> >+ case MSR_IA32_FRED_RSP0 ... MSR_IA32_FRED_CONFIG: > >+ /* FRED MSRs should be passthrough to FRED guests only */ > > This comment sounds weird. It sounds like the code will be something like: > if guest supports FRED > return true > else > return false > > how about "FRED MSRs are pass-thru'd to guests which enumerate FRED"? > > Or to align with above comment for LBR MSRs, just say > > /* FRED MSRs. These are handled in vmx_vcpu_config_fred_after_set_cpuid() */ > Maybe both to not confuse people at all 😊 > >+ return true; > > } > > > > r = possible_passthrough_msr_slot(msr) != -ENOENT; @@ -7774,10 > >+7777,12 @@ static void update_intel_pt_cfg(struct kvm_vcpu *vcpu) > >static void vmx_vcpu_config_fred_after_set_cpuid(struct kvm_vcpu *vcpu) > >{ > > struct vcpu_vmx *vmx = to_vmx(vcpu); > >+ bool fred_enumerated; > > > > kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_FRED); > >+ fred_enumerated = guest_can_use(vcpu, X86_FEATURE_FRED); > > > >- if (guest_can_use(vcpu, X86_FEATURE_FRED)) { > >+ if (fred_enumerated) { > > vm_entry_controls_setbit(vmx, VM_ENTRY_LOAD_IA32_FRED); > > secondary_vm_exit_controls_setbit(vmx, > > > SECONDARY_VM_EXIT_SAVE_IA32_FRED | @@ -7788,6 +7793,16 @@ > >static void vmx_vcpu_config_fred_after_set_cpuid(struct kvm_vcpu *vcpu) > > > SECONDARY_VM_EXIT_SAVE_IA32_FRED | > > > SECONDARY_VM_EXIT_LOAD_IA32_FRED); > > } > >+ > >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_RSP0, > MSR_TYPE_RW, !fred_enumerated); > >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_RSP1, > MSR_TYPE_RW, !fred_enumerated); > >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_RSP2, > MSR_TYPE_RW, !fred_enumerated); > >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_RSP3, > MSR_TYPE_RW, !fred_enumerated); > >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_STKLVLS, > MSR_TYPE_RW, !fred_enumerated); > >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_SSP1, > MSR_TYPE_RW, !fred_enumerated); > >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_SSP2, > MSR_TYPE_RW, !fred_enumerated); > >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_SSP3, > MSR_TYPE_RW, !fred_enumerated); > >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_CONFIG, MSR_TYPE_RW, > >+!fred_enumerated); > > Use a for-loop here? e.g., > for (i = MSR_IA32_FRED_RSP0; i <= MSR_IA32_FRED_CONFIG; i++) > > } Yeah, let me try.