Re: [PATCH] KVM: VMX: simplify NMI mask management

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2011-03-23 15:58, Avi Kivity wrote:
> On 03/23/2011 04:54 PM, Jan Kiszka wrote:
>>>  @@ -3991,9 +3987,7 @@ static void __vmx_complete_interrupts(struct vcpu_vmx *vmx,
>>>   		* Clear bit "block by NMI" before VM entry if a NMI
>>>   		* delivery faulted.
>>>   		*/
>>>  -		vmcs_clear_bits(GUEST_INTERRUPTIBILITY_INFO,
>>>  -				GUEST_INTR_STATE_NMI);
>>>  -		vmx->nmi_known_unmasked = true;
>>>  +		vmx_set_nmi_mask(&vmx->vcpu, false);
>>>   		break;
>>>   	case INTR_TYPE_SOFT_EXCEPTION:
>>>   		vmx->vcpu.arch.event_exit_inst_len =
>>
>> Looks consistent to me, but maybe you should update the comment above
>> that's now also applied to the emulated mask.
> 
> In what way?
> 
>          /*
>           * SDM 3: 27.7.1.2 (September 2008)
>           * Clear bit "block by NMI" before VM entry if a NMI
>           * delivery faulted.
>           */
> 
> Seems pretty descriptive.

IIRC, the above only applies to CPUs that support VNMI and is
meaningless for older ones. But vmx_set_nmi_mask is not void for those
old CPUs.

Jan

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