INFO: task kworker/u8:1:13 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:1    state:D stack:0     pid:13    tgid:13    ppid:2      task_flags:0x4208060 flags:0x00000010
Workqueue: writeback wb_workfn (flush-7:0)
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1250/0x2a7c kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:6960
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7017
 __mutex_lock_common+0xd04/0x2678 kernel/locking/mutex.c:692
 __mutex_lock kernel/locking/mutex.c:776 [inline]
 mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:828
 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:1582 [inline]
 __writeback_single_inode+0x6b0/0x16b8 fs/fs-writeback.c:1802
 writeback_sb_inodes+0x73c/0x16b4 fs/fs-writeback.c:2030
 __writeback_inodes_wb+0xec/0x228 fs/fs-writeback.c:2107
 wb_writeback+0x3c8/0xd70 fs/fs-writeback.c:2218
 wb_check_old_data_flush fs/fs-writeback.c:2322 [inline]
 wb_do_writeback fs/fs-writeback.c:2375 [inline]
 wb_workfn+0xa08/0xdc0 fs/fs-writeback.c:2403
 process_one_work+0x7c0/0x1558 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x958/0xed8 kernel/workqueue.c:3421
 kthread+0x5fc/0x75c kernel/kthread.c:463
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844

Showing all locks held in the system:
4 locks held by kworker/u8:1/13:
 #0: ffff0000c1ff3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff800097d07be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff0000cae840e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563
 #3: ffff0000f7501418 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
1 lock held by khungtaskd/32:
 #0: ffff80008fa5b520 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
4 locks held by kworker/u8:3/42:
 #0: ffff0000c1ff3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff800097ff7be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff0000c327c0e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563
 #3: ffff0000f7505430 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
2 locks held by pr/ttyAMA-1/43:
4 locks held by kworker/u8:8/1571:
 #0: ffff0000c1ff3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff8000a0557be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff0000d3d8c0e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563
 #3: ffff0000e6551d40 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
4 locks held by kworker/u8:11/1977:
 #0: ffff0000c1ff3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff8000a1527be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff0000dade40e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563
 #3: ffff0000f7451418 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
4 locks held by kworker/u8:16/3257:
 #0: ffff0000c1ff3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff8000a1df7be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff0000f51000e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563
 #3: ffff0000f7795430 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
4 locks held by kworker/u8:21/5275:
 #0: ffff0000c1ff3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff80009eb17be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff0000d30dc0e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563
 #3: ffff0000f7434b08 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
4 locks held by kworker/u8:23/5485:
 #0: ffff0000c1ff3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff8000a38a7be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff0000c6bc60e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563
 #3: ffff0000f7455430 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
1 lock held by klogd/6203:
2 locks held by getty/6357:
 #0: ffff0000d60df0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff800099f2b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfc8 drivers/tty/n_tty.c:2211
4 locks held by syz.0.17/6787:
4 locks held by syz.1.18/6815:
4 locks held by syz.2.19/6838:
4 locks held by syz.3.20/6862:
4 locks held by syz.4.21/6896:
4 locks held by syz.5.22/6934:
4 locks held by syz.6.23/6965:
4 locks held by syz.7.24/6999:
4 locks held by kworker/u8:27/7001:
 #0: ffff0000c1ff3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff80009f097be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff0000cc2e20e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563
 #3: ffff0000f7791d40 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
4 locks held by syz.8.25/7042:
4 locks held by kworker/u8:34/7046:
 #0: ffff0000c1ff3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff80009f087be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff0000d658a0e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563
 #3: ffff0000fe4e1d40 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
4 locks held by syz.9.26/7081:
3 locks held by syz.0.33/7115:

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