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Wed, 12 Aug 2026 21:41:54 +0000 X-Migadu-Flow: FLOW_OUT Date: Wed, 12 Aug 2026 14:41:49 -0700 From: Shakeel Butt To: Andrew Morton Cc: syzbot , axelrasmussen@google.com, baohua@kernel.org, baolin.wang@linux.alibaba.com, cgroups@vger.kernel.org, david@kernel.org, hannes@cmpxchg.org, kasong@tencent.com, kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ljs@kernel.org, mhocko@kernel.org, mhocko@suse.com, muchun.song@linux.dev, qi.zheng@linux.dev, roman.gushchin@linux.dev, syzkaller-bugs@googlegroups.com, weixugc@google.com, yuanchu@google.com Subject: Re: [syzbot] [mm?] WARNING in set_mm_walk Message-ID: References: <6a7a6929.b50370da.49fe0.005e.GAE@google.com> <6a7c6670.3668565d.e8814.0012.GAE@google.com> <20260812140358.343927ad8d0955b67c4e7ad5@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260812140358.343927ad8d0955b67c4e7ad5@linux-foundation.org> X-Rspam-User: X-Stat-Signature: wjstw1a7q5dadfzjk14n9ay1otddteqt X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 283C580003 X-HE-Tag: 1786570915-795094 X-HE-Meta: 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 zo9G+4Ml 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Aug 12, 2026 at 02:03:58PM -0700, Andrew Morton wrote: > On Wed, 12 Aug 2026 05:26:24 -0700 syzbot wrote: > > > syzbot has found a reproducer for the following issue on: > > > > HEAD commit: f5bbbfec59b4 Merge tag 'probes-fixes-v7.2-rc7' of git://gi.. > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=11f44c79580000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=c44651ea7dd2f307 > > dashboard link: https://syzkaller.appspot.com/bug?extid=12ee2725d5fde63a9c96 > > compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10d11149580000 > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > Reported-by: syzbot+12ee2725d5fde63a9c96@syzkaller.appspotmail.com > > > > ------------[ cut here ]------------ > > current_is_kswapd() > > WARNING: mm/vmscan.c:3800 at set_mm_walk+0x210/0x270 mm/vmscan.c:3800, CPU#2: kswapd0/111 > > Thanks. Shakeel is working on a series which will fix this by removing > the calling code. But it isn't a minor patch. > > Shakeel, it would be good to have a backportable quick-fix to make this > warning go away? > Actually the first patch [1] of the series will fix this warning and we can backport just that patch to the older stable kernels. Do you want me to send that patch as a standalone? [1] https://lore.kernel.org/all/20260811203203.3456029-2-shakeel.butt@linux.dev/