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Message-ID: <5f2f0a44fbb1a2eab36183dfc2fcaf53e1109793.camel@linux.intel.com>
Subject: Re: [PATCH v3 2/9] KVM: x86: Add CR4.LAM_SUP in guest owned bits
From:   Robert Hoo <robert.hu@linux.intel.com>
To:     Sean Christopherson <seanjc@google.com>
Cc:     pbonzini@redhat.com, kirill.shutemov@linux.intel.com,
        kvm@vger.kernel.org, Jingqi Liu <jingqi.liu@intel.com>
Date:   Sat, 07 Jan 2023 21:32:50 +0800
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On Sat, 2023-01-07 at 00:38 +0000, Sean Christopherson wrote:
> On Fri, Dec 09, 2022, Robert Hoo wrote:
> > If LAM enabled, CR4.LAM_SUP is owned by guest; otherwise, reserved.
> 
> Why is it passed through to the guest?

I think no need to intercept guest's control over CR4.LAM_SUP, which
controls LAM appliance to supervisor mode address.

Same pass-through happens to CR3.LAM_U{48, 57} when EPT is effective.