_has() or some local variables. Can we convert them to kvm_cpu_cap_has() and incorporate them within this function? i.e.,
if (kvm_cpu_cap_has(x86_feature) && guest_cpuid_has(vcpu, x86_feature))
The benefits of doing so are 1. callers needn't repeat
if (kvm_cpu_cap_has(x86_feature)) kvm_governed_feature_check_and_set(x86_feature)
2. this fits the idea better that guests can use a governed feature only if host supports it _and_ QEMU exposes it to the guest.
>+ kvm_governed_feature_set(vcpu, x86_feature); >+} >+
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