vhci_hcd vhci_hcd.0: Device attached vhci_hcd: connection closed vhci_hcd: stop threads vhci_hcd: release socket vhci_hcd: disconnect device INFO: task kworker/0:0:10567 blocked for more than 140 seconds. Not tainted 4.14.232-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:0 D28424 10567 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 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429 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+0x18fd/0x3d70 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: 1 lock held by khungtaskd/1533: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 5 locks held by kworker/0:0/10567: #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+0x108/0x3d70 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+0x18e8/0x3d70 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/1:4/18093: #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+0x108/0x3d70 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+0x18e8/0x3d70 drivers/usb/core/hub.c:5274 #4: (hcd->address0_mutex){+.+.}, at: [] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1533 Comm: khungtaskd Not tainted 4.14.232-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+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 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 vhci_hcd.0: pdev(3) rhport(0) sockfd(5) kthread+0x30d/0x420 kernel/kthread.c:232 vhci_hcd vhci_hcd.0: devid(0) speed(5) speed_str(super-speed) ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7965 Comm: syz-fuzzer Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff888097dbe2c0 task.stack: ffff888096480000 RIP: 0010:__read_once_size include/linux/compiler.h:183 [inline] RIP: 0010:get_running_cputimer include/linux/sched/cputime.h:84 [inline] RIP: 0010:account_group_exec_runtime include/linux/sched/cputime.h:169 [inline] RIP: 0010:update_curr+0x31c/0x670 kernel/sched/fair.c:857 RSP: 0018:ffff888096487b00 EFLAGS: 00000806 RAX: 0000000000000000 RBX: ffff888097dbe340 RCX: 1ffff11012fb7d6e RDX: 1ffff110168fe0e7 RSI: 0000000000000002 RDI: ffff8880b47f0738 RBP: ffff8880ba42a3a0 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: ffff888097dbe2c0 R12: 0000000000004d94 R13: ffff8880b47f0600 R14: ffff8880b47f0720 R15: ffff888097dbe2c0 FS: 000000c00002e090(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000003433708 CR3: 00000000abccd000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: dequeue_entity+0x24/0x2150 kernel/sched/fair.c:3805 dequeue_task_fair+0x5c/0x12a0 kernel/sched/fair.c:4959 __schedule+0x2b1/0x1de0 kernel/sched/core.c:3333 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 freezable_schedule include/linux/freezer.h:172 [inline] do_nanosleep+0x229/0x600 kernel/time/hrtimer.c:1483 hrtimer_nanosleep+0x1da/0x4b0 kernel/time/hrtimer.c:1537 SYSC_nanosleep kernel/time/hrtimer.c:1569 [inline] SyS_nanosleep+0x116/0x170 kernel/time/hrtimer.c:1556 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x46dabd RSP: 002b:000000c00003df18 EFLAGS: 00000202 ORIG_RAX: 0000000000000023 RAX: ffffffffffffffda RBX: 0000000000004e20 RCX: 000000000046dabd RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000c00003df18 RBP: 000000c00003df28 R08: 00007ffedf5f7000 R09: 0000013436064141 R10: 00068c724bf8ec42 R11: 0000000000000202 R12: 000000000043b6a0 R13: 0000000000000000 R14: 0000000000947a7c R15: 0000000000000000 Code: 00 4c 8b ab 80 06 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d bd 38 01 00 00 4d 8d b5 20 01 00 00 48 89 fa 48 c1 ea 03 0f b6 04 02 <48> 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 ef 02 00 00 41 0f b6