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Received: from viro by zeniv.linux.org.uk with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1uo4Yi-000000078b6-0d8k; Mon, 18 Aug 2025 18:26:16 +0000 Date: Mon, 18 Aug 2025 19:26:16 +0100 From: Al Viro To: syzbot Cc: andrii@kernel.org, ast@kernel.org, bigeasy@linutronix.de, bpf@vger.kernel.org, brauner@kernel.org, daniel@iogearbox.net, davem@davemloft.net, eddyz87@gmail.com, edumazet@google.com, haoluo@google.com, jack@suse.cz, jiri@resnulli.us, john.fastabend@gmail.com, jolsa@kernel.org, kerneljasonxing@gmail.com, kpsingh@kernel.org, kuba@kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, martin.lau@linux.dev, netdev@vger.kernel.org, pabeni@redhat.com, sdf@fomichev.me, song@kernel.org, syzkaller-bugs@googlegroups.com, tglx@linutronix.de, yonghong.song@linux.dev Subject: Re: [syzbot] [mm?] INFO: rcu detected stall in sys_umount (3) Message-ID: <20250818182616.GB222315@ZenIV> References: <67555b72.050a0220.2477f.0026.GAE@google.com> <68a2f584.050a0220.e29e5.009d.GAE@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <68a2f584.050a0220.e29e5.009d.GAE@google.com> Sender: Al Viro On Mon, Aug 18, 2025 at 02:42:28AM -0700, syzbot wrote: > syzbot has found a reproducer for the following issue on: > > HEAD commit: 8f5ae30d69d7 Linux 6.17-rc1 > git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci > console output: https://syzkaller.appspot.com/x/log.txt?x=1321eba2580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=8c5ac3d8b8abfcb > dashboard link: https://syzkaller.appspot.com/bug?extid=1ec0f904ba50d06110b1 > compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7 > userspace arch: arm64 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10cba442580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10a1eba2580000 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/18a2e4bd0c4a/disk-8f5ae30d.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/3b5395881b25/vmlinux-8f5ae30d.xz > kernel image: https://storage.googleapis.com/syzbot-assets/e875f4e3b7ff/Image-8f5ae30d.gz.xz > mounted in repro: https://storage.googleapis.com/syzbot-assets/43186d9e448c/mount_0.gz > fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=174ba442580000) > > The issue was bisected to: > > commit d15121be7485655129101f3960ae6add40204463 > Author: Paolo Abeni > Date: Mon May 8 06:17:44 2023 +0000 > > Revert "softirq: Let ksoftirqd do its job" Would be interesting to see how it behaves on git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git #fixes (cda250b0fc83)