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Date:   Fri, 24 Jun 2022 09:57:14 -0700
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Subject: Re: [PATCHv7 00/14] mm, x86/cc: Implement support for unaccepted
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To:     Peter Gonda <pgonda@google.com>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc:     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.cerri@canonical.com, tim.gardner@canonical.com,
        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>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <CAMkAt6osbEGBFrgn=y1=x4mDHC1aL40BwaW0NdGHF8qmWd7ktA@mail.gmail.com>
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Peter, is your enter key broken?  You seem to be typing all your text in
a single unreadable paragraph.

On 6/24/22 09:37, Peter Gonda wrote:
> if a customer incorrectly labels their image it may fail to boot..

You're saying that firmware basically has two choices:
1. Accept all the memory up front and boot slowly, but reliably
2. Use thus "unaccepted memory" mechanism, boot fast, but risk that the
   VM loses a bunch of memory.

If the guest can't even boot because of a lack of memory, then the
pre-accepted chunk is probably too small in the first place.

If the customer screws up, they lose a bunch of the RAM they paid for.
That seems like a rather self-correcting problem to me.