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Subject: Re: [PATCH v5 03/15] KVM: SVM: Disable SEV/SEV-ES if NPT is disabled
To:     Sean Christopherson <seanjc@google.com>
Cc:     Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Wei Huang <wei.huang2@amd.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Borislav Petkov <bp@suse.de>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        Brijesh Singh <brijesh.singh@amd.com>
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From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <0a00ee34-965a-0ee1-1e2c-7fda8e21ec9e@redhat.com>
Date:   Fri, 23 Apr 2021 09:08:55 +0200
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On 22/04/21 20:11, Sean Christopherson wrote:
>> Yes, you're right.  NPT is easy but we would have to guess what the spec
>> would say about MAXPHYADDR, while nNPT would require the stacking of a PML5.
>> Either way, blocking KVM is the easiest thing todo.
> How about I fold that into the s/lm_root/pml4_root rename[*]?  I.e. make the
> blocking of PML5 a functional change, and the rename an opportunistic change?
> 
> [*]https://lkml.kernel.org/r/20210318201131.3242619-1-seanjc@google.com
> 

Yes, that's a good plan.  Thanks,

Paolo