INFO: task syz-executor.0:7639 blocked for more than 143 seconds.
      Not tainted 6.0.0-rc6-syzkaller-17742-gc194837ebb57 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:    0 pid: 7639 ppid:  3064 flags:0x00000009
Call trace:
 __switch_to+0x180/0x298 arch/arm64/kernel/process.c:557
 context_switch kernel/sched/core.c:5182 [inline]
 __schedule+0x414/0x5a0 kernel/sched/core.c:6494
 schedule+0x64/0xa4 kernel/sched/core.c:6570
 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+0x188/0x25c drivers/block/nbd.c:1418
 __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+0x48/0x164 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654
 el0t_64_sync+0x18c/0x190

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/10:
 #0: ffff80000d433568 (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/11:
 #0: ffff80000d433bb8 (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/26:
 #0: ffff80000d433440 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:279
2 locks held by udevd/2560:
2 locks held by getty/2712:
 #0: ffff0000c7a9d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x28/0x58 drivers/tty/tty_ldisc.c:244
 #1: ffff80000f60e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x19c/0x89c drivers/tty/n_tty.c:2177
2 locks held by kworker/u5:5/3081:
 #0: ffff0000c581f938 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x270/0x504 kernel/workqueue.c:2262
 #1: ffff8000128bbd80 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x29c/0x504 kernel/workqueue.c:2264
3 locks held by kworker/0:10/4294:
 #0: ffff0000c0010738 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x270/0x504 kernel/workqueue.c:2262
 #1: ffff80001fe53d80 ((work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x29c/0x504 kernel/workqueue.c:2264
 #2: ffff80000d349230 (umhelper_sem){++++}-{3:3}, at: usermodehelper_read_lock_wait+0x68/0x154 kernel/umh.c:249
5 locks held by kworker/1:12/8039:
 #0: ffff0000c0dce138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x270/0x504 kernel/workqueue.c:2262
 #1: ffff800021e73d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x29c/0x504 kernel/workqueue.c:2264
 #2: ffff0000c411b990 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline]
 #2: ffff0000c411b990 (&dev->mutex){....}-{3:3}, at: hub_event+0x8c/0x658 drivers/usb/core/hub.c:5681
 #3: ffff000108222190 (&dev->mutex){....}-{3:3}, at: spin_unlock include/linux/spinlock.h:389 [inline]
 #3: ffff000108222190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0xa4/0x418 drivers/usb/gadget/udc/snps_udc_core.c:1650
 #4: ffff000108222918 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline]
 #4: ffff000108222918 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1073 [inline]
 #4: ffff000108222918 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x74/0x3a8 drivers/base/dd.c:1272
3 locks held by kworker/u4:19/11921:
1 lock held by syz-executor.4/14763:
 #0: ffff000104fe0210 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
 #0: ffff000104fe0210 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release net/socket.c:649 [inline]
 #0: ffff000104fe0210 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: sock_close+0x40/0xf0 net/socket.c:1365
2 locks held by udevd/14808:

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