INFO: task syz-executor.3:13323 blocked for more than 143 seconds.
      Not tainted 6.7.0-rc4-syzkaller-gd46efae31672 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:0     pid:13323 tgid:13320 ppid:6156   flags:0x0000000d
Call trace:
 __switch_to+0x314/0x560 arch/arm64/kernel/process.c:556
 context_switch kernel/sched/core.c:5376 [inline]
 __schedule+0x1354/0x2360 kernel/sched/core.c:6688
 __schedule_loop kernel/sched/core.c:6763 [inline]
 schedule+0xb8/0x19c kernel/sched/core.c:6778
 schedule_timeout+0xb8/0x348 kernel/time/timer.c:2143
 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+0x580/0x11c4 kernel/workqueue.c:3195
 nbd_start_device_ioctl drivers/block/nbd.c:1450 [inline]
 __nbd_ioctl drivers/block/nbd.c:1511 [inline]
 nbd_ioctl+0x8cc/0xc38 drivers/block/nbd.c:1551
 blkdev_ioctl+0x3e4/0xae4 block/ioctl.c:633
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl fs/ioctl.c:857 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:857
 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155
 el0_svc+0x54/0x158 arch/arm64/kernel/entry-common.c:678
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffff80008e6c4680 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:300
2 locks held by getty/5857:
 #0: ffff0000d2be40a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff800094e802f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41c/0x1228 drivers/tty/n_tty.c:2201
2 locks held by kworker/u5:3/6139:
 #0: ffff0000ca71ed38 ((wq_completion)nbd3-recv){+.+.}-{0:0}, at: process_one_work+0x560/0x1204 kernel/workqueue.c:2603
 #1: ffff800097457c20 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x5a0/0x1204 kernel/workqueue.c:2605
1 lock held by udevd/13726:
 #0: ffff0000ca3074c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:788
1 lock held by syz-executor.5/14909:
 #0: ffff0000ca3074c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xec/0x740 block/bdev.c:930

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