INFO: task kworker/0:3:8589 blocked for more than 140 seconds. Not tainted 4.14.261-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:3 D26720 8589 2 0x80000000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 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+0xf27/0x28b0 drivers/usb/core/hub.c:4599 hub_port_connect drivers/usb/core/hub.c:4954 [inline] hub_port_connect_change drivers/usb/core/hub.c:5144 [inline] port_event drivers/usb/core/hub.c:5250 [inline] hub_event+0x1948/0x3f60 drivers/usb/core/hub.c:5330 process_one_work+0x793/0x14a0 kernel/workqueue.c:2117 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251 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/0:3/8589: #0: ("usb_hub_wq"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2088 #1: ((&hub->events)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092 #2: (&dev->mutex){....}, at: [] device_lock include/linux/device.h:1082 [inline] #2: (&dev->mutex){....}, at: [] hub_event+0x108/0x3f60 drivers/usb/core/hub.c:5276 #3: (&port_dev->status_lock){+.+.}, at: [] usb_lock_port drivers/usb/core/hub.c:2936 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect drivers/usb/core/hub.c:4920 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect_change drivers/usb/core/hub.c:5144 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] port_event drivers/usb/core/hub.c:5250 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_event+0x15c0/0x3f60 drivers/usb/core/hub.c:5330 #4: (hcd->address0_mutex){+.+.}, at: [] hub_port_connect drivers/usb/core/hub.c:4921 [inline] #4: (hcd->address0_mutex){+.+.}, at: [] hub_port_connect_change drivers/usb/core/hub.c:5144 [inline] #4: (hcd->address0_mutex){+.+.}, at: [] port_event drivers/usb/core/hub.c:5250 [inline] #4: (hcd->address0_mutex){+.+.}, at: [] hub_event+0x15ea/0x3f60 drivers/usb/core/hub.c:5330 2 locks held by kworker/u4:5/9231: #0: ("events_unbound"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2088 #1: ((reaper_work).work){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092 2 locks held by kworker/u4:0/23926: #0: ("events_unbound"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2088 #1: (connector_reaper_work){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092 1 lock held by syz-executor.5/30376: #0: (hashlimit_mutex){+.+.}, at: [] htable_put+0x1a/0x1b0 net/netfilter/xt_hashlimit.c:440 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1533 Comm: khungtaskd Not tainted 4.14.261-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 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: 30532 Comm: kworker/u4:3 Not tainted 4.14.261-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker task: ffff8880781d84c0 task.stack: ffff8880b45f0000 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline] RIP: 0010:lock_acquire+0x1ea/0x3f0 kernel/locking/lockdep.c:4001 RSP: 0018:ffff8880b45f7c10 EFLAGS: 00000082 RAX: 1ffffffff11e1279 RBX: ffff8880781d84c0 RCX: 954a394556f11d11 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000286 RBP: ffffffff88f77980 R08: 0000000000000000 R09: 0000000000020012 R10: ffff8880781d8d98 R11: ffff8880781d84c0 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000002 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa525358010 CR3: 00000000a1774000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:242 [inline] rcu_read_lock include/linux/rcupdate.h:629 [inline] batadv_nc_process_nc_paths.part.0+0xe3/0x350 net/batman-adv/network-coding.c:697 batadv_nc_process_nc_paths net/batman-adv/network-coding.c:689 [inline] batadv_nc_worker+0x8b8/0xc50 net/batman-adv/network-coding.c:737 process_one_work+0x793/0x14a0 kernel/workqueue.c:2117 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Code: c7 83 84 08 00 00 00 00 00 00 48 c1 e8 03 80 3c 10 00 0f 85 ee 01 00 00 48 83 3d 89 c0 ae 07 00 0f 84 4a 01 00 00 48 8b 7c 24 08 <57> 9d 0f 1f 44 00 00 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e 41 5f ---------------- Code disassembly (best guess): 0: c7 83 84 08 00 00 00 movl $0x0,0x884(%rbx) 7: 00 00 00 a: 48 c1 e8 03 shr $0x3,%rax e: 80 3c 10 00 cmpb $0x0,(%rax,%rdx,1) 12: 0f 85 ee 01 00 00 jne 0x206 18: 48 83 3d 89 c0 ae 07 cmpq $0x0,0x7aec089(%rip) # 0x7aec0a9 1f: 00 20: 0f 84 4a 01 00 00 je 0x170 26: 48 8b 7c 24 08 mov 0x8(%rsp),%rdi * 2b: 57 push %rdi <-- trapping instruction 2c: 9d popfq 2d: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 32: 48 83 c4 18 add $0x18,%rsp 36: 5b pop %rbx 37: 5d pop %rbp 38: 41 5c pop %r12 3a: 41 5d pop %r13 3c: 41 5e pop %r14 3e: 41 5f pop %r15