INFO: task kworker/0:0:5916 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 D26208 5916 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 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: 2 locks held by ksoftirqd/1/18: 3 locks held by kworker/u4:1/23: 1 lock held by khungtaskd/1570: #0: 000000005c08f6ea (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7800: #0: 000000006c29d11d (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 1 lock held by syz-executor.4/8128: 5 locks held by kworker/0:0/5916: #0: 000000002b30b246 ((wq_completion)"usb_hub_wq"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 000000002149c008 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 #2: 00000000d88e788d (&dev->mutex){....}, at: device_lock include/linux/device.h:1174 [inline] #2: 00000000d88e788d (&dev->mutex){....}, at: hub_event+0x11e/0x44a0 drivers/usb/core/hub.c:5387 #3: 00000000686c32e8 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:2983 [inline] #3: 00000000686c32e8 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5069 [inline] #3: 00000000686c32e8 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5253 [inline] #3: 00000000686c32e8 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5361 [inline] #3: 00000000686c32e8 (&port_dev->status_lock){+.+.}, at: hub_event+0x1cb8/0x44a0 drivers/usb/core/hub.c:5441 #4: 0000000099a2c713 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b9/0x3120 drivers/usb/core/hub.c:4578 2 locks held by syz-executor.4/28789: #0: 0000000061d71700 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1826 [inline] #0: 0000000061d71700 (&rq->lock){-.-.}, at: __schedule+0x1f9/0x2040 kernel/sched/core.c:3455 #1: 000000005c08f6ea (rcu_read_lock){....}, at: trace_sched_stat_runtime include/trace/events/sched.h:428 [inline] #1: 000000005c08f6ea (rcu_read_lock){....}, at: update_curr+0x2c3/0x870 kernel/sched/fair.c:857 2 locks held by syz-executor.1/28805: #0: 0000000061d71700 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1826 [inline] #0: 0000000061d71700 (&rq->lock){-.-.}, at: __schedule+0x1f9/0x2040 kernel/sched/core.c:3455 #1: 000000005c08f6ea (rcu_read_lock){....}, at: trace_sched_stat_runtime include/trace/events/sched.h:428 [inline] #1: 000000005c08f6ea (rcu_read_lock){....}, at: update_curr+0x2c3/0x870 kernel/sched/fair.c:857 1 lock held by syz-executor.5/28812: #0: 00000000f8015f3d (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1826 [inline] #0: 00000000f8015f3d (&rq->lock){-.-.}, at: __schedule+0x1f9/0x2040 kernel/sched/core.c:3455 2 locks held by syz-executor.5/28828: 3 locks held by syz-executor.0/28831: 2 locks held by syz-executor.2/28832: #0: 00000000f8015f3d (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1826 [inline] #0: 00000000f8015f3d (&rq->lock){-.-.}, at: __schedule+0x1f9/0x2040 kernel/sched/core.c:3455 #1: 000000005c08f6ea (rcu_read_lock){....}, at: lock_page_memcg+0x0/0x220 include/linux/page_counter.h:64 2 locks held by syz-executor.1/28837: 3 locks held by syz-executor.5/28844: 2 locks held by syz-executor.0/28846: 2 locks held by syz-executor.2/28847: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1570 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8128 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:wait_consider_task+0xb5/0x3910 kernel/exit.c:1336 Code: c8 48 89 4c 24 10 48 c1 e8 03 0f b6 14 28 48 89 c8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 4b 1c 00 00 45 8b a6 6c 04 00 00 10 00 00 00 44 89 e6 e8 1e 1c 2a 00 41 83 fc 10 0f 84 e7 00 00 RSP: 0018:ffff88805af97b00 EFLAGS: 00000246 RAX: 0000000000000007 RBX: 0000000000000000 RCX: ffff88805368e7ec RDX: 0000000000000000 RSI: ffffffff81386a82 RDI: ffff88805af97d00 RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000005 R11: 0000000000000000 R12: 0000000000000000 R13: ffff88805af8e440 R14: ffff88805368e380 R15: ffff88805af8e930 FS: 00005555558e0400(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb2ea0ad000 CR3: 000000005af6a000 CR4: 00000000003426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: do_wait_thread kernel/exit.c:1442 [inline] do_wait+0x429/0x9c0 kernel/exit.c:1513 kernel_wait4+0x14c/0x260 kernel/exit.c:1655 __do_sys_wait4 kernel/exit.c:1667 [inline] __se_sys_wait4+0x149/0x160 kernel/exit.c:1663 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fe1c7cbaf87 Code: 89 7c 24 10 48 89 4c 24 18 e8 35 50 02 00 4c 8b 54 24 18 8b 54 24 14 41 89 c0 48 8b 74 24 08 8b 7c 24 10 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 89 44 24 10 e8 65 50 02 00 8b 44 RSP: 002b:00007fff394ecae0 EFLAGS: 00000293 ORIG_RAX: 000000000000003d RAX: ffffffffffffffda RBX: 00000000000028e8 RCX: 00007fe1c7cbaf87 RDX: 0000000040000001 RSI: 00007fff394ecb6c RDI: 00000000ffffffff RBP: 00007fff394ecb6c R08: 0000000000000000 R09: 00000201a1fbcd27 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032 R13: 00000000001e8e95 R14: 0000000000000000 R15: 00007fff394ecbd0 ---------------- Code disassembly (best guess): 0: c8 48 89 4c enterq $0x8948,$0x4c 4: 24 10 and $0x10,%al 6: 48 c1 e8 03 shr $0x3,%rax a: 0f b6 14 28 movzbl (%rax,%rbp,1),%edx e: 48 89 c8 mov %rcx,%rax 11: 83 e0 07 and $0x7,%eax 14: 83 c0 03 add $0x3,%eax 17: 38 d0 cmp %dl,%al 19: 7c 08 jl 0x23 1b: 84 d2 test %dl,%dl 1d: 0f 85 4b 1c 00 00 jne 0x1c6e 23: 45 8b a6 6c 04 00 00 mov 0x46c(%r14),%r12d * 2a: bf 10 00 00 00 mov $0x10,%edi <-- trapping instruction 2f: 44 89 e6 mov %r12d,%esi 32: e8 1e 1c 2a 00 callq 0x2a1c55 37: 41 83 fc 10 cmp $0x10,%r12d 3b: 0f .byte 0xf 3c: 84 e7 test %ah,%bh