Re: [RFC PATCH 2/3] KVM: x86: Generate set of VMX feature MSRs using first/last definitions

From: Sean Christopherson
Date: Wed Aug 10 2022 - 10:41:08 EST


On Wed, Aug 10, 2022, Paolo Bonzini wrote:
> On 8/5/22 19:29, Sean Christopherson wrote:
> > +static void kvm_proble_feature_msr(u32 msr_index)
> > +{
> > + struct kvm_msr_entry msr = {
> > + .index = msr_index,
> > + };
> > +
> > + if (kvm_get_msr_feature(&msr))
> > + return;
> > +
> > + msr_based_features[num_msr_based_features++] = msr_index;
> > +}
> > +
> > static void kvm_init_msr_list(void)
> > {
> > u32 dummy[2];
> > @@ -6954,15 +6949,11 @@ static void kvm_init_msr_list(void)
> > emulated_msrs[num_emulated_msrs++] = emulated_msrs_all[i];
> > }
> > - for (i = 0; i < ARRAY_SIZE(msr_based_features_all); i++) {
> > - struct kvm_msr_entry msr;
> > + for (i = KVM_FIRST_EMULATED_VMX_MSR; i <= KVM_LAST_EMULATED_VMX_MSR; i++)
> > + kvm_proble_feature_msr(i);
> > - msr.index = msr_based_features_all[i];
> > - if (kvm_get_msr_feature(&msr))
> > - continue;
> > -
> > - msr_based_features[num_msr_based_features++] = msr_based_features_all[i];
> > - }
> > + for (i = 0; i < ARRAY_SIZE(msr_based_features_all_except_vmx); i++)
> > + kvm_proble_feature_msr(msr_based_features_all_except_vmx[i]);
>
> I'd rather move all the code to a new function kvm_init_feature_msr_list()
> instead, and call it from kvm_arch_hardware_setup().

Would it make sense to also split out kvm_init_emulated_msr_list()? Hmm, and
rename this to kvm_init_virtualized_msr_list()? I can't tell if that would be
helpful or confusing.