INFO: task kworker/0:3:19181 blocked for more than 143 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:3 D23288 19181 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:2664 usb_disable_device+0x23d/0x790 drivers/usb/core/message.c:1237 usb_disconnect+0x293/0x900 drivers/usb/core/hub.c:2207 hub_port_connect drivers/usb/core/hub.c:5042 [inline] hub_port_connect_change drivers/usb/core/hub.c:5331 [inline] port_event drivers/usb/core/hub.c:5477 [inline] hub_event+0x1a1d/0x4300 drivers/usb/core/hub.c:5559 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264 process_scheduled_works kernel/workqueue.c:2326 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2412 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: 1 lock held by khungtaskd/22: #0: ffffffff87109020 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x264 kernel/locking/lockdep.c:5331 1 lock held by rsyslogd/1678: 2 locks held by getty/1769: #0: ffff8881ced50090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc9000046d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1770: #0: ffff8881cef22090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900004652e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1771: #0: ffff8881ced55090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900004752e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1772: #0: ffff8881ceff0090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900004852e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1773: #0: ffff8881ced02090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc9000047d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by getty/1774: #0: ffff8881cf0e2090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900004552e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 3 locks held by kworker/0:4/4547: 5 locks held by kworker/0:3/19181: #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881ca647dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d4d08200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4d08200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5505 #3: ffff8881ad432200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #3: ffff8881ad432200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x900 drivers/usb/core/hub.c:2198 #4: ffff8881ce8b4190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1165 7 locks held by kworker/1:1/19211: 6 locks held by kworker/1:5/19213: #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8825528 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x82a/0x1620 kernel/workqueue.c:2235 #1: ffff8881ac707dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85e/0x1620 kernel/workqueue.c:2239 #2: ffff8881d4d76200 (&dev->mutex){....}, at: device_lock include/linux/device.h:771 [inline] #2: ffff8881d4d76200 (&dev->mutex){....}, at: hub_event+0x1be/0x4300 drivers/usb/core/hub.c:5505 #3: ffff8881d4d98540 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:3004 [inline] #3: ffff8881d4d98540 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5122 [inline] #3: ffff8881d4d98540 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5331 [inline] #3: ffff8881d4d98540 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5477 [inline] #3: ffff8881d4d98540 (&port_dev->status_lock){+.+.}, at: hub_event+0x1fae/0x4300 drivers/usb/core/hub.c:5559 #4: ffff8881d531d360 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b6/0x2e60 drivers/usb/core/hub.c:4546 #5: ffffffff8767f908 (ehci_cf_port_reset_rwsem){.+.+}, at: hub_port_reset+0x186/0x1790 drivers/usb/core/hub.c:2866 2 locks held by getty/29249: #0: ffff8881d3b9e090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc9000b9cf2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x21d/0x1b30 drivers/tty/n_tty.c:2156 5 locks held by kworker/0:10/29484: 1 lock held by syz-executor.1/31692: 3 locks held by syz-executor.2/31719: 3 locks held by syz-executor.2/31720: #0: ffff8881b84a00e0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:821 #1: ffff8881d47bc410 (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2903 [inline] #1: ffff8881d47bc410 (sb_writers#3){.+.+}, at: vfs_write+0x474/0x5c0 fs/read_write.c:557 #2: ffff8881a5be5d58 (&sb->s_type->i_mutex_key#10){++++}, at: inode_lock include/linux/fs.h:791 [inline] #2: ffff8881a5be5d58 (&sb->s_type->i_mutex_key#10){++++}, at: ext4_dio_write_iter fs/ext4/file.c:482 [inline] #2: ffff8881a5be5d58 (&sb->s_type->i_mutex_key#10){++++}, at: ext4_file_write_iter+0x4b7/0x1780 fs/ext4/file.c:640 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 22 Comm: khungtaskd Not tainted 5.6.0-rc3-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: 31719 Comm: syz-executor.2 Not tainted 5.6.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_memory_region+0x12a/0x1c0 mm/kasan/generic.c:193 Code: 89 c8 4d 39 c8 74 0f 41 80 38 00 74 ee 49 8d 04 1c 4d 85 c0 75 32 49 89 e9 49 29 c1 e9 4a ff ff ff 5b b8 01 00 00 00 5d 41 5c 4d 85 c9 74 f1 49 01 d9 eb 09 48 83 c0 01 4c 39 c8 74 e3 80 38 RSP: 0018:ffff8881db309b88 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000084 RCX: ffffffff81260d31 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff89336430 RBP: ffff8881c853e200 R08: 0000000000000001 R09: fffffbfff1266c87 R10: fffffbfff1266c86 R11: ffffffff89336437 R12: 0000000083ba1ce8 R13: 7c314e3d56f52def R14: ffffffff87e60f70 R15: ffff8881c853eb18 FS: 00007f3b11f67700(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020c8a1ff CR3: 00000001d9532000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline] hlock_class kernel/locking/lockdep.c:163 [inline] __lock_acquire+0x16a1/0x3b60 kernel/locking/lockdep.c:3950 lock_acquire+0x130/0x340 kernel/locking/lockdep.c:4484 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x27/0x40 kernel/locking/spinlock.c:151 rq_lock kernel/sched/sched.h:1215 [inline] ttwu_queue kernel/sched/core.c:2403 [inline] try_to_wake_up+0xa5e/0x1690 kernel/sched/core.c:2639 hrtimer_wakeup+0x43/0x60 kernel/time/hrtimer.c:1769 __run_hrtimer kernel/time/hrtimer.c:1517 [inline] __hrtimer_run_queues+0x32c/0xd20 kernel/time/hrtimer.c:1579 hrtimer_interrupt+0x2e8/0x730 kernel/time/hrtimer.c:1641 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1119 [inline] smp_apic_timer_interrupt+0xfe/0x540 arch/x86/kernel/apic/apic.c:1144 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:debug_lockdep_rcu_enabled kernel/rcu/update.c:251 [inline] RIP: 0010:debug_lockdep_rcu_enabled+0xa9/0xe0 kernel/rcu/update.c:249 Code: 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 32 8b 93 4c 08 00 00 <31> c0 5b 85 d2 0f 94 c0 c3 31 c0 5b c3 48 c7 c7 e0 00 e6 87 e8 ae RSP: 0018:ffff8881c75777b0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000007 RBX: ffff8881c853e200 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff8881c853ea4c RBP: 0000000000000000 R08: ffff8881c853e200 R09: ffffed103b666a84 R10: ffffed103b666a83 R11: ffff8881db33541b R12: 000000000000000e R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000c88000 rcu_read_unlock include/linux/rcupdate.h:651 [inline] find_get_entry+0x3f8/0x810 mm/filemap.c:1535 pagecache_get_page+0x47/0x9f0 mm/filemap.c:1613 grab_cache_page_write_begin+0x6d/0xa0 mm/filemap.c:3237 ext4_da_write_begin+0x2c8/0xc30 fs/ext4/inode.c:2966 generic_perform_write+0x20a/0x4f0 mm/filemap.c:3287 ext4_buffered_write_iter+0x235/0x4a0 fs/ext4/file.c:270 ext4_file_write_iter+0x1a1/0x1780 fs/ext4/file.c:642 call_write_iter include/linux/fs.h:1901 [inline] new_sync_write+0x420/0x650 fs/read_write.c:483 __vfs_write+0xc9/0x100 fs/read_write.c:496 vfs_write+0x262/0x5c0 fs/read_write.c:558 ksys_write+0x127/0x250 fs/read_write.c:611 do_syscall_64+0xb6/0x5a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c679 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f3b11f66c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f3b11f676d4 RCX: 000000000045c679 RDX: 00000000ffffff45 RSI: 0000000020001200 RDI: 0000000000000007 RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000ce8 R14: 00000000004ceee2 R15: 000000000076bf0c