INFO: task kworker/0:7:4672 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:7     state:D stack:    0 pid: 4672 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/0:1/13:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001b337c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000db4e60e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000cdc20090 (&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
2 locks held by kworker/u4:4/446:
4 locks held by kworker/1:2/3341:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff800020dc7c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000cd9400e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000cd9d2090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
2 locks held by getty/3803:
 #0: ffff0000d2da4098 (&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/1:26/4185:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f537c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000dac020e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000f3687090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/1:28/4188:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f6d7c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000cfeda0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000ec629090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/0:6/4671:
 #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: ffff0000c95360e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000caf4d090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/0:7/4672:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f447c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000c12ce0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000cf514090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/0:9/4676:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f207c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000d529a0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000d4b73090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/0:12/4682:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f487c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000cef1e0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000c67c3090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/0:14/4686:
 #0: ffff0000c0021138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283
 #1: ffff80001f4c7c00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285
 #2: ffff0000cc8d60e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x29c fs/reiserfs/super.c:97
 #3: ffff0000d95fe090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by syz.0.16/4967:
4 locks held by syz.1.17/4991:
4 locks held by syz.2.18/5016:
4 locks held by syz.3.19/5038:
4 locks held by syz.4.20/5076:
4 locks held by syz.5.21/5109:
4 locks held by syz.6.22/5142:
4 locks held by syz.7.23/5177:
4 locks held by syz.8.24/5216:
4 locks held by syz.9.25/5248:

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