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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: B6C2740023 X-Stat-Signature: ukbbqyai4my5pnmyyyjqpafz7czm4ian X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1680509736-228614 X-HE-Meta: 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 KiXXXWZY 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 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 Sun 02-04-23 19:48:29, Tetsuo Handa wrote: > syzbot is reporting circular locking dependency which involves > zonelist_update_seq seqlock, for zonelist_update_seq is checked > while doing GFP_ATOMIC allocation. Could you explain the the deadlock scenario? > Since zonelist_update_seq is checked for avoiding unnecessary OOM kill, > there is no need to check zonelist_update_seq for memory allocations > which will fail without OOM kill. > > Therefore, let's keep locking dependency simple, by not checking > zonelist_update_seq from !__GFP_DIRECT_RECLAIM allocations. > > Reported-by: syzbot Is this https://lore.kernel.org/all/0000000000001d74d205f7c1821f@google.com/ the underlying report ? > Link: https://syzkaller.appspot.com/bug?extid=223c7461c58c58a4cb10 > Fixes: 3d36424b3b58 ("mm/page_alloc: fix race condition between build_all_zonelists and page allocation") > Signed-off-by: Tetsuo Handa -- Michal Hocko SUSE Labs