INFO: task syz-executor.0:6636 blocked for more than 143 seconds.
      Not tainted 6.8.0-rc7-syzkaller-00135-g707081b61156 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:0     pid:6636  tgid:6635  ppid:6526   flags:0x0000000d
Call trace:
 __switch_to+0x314/0x560 arch/arm64/kernel/process.c:553
 context_switch kernel/sched/core.c:5400 [inline]
 __schedule+0x1498/0x24b4 kernel/sched/core.c:6727
 __schedule_loop kernel/sched/core.c:6802 [inline]
 schedule+0xb8/0x19c kernel/sched/core.c:6817
 schedule_timeout+0xb8/0x348 kernel/time/timer.c:2159
 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:3198
 nbd_start_device_ioctl drivers/block/nbd.c:1443 [inline]
 __nbd_ioctl drivers/block/nbd.c:1504 [inline]
 nbd_ioctl+0x8cc/0xc38 drivers/block/nbd.c:1544
 blkdev_ioctl+0x3e4/0xae4 block/ioctl.c:634
 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:34 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:133
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:152
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffff80008ee74ac0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:297
2 locks held by kworker/u5:1/5743:
 #0: ffff0000ca4d6938 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x560/0x1204 kernel/workqueue.c:2606
 #1: ffff80009f187c20 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x5a0/0x1204 kernel/workqueue.c:2608
2 locks held by getty/5925:
 #0: ffff0000ccbba0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff800093ff02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41c/0x1228 drivers/tty/n_tty.c:2201
1 lock held by syz-executor.0/10442:
 #0: ffff0000ca7ec998 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x128/0xc38 drivers/block/nbd.c:1537

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