INFO: task kworker/0:0:5 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:0 D25712 5 2 0x80000000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 usb_kill_urb.part.0+0x197/0x220 drivers/usb/core/urb.c:697 usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:692 usb_start_wait_urb+0x252/0x4c0 drivers/usb/core/message.c:63 usb_internal_control_msg drivers/usb/core/message.c:101 [inline] usb_control_msg+0x31c/0x4a0 drivers/usb/core/message.c:152 usb_get_descriptor+0xc5/0x1b0 drivers/usb/core/message.c:654 usb_get_device_descriptor+0x81/0xf0 drivers/usb/core/message.c:926 hub_port_init+0x74b/0x3120 drivers/usb/core/hub.c:4799 hub_port_connect drivers/usb/core/hub.c:5070 [inline] hub_port_connect_change drivers/usb/core/hub.c:5253 [inline] port_event drivers/usb/core/hub.c:5361 [inline] hub_event+0x1ccd/0x44a0 drivers/usb/core/hub.c:5441 caif:caif_disconnect_client(): nothing to disconnect process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Showing all locks held in the system: 5 locks held by kworker/0:0/5: #0: 000000003c8dfbc5 ((wq_completion)"usb_hub_wq"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 000000003cf1e6de ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 #2: 00000000e1ffbc29 (&dev->mutex){....}, at: device_lock include/linux/device.h:1174 [inline] #2: 00000000e1ffbc29 (&dev->mutex){....}, at: hub_event+0x11e/0x44a0 drivers/usb/core/hub.c:5387 #3: 00000000de2a45be (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:2983 [inline] #3: 00000000de2a45be (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5069 [inline] #3: 00000000de2a45be (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5253 [inline] #3: 00000000de2a45be (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5361 [inline] #3: 00000000de2a45be (&port_dev->status_lock){+.+.}, at: hub_event+0x1cb8/0x44a0 drivers/usb/core/hub.c:5441 #4: 00000000e221f299 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b9/0x3120 drivers/usb/core/hub.c:4578 3 locks held by kworker/u4:2/50: 1 lock held by khungtaskd/1571: #0: 00000000e25db2a5 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by systemd-udevd/4700: 1 lock held by in:imklog/7866: #0: 000000008c3c91d6 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 3 locks held by rs:main Q:Reg/7867: 2 locks held by systemd-udevd/10984: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1571 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:strlen+0x5c/0x90 lib/string.c:539 Code: 48 bb 00 00 00 00 00 fc ff df 48 89 e8 48 83 c0 01 48 89 c2 48 89 c1 48 c1 ea 03 83 e1 07 0f b6 14 1a 38 ca 7f 04 84 d2 75 1f <80> 38 00 75 de 48 83 c4 08 48 29 e8 5b 5d c3 48 83 c4 08 31 c0 5b RSP: 0018:ffff8880ba0079e8 EFLAGS: 00000046 RAX: ffffffff88b3f1c3 RBX: dffffc0000000000 RCX: 0000000000000003 RDX: 0000000000000000 RSI: ffffffff8a462a78 RDI: ffffffff88b3f1c0 RBP: ffffffff88b3f1c0 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000005 R11: 0000000000000000 R12: ffffffff89f6d420 R13: ffffffff8a462a78 R14: 0000000000000000 R15: ffff8880ba007ac8 FS: 0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f47e4004000 CR3: 000000002cd39000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: strlen include/linux/string.h:299 [inline] trace_event_get_offsets_lock_acquire include/trace/events/lock.h:13 [inline] perf_trace_lock_acquire+0xbe/0x530 include/trace/events/lock.h:13 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0x298/0x3c0 kernel/locking/lockdep.c:3907 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:152 __free_object+0x17/0x1e0 lib/debugobjects.c:251 free_object lib/debugobjects.c:272 [inline] debug_object_free lib/debugobjects.c:652 [inline] debug_object_free+0x1cc/0x380 lib/debugobjects.c:624 scsi_end_request+0x1f8/0xb60 drivers/scsi/scsi_lib.c:687 scsi_io_completion+0x279/0x17c0 drivers/scsi/scsi_lib.c:1103 scsi_softirq_done+0x336/0x3d0 drivers/scsi/scsi_lib.c:1759 __blk_mq_complete_request block/blk-mq.c:583 [inline] blk_mq_complete_request+0x472/0x660 block/blk-mq.c:620 virtscsi_vq_done drivers/scsi/virtio_scsi.c:223 [inline] virtscsi_req_done+0x14b/0x210 drivers/scsi/virtio_scsi.c:238 vring_interrupt+0x12f/0x220 drivers/virtio/virtio_ring.c:953 __handle_irq_event_percpu+0x27e/0x8e0 kernel/irq/handle.c:149 handle_irq_event_percpu kernel/irq/handle.c:189 [inline] handle_irq_event+0x102/0x290 kernel/irq/handle.c:206 handle_edge_irq+0x260/0xcf0 kernel/irq/chip.c:800 generic_handle_irq_desc include/linux/irqdesc.h:155 [inline] handle_irq+0x35/0x50 arch/x86/kernel/irq_64.c:87 do_IRQ+0x93/0x1c0 arch/x86/kernel/irq.c:246 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:670 RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61 Code: 48 89 df e8 f4 20 7f f9 e9 2e ff ff ff 48 89 df e8 e7 20 7f f9 eb 82 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 14 43 4e 00 fb f4 90 e9 07 00 00 00 0f 00 2d 04 43 4e 00 f4 c3 90 90 41 56 41 55 RSP: 0018:ffffffff89e07d40 EFLAGS: 00000282 ORIG_RAX: ffffffffffffffdb RAX: 1ffffffff13e3054 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffffffff89e78904 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff89f18290 R13: 1ffffffff13c0fb2 R14: 0000000000000000 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline] default_idle+0x49/0x310 arch/x86/kernel/process.c:557 cpuidle_idle_call kernel/sched/idle.c:153 [inline] do_idle+0x2ec/0x4b0 kernel/sched/idle.c:263 cpu_startup_entry+0xc5/0xe0 kernel/sched/idle.c:369 start_kernel+0x8d6/0x911 init/main.c:736 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 ---------------- Code disassembly (best guess): 0: 48 bb 00 00 00 00 00 movabs $0xdffffc0000000000,%rbx 7: fc ff df a: 48 89 e8 mov %rbp,%rax d: 48 83 c0 01 add $0x1,%rax 11: 48 89 c2 mov %rax,%rdx 14: 48 89 c1 mov %rax,%rcx 17: 48 c1 ea 03 shr $0x3,%rdx 1b: 83 e1 07 and $0x7,%ecx 1e: 0f b6 14 1a movzbl (%rdx,%rbx,1),%edx 22: 38 ca cmp %cl,%dl 24: 7f 04 jg 0x2a 26: 84 d2 test %dl,%dl 28: 75 1f jne 0x49 * 2a: 80 38 00 cmpb $0x0,(%rax) <-- trapping instruction 2d: 75 de jne 0xd 2f: 48 83 c4 08 add $0x8,%rsp 33: 48 29 e8 sub %rbp,%rax 36: 5b pop %rbx 37: 5d pop %rbp 38: c3 retq 39: 48 83 c4 08 add $0x8,%rsp 3d: 31 c0 xor %eax,%eax 3f: 5b pop %rbx