syzbot


possible deadlock in __ocfs2_flush_truncate_log

Status: upstream: reported C repro on 2025/06/27 02:38
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+579f76264f7c6b368047@syzkaller.appspotmail.com
First crash: 37d, last: 5d21h
Bug presence (1)
Date Name Commit Repro Result
2025/06/29 upstream (ToT) dfba48a70cb6 C [report] possible deadlock in __ocfs2_flush_truncate_log
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in __ocfs2_flush_truncate_log ocfs2 4 C inconclusive 3238 3h24m 140d 2/29 upstream: reported C repro on 2025/03/15 11:28
linux-6.1 possible deadlock in __ocfs2_flush_truncate_log 4 759 12d 141d 0/3 upstream: reported on 2025/03/14 12:11
linux-5.15 possible deadlock in __ocfs2_flush_truncate_log 4 573 11d 141d 0/3 upstream: reported on 2025/03/14 17:58

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
6.6.100-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor/5892 is trying to acquire lock:
ffff88805f0442d8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#4){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
ffff88805f0442d8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#4){+.+.}-{3:3}, at: __ocfs2_flush_truncate_log+0x351/0x10b0 fs/ocfs2/alloc.c:6047

but task is already holding lock:
ffff8880737ca658 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
ffff8880737ca658 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}, at: ocfs2_flush_truncate_log+0x47/0x60 fs/ocfs2/alloc.c:6076

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}:
       down_write+0x97/0x1f0 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:804 [inline]
       ocfs2_move_extent fs/ocfs2/move_extents.c:640 [inline]
       __ocfs2_move_extents_range+0x1a65/0x3360 fs/ocfs2/move_extents.c:860
       ocfs2_move_extents+0x379/0x940 fs/ocfs2/move_extents.c:927
       ocfs2_ioctl_move_extents+0x4e1/0x6c0 fs/ocfs2/move_extents.c:1053
       ocfs2_ioctl+0x195/0x750 fs/ocfs2/ioctl.c:945
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:871 [inline]
       __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#4){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain kernel/locking/lockdep.c:3869 [inline]
       __lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
       lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
       down_write+0x97/0x1f0 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:804 [inline]
       __ocfs2_flush_truncate_log+0x351/0x10b0 fs/ocfs2/alloc.c:6047
       ocfs2_flush_truncate_log+0x4f/0x60 fs/ocfs2/alloc.c:6077
       ocfs2_sync_fs+0x117/0x310 fs/ocfs2/super.c:402
       sync_filesystem+0x1c2/0x220 fs/sync.c:66
       generic_shutdown_super+0x6f/0x2b0 fs/super.c:666
       kill_block_super+0x44/0x90 fs/super.c:1660
       deactivate_locked_super+0x97/0x100 fs/super.c:481
       cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250
       task_work_run+0x1ce/0x250 kernel/task_work.c:239
       resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
       exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
       exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
       __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
       syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
       do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#4);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5);
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#4);

 *** DEADLOCK ***

2 locks held by syz-executor/5892:
 #0: ffff88802c2da0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88802c2da0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88802c2da0e0 (&type->s_umount_key#56){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
 #1: ffff8880737ca658 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
 #1: ffff8880737ca658 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#5){+.+.}-{3:3}, at: ocfs2_flush_truncate_log+0x47/0x60 fs/ocfs2/alloc.c:6076

stack backtrace:
CPU: 1 PID: 5892 Comm: syz-executor Not tainted 6.6.100-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
 check_noncircular+0x2bd/0x3c0 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain kernel/locking/lockdep.c:3869 [inline]
 __lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
 down_write+0x97/0x1f0 kernel/locking/rwsem.c:1573
 inode_lock include/linux/fs.h:804 [inline]
 __ocfs2_flush_truncate_log+0x351/0x10b0 fs/ocfs2/alloc.c:6047
 ocfs2_flush_truncate_log+0x4f/0x60 fs/ocfs2/alloc.c:6077
 ocfs2_sync_fs+0x117/0x310 fs/ocfs2/super.c:402
 sync_filesystem+0x1c2/0x220 fs/sync.c:66
 generic_shutdown_super+0x6f/0x2b0 fs/super.c:666
 kill_block_super+0x44/0x90 fs/super.c:1660
 deactivate_locked_super+0x97/0x100 fs/super.c:481
 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250
 task_work_run+0x1ce/0x250 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f46c538fcd7
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007fffe4813128 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f46c5410b55 RCX: 00007f46c538fcd7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffe48131e0
RBP: 00007fffe48131e0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fffe4814270
R13: 00007f46c5410b55 R14: 00000000000198b6 R15: 00007fffe48142b0
 </TASK>
ocfs2: Unmounting device (7,0) on (node local)

Crashes (118):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/28 11:08 linux-6.6.y dbcb8d8e4163 fb8f743d .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/15 19:10 linux-6.6.y 9247f4e6573a 03fcfc4b .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/15 17:06 linux-6.6.y 9247f4e6573a 03fcfc4b .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/13 11:16 linux-6.6.y 59a2de10b81a 3cda49cf .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/09 04:11 linux-6.6.y a5df3a702b2c 4d9fdfa4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/07 10:19 linux-6.6.y a5df3a702b2c 4f67c4ae .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/28 21:35 linux-6.6.y 3f5b4c104b7d fc9d8ee5 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/28 20:02 linux-6.6.y 3f5b4c104b7d fc9d8ee5 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/28 16:24 linux-6.6.y 3f5b4c104b7d fc9d8ee5 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/19 17:10 linux-6.6.y d96eb99e2f0e 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/18 23:52 linux-6.6.y d96eb99e2f0e 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/18 07:53 linux-6.6.y d96eb99e2f0e 88248e14 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/17 21:05 linux-6.6.y 9247f4e6573a 0d1223f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/17 00:37 linux-6.6.y 9247f4e6573a 44f8051e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/16 14:47 linux-6.6.y 9247f4e6573a 124ec9cc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/16 14:42 linux-6.6.y 9247f4e6573a 124ec9cc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/15 11:35 linux-6.6.y 9247f4e6573a 03fcfc4b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/15 02:13 linux-6.6.y 9247f4e6573a d8fc7335 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/14 15:08 linux-6.6.y 59a2de10b81a d8fc7335 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/13 22:21 linux-6.6.y 59a2de10b81a 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/13 15:21 linux-6.6.y 59a2de10b81a 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/13 15:02 linux-6.6.y 59a2de10b81a 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/11 06:27 linux-6.6.y 59a2de10b81a 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/11 06:26 linux-6.6.y 59a2de10b81a 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/06 12:27 linux-6.6.y a5df3a702b2c 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/05 08:21 linux-6.6.y 3f5b4c104b7d 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/04 20:16 linux-6.6.y 3f5b4c104b7d d869b261 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/04 20:16 linux-6.6.y 3f5b4c104b7d d869b261 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/04 20:16 linux-6.6.y 3f5b4c104b7d d869b261 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/04 01:44 linux-6.6.y 3f5b4c104b7d 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/04 01:43 linux-6.6.y 3f5b4c104b7d 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/04 01:43 linux-6.6.y 3f5b4c104b7d 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/04 01:41 linux-6.6.y 3f5b4c104b7d 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/04 01:41 linux-6.6.y 3f5b4c104b7d 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/04 01:41 linux-6.6.y 3f5b4c104b7d 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/04 01:39 linux-6.6.y 3f5b4c104b7d 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/03 05:40 linux-6.6.y 3f5b4c104b7d 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/03 05:40 linux-6.6.y 3f5b4c104b7d 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/03 05:38 linux-6.6.y 3f5b4c104b7d 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/03 05:38 linux-6.6.y 3f5b4c104b7d 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/03 05:37 linux-6.6.y 3f5b4c104b7d 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/03 05:37 linux-6.6.y 3f5b4c104b7d 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/02 05:37 linux-6.6.y 3f5b4c104b7d bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/02 05:37 linux-6.6.y 3f5b4c104b7d bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/01 15:41 linux-6.6.y 3f5b4c104b7d 091a06cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/01 15:41 linux-6.6.y 3f5b4c104b7d 091a06cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/07/01 15:41 linux-6.6.y 3f5b4c104b7d 091a06cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/30 19:38 linux-6.6.y 3f5b4c104b7d 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/30 19:38 linux-6.6.y 3f5b4c104b7d 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/30 19:38 linux-6.6.y 3f5b4c104b7d 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/30 19:38 linux-6.6.y 3f5b4c104b7d 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/30 19:35 linux-6.6.y 3f5b4c104b7d 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/30 19:35 linux-6.6.y 3f5b4c104b7d 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/30 19:35 linux-6.6.y 3f5b4c104b7d 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/30 19:35 linux-6.6.y 3f5b4c104b7d 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/30 19:35 linux-6.6.y 3f5b4c104b7d 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
2025/06/27 02:38 linux-6.6.y 6282921b6825 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in __ocfs2_flush_truncate_log
* Struck through repros no longer work on HEAD.