Re: [PATCH v3 2/5] KVM: MMU: check guest CR3 reserved bits based on its physical address width.

From: Paolo Bonzini
Date: Thu Aug 24 2017 - 12:27:55 EST


On 24/08/2017 17:38, Yu Zhang wrote:
>>
>>
>> In practice, MAXPHYADDR will never be 59 even because the PKRU bits are
>> at bits 59..62.
>
> Thanks, Paolo.
> I see. I had made an assumption that MAXPHYADDR shall not exceed the
> physical one,
> which is 52 I believe. But I'm not sure there's any place to check this.
> Maybe we should make sure the vcpu->arch.maxphyaddr will not be greater
> than the value of the host?

That's a separate change anyway. In any case, since currently the
MAXPHYADDR is not validated, your change to rsvd_bits makes sense.

Paolo