syzbot


INFO: task hung in hwrng_unregister

Status: closed as dup on 2019/11/06 12:56
Subsystems: crypto usb
[Documentation on labels]
Reported-by: syzbot+823cb2bdae0c63b2cb9f@syzkaller.appspotmail.com
First crash: 1687d, last: 1626d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
INFO: task hung in chaoskey_disconnect usb crypto C 1222 1441d 1581d
Discussions (2)
Title Replies (including bot) Last reply
INFO: task hung in hwrng_unregister 1 (2) 2019/11/06 12:56
Reminder: 67 open syzbot bugs in usb subsystem 1 (1) 2019/07/24 01:35

Sample crash report:
INFO: task kworker/0:0:5 blocked for more than 143 seconds.
      Not tainted 5.3.0+ #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/0:0     D25832     5      2 0x80004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 schedule+0xca/0x250 kernel/sched/core.c:4123
 schedule_timeout+0x682/0xb20 kernel/time/timer.c:1869
 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+0x10c/0x600 kernel/kthread.c:559
 hwrng_unregister+0x190/0x210 drivers/char/hw_random/core.c:538
 chaoskey_disconnect+0x1b2/0x200 drivers/usb/misc/chaoskey.c:231
 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423
 __device_release_driver drivers/base/dd.c:1134 [inline]
 device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1165
 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:532
 device_del+0x420/0xb10 drivers/base/core.c:2375
 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237
 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2199
 hub_port_connect drivers/usb/core/hub.c:4949 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
 port_event drivers/usb/core/hub.c:5359 [inline]
 hub_event+0x1454/0x3640 drivers/usb/core/hub.c:5441
 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
 process_scheduled_works kernel/workqueue.c:2331 [inline]
 worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
INFO: task kworker/1:0:17 blocked for more than 143 seconds.
      Not tainted 5.3.0+ #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/1:0     D25808    17      2 0x80004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 schedule+0xca/0x250 kernel/sched/core.c:4123
 schedule_timeout+0x682/0xb20 kernel/time/timer.c:1869
 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+0x10c/0x600 kernel/kthread.c:559
 hwrng_unregister+0x190/0x210 drivers/char/hw_random/core.c:538
 chaoskey_disconnect+0x1b2/0x200 drivers/usb/misc/chaoskey.c:231
 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423
 __device_release_driver drivers/base/dd.c:1134 [inline]
 device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1165
 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:532
 device_del+0x420/0xb10 drivers/base/core.c:2375
 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237
 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2199
 hub_port_connect drivers/usb/core/hub.c:4949 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
 port_event drivers/usb/core/hub.c:5359 [inline]
 hub_event+0x1454/0x3640 drivers/usb/core/hub.c:5441
 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
 process_scheduled_works kernel/workqueue.c:2331 [inline]
 worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
INFO: task kworker/1:2:83 blocked for more than 143 seconds.
      Not tainted 5.3.0+ #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/1:2     D26096    83      2 0x80004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 schedule+0xca/0x250 kernel/sched/core.c:4123
 schedule_timeout+0x682/0xb20 kernel/time/timer.c:1869
 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+0x10c/0x600 kernel/kthread.c:559
 hwrng_unregister+0x190/0x210 drivers/char/hw_random/core.c:538
 chaoskey_disconnect+0x1b2/0x200 drivers/usb/misc/chaoskey.c:231
 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423
 __device_release_driver drivers/base/dd.c:1134 [inline]
 device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1165
 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:532
 device_del+0x420/0xb10 drivers/base/core.c:2375
 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237
 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2199
 hub_port_connect drivers/usb/core/hub.c:4949 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
 port_event drivers/usb/core/hub.c:5359 [inline]
 hub_event+0x1454/0x3640 drivers/usb/core/hub.c:5441
 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
 process_scheduled_works kernel/workqueue.c:2331 [inline]
 worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
INFO: task kworker/0:1:1738 blocked for more than 144 seconds.
      Not tainted 5.3.0+ #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/0:1     D26096  1738      2 0x80004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 schedule+0xca/0x250 kernel/sched/core.c:4123
 schedule_timeout+0x682/0xb20 kernel/time/timer.c:1869
 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+0x10c/0x600 kernel/kthread.c:559
 hwrng_unregister+0x190/0x210 drivers/char/hw_random/core.c:538
 chaoskey_disconnect+0x1b2/0x200 drivers/usb/misc/chaoskey.c:231
 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423
 __device_release_driver drivers/base/dd.c:1134 [inline]
 device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1165
 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:532
 device_del+0x420/0xb10 drivers/base/core.c:2375
 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237
 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2199
 hub_port_connect drivers/usb/core/hub.c:4949 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
 port_event drivers/usb/core/hub.c:5359 [inline]
 hub_event+0x1454/0x3640 drivers/usb/core/hub.c:5441
 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
 process_scheduled_works kernel/workqueue.c:2331 [inline]
 worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
INFO: task kworker/1:1:1739 blocked for more than 144 seconds.
      Not tainted 5.3.0+ #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/1:1     D25808  1739      2 0x80004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 schedule+0xca/0x250 kernel/sched/core.c:4123
 schedule_timeout+0x682/0xb20 kernel/time/timer.c:1869
 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+0x10c/0x600 kernel/kthread.c:559
 hwrng_unregister+0x190/0x210 drivers/char/hw_random/core.c:538
 chaoskey_disconnect+0x1b2/0x200 drivers/usb/misc/chaoskey.c:231
 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423
 __device_release_driver drivers/base/dd.c:1134 [inline]
 device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1165
 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:532
 device_del+0x420/0xb10 drivers/base/core.c:2375
 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237
 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2199
 hub_port_connect drivers/usb/core/hub.c:4949 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
 port_event drivers/usb/core/hub.c:5359 [inline]
 hub_event+0x1454/0x3640 drivers/usb/core/hub.c:5441
 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
 process_scheduled_works kernel/workqueue.c:2331 [inline]
 worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
 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: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240
 #1: ffff8881da1c7dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244
 #2: ffff8881d5ca7080 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
 #2: ffff8881d5ca7080 (&dev->mutex){....}, at: hub_event+0x17c/0x3640 drivers/usb/core/hub.c:5387
 #3: ffff8881d7491300 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
 #3: ffff8881d7491300 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2190
 #4: ffff8881d5b9c590 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162
5 locks held by kworker/1:0/17:
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240
 #1: ffff8881da24fdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244
 #2: ffff8881d5d16800 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
 #2: ffff8881d5d16800 (&dev->mutex){....}, at: hub_event+0x17c/0x3640 drivers/usb/core/hub.c:5387
 #3: ffff8881d3355700 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
 #3: ffff8881d3355700 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2190
 #4: ffff8881d3356790 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162
1 lock held by khungtaskd/23:
 #0: ffffffff86cff360 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:5335
5 locks held by kworker/1:2/83:
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240
 #1: ffff8881d93dfdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244
 #2: ffff8881d5c4bd80 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
 #2: ffff8881d5c4bd80 (&dev->mutex){....}, at: hub_event+0x17c/0x3640 drivers/usb/core/hub.c:5387
 #3: ffff8881d96bd700 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
 #3: ffff8881d96bd700 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2190
 #4: ffff8881d96bac10 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162
5 locks held by kworker/0:2/102:
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240
 #1: ffff8881d5eb7dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244
 #2: ffff8881d5d12c80 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
 #2: ffff8881d5d12c80 (&dev->mutex){....}, at: hub_event+0x17c/0x3640 drivers/usb/core/hub.c:5387
 #3: ffff8881cdaf5700 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
 #3: ffff8881cdaf5700 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2190
 #4: ffff8881cdaf5f10 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162
1 lock held by rsyslogd/1605:
 #0: ffff8881d6210ae0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:801
2 locks held by getty/1695:
 #0: ffff8881d913c490 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
 #1: ffffc900004692e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
2 locks held by getty/1696:
 #0: ffff8881d912cd10 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
 #1: ffffc900004892e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
2 locks held by getty/1697:
 #0: ffff8881d913cd10 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
 #1: ffffc9000046d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
2 locks held by getty/1698:
 #0: ffff8881d67acd10 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
 #1: ffffc9000048d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
2 locks held by getty/1699:
 #0: ffff8881d67ac490 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
 #1: ffffc900004852e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
2 locks held by getty/1700:
 #0: ffff8881d9154d10 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
 #1: ffffc900004612e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
2 locks held by getty/1701:
 #0: ffff8881d9156690 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
 #1: ffffc900004552e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156
5 locks held by kworker/0:1/1738:
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240
 #1: ffff8881d290fdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244
 #2: ffff8881d5c4f900 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
 #2: ffff8881d5c4f900 (&dev->mutex){....}, at: hub_event+0x17c/0x3640 drivers/usb/core/hub.c:5387
 #3: ffff8881d7491b80 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
 #3: ffff8881d7491b80 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2190
 #4: ffff8881d5ef7010 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162
5 locks held by kworker/1:1/1739:
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline]
 #0: ffff8881d92103a8 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240
 #1: ffff8881d3287dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244
 #2: ffff8881d5ca3500 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
 #2: ffff8881d5ca3500 (&dev->mutex){....}, at: hub_event+0x17c/0x3640 drivers/usb/core/hub.c:5387
 #3: ffff8881d27c3500 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline]
 #3: ffff8881d27c3500 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2190
 #4: ffff8881d27c3d10 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 23 Comm: khungtaskd Not tainted 5.3.0+ #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+0xca/0x13e lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x55/0x96 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1b0/0x1c7 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+0x9a4/0xe50 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 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline]
NMI backtrace for cpu 1 skipped: idling at default_idle+0x28/0x2e0 arch/x86/kernel/process.c:580

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/09/21 19:17 https://github.com/google/kasan.git usb-fuzzer e0bd8d794fc9 d96e88f3 .config console log report syz C ci2-upstream-usb
2019/07/23 04:43 https://github.com/google/kasan.git usb-fuzzer 6a3599ceaa39 55e0c077 .config console log report syz C ci2-upstream-usb
2019/07/22 22:20 https://github.com/google/kasan.git usb-fuzzer 6a3599ceaa39 55e0c077 .config console log report ci2-upstream-usb
* Struck through repros no longer work on HEAD.