INFO: task kworker/1:2:3687 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/1:2 D25800 3687 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: 1 lock held by khungtaskd/1570: #0: 00000000ab7cba4d (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 5 locks held by kworker/1:2/3687: #0: 000000006a740ae3 ((wq_completion)"usb_hub_wq"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 000000000e9385aa ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 #2: 00000000a3d7cf0d (&dev->mutex){....}, at: device_lock include/linux/device.h:1174 [inline] #2: 00000000a3d7cf0d (&dev->mutex){....}, at: hub_event+0x11e/0x44a0 drivers/usb/core/hub.c:5387 #3: 0000000075675df7 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:2983 [inline] #3: 0000000075675df7 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5069 [inline] #3: 0000000075675df7 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5253 [inline] #3: 0000000075675df7 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5361 [inline] #3: 0000000075675df7 (&port_dev->status_lock){+.+.}, at: hub_event+0x1cb8/0x44a0 drivers/usb/core/hub.c:5441 #4: 000000005fef8ee1 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b9/0x3120 drivers/usb/core/hub.c:4578 1 lock held by in:imklog/7801: #0: 00000000a7cccdc3 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 3 locks held by syz-executor.4/8135: 3 locks held by kworker/u4:6/9445: 2 locks held by kworker/u4:7/9450: #0: 0000000084b65ecc ((wq_completion)"events_unbound"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 0000000089f01f93 ((work_completion)(&sub_info->work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 1 lock held by syz-executor.1/11892: 1 lock held by syz-executor.2/11891: 2 locks held by syz-executor.4/11895: ============================================= 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: 9450 Comm: kworker/u4:7 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:hlock_class kernel/locking/lockdep.c:152 [inline] RIP: 0010:mark_lock+0x66/0x1160 kernel/locking/lockdep.c:3106 Code: c0 74 08 3c 01 0f 8e f1 07 00 00 0f b7 45 20 66 a9 ff 1f 74 7c 48 ba 00 00 00 00 00 fc ff df 4c 89 f1 48 c1 e9 03 0f b6 14 11 <84> d2 74 09 80 fa 03 0f 8e d2 07 00 00 25 ff 1f 00 00 48 69 d8 50 RSP: 0018:ffff88804a057a18 EFLAGS: 00000802 RAX: 000000000000002e RBX: 0000000000000000 RCX: 1ffff1100940914f RDX: 0000000000000000 RSI: ffff88804a048a58 RDI: ffff88804a048180 RBP: ffff88804a048a58 R08: 000000000000002e R09: 0000000000000002 R10: ffff88804a048a58 R11: 0000000000000000 R12: 0000000000000100 R13: ffff88804a048180 R14: ffff88804a048a78 R15: 0000000000000008 FS: 0000000000000000(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055eb97aa6238 CR3: 0000000054402000 CR4: 00000000003426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0x6de/0x3ff0 kernel/locking/lockdep.c:3377 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 rcu_lock_acquire include/linux/rcupdate.h:242 [inline] rcu_read_lock include/linux/rcupdate.h:627 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:419 [inline] batadv_nc_worker+0x12d/0xd50 net/batman-adv/network-coding.c:730 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 ---------------- Code disassembly (best guess): 0: c0 74 08 3c 01 shlb $0x1,0x3c(%rax,%rcx,1) 5: 0f 8e f1 07 00 00 jle 0x7fc b: 0f b7 45 20 movzwl 0x20(%rbp),%eax f: 66 a9 ff 1f test $0x1fff,%ax 13: 74 7c je 0x91 15: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx 1c: fc ff df 1f: 4c 89 f1 mov %r14,%rcx 22: 48 c1 e9 03 shr $0x3,%rcx 26: 0f b6 14 11 movzbl (%rcx,%rdx,1),%edx * 2a: 84 d2 test %dl,%dl <-- trapping instruction 2c: 74 09 je 0x37 2e: 80 fa 03 cmp $0x3,%dl 31: 0f 8e d2 07 00 00 jle 0x809 37: 25 ff 1f 00 00 and $0x1fff,%eax 3c: 48 rex.W 3d: 69 .byte 0x69 3e: d8 .byte 0xd8 3f: 50 push %rax