INFO: task kworker/1:0:17 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/1:0 D23320 17 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/1:0/17: #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881da267dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d48e1200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d48e1200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881c570d200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881c570d200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x900 drivers/usb/core/hub.c:2202 #4: ffff8881d3c8a190 (&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/1679: 2 locks held by getty/1770: #0: ffff8881cf1fd090 (&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/1771: #0: ffff8881d1516090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900008772e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1772: #0: ffff8881ce728090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900008912e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1773: #0: ffff8881d1f1c090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc9000087f2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1774: #0: ffff8881ce0d2090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900008872e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1775: #0: ffff8881cebcb090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900008732e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1776: #0: ffff8881cf1fb090 (&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 kworker/u4:3/1826: #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881da029928 ((wq_completion)events_unbound){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881ae227dd0 ((reaper_work).work){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 6 locks held by kworker/0:5/4565: 6 locks held by kworker/1:3/4576: #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881d57bfdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d49ad200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d49ad200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881d49af540 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:3008 [inline] #3: ffff8881d49af540 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5126 [inline] #3: ffff8881d49af540 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] #3: ffff8881d49af540 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5481 [inline] #3: ffff8881d49af540 (&port_dev->status_lock){+.+.}, at: hub_event+0x1fae/0x4300 drivers/usb/core/hub.c:5563 #4: ffff8881d4c3fd60 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b6/0x2e60 drivers/usb/core/hub.c:4550 #5: ffffffff8767fb08 (ehci_cf_port_reset_rwsem){.+.+}, at: hub_port_reset+0x186/0x1790 drivers/usb/core/hub.c:2870 6 locks held by kworker/1:5/4622: #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8ec6d28 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881d1de7dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d49d4200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d49d4200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5509 #3: ffff8881d49d6540 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:3008 [inline] #3: ffff8881d49d6540 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5126 [inline] #3: ffff8881d49d6540 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] #3: ffff8881d49d6540 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5481 [inline] #3: ffff8881d49d6540 (&port_dev->status_lock){+.+.}, at: hub_event+0x1fae/0x4300 drivers/usb/core/hub.c:5563 #4: ffff8881d4c3ff60 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b6/0x2e60 drivers/usb/core/hub.c:4550 #5: ffffffff8767fb08 (ehci_cf_port_reset_rwsem){.+.+}, at: hub_port_reset+0x186/0x1790 drivers/usb/core/hub.c:2870 5 locks held by kworker/0:8/10674: ============================================= 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: 12831 Comm: syz-executor.1 Not tainted 5.6.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x9/0x60 kernel/kcov.c:197 Code: cc 65 48 8b 04 25 00 0f 02 00 48 8b 80 c8 12 00 00 c3 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 65 48 8b 04 25 00 0f 02 00 <65> 8b 15 d8 b8 c2 7e f7 c2 00 01 1f 00 48 8b 34 24 74 0e 80 e6 01 RSP: 0018:ffff8881ca637728 EFLAGS: 00000202 RAX: ffff8881d0dfb100 RBX: 0000000000000000 RCX: ffffffff815bb8c9 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000001 R08: ffff8881d0dfb100 R09: ffffed103a1bf621 R10: ffffed103a1bf620 R11: ffff8881d0dfb107 R12: ffff8881ca637a10 R13: 80000001b4e64007 R14: dffffc0000000000 R15: 00007fdeb14e5000 FS: 0000000000000000(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004d8718 CR3: 0000000007021000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: zap_pte_range mm/memory.c:1053 [inline] zap_pmd_range mm/memory.c:1184 [inline] zap_pud_range mm/memory.c:1213 [inline] zap_p4d_range mm/memory.c:1234 [inline] unmap_page_range+0xae5/0x2120 mm/memory.c:1255 unmap_single_vma+0x196/0x300 mm/memory.c:1300 unmap_vmas+0x174/0x2f0 mm/memory.c:1332 exit_mmap+0x278/0x4d0 mm/mmap.c:3126 __mmput kernel/fork.c:1082 [inline] mmput+0xce/0x3d0 kernel/fork.c:1103 exit_mm kernel/exit.c:485 [inline] do_exit+0xa83/0x2c80 kernel/exit.c:788 do_group_exit+0x125/0x340 kernel/exit.c:899 get_signal+0x480/0x2470 kernel/signal.c:2739 do_signal+0x88/0x1490 arch/x86/kernel/signal.c:813 exit_to_usermode_loop+0x1a2/0x200 arch/x86/entry/common.c:160 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x4e0/0x5a0 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c6b7 Code: Bad RIP value. RSP: 002b:00007fdeb08c0bc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: fffffffffffffffc RBX: 0000000020000300 RCX: 000000000045c6b7 RDX: 00007fdeb08c1c10 RSI: 0000000080085502 RDI: 0000000000000003 RBP: 000000000076bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 00007fdeb08c39d0 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000c26 R14: 00000000004ce54a R15: 000000000076bfac