INFO: task syz-executor.5:19057 blocked for more than 143 seconds.
      Not tainted 6.1.0-rc8-syzkaller-33330-ga5541c0811a0 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5  state:D stack:0     pid:19057 ppid:3136   flags:0x00000009
Call trace:
 __switch_to+0x180/0x298 arch/arm64/kernel/process.c:555
 context_switch kernel/sched/core.c:5209 [inline]
 __schedule+0x408/0x594 kernel/sched/core.c:6521
 schedule+0x64/0xa4 kernel/sched/core.c:6597
 schedule_timeout+0x64/0x1b4 kernel/time/timer.c:1911
 do_wait_for_common+0xf4/0x184 kernel/sched/completion.c:85
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x48/0x60 kernel/sched/completion.c:138
 __flush_workqueue+0x2b0/0x6dc kernel/workqueue.c:2861
 nbd_start_device_ioctl+0x1e4/0x2b8 drivers/block/nbd.c:1419
 __nbd_ioctl+0x16c/0x334 drivers/block/nbd.c:1481
 nbd_ioctl+0xec/0x13c drivers/block/nbd.c:1521
 blkdev_ioctl+0x24c/0x6d8 block/ioctl.c:614
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0xd0/0x140 fs/ioctl.c:856
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
 el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x48/0x140 arch/arm64/kernel/syscall.c:197
 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/11:
 #0: ffff80000d4a4768 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x3c/0x450 kernel/rcu/tasks.h:507
1 lock held by rcu_tasks_trace/12:
 #0: ffff80000d4a4db8 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x3c/0x450 kernel/rcu/tasks.h:507
1 lock held by khungtaskd/27:
 #0: ffff80000d4a4640 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:303
2 locks held by kworker/u4:3/980:
 #0: ffff0000c0014938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x270/0x504 kernel/workqueue.c:2262
 #1: ffff80001424bd80 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x29c/0x504 kernel/workqueue.c:2264
2 locks held by kworker/u4:4/1007:
1 lock held by udevd/2603:
 #0: ffff0001fefcfe98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:537 [inline]
 #0: ffff0001fefcfe98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1354 [inline]
 #0: ffff0001fefcfe98 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1644 [inline]
 #0: ffff0001fefcfe98 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0xa4/0x594 kernel/sched/core.c:6438
2 locks held by getty/2765:
 #0: ffff0000c9810098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x28/0x58 drivers/tty/tty_ldisc.c:244
 #1: ffff80000f6be2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x19c/0x89c drivers/tty/n_tty.c:2177
2 locks held by kworker/u5:6/3145:
 #0: ffff0000c614bd38 ((wq_completion)nbd5-recv){+.+.}-{0:0}, at: process_one_work+0x270/0x504 kernel/workqueue.c:2262
 #1: ffff800012dd3d80 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x29c/0x504 kernel/workqueue.c:2264
2 locks held by kworker/u4:12/9100:
 #0: ffff0000c0014938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x270/0x504 kernel/workqueue.c:2262
 #1: ffff800021a1bd80 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x29c/0x504 kernel/workqueue.c:2264
1 lock held by udevd/19156:
 #0: ffff0001fefeee98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:537 [inline]
 #0: ffff0001fefeee98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1354 [inline]
 #0: ffff0001fefeee98 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1644 [inline]
 #0: ffff0001fefeee98 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0xa4/0x594 kernel/sched/core.c:6438
2 locks held by kworker/u4:21/23081:
1 lock held by syz-executor.1/23178:
 #0: ffff00011575e3d0 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
 #0: ffff00011575e3d0 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release net/socket.c:649 [inline]
 #0: ffff00011575e3d0 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: sock_close+0x40/0xf0 net/socket.c:1365

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