INFO: task kworker/0:15:4174 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:15    state:D stack:    0 pid: 4174 ppid:     2 flags:0x00000008
Workqueue: events_long flush_old_commits
Call trace:
 __switch_to+0x2f4/0x558 arch/arm64/kernel/process.c:521
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0xe08/0x1bf8 kernel/sched/core.c:6395
 schedule+0x11c/0x1c8 kernel/sched/core.c:6478
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6537
 __mutex_lock_common+0xa9c/0x1edc kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0xac/0x11c kernel/locking/mutex.c:743
 reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
 reiserfs_sync_fs fs/reiserfs/super.c:76 [inline]
 flush_old_commits+0x194/0x29c fs/reiserfs/super.c:111
 process_one_work+0x79c/0x1140 kernel/workqueue.c:2310
 worker_thread+0x8f4/0x101c kernel/workqueue.c:2457
 kthread+0x374/0x454 kernel/kthread.c:334
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:856

Showing all locks held in the system:
4 locks held by kworker/1:0/21:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001b3c7c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000d23440e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000f492f090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
1 lock held by khungtaskd/27:
 #0: ffff8000143513a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311
4 locks held by kworker/1:2/1541:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff800023597c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000d80cc0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000d698a090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/0:2/1969:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff800024e17c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000dbb160e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000c9e3d090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
2 locks held by getty/3806:
 #0: ffff0000d47a4098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001bd4e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x2f0/0xf6c drivers/tty/n_tty.c:2158
4 locks held by kworker/1:4/4066:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f4f7c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000cb9620e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000ce722090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/1:5/4067:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f4a7c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000d50f80e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000ebf38090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/0:5/4161:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f437c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000dcb720e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000ebf3f090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/0:9/4165:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f477c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000dbf240e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000ea2a5090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/0:15/4174:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f547c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000cc9b00e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000d901d090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
3 locks held by kworker/0:16/4959:
 #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f2d7c00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000d745c240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x1c8/0x2704 drivers/net/netdevsim/fib.c:1480
4 locks held by syz.0.16/5002:
4 locks held by kworker/0:17/5004:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f1a7c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000eb94c0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000eb792090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by syz.1.17/5027:
4 locks held by syz.2.18/5053:
4 locks held by syz.3.19/5075:
4 locks held by syz.4.20/5114:
4 locks held by syz.5.21/5146:
4 locks held by syz.6.22/5178:
4 locks held by syz.7.23/5211:
4 locks held by syz.8.24/5251:
4 locks held by syz.9.25/5284:

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