INFO: task syz-executor.0:4425 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:    0 pid: 4425 ppid:  4289 flags:0x0000000d
Call trace:
 __switch_to+0x2f4/0x540 arch/arm64/kernel/process.c:521
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0xdfc/0x1bc4 kernel/sched/core.c:6395
 schedule+0x11c/0x1c8 kernel/sched/core.c:6478
 schedule_timeout+0xc8/0x2f4 kernel/time/timer.c:2093
 do_wait_for_common+0x204/0x374 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+0x4cc/0x104c kernel/workqueue.c:2882
 nbd_start_device_ioctl drivers/block/nbd.c:1380 [inline]
 __nbd_ioctl drivers/block/nbd.c:1442 [inline]
 nbd_ioctl+0x890/0xbf8 drivers/block/nbd.c:1482
 blkdev_ioctl+0x62c/0xc14 block/ioctl.c:604
 block_ioctl+0xa4/0x118 block/fops.c:496
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:181
 el0_svc+0x78/0x1d0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffff800014471360 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:312
2 locks held by getty/3802:
 #0: ffff0000d45d6098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001b9032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x2f0/0xf6c drivers/tty/n_tty.c:2158
2 locks held by kworker/u5:1/4014:
 #0: ffff0000cc1c3138 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x678/0x1138 kernel/workqueue.c:2283
 #1: ffff80001f2d7c00 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1138 kernel/workqueue.c:2285
1 lock held by syz-executor.0/10665:
 #0: ffff0000cc0ff208 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x11c/0xbf8 drivers/block/nbd.c:1475

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