Re: [PATCH v10 22/50] KVM: SEV: Add GHCB handling for Hypervisor Feature Support requests

[Borislav Petkov]

On Mon, Oct 16, 2023 at 08:27:51AM -0500, Michael Roth wrote:
> diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
> index 4f895a7201ed..088b32657f46 100644
> --- a/arch/x86/kvm/svm/sev.c
> +++ b/arch/x86/kvm/svm/sev.c
> @@ -2568,6 +2568,7 @@ static int sev_es_validate_vmgexit(struct vcpu_svm *svm)
>  	case SVM_VMGEXIT_AP_HLT_LOOP:
>  	case SVM_VMGEXIT_AP_JUMP_TABLE:
>  	case SVM_VMGEXIT_UNSUPPORTED_EVENT:
> +	case SVM_VMGEXIT_HV_FEATURES:
>  		break;
>  	default:
>  		reason = GHCB_ERR_INVALID_EVENT;
> @@ -2828,6 +2829,13 @@ static int sev_handle_vmgexit_msr_protocol(struct vcpu_svm *svm)
>  				  GHCB_MSR_INFO_MASK,
>  				  GHCB_MSR_INFO_POS);
>  		break;
> +	case GHCB_MSR_HV_FT_REQ: {
				^^^

No need to have a statement block here. Neither below.


> +		set_ghcb_msr_bits(svm, GHCB_HV_FT_SUPPORTED,
> +				  GHCB_MSR_HV_FT_MASK, GHCB_MSR_HV_FT_POS);
> +		set_ghcb_msr_bits(svm, GHCB_MSR_HV_FT_RESP,
> +				  GHCB_MSR_INFO_MASK, GHCB_MSR_INFO_POS);
> +		break;
> +	}
>  	case GHCB_MSR_TERM_REQ: {
>  		u64 reason_set, reason_code;
>  
> @@ -2952,6 +2960,12 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu)
>  		ret = 1;
>  		break;
>  	}
> +	case SVM_VMGEXIT_HV_FEATURES: {
				      ^^^^

> +		ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_HV_FT_SUPPORTED);
> +
> +		ret = 1;
> +		break;
> +	}
>  	case SVM_VMGEXIT_UNSUPPORTED_EVENT:
>  		vcpu_unimpl(vcpu,
>  			    "vmgexit: unsupported event - exit_info_1=%#llx, exit_info_2=%#llx\n",

-- 
Regards/Gruss,
    Boris.

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