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Subject: Re: [RFC] KVM: mm: fd-based approach for supporting KVM guest private
 memory
To:     Andi Kleen <ak@linux.intel.com>,
        Yu Zhang <yu.c.zhang@linux.intel.com>
Cc:     Sean Christopherson <seanjc@google.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>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Borislav Petkov <bp@alien8.de>,
        Andy Lutomirski <luto@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Joerg Roedel <jroedel@suse.de>,
        David Rientjes <rientjes@google.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Varad Gautam <varad.gautam@suse.com>,
        Dario Faggioli <dfaggioli@suse.com>, x86@kernel.org,
        linux-mm@kvack.org, linux-coco@lists.linux.dev,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        "Kirill A . Shutemov" <kirill@shutemov.name>,
        Kuppuswamy Sathyanarayanan 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        Dave Hansen <dave.hansen@intel.com>
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 <243bc6a3-b43b-cd18-9cbb-1f42a5de802f@redhat.com>
 <765e9bbe-2df5-3dcc-9329-347770dc091d@linux.intel.com>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
Message-ID: <4677f310-5987-0c13-5caf-fd3b625b4344@redhat.com>
Date:   Tue, 31 Aug 2021 22:15:40 +0200
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On 31.08.21 22:01, Andi Kleen wrote:
> 
>>> Thanks a lot for this summary. A question about the requirement: do
>>> we or
>>> do we not have plan to support assigned device to the protected VM?
>>
>> Good question, I assume that is stuff for the far far future.
> 
> It is in principle possible with the current TDX, but not secure. But
> someone might decide to do it. So it would be good to have basic support
> at least.

Can you elaborate the "not secure" part? Do you mean, making the device 
only access "shared" memory, not secure/encrypted/whatsoever?

-- 
Thanks,

David / dhildenb