INFO: task kworker/u4:5:1843 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:5    state:D stack:    0 pid: 1843 ppid:     2 flags:0x00000008
Workqueue: writeback wb_workfn (flush-7:0)
Call trace:
 __switch_to+0x2f4/0x540 arch/arm64/kernel/process.c:521
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0xe20/0x1c6c 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+0xae0/0x1ea4 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0xac/0x11c kernel/locking/mutex.c:743
 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:1505 [inline]
 __writeback_single_inode+0x560/0x11f0 fs/fs-writeback.c:1715
 writeback_sb_inodes+0x868/0x13e4 fs/fs-writeback.c:1940
 __writeback_inodes_wb+0x104/0x370 fs/fs-writeback.c:2011
 wb_writeback+0x408/0xe84 fs/fs-writeback.c:2116
 wb_check_background_flush fs/fs-writeback.c:2182 [inline]
 wb_do_writeback fs/fs-writeback.c:2270 [inline]
 wb_workfn+0xaf8/0xe3c fs/fs-writeback.c:2298
 process_one_work+0x7a4/0x1178 kernel/workqueue.c:2310
 worker_thread+0x8fc/0x103c kernel/workqueue.c:2457
 kthread+0x37c/0x460 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: ffff800014561460 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:312
4 locks held by kworker/u4:5/1843:
 #0: ffff0000c1e37938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x67c/0x1178 kernel/workqueue.c:-1
 #1: ffff800024b57c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6c0/0x1178 kernel/workqueue.c:2285
 #2: ffff0000d725a0e0 (&type->s_umount_key#49){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:418
 #3: ffff0000e315b008 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:108
2 locks held by getty/3803:
 #0: ffff0000d4fa2098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001bf6e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x2ec/0xf90 drivers/tty/n_tty.c:2158
4 locks held by syz-executor.0/4369:

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