INFO: task kworker/1:9:4160 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:9     state:D stack:    0 pid: 4160 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/0:0/7:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001b2d7c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000cce460e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000c77ac090 (&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
3 locks held by kworker/u4:4/862:
2 locks held by getty/3803:
 #0: ffff0000d1bec098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001b7b32e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x2f0/0xf6c drivers/tty/n_tty.c:2158
4 locks held by kworker/0:3/4086:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f347c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000ccde20e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000f356a090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/1:9/4160:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f5f7c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000c95ce0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000db1ee090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/1:10/4161:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f607c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000d27a60e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000ce45b090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/1:11/4162:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f617c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000cbdbc0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000cca0e090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/1:12/4163:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f627c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000ce4a60e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000d9207090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/1:16/4167:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f667c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000d58020e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000f3607090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/1:17/4169:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f677c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000c89f40e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000ce495090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
3 locks held by kworker/1:18/4170:
 #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f687c00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000ea325240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x1c8/0x2704 drivers/net/netdevsim/fib.c:1480
4 locks held by kworker/0:6/4255:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f8a7c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000ee11a0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000d5251090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by syz.0.16/5138:
4 locks held by syz.1.17/5161:
4 locks held by syz.2.18/5187:
4 locks held by syz.3.19/5210:
4 locks held by syz.4.20/5248:
4 locks held by syz.5.21/5281:
4 locks held by syz.6.22/5313:
4 locks held by syz.7.23/5345:
4 locks held by syz.8.24/5384:
4 locks held by syz.9.25/5417:

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