INFO: task kworker/0:3:4717 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/0:3 D25752 4717 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: 0000000042e947d9 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 5 locks held by kworker/0:3/4717: #0: 0000000080d2c7fc ((wq_completion)"usb_hub_wq"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 00000000c3961071 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 #2: 00000000c254f230 (&dev->mutex){....}, at: device_lock include/linux/device.h:1174 [inline] #2: 00000000c254f230 (&dev->mutex){....}, at: hub_event+0x11e/0x44a0 drivers/usb/core/hub.c:5387 #3: 000000000579e8e3 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:2983 [inline] #3: 000000000579e8e3 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5069 [inline] #3: 000000000579e8e3 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5253 [inline] #3: 000000000579e8e3 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5361 [inline] #3: 000000000579e8e3 (&port_dev->status_lock){+.+.}, at: hub_event+0x1cb8/0x44a0 drivers/usb/core/hub.c:5441 #4: 000000006d13e720 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b9/0x3120 drivers/usb/core/hub.c:4578 1 lock held by in:imklog/7844: #0: 000000007cb0f685 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 5 locks held by kworker/1:0/21319: #0: 000000003bcfa3d1 ((wq_completion)"events"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 00000000a5600045 (ser_release_work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 #2: 00000000cd4f3c82 (rtnl_mutex){+.+.}, at: ser_release+0xf9/0x270 drivers/net/caif/caif_serial.c:317 #3: 000000005dc205ea (&caifn->caifdevs.lock){+.+.}, at: caif_device_notify+0x690/0x1210 net/caif/caif_dev.c:454 #4: 000000002d65fe16 (rcu_preempt_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #4: 000000002d65fe16 (rcu_preempt_state.exp_mutex){+.+.}, at: _synchronize_rcu_expedited+0x4dc/0x6f0 kernel/rcu/tree_exp.h:667 2 locks held by kworker/1:2/23369: #0: 000000002e152684 ((wq_completion)"rcu_gp"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 000000004af4db13 ((work_completion)(&rew.rew_work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 3 locks held by syz-executor.4/14818: #0: 00000000e33f36a4 (&tty->legacy_mutex){+.+.}, at: tty_lock+0x6a/0xa0 drivers/tty/tty_mutex.c:19 #1: 000000009124492b (&tty->ldisc_sem){++++}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:320 [inline] #1: 000000009124492b (&tty->ldisc_sem){++++}, at: tty_ldisc_lock+0x4d/0x90 drivers/tty/tty_ldisc.c:344 #2: 00000000cd4f3c82 (rtnl_mutex){+.+.}, at: slip_open+0xe8/0x11d0 drivers/net/slip/slip.c:805 1 lock held by syz-executor.4/14819: #0: 000000009124492b (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 2 locks held by syz-executor.1/14826: ============================================= NMI backtrace for cpu 1 CPU: 1 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4682 Comm: systemd-journal Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_pc+0x22/0x50 kernel/kcov.c:101 Code: 90 90 90 90 90 90 90 90 48 8b 34 24 65 48 8b 04 25 c0 df 01 00 65 8b 15 cc 59 9f 7e 81 e2 00 01 1f 00 75 2b 8b 90 60 13 00 00 <83> fa 02 75 20 48 8b 88 68 13 00 00 8b 80 64 13 00 00 48 8b 11 48 RSP: 0018:ffff8880a1587a28 EFLAGS: 00000246 RAX: ffff8880a157e300 RBX: dffffc0000000000 RCX: ffffffff816c6963 RDX: 0000000000000000 RSI: ffffffff816c68ea RDI: ffffffff886fb508 RBP: ffff8880a1587b00 R08: 0000000000000000 R09: 0000000000000027 R10: 0000000000000006 R11: 0000000000000000 R12: ffffffff886fb460 R13: ffffed10142b0f62 R14: ffffc90001ad40e0 R15: 0000000000000015 FS: 00007f5b0af038c0(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5b07001000 CR3: 00000000a19b3000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ___bpf_prog_run+0x324a/0x4e80 kernel/bpf/core.c:1233 ---------------- Code disassembly (best guess): 0: 90 nop 1: 90 nop 2: 90 nop 3: 90 nop 4: 90 nop 5: 90 nop 6: 90 nop 7: 90 nop 8: 48 8b 34 24 mov (%rsp),%rsi c: 65 48 8b 04 25 c0 df mov %gs:0x1dfc0,%rax 13: 01 00 15: 65 8b 15 cc 59 9f 7e mov %gs:0x7e9f59cc(%rip),%edx # 0x7e9f59e8 1c: 81 e2 00 01 1f 00 and $0x1f0100,%edx 22: 75 2b jne 0x4f 24: 8b 90 60 13 00 00 mov 0x1360(%rax),%edx * 2a: 83 fa 02 cmp $0x2,%edx <-- trapping instruction 2d: 75 20 jne 0x4f 2f: 48 8b 88 68 13 00 00 mov 0x1368(%rax),%rcx 36: 8b 80 64 13 00 00 mov 0x1364(%rax),%eax 3c: 48 8b 11 mov (%rcx),%rdx 3f: 48 rex.W