Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <e09dae40-d269-cfed-d048-3e62275c1bb7@intel.com>
Date:   Fri, 24 Jun 2022 10:09:24 -0700
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101
 Thunderbird/91.9.1
Subject: Re: [PATCHv7 00/14] mm, x86/cc: Implement support for unaccepted
 memory
Content-Language: en-US
To:     Marc Orr <marcorr@google.com>
Cc:     Peter Gonda <pgonda@google.com>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Borislav Petkov <bp@alien8.de>,
        Andy Lutomirski <luto@kernel.org>,
        Sean Christopherson <seanjc@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Joerg Roedel <jroedel@suse.de>,
        Ard Biesheuvel <ardb@kernel.org>,
        Andi Kleen <ak@linux.intel.com>,
        Kuppuswamy Sathyanarayanan 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        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>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Ingo Molnar <mingo@redhat.com>,
        Varad Gautam <varad.gautam@suse.com>,
        Dario Faggioli <dfaggioli@suse.com>,
        Mike Rapoport <rppt@kernel.org>,
        David Hildenbrand <david@redhat.com>,
        Marcelo <marcelo.cerri@canonical.com>, tim.gardner@canonical.com,
        Khalid ElMously <khalid.elmously@canonical.com>,
        philip.cox@canonical.com,
        the arch/x86 maintainers <x86@kernel.org>,
        linux-mm@kvack.org, linux-coco@lists.linux.dev,
        linux-efi@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>
References: <20220614120231.48165-1-kirill.shutemov@linux.intel.com>
 <CAMkAt6osbEGBFrgn=y1=x4mDHC1aL40BwaW0NdGHF8qmWd7ktA@mail.gmail.com>
 <5af19000-4482-7eb9-f158-0a461891f087@intel.com>
 <CAA03e5F480=psSECDAkXQEvNKk3une-4dJV57Hde4z4MMzh=1A@mail.gmail.com>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <CAA03e5F480=psSECDAkXQEvNKk3une-4dJV57Hde4z4MMzh=1A@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 6/24/22 10:06, Marc Orr wrote:
> I think Peter's point is a little more nuanced than that. Once lazy
> accept goes into the guest firmware -- without the feature negotiation
> that Peter is suggesting -- cloud providers now have a bookkeeping
> problem. Which images have kernels that can boot from a guest firmware
> that doesn't pre-validate all the guest memory?

Hold on a sec though...

Is this a matter of

	can boot from a guest firmware that doesn't pre-validate all the
	guest memory?

or

	can boot from a guest firmware that doesn't pre-validate all the
	guest memory ... with access to all of that guest's RAM?

In other words, are we talking about "fails to boot" or "can't see all
the RAM"?