INFO: task kworker/u4:0:9 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:0    state:D stack:0     pid:9     ppid:2      flags:0x00000008
Workqueue: writeback wb_workfn (flush-7:0)
Call trace:
 __switch_to+0x2f4/0x550 arch/arm64/kernel/process.c:555
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0xdb4/0x1a6c kernel/sched/core.c:6562
 schedule+0xc4/0x170 kernel/sched/core.c:6638
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6697
 __mutex_lock_common+0xb20/0x1f3c kernel/locking/mutex.c:679
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
 jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
 jfs_write_inode+0x128/0x1f8 fs/jfs/inode.c:138
 write_inode fs/fs-writeback.c:1470 [inline]
 __writeback_single_inode+0x5e0/0x157c fs/fs-writeback.c:1687
 writeback_sb_inodes+0x870/0x1470 fs/fs-writeback.c:1913
 __writeback_inodes_wb+0x104/0x370 fs/fs-writeback.c:1984
 wb_writeback+0x420/0xfdc fs/fs-writeback.c:2089
 wb_check_background_flush fs/fs-writeback.c:2155 [inline]
 wb_do_writeback fs/fs-writeback.c:2243 [inline]
 wb_workfn+0xb40/0xe18 fs/fs-writeback.c:2270
 process_one_work+0x7e4/0x13bc kernel/workqueue.c:2292
 worker_thread+0x8cc/0xfe8 kernel/workqueue.c:2439
 kthread+0x254/0x2e0 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850

Showing all locks held in the system:
4 locks held by kworker/u4:0/9:
 #0: ffff0000c2c2c138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1
 #1: ffff80001cad7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267
 #2: ffff0000d6b040e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:415
 #3: ffff0000e5b5b008 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
4 locks held by kworker/u4:1/11:
 #0: ffff0000c2c2c138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1
 #1: ffff80001caf7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267
 #2: ffff0000e01c20e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:415
 #3: ffff0000e58e01c8 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
1 lock held by rcu_tasks_kthre/12:
 #0: ffff800015507db0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xc48 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffff8000155085d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xc48 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
 #0: ffff800015507440 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:349
4 locks held by kworker/u4:2/39:
 #0: ffff0000c2c2c138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1
 #1: ffff80001cff7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267
 #2: ffff0000c31da0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:415
 #3: ffff0000e5b5f0c8 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
4 locks held by kworker/u4:3/52:
 #0: ffff0000c2c2c138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1
 #1: ffff80001f057c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267
 #2: ffff0000c4b900e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:415
 #3: ffff0000f1463008 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
4 locks held by kworker/u4:4/195:
 #0: ffff0000c2c2c138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1
 #1: ffff800020967c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267
 #2: ffff0000db9ae0e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:415
 #3: ffff0000f146b948 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
3 locks held by kworker/1:2/1517:
 #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1
 #1: ffff800025237c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267
 #2: ffff0000dc386240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x1d8/0x2708 drivers/net/netdevsim/fib.c:1491
4 locks held by kworker/u4:5/1618:
 #0: ffff0000c2c2c138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1
 #1: ffff8000255e7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267
 #2: ffff0000d02440e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:415
 #3: ffff0000f14670c8 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
2 locks held by getty/4081:
 #0: ffff0000d6d92098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80001f9932f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x2e8/0xfa8 drivers/tty/n_tty.c:2198
4 locks held by kworker/u4:6/4456:
 #0: ffff0000c2c2c138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1
 #1: ffff800020dd7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267
 #2: ffff0000f6f460e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:415
 #3: ffff0000f149b948 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
4 locks held by syz.0.17/4555:
4 locks held by syz.1.18/4569:
4 locks held by syz.2.19/4587:
4 locks held by syz.3.20/4605:
4 locks held by kworker/u4:8/4629:
 #0: ffff0000c2c2c138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1
 #1: ffff800021247c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267
 #2: ffff0000f66360e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:415
 #3: ffff0000f1594288 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
4 locks held by syz.4.21/4630:
4 locks held by syz.5.22/4655:
4 locks held by kworker/u4:10/4673:
 #0: ffff0000c2c2c138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1
 #1: ffff8000213d7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267
 #2: ffff0000e02a40e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:415
 #3: ffff0000f15901c8 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
4 locks held by syz.6.23/4688:
4 locks held by syz.7.24/4712:
4 locks held by syz.8.25/4737:
4 locks held by syz.9.26/4763:

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