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Shutemov" , Borislav Petkov , Andrew Morton , Ard Biesheuvel Cc: Dave Hansen , Vlastimil Babka , Mike Rapoport , Lorenzo Stoakes , Tom Lendacky , Baoquan He , Vivek Goyal , Dave Young , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev, linux-efi@vger.kernel.org, kexec@lists.infradead.org References: <20230911112114.91323-1-adrian.hunter@intel.com> <20230911112114.91323-2-adrian.hunter@intel.com> <96f124d6-c1f2-adb3-1d3b-8329e85ff099@redhat.com> From: Adrian Hunter Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki In-Reply-To: <96f124d6-c1f2-adb3-1d3b-8329e85ff099@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Stat-Signature: ksdpqjr5hpkcada9s6xkpxs99durniaw X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 8ED22180007 X-Rspam-User: X-HE-Tag: 1694504881-504259 X-HE-Meta: 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 6fMaX6GM JLihY1fuvf4STilUh2/QHLBcTYh0tiFBSCxB/wd0ma9FnhM240u0XT2nAcyLKB7oFe5osAwo/y27+p5gqCxfMcDofsJfVaCSKBRyoDcJrnUywk59uAMJ12VkQ3x9VIj7UCcYMuxkg+cafW+O5fKgyK7lu1gDy2zTE1mDGwuRpV9j+HlAaXxvGdpoKXQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 12/09/23 10:19, David Hildenbrand wrote: > On 11.09.23 13:21, Adrian Hunter wrote: >> Support for unaccepted memory was added recently, refer commit dcdfdd40fa82 >> ("mm: Add support for unaccepted memory"), whereby a virtual machine may >> need to accept memory before it can be used. >> >> Do not let /proc/vmcore try to access unaccepted memory because it can >> cause the guest to fail. > > Oh, hold on. What are the actual side effects of this? > > Once we're in the kdump kernel, any guest is already dead. So failing a guest doesn't apply, no? > Unaccepted Memory is used by virtual machines. In this case the guest has kexec'ed to a dump-capture kernel, so the virtual machine is still alive and running the dump-capture kernel.