vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN INFO: task kworker/0:5:6875 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/0:5 D28056 6875 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+0x18fd/0x3d70 drivers/usb/core/hub.c:5274 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 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Showing all locks held in the system: vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN 1 lock held by khungtaskd/1526: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 5 locks held by kworker/0:5/6875: #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: 1526 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 vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4623 Comm: systemd-journal Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8880a1018100 task.stack: ffff8880a1020000 RIP: 0010:__sanitizer_cov_trace_pc+0x9/0x50 kernel/kcov.c:65 RSP: 0018:ffff8880a1027ef8 EFLAGS: 00000246 RAX: ffff8880a1018100 RBX: ffffffff8134dab0 RCX: 1ffff11014204ff5 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff8880a1027fa8 RBP: ffff8880a1027f58 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffff8880a1018100 R12: ffffffff88f092d8 R13: ffff8880a1027fd0 R14: ffff8880a1018100 R15: 0000000000000000 FS: 00007f64f161f8c0(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2e322000 CR3: 00000000a10a6000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: get_current arch/x86/include/asm/current.h:15 [inline] syscall_return_slowpath arch/x86/entry/common.c:253 [inline] do_syscall_64+0x1fd/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f64f08b7f17 RSP: 002b:00007ffc9d8274c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000027 RAX: 000000000000120f RBX: 000056450b14a1e0 RCX: 00007f64f08b7f17 RDX: 0000000000000000 RSI: 000000004ccd3b94 RDI: 000056450b14a1e0 RBP: 000000000000120f R08: 00007ffc9d9a3000 R09: 0000015a6ca727a8 R10: 000f742e5a6a9619 R11: 0000000000000202 R12: ffffffffffffffff R13: 00007ffc9d827578 R14: 000056450a864958 R15: 0005c23856a332ac Code: 00 e9 9f fe ff ff 4c 89 e7 e8 44 a5 29 00 e9 2c fe ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 80 df 01 00 <48> 85 c0 74 1a 65 8b 15 8b b9 ac 7e 81 e2 00 01 1f 00 75 0b 8b vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN