syzbot


possible deadlock in deactivate_super

Status: upstream: reported C repro on 2025/01/29 18:51
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+0ef649bd6963b601e4aa@syzkaller.appspotmail.com
First crash: 57d, last: 8h21m
Bug presence (1)
Date Name Commit Repro Result
2025/03/14 upstream (ToT) 695caca9345a C [report] possible deadlock in deactivate_super
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in deactivate_super (2) ocfs2 C inconclusive 6061 17m 53d 0/28 upstream: reported C repro on 2025/02/02 14:09
upstream possible deadlock in deactivate_super ext4 C unreliable 9 1073d 1093d 0/28 closed as dup on 2022/03/30 22:17
linux-6.1 possible deadlock in deactivate_super origin:upstream C 1041 10h15m 57d 0/3 upstream: reported C repro on 2025/01/29 20:18
Last patch testing requests (1)
Created Duration User Patch Repo Result
2025/03/07 01:24 18m retest repro linux-5.15.y report log

Sample crash report:
(syz-executor999,4165,1):ocfs2_block_check_validate:402 ERROR: CRC32 failed: stored: 0xb3775c19, computed 0x2dd1c265. Applying ECC.
JBD2: Ignoring recovery information on journal
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
5.15.178-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor999/4165 is trying to acquire lock:
ffff88807789d138 ((wq_completion)ocfs2_wq){+.+.}-{0:0}, at: flush_workqueue+0x154/0x1610 kernel/workqueue.c:2830

but task is already holding lock:
ffff88802b1ca0e0 (&type->s_umount_key#50){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&type->s_umount_key#50){++++}-{3:3}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       down_read+0x45/0x2e0 kernel/locking/rwsem.c:1498
       ocfs2_finish_quota_recovery+0x15a/0x2260 fs/ocfs2/quota_local.c:600
       ocfs2_complete_recovery+0x173c/0x24a0 fs/ocfs2/journal.c:1295
       process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
       worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
       kthread+0x3f6/0x4f0 kernel/kthread.c:334
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

-> #1 ((work_completion)(&journal->j_recovery_work)){+.+.}-{0:0}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       process_one_work+0x7f1/0x10c0 kernel/workqueue.c:2286
       worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
       kthread+0x3f6/0x4f0 kernel/kthread.c:334
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

-> #0 ((wq_completion)ocfs2_wq){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
       __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       flush_workqueue+0x170/0x1610 kernel/workqueue.c:2830
       ocfs2_shutdown_local_alloc+0x105/0xa90 fs/ocfs2/localalloc.c:379
       ocfs2_dismount_volume+0x1db/0x8b0 fs/ocfs2/super.c:1882
       generic_shutdown_super+0x130/0x310 fs/super.c:475
       kill_block_super+0x7a/0xe0 fs/super.c:1427
       deactivate_locked_super+0xa0/0x110 fs/super.c:335
       cleanup_mnt+0x44e/0x500 fs/namespace.c:1143
       task_work_run+0x129/0x1a0 kernel/task_work.c:188
       exit_task_work include/linux/task_work.h:33 [inline]
       do_exit+0x6a3/0x2480 kernel/exit.c:874
       do_group_exit+0x144/0x310 kernel/exit.c:996
       __do_sys_exit_group kernel/exit.c:1007 [inline]
       __se_sys_exit_group kernel/exit.c:1005 [inline]
       __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1005
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

other info that might help us debug this:

Chain exists of:
  (wq_completion)ocfs2_wq --> (work_completion)(&journal->j_recovery_work) --> &type->s_umount_key#50

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&type->s_umount_key#50);
                               lock((work_completion)(&journal->j_recovery_work));
                               lock(&type->s_umount_key#50);
  lock((wq_completion)ocfs2_wq);

 *** DEADLOCK ***

1 lock held by syz-executor999/4165:
 #0: ffff88802b1ca0e0 (&type->s_umount_key#50){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365

stack backtrace:
CPU: 1 PID: 4165 Comm: syz-executor999 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 flush_workqueue+0x170/0x1610 kernel/workqueue.c:2830
 ocfs2_shutdown_local_alloc+0x105/0xa90 fs/ocfs2/localalloc.c:379
 ocfs2_dismount_volume+0x1db/0x8b0 fs/ocfs2/super.c:1882
 generic_shutdown_super+0x130/0x310 fs/super.c:475
 kill_block_super+0x7a/0xe0 fs/super.c:1427
 deactivate_locked_super+0xa0/0x110 fs/super.c:335
 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143
 task_work_run+0x129/0x1a0 kernel/task_work.c:188
 exit_task_work include/linux/task_work.h:33 [inline]
 do_exit+0x6a3/0x2480 kernel/exit.c:874
 do_group_exit+0x144/0x310 kernel/exit.c:996
 __do_sys_exit_group kernel/exit.c:1007 [inline]
 __se_sys_exit_group kernel/exit.c:1005 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1005
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f5a3fb5eab9
Code: Unable to access opcode bytes at RIP 0x7f5a3fb5ea8f.
RSP: 002b:00007ffd07f00668 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f5a3fb5eab9
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001
RBP: 00007f5a3fbda2b0 R08: ffffffffffffffb8 R09: 0000000000004701
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5a3fbda2b0
R13: 0000000000000000 R14: 00007f5a3fbdc080 R15: 00007f5a3fb256e0
 </TASK>

Crashes (529):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/02/18 20:12 linux-5.15.y c16c81c81336 c37c7249 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/07 02:41 linux-5.15.y c16c81c81336 8002dd28 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/07 02:22 linux-5.15.y c16c81c81336 8002dd28 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/01/30 11:31 linux-5.15.y 003148680b79 afe4eff5 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/01/29 21:50 linux-5.15.y 003148680b79 136953f1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/03/27 16:31 linux-5.15.y 0c935c049b5c 6c09fb82 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/03/27 16:29 linux-5.15.y 0c935c049b5c 6c09fb82 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/03/26 17:59 linux-5.15.y 0c935c049b5c 20510e88 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/03/26 17:57 linux-5.15.y 0c935c049b5c 20510e88 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/03/26 03:43 linux-5.15.y 0c935c049b5c 89d30d73 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/03/24 01:15 linux-5.15.y 0c935c049b5c 875573af .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/03/23 20:01 linux-5.15.y 0c935c049b5c 4e8d3850 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/03/23 19:59 linux-5.15.y 0c935c049b5c 4e8d3850 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/03/21 01:56 linux-5.15.y 0c935c049b5c 62330552 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/03/17 13:40 linux-5.15.y 0c935c049b5c 948c34e4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/03/13 04:46 linux-5.15.y c16c81c81336 1a5d9317 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/21 01:15 linux-5.15.y c16c81c81336 0808a665 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/19 19:39 linux-5.15.y c16c81c81336 b257a9b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/19 15:25 linux-5.15.y c16c81c81336 b257a9b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/18 22:16 linux-5.15.y c16c81c81336 9a14138f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/18 09:33 linux-5.15.y c16c81c81336 c37c7249 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/18 09:26 linux-5.15.y c16c81c81336 c37c7249 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/17 21:12 linux-5.15.y c16c81c81336 429ea007 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/17 21:12 linux-5.15.y c16c81c81336 429ea007 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/17 09:04 linux-5.15.y c16c81c81336 4121cf9d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/15 06:01 linux-5.15.y c16c81c81336 40a34ec9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/15 06:00 linux-5.15.y c16c81c81336 40a34ec9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/14 13:45 linux-5.15.y c16c81c81336 1022af74 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/14 13:41 linux-5.15.y c16c81c81336 1022af74 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/14 01:40 linux-5.15.y c16c81c81336 d9a046cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/14 01:40 linux-5.15.y c16c81c81336 d9a046cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/13 12:57 linux-5.15.y c16c81c81336 a98a8417 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/13 12:53 linux-5.15.y c16c81c81336 a98a8417 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/02/12 15:44 linux-5.15.y c16c81c81336 b27c2402 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in deactivate_super
2025/03/23 18:54 linux-5.15.y 0c935c049b5c 4e8d3850 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/03/23 08:43 linux-5.15.y 0c935c049b5c 4e8d3850 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/03/23 02:01 linux-5.15.y 0c935c049b5c c6512ef7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/03/22 08:03 linux-5.15.y 0c935c049b5c c6512ef7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/03/22 00:56 linux-5.15.y 0c935c049b5c c6512ef7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/03/21 15:28 linux-5.15.y 0c935c049b5c 62330552 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/03/21 10:41 linux-5.15.y 0c935c049b5c 62330552 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/03/21 10:39 linux-5.15.y 0c935c049b5c 62330552 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/03/18 02:10 linux-5.15.y 0c935c049b5c ce3352cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/03/17 18:57 linux-5.15.y 0c935c049b5c 948c34e4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/03/13 01:30 linux-5.15.y c16c81c81336 1a5d9317 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/02/14 14:50 linux-5.15.y c16c81c81336 1022af74 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/02/13 14:18 linux-5.15.y c16c81c81336 a98a8417 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/02/12 22:49 linux-5.15.y c16c81c81336 b27c2402 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
2025/01/29 18:50 linux-5.15.y 003148680b79 136953f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in deactivate_super
* Struck through repros no longer work on HEAD.