vhci_hcd: release socket
vhci_hcd: disconnect device
vhci_hcd vhci_hcd.0: port 1 already used
vhci_hcd vhci_hcd.0: pdev(2) rhport(0) sockfd(3)
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
INFO: task kworker/0:0:3 blocked for more than 140 seconds.
vhci_hcd: connection closed
vhci_hcd: stop threads
      Not tainted 4.14.202-syzkaller #0
vhci_hcd: release socket
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
vhci_hcd vhci_hcd.0: port 1 already used
kworker/0:0     D26744     3      2 0x80000000
vhci_hcd: disconnect device
Workqueue: usb_hub_wq hub_event
vhci_hcd vhci_hcd.0: pdev(0) rhport(0) sockfd(3)
Call Trace:
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd: connection closed
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
vhci_hcd: stop threads
vhci_hcd: release socket
vhci_hcd: disconnect device
vhci_hcd vhci_hcd.0: port 1 already used
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 usb_kill_urb.part.0+0x125/0x190 drivers/usb/core/urb.c:691
vhci_hcd vhci_hcd.0: pdev(4) rhport(0) sockfd(3)
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd: connection closed
vhci_hcd: stop threads
vhci_hcd: release socket
 usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:686
 usb_start_wait_urb+0x209/0x440 drivers/usb/core/message.c:62
vhci_hcd: disconnect device
vhci_hcd vhci_hcd.0: port 1 already used
 usb_internal_control_msg drivers/usb/core/message.c:100 [inline]
 usb_control_msg+0x302/0x450 drivers/usb/core/message.c:151
 hub_port_init+0xfdc/0x2970 drivers/usb/core/hub.c:4555
vhci_hcd vhci_hcd.0: pdev(1) rhport(0) sockfd(3)
 hub_port_connect drivers/usb/core/hub.c:4905 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5088 [inline]
 port_event drivers/usb/core/hub.c:5194 [inline]
 hub_event+0x1923/0x3dc0 drivers/usb/core/hub.c:5274
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd: connection closed
vhci_hcd: stop threads
vhci_hcd: release socket
vhci_hcd: disconnect device
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
vhci_hcd vhci_hcd.0: port 1 already used
vhci_hcd vhci_hcd.0: port 1 already used
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250
vhci_hcd vhci_hcd.0: pdev(5) rhport(0) sockfd(3)
 kthread+0x30d/0x420 kernel/kthread.c:232
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd vhci_hcd.0: pdev(3) rhport(0) sockfd(3)
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd: connection closed
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
vhci_hcd: connection closed
vhci_hcd: stop threads
INFO: task kworker/1:1:23 blocked for more than 140 seconds.
vhci_hcd: release socket
      Not tainted 4.14.202-syzkaller #0
vhci_hcd: disconnect device
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
vhci_hcd: stop threads
kworker/1:1     D
vhci_hcd: release socket
27232    23      2 0x80000000
vhci_hcd: disconnect device
Workqueue: usb_hub_wq hub_event
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 usb_kill_urb.part.0+0x125/0x190 drivers/usb/core/urb.c:691
 usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:686
 usb_start_wait_urb+0x209/0x440 drivers/usb/core/message.c:62
 usb_internal_control_msg drivers/usb/core/message.c:100 [inline]
 usb_control_msg+0x302/0x450 drivers/usb/core/message.c:151
vhci_hcd vhci_hcd.0: port 1 already used
 hub_port_init+0xfdc/0x2970 drivers/usb/core/hub.c:4555
 hub_port_connect drivers/usb/core/hub.c:4905 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5088 [inline]
 port_event drivers/usb/core/hub.c:5194 [inline]
 hub_event+0x1923/0x3dc0 drivers/usb/core/hub.c:5274
vhci_hcd vhci_hcd.0: pdev(2) rhport(0) sockfd(3)
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd: connection closed
vhci_hcd: stop threads
vhci_hcd: release socket
vhci_hcd: disconnect device
vhci_hcd vhci_hcd.0: port 1 already used
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
vhci_hcd vhci_hcd.0: pdev(0) rhport(0) sockfd(3)
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd: connection closed
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250
vhci_hcd: stop threads
vhci_hcd: release socket
 kthread+0x30d/0x420 kernel/kthread.c:232
vhci_hcd: disconnect device
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
INFO: task kworker/0:2:3449 blocked for more than 140 seconds.
      Not tainted 4.14.202-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
vhci_hcd vhci_hcd.0: port 1 already used
kworker/0:2     D26744  3449      2 0x80000000
Workqueue: usb_hub_wq hub_event
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
vhci_hcd vhci_hcd.0: pdev(4) rhport(0) sockfd(3)
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
vhci_hcd: connection closed
vhci_hcd: stop threads
 usb_kill_urb.part.0+0x125/0x190 drivers/usb/core/urb.c:691
vhci_hcd: release socket
 usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:686
 usb_start_wait_urb+0x209/0x440 drivers/usb/core/message.c:62
vhci_hcd: disconnect device
vhci_hcd vhci_hcd.0: port 1 already used
vhci_hcd vhci_hcd.0: pdev(1) rhport(0) sockfd(3)
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd: connection closed
 usb_internal_control_msg drivers/usb/core/message.c:100 [inline]
 usb_control_msg+0x302/0x450 drivers/usb/core/message.c:151
vhci_hcd: stop threads
vhci_hcd: release socket
 hub_port_init+0xfdc/0x2970 drivers/usb/core/hub.c:4555
vhci_hcd: disconnect device
 hub_port_connect drivers/usb/core/hub.c:4905 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5088 [inline]
 port_event drivers/usb/core/hub.c:5194 [inline]
 hub_event+0x1923/0x3dc0 drivers/usb/core/hub.c:5274
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
vhci_hcd vhci_hcd.0: port 1 already used
vhci_hcd vhci_hcd.0: port 1 already used
vhci_hcd vhci_hcd.0: pdev(3) rhport(0) sockfd(3)
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd: connection closed
vhci_hcd: stop threads
vhci_hcd vhci_hcd.0: pdev(5) rhport(0) sockfd(3)
vhci_hcd: release socket
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd: connection closed
vhci_hcd: disconnect device
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250
vhci_hcd: stop threads
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
INFO: task kworker/0:1:8014 blocked for more than 140 seconds.
vhci_hcd: release socket
      Not tainted 4.14.202-syzkaller #0
vhci_hcd: disconnect device
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/0:1     D26408  8014      2 0x80000000
Workqueue: usb_hub_wq hub_event
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 usb_kill_urb.part.0+0x125/0x190 drivers/usb/core/urb.c:691
 usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:686
 usb_start_wait_urb+0x209/0x440 drivers/usb/core/message.c:62
 usb_internal_control_msg drivers/usb/core/message.c:100 [inline]
 usb_control_msg+0x302/0x450 drivers/usb/core/message.c:151
vhci_hcd vhci_hcd.0: port 1 already used
 hub_port_init+0xfdc/0x2970 drivers/usb/core/hub.c:4555
vhci_hcd vhci_hcd.0: pdev(2) rhport(0) sockfd(3)
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
 hub_port_connect drivers/usb/core/hub.c:4905 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5088 [inline]
 port_event drivers/usb/core/hub.c:5194 [inline]
 hub_event+0x1923/0x3dc0 drivers/usb/core/hub.c:5274
vhci_hcd: connection closed
vhci_hcd: stop threads
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
 process_scheduled_works kernel/workqueue.c:2176 [inline]
 worker_thread+0x7d3/0xff0 kernel/workqueue.c:2252
vhci_hcd: release socket
vhci_hcd vhci_hcd.0: port 1 already used
vhci_hcd: disconnect device
vhci_hcd vhci_hcd.0: pdev(0) rhport(0) sockfd(3)
 kthread+0x30d/0x420 kernel/kthread.c:232
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd: connection closed
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
vhci_hcd: stop threads
INFO: task kworker/1:0:8348 blocked for more than 140 seconds.
vhci_hcd: release socket
      Not tainted 4.14.202-syzkaller #0
vhci_hcd: disconnect device
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
vhci_hcd vhci_hcd.0: port 1 already used
kworker/1:0     D27152  8348      2 0x80000000
Workqueue: usb_hub_wq hub_event
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 usb_kill_urb.part.0+0x125/0x190 drivers/usb/core/urb.c:691
vhci_hcd vhci_hcd.0: pdev(4) rhport(0) sockfd(3)
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd: connection closed
vhci_hcd vhci_hcd.0: port 1 already used
vhci_hcd: stop threads
 usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:686
vhci_hcd: release socket
 usb_start_wait_urb+0x209/0x440 drivers/usb/core/message.c:62
vhci_hcd vhci_hcd.0: pdev(1) rhport(0) sockfd(3)
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd: disconnect device
vhci_hcd: connection closed
vhci_hcd: stop threads
vhci_hcd: release socket
vhci_hcd: disconnect device
 usb_internal_control_msg drivers/usb/core/message.c:100 [inline]
 usb_control_msg+0x302/0x450 drivers/usb/core/message.c:151
 hub_port_init+0xfdc/0x2970 drivers/usb/core/hub.c:4555
 hub_port_connect drivers/usb/core/hub.c:4905 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5088 [inline]
 port_event drivers/usb/core/hub.c:5194 [inline]
 hub_event+0x1923/0x3dc0 drivers/usb/core/hub.c:5274
vhci_hcd vhci_hcd.0: port 1 already used
vhci_hcd vhci_hcd.0: port 1 already used
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
vhci_hcd vhci_hcd.0: pdev(3) rhport(0) sockfd(3)
vhci_hcd vhci_hcd.0: pdev(5) rhport(0) sockfd(3)
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
vhci_hcd: connection closed
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250
 kthread+0x30d/0x420 kernel/kthread.c:232
vhci_hcd: stop threads
vhci_hcd: release socket
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
vhci_hcd: disconnect device
INFO: task kworker/0:3:8741 blocked for more than 140 seconds.
vhci_hcd: connection closed
      Not tainted 4.14.202-syzkaller #0
vhci_hcd: stop threads
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/0:3     D27152  8741      2 0x80000000
Workqueue: usb_hub_wq hub_event
vhci_hcd: release socket
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 usb_kill_urb.part.0+0x125/0x190 drivers/usb/core/urb.c:691
 usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:686
 usb_start_wait_urb+0x209/0x440 drivers/usb/core/message.c:62
 usb_internal_control_msg drivers/usb/core/message.c:100 [inline]
 usb_control_msg+0x302/0x450 drivers/usb/core/message.c:151
 hub_port_init+0xfdc/0x2970 drivers/usb/core/hub.c:4555
 hub_port_connect drivers/usb/core/hub.c:4905 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5088 [inline]
 port_event drivers/usb/core/hub.c:5194 [inline]
 hub_event+0x1923/0x3dc0 drivers/usb/core/hub.c:5274
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

Showing all locks held in the system:
5 locks held by kworker/0:0/3:
 #0:  ("usb_hub_wq"){+.+.}, at: [<ffffffff813733a0>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&hub->events)){+.+.}, at: [<ffffffff813733d6>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
 #2:  (&dev->mutex){....}, at: [<ffffffff84529398>] device_lock include/linux/device.h:1081 [inline]
 #2:  (&dev->mutex){....}, at: [<ffffffff84529398>] hub_event+0x108/0x3dc0 drivers/usb/core/hub.c:5220
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] usb_lock_port drivers/usb/core/hub.c:2934 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_port_connect drivers/usb/core/hub.c:4904 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] port_event drivers/usb/core/hub.c:5194 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_event+0x190e/0x3dc0 drivers/usb/core/hub.c:5274
 #4:  (hcd->address0_mutex){+.+.}, at: [<ffffffff8451eedb>] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429
5 locks held by kworker/1:1/23:
 #0:  ("usb_hub_wq"){+.+.}, at: [<ffffffff813733a0>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&hub->events)){+.+.}, at: [<ffffffff813733d6>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
 #2:  (&dev->mutex){....}, at: [<ffffffff84529398>] device_lock include/linux/device.h:1081 [inline]
 #2:  (&dev->mutex){....}, at: [<ffffffff84529398>] hub_event+0x108/0x3dc0 drivers/usb/core/hub.c:5220
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] usb_lock_port drivers/usb/core/hub.c:2934 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_port_connect drivers/usb/core/hub.c:4904 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] port_event drivers/usb/core/hub.c:5194 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_event+0x190e/0x3dc0 drivers/usb/core/hub.c:5274
 #4:  (hcd->address0_mutex){+.+.}, at: [<ffffffff8451eedb>] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429
1 lock held by khungtaskd/1531:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff81430a04>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
5 locks held by kworker/0:2/3449:
 #0:  ("usb_hub_wq"){+.+.}, at: [<ffffffff813733a0>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&hub->events)){+.+.}, at: [<ffffffff813733d6>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
 #2:  (&dev->mutex){....}, at: [<ffffffff84529398>] device_lock include/linux/device.h:1081 [inline]
 #2:  (&dev->mutex){....}, at: [<ffffffff84529398>] hub_event+0x108/0x3dc0 drivers/usb/core/hub.c:5220
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] usb_lock_port drivers/usb/core/hub.c:2934 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_port_connect drivers/usb/core/hub.c:4904 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] port_event drivers/usb/core/hub.c:5194 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_event+0x190e/0x3dc0 drivers/usb/core/hub.c:5274
 #4:  (hcd->address0_mutex){+.+.}, at: [<ffffffff8451eedb>] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429
5 locks held by kworker/0:1/8014:
 #0:  ("usb_hub_wq"){+.+.}, at: [<ffffffff813733a0>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&hub->events)){+.+.}, at: [<ffffffff813733d6>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
 #2:  (&dev->mutex){....}, at: [<ffffffff84529398>] device_lock include/linux/device.h:1081 [inline]
 #2:  (&dev->mutex){....}, at: [<ffffffff84529398>] hub_event+0x108/0x3dc0 drivers/usb/core/hub.c:5220
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] usb_lock_port drivers/usb/core/hub.c:2934 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_port_connect drivers/usb/core/hub.c:4904 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] port_event drivers/usb/core/hub.c:5194 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_event+0x190e/0x3dc0 drivers/usb/core/hub.c:5274
 #4:  (hcd->address0_mutex){+.+.}, at: [<ffffffff8451eedb>] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429
5 locks held by kworker/1:0/8348:
 #0:  ("usb_hub_wq"){+.+.}, at: [<ffffffff813733a0>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&hub->events)){+.+.}, at: [<ffffffff813733d6>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
 #2:  (&dev->mutex){....}, at: [<ffffffff84529398>] device_lock include/linux/device.h:1081 [inline]
 #2:  (&dev->mutex){....}, at: [<ffffffff84529398>] hub_event+0x108/0x3dc0 drivers/usb/core/hub.c:5220
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] usb_lock_port drivers/usb/core/hub.c:2934 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_port_connect drivers/usb/core/hub.c:4904 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] port_event drivers/usb/core/hub.c:5194 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_event+0x190e/0x3dc0 drivers/usb/core/hub.c:5274
 #4:  (hcd->address0_mutex){+.+.}, at: [<ffffffff8451eedb>] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429
5 locks held by kworker/0:3/8741:
 #0:  ("usb_hub_wq"){+.+.}, at: [<ffffffff813733a0>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&hub->events)){+.+.}, at: [<ffffffff813733d6>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
 #2:  (&dev->mutex){....}, at: [<ffffffff84529398>] device_lock include/linux/device.h:1081 [inline]
 #2:  (&dev->mutex){....}, at: [<ffffffff84529398>] hub_event+0x108/0x3dc0 drivers/usb/core/hub.c:5220
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] usb_lock_port drivers/usb/core/hub.c:2934 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_port_connect drivers/usb/core/hub.c:4904 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] port_event drivers/usb/core/hub.c:5194 [inline]
 #3:  (&port_dev->status_lock){+.+.}, at: [<ffffffff8452ab9e>] hub_event+0x190e/0x3dc0 drivers/usb/core/hub.c:5274
 #4:  (hcd->address0_mutex){+.+.}, at: [<ffffffff8451eedb>] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429

=============================================

vhci_hcd vhci_hcd.0: port 1 already used
vhci_hcd: disconnect device
NMI backtrace for cpu 1
CPU: 1 PID: 1531 Comm: khungtaskd Not tainted 4.14.202-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x283 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x17f lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5b9/0xb40 kernel/hung_task.c:274
 kthread+0x30d/0x420 kernel/kthread.c:232
vhci_hcd vhci_hcd.0: pdev(2) rhport(0) sockfd(3)
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5 Comm: kworker/u4:0 Not tainted 4.14.202-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: phy6 ieee80211_iface_work
task: ffff8880b5ff2140 task.stack: ffff8880b5ff8000
RIP: 0010:compound_head include/linux/page-flags.h:150 [inline]
RIP: 0010:virt_to_head_page include/linux/mm.h:614 [inline]
RIP: 0010:virt_to_cache mm/slab.c:399 [inline]
RIP: 0010:kfree+0x93/0x250 mm/slab.c:3811
RSP: 0018:ffff8880b5fffc38 EFLAGS: 00000086
RAX: ffffea0002541d00 RBX: 0000000000000282 RCX: 000000000000002e
RDX: ffffea0002d2fea0 RSI: 0000000000000000 RDI: ffff888095074580
RBP: ffff888095074580 R08: ffff8880b5ff2140 R09: dffffc0000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff85d9b306
R13: ffff888095074640 R14: ffff888095074670 R15: ffff88809b861a60
FS:  0000000000000000(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4c35fc7fd8 CR3: 000000009a853000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 skb_free_head net/core/skbuff.c:554 [inline]
 skb_release_data+0x5f6/0x820 net/core/skbuff.c:574
 skb_release_all net/core/skbuff.c:631 [inline]
 __kfree_skb net/core/skbuff.c:645 [inline]
 kfree_skb+0xe7/0x390 net/core/skbuff.c:663
 ieee80211_iface_work+0x1d7/0x770 net/mac80211/iface.c:1374
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code: 00 00 e8 81 35 c1 ff 48 89 ef e8 69 f5 a4 ff 48 89 ef 48 ba 00 00 00 00 00 ea ff ff 48 c1 e8 0c 48 c1 e0 06 48 01 d0 48 8b 50 20 <48> 8d 4a ff 83 e2 01 48 0f 45 c1 4c 8b 60 30 49 63 74 24 74 e8