From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 671313A6B9C for ; Tue, 18 Aug 2026 11:50:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787053840; cv=none; b=Jc5HSH4lSPFao/X78Jd/h6D4Ym5DgsDqYM8YtpVi5ic31/Lc9bI2dAidE7A5sQjyMPPGQ/2a7UbsQnoiZDmEAF05mDB1yzn4tqM6qfQr6iJHMe1sRVyj2VRdPH9atdmUeBdLJgl5Vwe4oZwLoD/GEOHY6I4yy7rdxT8tF8SVmXw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787053840; c=relaxed/simple; bh=mYRttp5pKqhM9dKMD4crfS04x24Kq84DJOydDHnXwA4=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=iXchkUOm1tVeF1WHXN5FOeUH/XwucYlGpUlyXQDAwm0Ek4URbBmRQmRGSmOScennLM6bbSOmNOf3Nbbmx7Uk97+ALMSnHwFCiBH3EBXcG0kTpPXBWtzRCO9uS/Db4FEy7Ql+0cMaFcj7MMekizteuJgBgoosVA0+SWPtyQSAqL4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=U1xOEDh+; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="U1xOEDh+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1B4D11F000E9; Tue, 18 Aug 2026 11:50:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787053839; bh=Z9b5XXuybQ7GI+3Z2/bQurGayFuYmB1m5lZSagDKMcU=; h=Date:Cc:Subject:To:References:From:In-Reply-To; b=U1xOEDh+QxbsjGPMT7UcyO02InVuQwtioOAzzUJMDx0QSMxkvB/Nz+57+0e9fBSCh HJJmgVUscYoditRDj9DG1KEUjc9qvkjQBo3+H6oyjLwvFqgjkA+Q2091eoy0ca/Gcd KjESm/9rOBu7xsBrbSabDGo5XuHSxll1NjkyZzFGvYspNki9hm48waTYQ5CevcP/2p S3gYdp3XUHRhxCdYNuOQg+mTUM6BxGAw1Ma4dK17fDI+k6OYsLoFOoGfgZKFK8JxnQ 1phpE/jZyOuWanPJPzeewdv+9NBBW7De2R0H0pnMe1/70SXy9yBb7ZimHPmEACHM2p 3RqzO7vQ8Zk4w== Message-ID: <40fef665-0a29-4c44-9ce0-e02e6dc8d07b@kernel.org> Date: Tue, 18 Aug 2026 19:50:36 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: chao@kernel.org Subject: Re: [syzbot] [f2fs?] WARNING: suspicious RCU usage in __f2fs_add_ino_entry To: syzbot , jaegeuk@kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com References: <6a834262.4d75e56a.c9a88.0002.GAE@google.com> Content-Language: en-US From: Chao Yu In-Reply-To: <6a834262.4d75e56a.c9a88.0002.GAE@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit #syz test: https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git bugfix/common On 8/18/26 01:18, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: 4477a78374a5 Add linux-next specific files for 20260814 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=150bea25580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=9b32a36dd637b06f > dashboard link: https://syzkaller.appspot.com/bug?extid=014a7b70788139e6196d > compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12d3fa79580000 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/994c1c8c560e/disk-4477a783.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/cd54543d69ae/vmlinux-4477a783.xz > kernel image: https://storage.googleapis.com/syzbot-assets/407cdf8f3fc2/bzImage-4477a783.xz > mounted in repro: https://storage.googleapis.com/syzbot-assets/12687adce9ef/mount_0.gz > fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=171cd949580000) > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+014a7b70788139e6196d@syzkaller.appspotmail.com > > ============================= > WARNING: suspicious RCU usage > syzkaller #0 Not tainted > ----------------------------- > ./include/linux/radix-tree.h:179 suspicious rcu_dereference_check() usage! > > other info that might help us debug this: > > > rcu_scheduler_active = 2, debug_locks = 1 > locks held by kworker/u9:3/5775: 4, last CPU#0: > #0: ffff88807f597940 ((wq_completion)f2fs_evict_wq){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] > #0: ffff88807f597940 ((wq_completion)f2fs_evict_wq){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] > #0: ffff88807f597940 ((wq_completion)f2fs_evict_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3352 [inline] > #0: ffff88807f597940 ((wq_completion)f2fs_evict_wq){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3470 > #1: ffffc90003fb7c40 ((work_completion)(&ew->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] > #1: ffffc90003fb7c40 ((work_completion)(&ew->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] > #1: ffffc90003fb7c40 ((work_completion)(&ew->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3352 [inline] > #1: ffffc90003fb7c40 ((work_completion)(&ew->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3470 > #2: ffff8880b863a820 (lock){+.+.}-{3:3}, at: local_lock_acquire include/linux/local_lock_internal.h:46 [inline] > #2: ffff8880b863a820 (lock){+.+.}-{3:3}, at: __radix_tree_preload+0x82/0x870 lib/radix-tree.c:334 > #3: ffff8880338688c8 (&im->ino_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:347 [inline] > #3: ffff8880338688c8 (&im->ino_lock){+.+.}-{3:3}, at: __set_ino_bitmap fs/f2fs/checkpoint.c:781 [inline] > #3: ffff8880338688c8 (&im->ino_lock){+.+.}-{3:3}, at: __f2fs_add_ino_entry+0x14c/0x830 fs/f2fs/checkpoint.c:842 > > stack backtrace: > CPU: 0 UID: 0 PID: 5775 Comm: kworker/u9:3 Not tainted syzkaller #0 PREEMPT(full) > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 > Workqueue: f2fs_evict_wq f2fs_evict_inode_work > Call Trace: > > dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 > lockdep_rcu_suspicious+0x140/0x1d0 kernel/locking/lockdep.c:6938 > radix_tree_deref_slot include/linux/radix-tree.h:179 [inline] > __set_ino_bitmap fs/f2fs/checkpoint.c:784 [inline] > __f2fs_add_ino_entry+0x782/0x830 fs/f2fs/checkpoint.c:842 > f2fs_record_inode_state fs/f2fs/inode.c:877 [inline] > f2fs_evict_inode_work+0xa1/0x120 fs/f2fs/inode.c:887 > process_one_work kernel/workqueue.c:3387 [inline] > process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470 > worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551 > kthread+0x38b/0x480 kernel/kthread.c:436 > ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 > > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@googlegroups.com. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > > If the report is already addressed, let syzbot know by replying with: > #syz fix: exact-commit-title > > If you want syzbot to run the reproducer, reply with: > #syz test: git://repo/address.git branch-or-commit-hash > If you attach or paste a git patch, syzbot will apply it before testing. > > If you want to overwrite report's subsystems, reply with: > #syz set subsystems: new-subsystem > (See the list of subsystem names on the web dashboard) > > If the report is a duplicate of another one, reply with: > #syz dup: exact-subject-of-another-report > > If you want to undo deduplication, reply with: > #syz undup