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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.54.1 (3.54.1-1.fc41) MIME-Version: 1.0 X-Stat-Signature: 5n68pyf7zf3gjyuifhqwpe9p5qak6moy X-Rspam-User: X-Rspamd-Queue-Id: 5EFC8180018 X-Rspamd-Server: rspam08 X-HE-Tag: 1736962888-552106 X-HE-Meta: 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 79WC/OPv pjc1L7MBcsCyGOdPl99RZ0FtY/+Xny3feo+/+3H0SfvE4iccSPw6w3MEDK5lC+Mbf1oYa1wxKY9/zTjT0LdQh5EgbL7a2lwNonlvb/tVF0Z9N4II2aRWqbrZsVGPko97RNpflw04zmlPw4yvGthUyLd8tOxhNTxrJhEagP7yUqo7Mm0St3T6MtY1cPyVlp/NL0pHVfZF06mqwiRuRKGOQ9cwRDJNYcEujzSFQA64aujPg3srX/fCip8ag+l8R+tDW7jqjEBl+Wxrb2Xw= 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: List-Subscribe: List-Unsubscribe: On Tue, 2025-01-14 at 20:42 +0100, Michal Hocko wrote: > O > I do agreee that a memory deadlock is not really proper way to deal > with > the issue. I have to admit that my understanding was based on ENOMEM > being properly propagated out of in kernel user page faults.=20 It looks like it kind of is. In case of VM_FAULT_OOM, the page fault code calls kernelmode_fixup_or_oops(), which a few functions down calls ex_handler_default(), which advances regs->ip to the next instruction after the one that faulted. Of course, if we have a copy_from_user loop, we could end up there a bunch of times :) --=20 All Rights Reversed.