INFO: task hung in usbdev_open (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: a8ad60f2af58 Linux 4.14.305
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=149dc877480000
kernel config: https://syzkaller.appspot.com/x/.config?x=2f23dc9802022031
dashboard link: https://syzkaller.appspot.com/bug?extid=5741928503aad4795c45
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c38348fd389d/disk-a8ad60f2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3a775d221689/vmlinux-a8ad60f2.xz
kernel image: https://storage.googleapis.com/syzbot-assets/32e71e04d2b4/bzImage-a8ad60f2.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+574192...@syzkaller.appspotmail.com

Bluetooth: hci5 command 0x0406 tx timeout
Bluetooth: hci0 command 0x0406 tx timeout
Bluetooth: hci1 command 0x0406 tx timeout
Bluetooth: hci2 command 0x0406 tx timeout
Bluetooth: hci3 command 0x0406 tx timeout
INFO: task syz-executor.2:9549 blocked for more than 140 seconds.
Not tainted 4.14.305-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2 D29776 9549 8027 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2811 [inline]
__schedule+0x88b/0x1de0 kernel/sched/core.c:3386
schedule+0x8d/0x1b0 kernel/sched/core.c:3430
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3488
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893
device_lock include/linux/device.h:1082 [inline]
usbdev_open+0x142/0x790 drivers/usb/core/devio.c:1023
chrdev_open+0x23c/0x6d0 fs/char_dev.c:423
do_dentry_open+0x44b/0xec0 fs/open.c:777


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