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 INFO: task kworker/0:0:3 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. kworker/0:0 D26392 3 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 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 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 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 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 INFO: task kworker/0:1:24 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. kworker/0:1 D27624 24 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: port 1 already used vhci_hcd vhci_hcd.0: port 1 already used vhci_hcd vhci_hcd.0: pdev(4) rhport(0) sockfd(3) vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) 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: connection closed vhci_hcd: stop threads 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: release socket vhci_hcd vhci_hcd.0: pdev(0) rhport(0) sockfd(3) vhci_hcd: disconnect device vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) vhci_hcd vhci_hcd.0: port 1 already used 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(1) rhport(0) sockfd(3) vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 vhci_hcd vhci_hcd.0: port 1 already used vhci_hcd: connection closed vhci_hcd: stop threads worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 vhci_hcd: release socket vhci_hcd: disconnect device 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: connection closed vhci_hcd: connection closed vhci_hcd: stop threads vhci_hcd vhci_hcd.0: port 1 already used vhci_hcd: release socket ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 INFO: task kworker/0:2:3622 blocked for more than 140 seconds. 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: disconnect device Not tainted 4.14.202-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. vhci_hcd: stop threads kworker/0:2 D26656 3622 2 0x80000000 vhci_hcd: release socket Workqueue: usb_hub_wq hub_event vhci_hcd: disconnect device vhci_hcd: connection closed vhci_hcd: stop threads Call Trace: vhci_hcd: release socket context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 vhci_hcd: disconnect device 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 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 vhci_hcd vhci_hcd.0: pdev(2) rhport(0) sockfd(3) vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 vhci_hcd: connection closed 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/1:3:4636 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. kworker/1:3 D27160 4636 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: port 1 already used 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: 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 hub_port_init+0xfdc/0x2970 drivers/usb/core/hub.c:4555 vhci_hcd: release socket 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: disconnect device process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 vhci_hcd vhci_hcd.0: port 1 already used worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 vhci_hcd vhci_hcd.0: pdev(0) rhport(0) sockfd(3) vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 INFO: task kworker/0:3:8046 blocked for more than 140 seconds. vhci_hcd vhci_hcd.0: port 1 already used Not tainted 4.14.202-syzkaller #0 vhci_hcd vhci_hcd.0: port 1 already used "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:3 D26224 8046 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 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 vhci_hcd.0: pdev(5) rhport(0) sockfd(3) vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) usb_kill_urb.part.0+0x125/0x190 drivers/usb/core/urb.c:691 vhci_hcd: connection closed 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 vhci_hcd.0: port 1 already used vhci_hcd: stop threads vhci_hcd: connection closed 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: release socket vhci_hcd: disconnect device vhci_hcd vhci_hcd.0: pdev(3) rhport(0) sockfd(3) hub_port_init+0xfdc/0x2970 drivers/usb/core/hub.c:4555 vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) vhci_hcd: stop threads 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: release socket vhci_hcd: disconnect device process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 vhci_hcd: connection closed vhci_hcd: stop threads vhci_hcd vhci_hcd.0: port 1 already used worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 vhci_hcd: release socket kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 INFO: task kworker/0:4:9200 blocked for more than 140 seconds. vhci_hcd: disconnect device vhci_hcd vhci_hcd.0: pdev(2) rhport(0) sockfd(3) vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) Not tainted 4.14.202-syzkaller #0 vhci_hcd: stop threads "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:4 D26784 9200 2 0x80000000 vhci_hcd: release socket Workqueue: usb_hub_wq hub_event vhci_hcd: disconnect device Call Trace: vhci_hcd: connection closed vhci_hcd: stop threads context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 vhci_hcd: release socket vhci_hcd: disconnect device 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 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 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(4) rhport(0) sockfd(3) process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 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 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: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 #1: ((&hub->events)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 #2: (&dev->mutex){....}, at: [] device_lock include/linux/device.h:1081 [inline] #2: (&dev->mutex){....}, at: [] hub_event+0x108/0x3dc0 drivers/usb/core/hub.c:5220 #3: (&port_dev->status_lock){+.+.}, at: [] usb_lock_port drivers/usb/core/hub.c:2934 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect drivers/usb/core/hub.c:4904 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] port_event drivers/usb/core/hub.c:5194 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_event+0x190e/0x3dc0 drivers/usb/core/hub.c:5274 #4: (hcd->address0_mutex){+.+.}, at: [] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429 5 locks held by kworker/0:1/24: #0: ("usb_hub_wq"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 vhci_hcd vhci_hcd.0: port 1 already used #1: ((&hub->events)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 #2: (&dev->mutex){....}, at: [] device_lock include/linux/device.h:1081 [inline] #2: (&dev->mutex){....}, at: [] hub_event+0x108/0x3dc0 drivers/usb/core/hub.c:5220 #3: (&port_dev->status_lock){+.+.}, at: [] usb_lock_port drivers/usb/core/hub.c:2934 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect drivers/usb/core/hub.c:4904 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] port_event drivers/usb/core/hub.c:5194 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_event+0x190e/0x3dc0 drivers/usb/core/hub.c:5274 #4: (hcd->address0_mutex){+.+.}, at: [] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429 1 lock held by khungtaskd/1531: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 5 locks held by kworker/0:2/3622: #0: ("usb_hub_wq"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 #1: ((&hub->events)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 #2: (&dev->mutex){....}, at: [] device_lock include/linux/device.h:1081 [inline] #2: (&dev->mutex){....}, at: [] hub_event+0x108/0x3dc0 drivers/usb/core/hub.c:5220 #3: (&port_dev->status_lock){+.+.}, at: [] usb_lock_port drivers/usb/core/hub.c:2934 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect drivers/usb/core/hub.c:4904 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] port_event drivers/usb/core/hub.c:5194 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_event+0x190e/0x3dc0 drivers/usb/core/hub.c:5274 #4: (hcd->address0_mutex){+.+.}, at: [] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429 5 locks held by kworker/1:3/4636: #0: ("usb_hub_wq"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 #1: ((&hub->events)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 #2: (&dev->mutex){....}, at: [] device_lock include/linux/device.h:1081 [inline] #2: (&dev->mutex){....}, at: [] hub_event+0x108/0x3dc0 drivers/usb/core/hub.c:5220 #3: (&port_dev->status_lock){+.+.}, at: [] usb_lock_port drivers/usb/core/hub.c:2934 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect drivers/usb/core/hub.c:4904 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] port_event drivers/usb/core/hub.c:5194 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_event+0x190e/0x3dc0 drivers/usb/core/hub.c:5274 #4: (hcd->address0_mutex){+.+.}, at: [] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429 5 locks held by kworker/0:3/8046: #0: ("usb_hub_wq"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 #1: ((&hub->events)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 #2: (&dev->mutex){....}, at: [] device_lock include/linux/device.h:1081 [inline] #2: (&dev->mutex){....}, at: [] hub_event+0x108/0x3dc0 drivers/usb/core/hub.c:5220 #3: (&port_dev->status_lock){+.+.}, at: [] usb_lock_port drivers/usb/core/hub.c:2934 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect drivers/usb/core/hub.c:4904 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] port_event drivers/usb/core/hub.c:5194 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_event+0x190e/0x3dc0 drivers/usb/core/hub.c:5274 #4: (hcd->address0_mutex){+.+.}, at: [] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429 5 locks held by kworker/0:4/9200: #0: ("usb_hub_wq"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 #1: ((&hub->events)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 #2: (&dev->mutex){....}, at: [] device_lock include/linux/device.h:1081 [inline] #2: (&dev->mutex){....}, at: [] hub_event+0x108/0x3dc0 drivers/usb/core/hub.c:5220 #3: (&port_dev->status_lock){+.+.}, at: [] usb_lock_port drivers/usb/core/hub.c:2934 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect drivers/usb/core/hub.c:4904 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] port_event drivers/usb/core/hub.c:5194 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_event+0x190e/0x3dc0 drivers/usb/core/hub.c:5274 #4: (hcd->address0_mutex){+.+.}, at: [] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429 ============================================= vhci_hcd vhci_hcd.0: port 1 already used vhci_hcd vhci_hcd.0: port 1 already used vhci_hcd vhci_hcd.0: pdev(0) 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 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 vhci_hcd: connection closed vhci_hcd: stop threads vhci_hcd vhci_hcd.0: port 1 already used vhci_hcd: release socket vhci_hcd: disconnect device vhci_hcd: stop threads vhci_hcd: connection closed vhci_hcd: release socket vhci_hcd: disconnect device vhci_hcd vhci_hcd.0: pdev(3) rhport(0) sockfd(3) vhci_hcd vhci_hcd.0: devid(0) speed(2) speed_str(full-speed) NMI backtrace for cpu 0 vhci_hcd: stop threads CPU: 0 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 vhci_hcd: release socket nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 vhci_hcd: connection closed 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 vhci_hcd: disconnect device kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: vhci_hcd: stop threads NMI backtrace for cpu 1 CPU: 1 PID: 9290 Comm: kworker/u4:6 Not tainted 4.14.202-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usbip_event event_handler task: ffff8880a1900540 task.stack: ffff8880910e0000 RIP: 0010:__raw_callee_save___pv_queued_spin_unlock+0xc/0x12 RSP: 0018:ffff8880ba507e18 EFLAGS: 00000046 RAX: 0000000000000001 RBX: ffff8880ba524c40 RCX: 1ffff110143201c3 RDX: 0000000000000000 RSI: 0000000000000003 RDI: ffff8880ba524c40 RBP: ffff8880ba524c40 R08: ffffffff8b9ba270 R09: 0000000000000002 R10: 0000000000000000 R11: ffff8880a1900540 R12: ffff8880ba524c48 R13: ffff8880ba524c50 R14: dffffc0000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000768000 CR3: 00000000a3e0b000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:674 [inline] queued_spin_unlock arch/x86/include/asm/qspinlock.h:57 [inline] do_raw_spin_unlock+0x164/0x220 kernel/locking/spinlock_debug.c:135 __raw_spin_unlock include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock+0x1f/0x40 kernel/locking/spinlock.c:184 __run_hrtimer kernel/time/hrtimer.c:1221 [inline] __hrtimer_run_queues+0x2c5/0xc80 kernel/time/hrtimer.c:1287 hrtimer_interrupt+0x1e6/0x5e0 kernel/time/hrtimer.c:1321 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline] smp_apic_timer_interrupt+0x117/0x5e0 arch/x86/kernel/apic/apic.c:1100 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:793 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline] RIP: 0010:console_trylock_spinning kernel/printk/printk.c:1685 [inline] RIP: 0010:vprintk_emit+0x549/0x620 kernel/printk/printk.c:1922 RSP: 0018:ffff8880910e7b78 EFLAGS: 00000297 ORIG_RAX: ffffffffffffff10 RAX: ffff8880a1900540 RBX: 1ffffffff11e1219 RCX: 1ffff110143201c2 RDX: 0000000000000000 RSI: ffff8880a1900df0 RDI: 0000000000000297 RBP: ffff8880910e7bb0 R08: ffffffff8b9afde0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000016 R13: ffff8880b2c98500 R14: 0000000000000297 R15: 0000000000000000 vprintk_func+0x58/0x152 kernel/printk/printk_safe.c:401 printk+0x9e/0xbc kernel/printk/printk.c:1996 vhci_shutdown_connection.cold+0x3c/0x84b drivers/usb/usbip/vhci_hcd.c:1038 event_handler+0x1c3/0x4a0 drivers/usb/usbip/usbip_event.c:92 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: 52 56 57 41 50 41 51 41 52 41 53 e8 ef 10 00 00 41 5b 41 5a 41 59 41 58 5f 5e 5a 59 c3 66 90 52 b8 01 00 00 00 31 d2 f0 0f b0 17 <3c> 01 75 02 5a c3 56 0f b6 f0 e8 c5 ff ff ff 5e 5a c3 66 90 41