From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo2-f11.google.com (mail-oo2-f11.google.com [74.125.231.139]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 678CC1DD525 for ; Sat, 19 Sep 2026 15:58:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.231.139 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789833511; cv=none; b=qrcoLZwLoMhfyv8C0eTHVWaGybb3lAXdOQWRECmohS7tNyq/wauxSB75FTmQoDHvCEjXAP54RMMWbeRfZNorYCRPtZaQ+fBi7RAS6lLGpkEqTGQfur2WdmSWeyfrcFsrJIDswhz/2YBfkNnCYqXJJjb+81REx9QGs+mWcnHxjdo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789833511; c=relaxed/simple; bh=yovsU51vjkoZMx1hq4SJONBpy+r/mkAWfP48yuFB7Ks=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=kjCf/6BoWvligjRuTeyPtSiJNbGxW16PfD/xHcRngkToPeDonyc3Yn6RLggdIfwaAPpSuQsE8jYHCFp2Dezq5gxdxGQwNkewPDJEkcJbDADox8TGR7TkMpiDW5TdjFIjPRULnLdKoBLHn+yFMwP7UIxdv2EDhfCM2hN7vCNmFhs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=74.125.231.139 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oo2-f11.google.com with SMTP id 006d021491bc7-6aaf6076546so946460eaf.1 for ; Sat, 19 Sep 2026 08:58:29 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1789833508; x=1790438308; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=GXJsyqh43xC3K8WUE3/+Do/lplJCqQ+WF/KMqy1gCy8=; b=XNvRBTp/XPkxbmZBnEdUyep5LgDQoOic9hDaTij9HJC38rR5J4YMIutNZ94s2M+h72 H8rWMirqtJWJhDsy2gLbMHpcK+pyejoiiiifKQfnA/l/ltRDyzL6XGOOqVcVK/BjxvFD DePzHosPGT2kIvgEzRnXS1xYDjJNIwVQp5qHWSWI4Kf71nC3Bwe5H6vkzh/mXsSEkAx8 6G/t9XP0FGnMDlmJVisobKvHIvvqpTmTHjNx+3O6/PHh/ClZfTjX9WnJ8HDv1L/TD6Z/ viDxw/F4hsve4p25TDavWqiWA/VdPT9hlGWGTURDUia6xg+K3g4ACCOFSlQWRTIHhI2O S4Qw== X-Forwarded-Encrypted: i=1; AKwUvBxIVBtekYnFhVl4dy6INXVMep9bJVgA5KFBAIQagAmigmxGuwttcBQn6VrRGB720IxwFLEMV8AZZ5810lE=@vger.kernel.org X-Gm-Message-State: AFuF++kZol4TupIdD+dufg+WCPGXgrJp44DZrvFU9O4t5nJgsUSTQIMq vL4FF1iMUIb34KMMXrFQPMVXAaFKg9qNK6MfUFC0qrTCrklohjepVgokOwms40vO02N1f0iUdar OLBkUddcP5/j3YW+kfrof3S6FwT6X6cYEJ25AJGjh/3yPlPGUICTyEjvVEjI= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:208d:b0:6cd:3ffc:e328 with SMTP id 006d021491bc7-6cd3ffcea32mr2568408eaf.70.1789833508290; Sat, 19 Sep 2026 08:58:28 -0700 (PDT) Date: Sat, 19 Sep 2026 08:58:28 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6aaeb124.71f81b7d.15fa6d.000b.GAE@google.com> Subject: [syzbot] [ocfs2?] possible deadlock in ocfs2_nfs_sync_lock (3) From: syzbot To: jlbec@evilplan.org, joseph.qi@linux.alibaba.com, linux-kernel@vger.kernel.org, mark@fasheh.com, ocfs2-devel@lists.linux.dev, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 587858367581 Merge tag 'nfsd-7.3-1' of git://git.kernel.or.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=13496501580000 kernel config: https://syzkaller.appspot.com/x/.config?x=e909ffe6b35dddb7 dashboard link: https://syzkaller.appspot.com/bug?extid=a68ce48df87b8e36e915 compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-58785836.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/0d7169e6099c/vmlinux-58785836.xz kernel image: https://storage.googleapis.com/syzbot-assets/ced6ee748d49/bzImage-58785836.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a68ce48df87b8e36e915@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ kswapd0/70 is trying to acquire lock: ffff88800e994bc0 (&osb->nfs_sync_rwlock){.+.+}-{4:4}, at: ocfs2_nfs_sync_lock+0x106/0x270 fs/ocfs2/dlmglue.c:2875 but task is already holding lock: ffffffff8ee92540 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:7177 [inline] ffffffff8ee92540 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xa08/0x32c0 mm/vmscan.c:7555 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (fs_reclaim){+.+.}-{0:0}: __fs_reclaim_acquire mm/page_alloc.c:4375 [inline] fs_reclaim_acquire+0x71/0x100 mm/page_alloc.c:4389 might_alloc include/linux/sched/mm.h:316 [inline] slab_pre_alloc_hook mm/slub.c:4636 [inline] slab_alloc_node mm/slub.c:4974 [inline] __kmalloc_cache_noprof+0x61/0x600 mm/slub.c:5559 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] ocfs2_reserve_new_metadata_blocks+0x10c/0x9a0 fs/ocfs2/suballoc.c:1084 ocfs2_mknod+0xee4/0x22b0 fs/ocfs2/namei.c:356 ocfs2_mkdir+0x180/0x430 fs/ocfs2/namei.c:667 vfs_mkdir+0x40c/0x620 fs/namei.c:5410 filename_mkdirat+0x285/0x510 fs/namei.c:5443 __do_sys_mkdirat fs/namei.c:5464 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5461 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}: down_write+0x96/0x200 kernel/locking/rwsem.c:1631 inode_lock include/linux/fs.h:1024 [inline] ocfs2_remove_inode fs/ocfs2/inode.c:767 [inline] ocfs2_wipe_inode fs/ocfs2/inode.c:930 [inline] ocfs2_delete_inode fs/ocfs2/inode.c:1191 [inline] ocfs2_evict_inode+0x1489/0x4390 fs/ocfs2/inode.c:1333 evict+0x624/0xb50 fs/inode.c:822 ocfs2_dentry_iput+0x24d/0x390 fs/ocfs2/dcache.c:407 dentry_kill+0x1b9/0x880 fs/dcache.c:826 finish_dput+0x1a/0x260 fs/dcache.c:1001 ovl_check_rename_whiteout fs/overlayfs/super.c:617 [inline] ovl_make_workdir fs/overlayfs/super.c:713 [inline] ovl_get_workdir+0xba2/0x1980 fs/overlayfs/super.c:836 ovl_fill_super_creds fs/overlayfs/super.c:1449 [inline] ovl_fill_super+0x1702/0x4360 fs/overlayfs/super.c:1561 vfs_get_super fs/super.c:1391 [inline] get_tree_nodev+0xbb/0x150 fs/super.c:1410 vfs_get_tree+0x92/0x2a0 fs/super.c:1933 fc_mount fs/namespace.c:1198 [inline] do_new_mount_fc fs/namespace.c:3772 [inline] do_new_mount+0x319/0xdc0 fs/namespace.c:3848 do_mount fs/namespace.c:4181 [inline] __do_sys_mount fs/namespace.c:4397 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4374 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&ocfs2_sysfile_lock_key[ORPHAN_DIR_SYSTEM_INODE]){+.+.}-{4:4}: down_write+0x96/0x200 kernel/locking/rwsem.c:1631 inode_lock include/linux/fs.h:1024 [inline] ocfs2_wipe_inode fs/ocfs2/inode.c:888 [inline] ocfs2_delete_inode fs/ocfs2/inode.c:1191 [inline] ocfs2_evict_inode+0xe39/0x4390 fs/ocfs2/inode.c:1333 evict+0x624/0xb50 fs/inode.c:822 ocfs2_dentry_iput+0x24d/0x390 fs/ocfs2/dcache.c:407 dentry_kill+0x1b9/0x880 fs/dcache.c:826 finish_dput+0x1a/0x260 fs/dcache.c:1001 ovl_check_rename_whiteout fs/overlayfs/super.c:617 [inline] ovl_make_workdir fs/overlayfs/super.c:713 [inline] ovl_get_workdir+0xba2/0x1980 fs/overlayfs/super.c:836 ovl_fill_super_creds fs/overlayfs/super.c:1449 [inline] ovl_fill_super+0x1702/0x4360 fs/overlayfs/super.c:1561 vfs_get_super fs/super.c:1391 [inline] get_tree_nodev+0xbb/0x150 fs/super.c:1410 vfs_get_tree+0x92/0x2a0 fs/super.c:1933 fc_mount fs/namespace.c:1198 [inline] do_new_mount_fc fs/namespace.c:3772 [inline] do_new_mount+0x319/0xdc0 fs/namespace.c:3848 do_mount fs/namespace.c:4181 [inline] __do_sys_mount fs/namespace.c:4397 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4374 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&osb->nfs_sync_rwlock){.+.+}-{4:4}: check_prev_add kernel/locking/lockdep.c:3209 [inline] check_prevs_add kernel/locking/lockdep.c:3328 [inline] validate_chain kernel/locking/lockdep.c:3952 [inline] __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 down_read+0x4a/0x330 kernel/locking/rwsem.c:1574 ocfs2_nfs_sync_lock+0x106/0x270 fs/ocfs2/dlmglue.c:2875 ocfs2_delete_inode fs/ocfs2/inode.c:1142 [inline] ocfs2_evict_inode+0x3a6/0x4390 fs/ocfs2/inode.c:1333 evict+0x624/0xb50 fs/inode.c:822 ocfs2_dentry_iput+0x24d/0x390 fs/ocfs2/dcache.c:407 dentry_kill+0x1b9/0x880 fs/dcache.c:826 shrink_kill fs/dcache.c:1275 [inline] shrink_dentry_list+0x209/0x310 fs/dcache.c:1292 prune_dcache_sb+0x119/0x180 fs/dcache.c:1374 super_cache_scan+0x35f/0x4a0 fs/super.c:225 do_shrink_slab+0x6d0/0x10e0 mm/shrinker.c:445 shrink_slab_memcg mm/shrinker.c:562 [inline] shrink_slab+0x838/0x1220 mm/shrinker.c:640 shrink_one+0x2a2/0x730 mm/vmscan.c:5119 shrink_many mm/vmscan.c:5180 [inline] lru_gen_shrink_node mm/vmscan.c:5258 [inline] shrink_node+0x35d0/0x3e30 mm/vmscan.c:6247 kswapd_shrink_node mm/vmscan.c:7101 [inline] balance_pgdat mm/vmscan.c:7279 [inline] kswapd+0x185e/0x32c0 mm/vmscan.c:7555 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 other info that might help us debug this: Chain exists of: &osb->nfs_sync_rwlock --> &ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE] --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]); lock(fs_reclaim); rlock(&osb->nfs_sync_rwlock); *** DEADLOCK *** locks held by kswapd0/70: 2, last CPU#0: #0: ffffffff8ee92540 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:7177 [inline] #0: ffffffff8ee92540 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xa08/0x32c0 mm/vmscan.c:7555 #1: ffff888012c380e8 (&type->s_umount_key#55){.+.+}-{4:4}, at: super_trylock_shared fs/super.c:674 [inline] #1: ffff888012c380e8 (&type->s_umount_key#55){.+.+}-{4:4}, at: super_cache_scan+0x94/0x4a0 fs/super.c:200 stack backtrace: CPU: 0 UID: 0 PID: 70 Comm: kswapd0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2087 check_noncircular+0x12f/0x150 kernel/locking/lockdep.c:2219 check_prev_add kernel/locking/lockdep.c:3209 [inline] check_prevs_add kernel/locking/lockdep.c:3328 [inline] validate_chain kernel/locking/lockdep.c:3952 [inline] __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 down_read+0x4a/0x330 kernel/locking/rwsem.c:1574 ocfs2_nfs_sync_lock+0x106/0x270 fs/ocfs2/dlmglue.c:2875 ocfs2_delete_inode fs/ocfs2/inode.c:1142 [inline] ocfs2_evict_inode+0x3a6/0x4390 fs/ocfs2/inode.c:1333 evict+0x624/0xb50 fs/inode.c:822 ocfs2_dentry_iput+0x24d/0x390 fs/ocfs2/dcache.c:407 dentry_kill+0x1b9/0x880 fs/dcache.c:826 shrink_kill fs/dcache.c:1275 [inline] shrink_dentry_list+0x209/0x310 fs/dcache.c:1292 prune_dcache_sb+0x119/0x180 fs/dcache.c:1374 super_cache_scan+0x35f/0x4a0 fs/super.c:225 do_shrink_slab+0x6d0/0x10e0 mm/shrinker.c:445 shrink_slab_memcg mm/shrinker.c:562 [inline] shrink_slab+0x838/0x1220 mm/shrinker.c:640 shrink_one+0x2a2/0x730 mm/vmscan.c:5119 shrink_many mm/vmscan.c:5180 [inline] lru_gen_shrink_node mm/vmscan.c:5258 [inline] shrink_node+0x35d0/0x3e30 mm/vmscan.c:6247 kswapd_shrink_node mm/vmscan.c:7101 [inline] balance_pgdat mm/vmscan.c:7279 [inline] kswapd+0x185e/0x32c0 mm/vmscan.c:7555 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 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