vhci_hcd vhci_hcd.0: devid(0) speed(5) speed_str(super-speed) vhci_hcd: connection closed vhci_hcd: stop threads vhci_hcd: release socket vhci_hcd: disconnect device INFO: task kworker/1:2:3624 blocked for more than 140 seconds. Not tainted 4.14.209-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:2 D28160 3624 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 usb_get_descriptor+0xc0/0x160 drivers/usb/core/message.c:652 usb_get_device_descriptor+0x71/0xd0 drivers/usb/core/message.c:924 hub_port_init+0x629/0x2970 drivers/usb/core/hub.c:4647 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 process_scheduled_works kernel/workqueue.c:2176 [inline] worker_thread+0x7d3/0xff0 kernel/workqueue.c:2252 kthread+0x30d/0x420 kernel/kthread.c:232 vhci_hcd vhci_hcd.0: pdev(0) rhport(0) sockfd(3) ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 vhci_hcd vhci_hcd.0: devid(0) speed(5) speed_str(super-speed) vhci_hcd: connection closed Showing all locks held in the system: vhci_hcd: stop threads 1 lock held by khungtaskd/1531: vhci_hcd: release socket #0: vhci_hcd: disconnect device (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 5 locks held by kworker/1:2/3624: #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 1 lock held by systemd-journal/4610: #0: (&rq->lock){-.-.}, at: [] idle_balance kernel/sched/fair.c:8470 [inline] #0: (&rq->lock){-.-.}, at: [] pick_next_task_fair+0x554/0x1450 kernel/sched/fair.c:6378 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1531 Comm: khungtaskd Not tainted 4.14.209-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 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8100 Comm: kworker/u4:2 Not tainted 4.14.209-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker task: ffff8880afc94640 task.stack: ffff888094870000 RIP: 0010:hlock_class kernel/locking/lockdep.c:148 [inline] RIP: 0010:mark_lock+0x4b/0x1050 kernel/locking/lockdep.c:3168 RSP: 0018:ffff888094877a58 EFLAGS: 00000046 RAX: 0000000000000012 RBX: 0000000000000000 RCX: 0000000000000008 RDX: 1ffff11015f929e7 RSI: ffff8880afc94f18 RDI: ffff8880afc94640 RBP: ffff8880afc94f18 R08: 0000000000000000 R09: 0000000000020012 R10: ffff8880afc94f18 R11: ffff8880afc94640 R12: 0000000000000100 R13: ffff8880afc94640 R14: ffff8880afc94f38 R15: 0000000000000008 FS: 0000000000000000(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fea7f7e2000 CR3: 000000009bfb0000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0x5fc/0x3f20 kernel/locking/lockdep.c:3452 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 rcu_lock_acquire include/linux/rcupdate.h:242 [inline] rcu_read_lock include/linux/rcupdate.h:629 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:416 [inline] batadv_nc_worker+0x124/0xc50 net/batman-adv/network-coding.c:726 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: 54 48 c1 ea 03 41 bc 01 00 00 00 55 41 d3 e4 48 89 f5 53 48 83 ec 18 0f b6 04 02 84 c0 74 08 3c 01 0f 8e d6 07 00 00 0f b7 45 20 <66> a9 ff 1f 74 7c 48 ba 00 00 00 00 00 fc ff df 4c 89 f1 48 c1