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Subject: Re: [PATCH v2 1/3] KVM: x86: Allow CPU to force vendor-specific TDP
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From:   Paolo Bonzini <pbonzini@redhat.com>
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Date:   Tue, 10 Aug 2021 14:47:27 +0200
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On 10/08/21 13:00, Yu Zhang wrote:
> I guess it's because, unlike EPT which are with either 4 or 5 levels, NPT's
> level can range from 2 to 5, depending on the host paging mode...

Yes, on Linux that will be one of 3/4/5 based on host paging mode, and 
it will apply to all N_CR3...

> But shadow EPT does not have such annoyance. Is above understanding correct?

... Right, because shadow EPT cannot have less than 4 levels, and it can 
always use 4 levels if that's what L1 uses.

Paolo