INFO: task syz-executor.0:6740 blocked for more than 143 seconds.
      Not tainted 6.13.0-rc3-syzkaller-00020-g573067a5a685 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:0     pid:6740  tgid:6738  ppid:6633   flags:0x0000000d
Call trace:
 __switch_to+0x414/0x788 arch/arm64/kernel/process.c:701 (T)
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1744/0x27f0 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0xbc/0x238 kernel/sched/core.c:6848
 schedule_timeout+0xb4/0x290 kernel/time/sleep_timeout.c:75
 do_wait_for_common+0x30c/0x468 kernel/sched/completion.c:95
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common kernel/sched/completion.c:127 [inline]
 wait_for_completion+0x48/0x60 kernel/sched/completion.c:148
 __flush_workqueue+0x5d0/0x1230 kernel/workqueue.c:3987
 nbd_start_device_ioctl drivers/block/nbd.c:1478 [inline]
 __nbd_ioctl drivers/block/nbd.c:1539 [inline]
 nbd_ioctl+0x8cc/0xc38 drivers/block/nbd.c:1579
 blkdev_ioctl+0x3a8/0xa8c block/ioctl.c:693
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl fs/ioctl.c:892 [inline]
 __arm64_sys_ioctl+0x14c/0x1cc fs/ioctl.c:892
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffff80008fb82560 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:336
2 locks held by kworker/u9:1/5987:
 #0: ffff0000cad0c948 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x60c/0x15cc kernel/workqueue.c:3203
 #1: ffff80009eab7c20 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x6a4/0x15cc kernel/workqueue.c:3203
2 locks held by getty/6179:
 #0: ffff0000d726a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80009ba2b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41c/0x1228 drivers/tty/n_tty.c:2211
3 locks held by syz-executor.0/10962:
 #0: ffff0000cad08998 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x128/0xc38 drivers/block/nbd.c:1572
 #1: ffff0000cac3bb28 (&q->q_usage_counter(io)#33){+.+.}-{0:0}, at: nbd_add_socket+0x174/0x770 drivers/block/nbd.c:1189
 #2: ffff0000cac3bb60 (&q->q_usage_counter(queue)#17){+.+.}-{0:0}, at: nbd_add_socket+0x174/0x770 drivers/block/nbd.c:1189

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