Re: [PATCH v10 100/108] KVM: TDX: Handle TDX PV report fatal error hypercall

[Binbin Wu]

On 10/30/2022 2:23 PM, isaku.yamahata@xxxxxxxxx wrote:
> From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
>
> Wire up TDX PV report fatal error hypercall to KVM_SYSTEM_EVENT_CRASH KVM
> exit event.
>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
> ---
>   arch/x86/kvm/vmx/tdx.c   | 20 ++++++++++++++++++++
>   include/uapi/linux/kvm.h |  1 +
>   2 files changed, 21 insertions(+)
>
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index e3062c245e70..16f168f4f21a 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -1068,6 +1068,24 @@ static int tdx_emulate_wrmsr(struct kvm_vcpu *vcpu)
>   	return 1;
>   }
>   
> +static int tdx_report_fatal_error(struct kvm_vcpu *vcpu)
> +{
> +	/*
> +	 * Exit to userspace device model for teardown.
> +	 * Because guest TD is already panicing

panicking


> , returning an error to guerst

typo, guest



>   TD
> +	 * doesn't make sense.  No argument check is done.
> +	 */
> +
> +	vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
> +	vcpu->run->system_event.type = KVM_SYSTEM_EVENT_TDX;
> +	vcpu->run->system_event.ndata = 3;
> +	vcpu->run->system_event.data[0] = TDG_VP_VMCALL_REPORT_FATAL_ERROR;
> +	vcpu->run->system_event.data[1] = tdvmcall_a0_read(vcpu);
> +	vcpu->run->system_event.data[2] = tdvmcall_a1_read(vcpu);
> +
> +	return 0;
> +}
> +
>   static int handle_tdvmcall(struct kvm_vcpu *vcpu)
>   {
>   	if (tdvmcall_exit_type(vcpu))
> @@ -1086,6 +1104,8 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu)
>   		return tdx_emulate_rdmsr(vcpu);
>   	case EXIT_REASON_MSR_WRITE:
>   		return tdx_emulate_wrmsr(vcpu);
> +	case TDG_VP_VMCALL_REPORT_FATAL_ERROR:
> +		return tdx_report_fatal_error(vcpu);
>   	default:
>   		break;
>   	}
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 49386e4de8b8..504a8f73284b 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -478,6 +478,7 @@ struct kvm_run {
>   #define KVM_SYSTEM_EVENT_WAKEUP         4
>   #define KVM_SYSTEM_EVENT_SUSPEND        5
>   #define KVM_SYSTEM_EVENT_SEV_TERM       6
> +#define KVM_SYSTEM_EVENT_TDX            7
>   			__u32 type;
>   			__u32 ndata;
>   			union {