INFO: task kworker/0:9:4194 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:9     state:D stack:    0 pid: 4194 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:
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/0:2/1541:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff8000237f7c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000ce3dc0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000f4101090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/0:3/3625:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff8000220a7c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000f49a40e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000f4709090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
2 locks held by getty/3806:
 #0: ffff0000d4d79098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001bcce2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x2f0/0xf6c drivers/tty/n_tty.c:2158
4 locks held by kworker/1:12/4169:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001fad7c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000d1d400e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000c1b48090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/1:14/4172:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001fb47c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000ec0de0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000ce1c7090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/1:15/4174:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001fb77c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000c1ff00e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000f1394090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/1:16/4175:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001fb87c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000d5caa0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000d6255090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/1:17/4176:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001fb97c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000ecb6c0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000caf92090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/0:9/4194:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001fd27c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000d97e80e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000cbeb3090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/0:11/4196:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001fd47c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000c25f40e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000d053e090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by syz.0.16/4951:
4 locks held by syz.1.17/4976:
4 locks held by syz.2.18/5001:
4 locks held by syz.3.19/5024:
4 locks held by syz.4.20/5063:
4 locks held by syz.5.21/5096:
4 locks held by syz.6.22/5129:
4 locks held by syz.7.23/5161:
4 locks held by syz.8.24/5199:
4 locks held by syz.9.25/5232:

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