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Date:   Tue, 28 Jun 2022 17:10:56 -0700
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Subject: Re: [PATCHv7 11/14] x86: Disable kexec if system has unaccepted
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To:     "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        "Eric W. Biederman" <ebiederm@xmission.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,
        x86@kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev,
        linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org,
        kexec@lists.infradead.org
References: <20220614120231.48165-1-kirill.shutemov@linux.intel.com>
 <20220614120231.48165-12-kirill.shutemov@linux.intel.com>
 <6be29d38-5c93-7cc9-0de7-235d3f83773c@intel.com>
 <87a6a3aw50.fsf@email.froward.int.ebiederm.org>
 <20220624020005.txpxlsbjbebf6oq4@black.fi.intel.com>
 <20220628235105.z6ytdzxofrdkjti4@black.fi.intel.com>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <20220628235105.z6ytdzxofrdkjti4@black.fi.intel.com>
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On 6/28/22 16:51, Kirill A. Shutemov wrote:
> On Fri, Jun 24, 2022 at 05:00:05AM +0300, Kirill A. Shutemov wrote:
>>> If there is some deep and fundamental why this can not be supported
>>> then it probably makes sense to put some code in the arch_kexec_load
>>> hook that verifies that deep and fundamental reason is present.
...
> +	/*
> +	 * TODO: Information on memory acceptance status has to be communicated
> +	 * between kernel.
> +	 */

So, the deep and fundamental reason is... drum roll... you haven't
gotten around to implementing bitmap passing yet?!?!?   I have the
feeling that wasn't what Eric was looking for.