INFO: task syz.0.313:5966 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.313       state:D stack:0     pid:5966  tgid:5966  ppid:4714   task_flags:0x400040 flags:0x00800001
Call trace:
 __switch_to+0x2b0/0x6e0 arch/arm64/kernel/process.c:775 (T)
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x1370/0x2d80 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x13c/0x20c kernel/sched/core.c:7326
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x4ec/0xf14 kernel/locking/mutex.c:821
 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:874
 bdev_release+0x128/0x328 block/bdev.c:1131
 blkdev_release+0x20/0x34 block/fops.c:680
 __fput+0x338/0x74c fs/file_table.c:512
 ____fput+0x20/0x30 fs/file_table.c:540
 task_work_run+0x1cc/0x25c kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x10c/0x17c kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 arm64_syscall_exit_to_user_mode arch/arm64/kernel/entry-common.c:88 [inline]
 el0_svc+0x18c/0x260 arch/arm64/kernel/entry-common.c:737
 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594

Showing all locks held in the system:
4 locks held by kworker/1:0/24:
1 lock held by khungtaskd/31:
 #0: ffff800088cf6fe0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffff800088cf6fe0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffff800088cf6fe0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x4c/0x188 kernel/locking/lockdep.c:6775
2 locks held by getty/4493:
 #0: ffff0000cf7b30a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff8000924cb2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x348/0xf78 drivers/tty/n_tty.c:2211
2 locks held by kworker/u9:3/4718:
 #0: ffff0000c6c15940 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #0: ffff0000c6c15940 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_scheduled_works+0x734/0x10b8 kernel/workqueue.c:3405
 #1: ffff800093477c40 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
 #1: ffff800093477c40 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_scheduled_works+0x73c/0x10b8 kernel/workqueue.c:3405
1 lock held by udevd/5075:
 #0: ffff0000c5973350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xc4/0x880 block/bdev.c:948
1 lock held by syz.0.313/5966:
 #0: ffff0000c5973350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x128/0x328 block/bdev.c:1131

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