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Date:   Sat, 7 Aug 2021 10:24:23 +1200
From:   Kai Huang <kai.huang@intel.com>
To:     Sean Christopherson <seanjc@google.com>
Cc:     isaku.yamahata@intel.com, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, erdemaktas@google.com,
        Connor Kuehl <ckuehl@redhat.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        isaku.yamahata@gmail.com,
        Rick Edgecombe <rick.p.edgecombe@intel.com>
Subject: Re: [RFC PATCH v2 41/69] KVM: x86: Add infrastructure for stolen
 GPA bits
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On Fri, 6 Aug 2021 22:09:35 +0000 Sean Christopherson wrote:
> On Sat, Aug 07, 2021, Kai Huang wrote:
> > So could we have your final suggestion? :)
> 
> Try the kvm_mmu_page_role.private approach.  So long as it doesn't end up splattering
> code everywhere, I think that's more aligned with how KVM generally wants to treat
> the shared bit.

OK.

> 
> In the changelog for this patch, make it very clear that ensuring different aliases
> get different shadow page (if necessary) is the responsiblity of each individual
> feature that leverages stolen gfn bits.

Make sense.  Thanks.