Re: [PATCH] KVM: MMU: shadow nested paging does not have PKU

On 11/27/21 4:25 AM, Paolo Bonzini wrote:

On 11/27/21 02:21, Lai Jiangshan wrote:

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On 2021/11/26 21:21, Paolo Bonzini wrote:

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Initialize the mask for PKU permissions as if CR4.PKE=0, avoiding incorrect interpretations of the nested hypervisor's page tables.

I think the AMD64 volume2 Architecture Programmer’s Manual does not specify it, but it seems that for a sane NPT walk, PKU should not work in NPT.

The PK bit is not defined in the nested page fault EXITINFO1, too. Thomas, can you have it fixed in the APM that the host's SMEP, SMAP and PKE bits do not affect nested page table walks?

I talked to our documentation folks and they will look to update the APM with the appropriate information.

Thanks, Tom