INFO: task kworker/0:1:12 blocked for more than 143 seconds. Not tainted 5.6.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:1 D24256 12 2 0x80004000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0xcd/0x2b0 kernel/sched/core.c:4154 schedule_timeout+0x682/0xb20 kernel/time/timer.c:1871 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x26f/0x3c0 kernel/sched/completion.c:136 kthread_stop+0x17a/0x780 kernel/kthread.c:559 hwrng_unregister+0x24f/0x330 drivers/char/hw_random/core.c:556 chaoskey_disconnect+0x216/0x290 drivers/usb/misc/chaoskey.c:232 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:436 __device_release_driver drivers/base/dd.c:1137 [inline] device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1168 bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:533 device_del+0x481/0xd30 drivers/base/core.c:2677 usb_disable_device+0x23d/0x790 drivers/usb/core/message.c:1237 usb_disconnect+0x293/0x900 drivers/usb/core/hub.c:2211 hub_port_connect drivers/usb/core/hub.c:5046 [inline] hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] port_event drivers/usb/core/hub.c:5481 [inline] hub_event+0x1a1d/0x4300 drivers/usb/core/hub.c:5563 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264 worker_thread+0x96/0xe20 kernel/workqueue.c:2410 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Showing all locks held in the system: 5 locks held by kworker/0:0/5: #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881da1dfdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d4960200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4960200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881d4962540 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:3008 [inline] #3: ffff8881d4962540 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5126 [inline] #3: ffff8881d4962540 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] #3: ffff8881d4962540 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5481 [inline] #3: ffff8881d4962540 (&port_dev->status_lock){+.+.}, at: hub_event+0x1fae/0x4300 drivers/usb/core/hub.c:5563 #4: ffff8881d4e8a660 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b6/0x2e60 drivers/usb/core/hub.c:4550 5 locks held by kworker/0:1/12: #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881da227dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d4967200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4967200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881c8a4a200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881c8a4a200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x900 drivers/usb/core/hub.c:2202 #4: ffff8881c8a48190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1165 1 lock held by khungtaskd/23: #0: ffffffff87109060 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x264 kernel/locking/lockdep.c:5331 1 lock held by rsyslogd/1675: #0: ffff8881d03cc860 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:821 2 locks held by getty/1766: #0: ffff8881ce8de090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900008472e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1767: #0: ffff8881cef84090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc9000084f2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1768: #0: ffff8881ce9d2090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900008632e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1769: #0: ffff8881ce850090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900008672e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1770: #0: ffff8881cea27090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc9000085f2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1771: #0: ffff8881ceeb6090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc9000082f2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 5 locks held by kworker/0:5/4540: #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881c967fdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d499e200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d499e200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881c7692200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881c7692200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x900 drivers/usb/core/hub.c:2202 #4: ffff8881c7693190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1165 5 locks held by kworker/1:4/4545: #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8944128 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881ac497dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d4939200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4939200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881d6fff200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881d6fff200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x900 drivers/usb/core/hub.c:2202 #4: ffff8881d4f58190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1165 3 locks held by kworker/0:8/5057: 2 locks held by getty/6113: #0: ffff8881ae25d090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc9000f7c62e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 5.6.0-rc5-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+0xef/0x16e lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1db/0x207 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xa99/0xfd0 kernel/hung_task.c:289 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 1822 Comm: syz-executor.3 Not tainted 5.6.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline] RIP: 0010:hlock_class kernel/locking/lockdep.c:163 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:2879 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:2935 [inline] RIP: 0010:__lock_acquire+0x1459/0x3b60 kernel/locking/lockdep.c:3954 Code: 8b 7c 24 28 e8 d8 15 42 00 41 0f b7 5f 20 66 81 e3 ff 1f 0f b7 db be 08 00 00 00 48 89 d8 48 c1 f8 06 48 8d 3c c5 20 74 33 89 b2 ed 41 00 48 0f a3 1d 0a 6e 0d 08 0f 83 81 06 00 00 48 b9 eb RSP: 0018:ffff8881af5bfbf8 EFLAGS: 00000047 RAX: 0000000000000000 RBX: 0000000000000035 RCX: ffffffff8125f9bb RDX: 1ffff1103a886d4e RSI: 0000000000000008 RDI: ffffffff89337420 RBP: ffff8881d4436200 R08: 0000000000000001 R09: fffffbfff1266e85 R10: fffffbfff1266e84 R11: ffffffff89337427 R12: 0000000044397ae9 R13: ffffffffffffffff R14: ffffffff87e61730 R15: ffff8881d4436a50 FS: 0000000001564940(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc055061000 CR3: 00000001af5b0000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x130/0x340 kernel/locking/lockdep.c:4484 seqcount_lockdep_reader_access include/linux/seqlock.h:81 [inline] read_seqcount_begin include/linux/seqlock.h:164 [inline] ktime_get_ts64+0x86/0x2b0 kernel/time/timekeeping.c:890 posix_get_monotonic_timespec+0x6c/0x250 kernel/time/posix-timers.c:198 __do_sys_clock_gettime kernel/time/posix-timers.c:1091 [inline] __se_sys_clock_gettime kernel/time/posix-timers.c:1081 [inline] __x64_sys_clock_gettime+0x149/0x240 kernel/time/posix-timers.c:1081 do_syscall_64+0xb6/0x5a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45f68a Code: 25 18 00 00 00 00 74 01 f0 48 0f b1 3d df 92 82 00 48 39 c2 75 da f3 c3 0f 1f 84 00 00 00 00 00 48 63 ff b8 e4 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 f3 c3 0f 1f 40 00 48 c7 c2 d4 ff ff ff f7 RSP: 002b:00007ffe6cfba9f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e4 RAX: ffffffffffffffda RBX: 000000000005047e RCX: 000000000045f68a RDX: 0000000000000000 RSI: 00007ffe6cfbaa00 RDI: 0000000000000001 RBP: 0000000000000189 R08: 0000000000000001 R09: 0000000001564940 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe6cfbaa60 R14: 000000000005047e R15: 00007ffe6cfbaa70