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Subject: Re: [RFC 6/7] KVM: X86: Expose PKS to guest and userspace
To:     Jim Mattson <jmattson@google.com>,
        Sean Christopherson <seanjc@google.com>
Cc:     Chenyi Qiang <chenyi.qiang@intel.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Joerg Roedel <joro@8bytes.org>,
        Xiaoyao Li <xiaoyao.li@intel.com>,
        kvm list <kvm@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
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From:   Paolo Bonzini <pbonzini@redhat.com>
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Date:   Tue, 26 Jan 2021 19:24:50 +0100
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On 30/09/20 06:36, Sean Christopherson wrote:
>> CR4.PKS is not in the list of CR4 bits that result in a PDPTE load.
>> Since it has no effect on PAE paging, I would be surprised if it did
>> result in a PDPTE load.
> It does belong in the mmu_role_bits though;-)
> 

Does it?  We don't support PKU/PKS for shadow paging, and it's always 
zero for EPT.  We only support enough PKU/PKS for emulation.

Paolo