INFO: task kworker/0:2:101 blocked for more than 145 seconds. Not tainted 5.4.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:2 D22944 101 2 0x80004000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0xcd/0x2b0 kernel/sched/core.c:4155 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+0x160/0x6e0 kernel/kthread.c:559 dvb_ca_en50221_release+0x91/0x1d0 drivers/media/dvb-core/dvb_ca_en50221.c:1934 tt3650_ci_uninit drivers/media/usb/dvb-usb/pctv452e.c:364 [inline] pctv452e_usb_disconnect+0xb0/0xf0 drivers/media/usb/dvb-usb/pctv452e.c:1061 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+0x481/0xd30 drivers/base/core.c:2664 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2200 hub_port_connect drivers/usb/core/hub.c:5035 [inline] hub_port_connect_change drivers/usb/core/hub.c:5324 [inline] port_event drivers/usb/core/hub.c:5470 [inline] hub_event+0x1753/0x3860 drivers/usb/core/hub.c:5552 process_one_work+0x92b/0x1530 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: 6 locks held by kworker/0:0/5: #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2235 #1: ffff8881da5dfdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2239 #2: ffff8881d5672200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1493 [inline] #2: ffff8881d5672200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3860 drivers/usb/core/hub.c:5498 #3: ffff8881d5674540 (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:2997 [inline] #3: ffff8881d5674540 (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5115 [inline] #3: ffff8881d5674540 (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5324 [inline] #3: ffff8881d5674540 (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5470 [inline] #3: ffff8881d5674540 (&port_dev->status_lock){+.+.}, at: hub_event+0x1c67/0x3860 drivers/usb/core/hub.c:5552 #4: ffff8881d5404660 (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b6/0x2d30 drivers/usb/core/hub.c:4539 #5: ffffffff871f0568 (ehci_cf_port_reset_rwsem){.+.+}, at: hub_port_reset+0x17b/0x1460 drivers/usb/core/hub.c:2859 6 locks held by kworker/1:1/22: #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2235 #1: ffff8881d902fdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2239 #2: ffff8881d56b8200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1493 [inline] #2: ffff8881d56b8200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3860 drivers/usb/core/hub.c:5498 #3: ffff8881d059f200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1493 [inline] #3: ffff8881d059f200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2191 #4: ffff8881d10ee190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162 #5: ffffffff86ec3ce0 (registration_lock){+.+.}, at: unregister_framebuffer+0x17/0x30 drivers/video/fbdev/core/fbmem.c:1847 1 lock held by khungtaskd/23: #0: ffffffff86cfe560 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x264 kernel/locking/lockdep.c:5332 5 locks held by kworker/0:2/101: #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8ca4928 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2235 #1: ffff8881d50dfdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2239 #2: ffff8881d564b200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1493 [inline] #2: ffff8881d564b200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3860 drivers/usb/core/hub.c:5498 #3: ffff8881af013200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1493 [inline] #3: ffff8881af013200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2191 #4: ffff8881ae9aa190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162 1 lock held by rsyslogd/1596: #0: ffff8881d3b26ae0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:801 2 locks held by getty/1686: #0: ffff8881d2636090 (&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/1687: #0: ffff8881d1984090 (&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/1688: #0: ffff8881d1730090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc900004812e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1689: #0: ffff8881d196d090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc900004712e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1690: #0: ffff8881d18bb090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc900004752e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1691: #0: ffff8881d1731090 (&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/1692: #0: ffff8881d2634090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000044d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 6 locks held by kworker/0:5/3273: 5 locks held by kworker/0:4/13001: 4 locks held by kdvb-ca-0:0/13508: 6 locks held by kworker/0:8/14824: 1 lock held by syz-executor.1/15892: #0: ffff8881d50c5148 (&evdev->mutex){+.+.}, at: evdev_release+0x7f/0x1c0 drivers/input/evdev.c:455 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 5.4.0-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+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+0xa7c/0xf80 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: 13508 Comm: kdvb-ca-0:0 Not tainted 5.4.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:call_timer_fn+0x0/0x650 kernel/time/timer.c:1381 Code: 5f c3 31 ed eb e2 4c 89 e7 e8 0c e9 36 00 eb be e8 85 e9 36 00 e9 7a ff ff ff e8 7b e9 36 00 e9 4a ff ff ff 66 0f 1f 44 00 00 <41> 57 41 56 41 55 41 54 49 bc 00 00 00 00 00 fc ff df 55 53 48 89 RSP: 0018:ffff8881db509e00 EFLAGS: 00000202 RAX: 0000000000000007 RBX: 0000000000000000 RCX: 0000000000000002 RDX: 000000010000ec32 RSI: ffffffff812f4760 RDI: ffff8881da60fd18 RBP: ffff8881da60fd18 R08: ffff8881d9484980 R09: fffffbfff11aecba R10: fffffbfff11aecb9 R11: ffffffff88d765cf R12: ffff8881db509e78 R13: dffffc0000000000 R14: ffffffff812f4760 R15: ffff8881db525f40 FS: 0000000000000000(0000) GS:ffff8881db500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff2a2d40cdc CR3: 00000001d3216000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x5e3/0x1490 kernel/time/timer.c:1786 __do_softirq+0x221/0x912 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x178/0x1a0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x12f/0x500 arch/x86/kernel/apic/apic.c:1137 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/irqflags.h:85 [inline] RIP: 0010:console_trylock_spinning kernel/printk/printk.c:1751 [inline] RIP: 0010:vprintk_emit+0x3c8/0x3d0 kernel/printk/printk.c:1995 Code: 00 83 fb ff 75 d6 e9 e0 fc ff ff e8 32 b1 15 00 e8 ed ed 1a 00 41 56 9d e9 b6 fd ff ff e8 20 b1 15 00 e8 db ed 1a 00 41 56 9d 2a ff ff ff 0f 1f 00 55 48 89 f5 53 48 89 fb e8 03 b1 15 00 49 RSP: 0018:ffff8881d631fb60 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000007 RBX: 0000000000000200 RCX: 0000000000000006 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8881d94851cc RBP: ffff8881d631fba8 R08: ffff8881d9484980 R09: fffffbfff11aecba R10: fffffbfff11aecb9 R11: ffffffff88d765cf R12: 000000000000002d R13: ffff8881da67c980 R14: 0000000000000293 R15: 0000000000000000 vprintk_func+0x75/0x113 kernel/printk/printk_safe.c:386 printk+0xba/0xed kernel/printk/printk.c:2056 tt3650_ci_msg.cold+0x30/0x3e drivers/media/usb/dvb-usb/pctv452e.c:141 tt3650_ci_msg_locked+0x83/0xb0 drivers/media/usb/dvb-usb/pctv452e.c:157 tt3650_ci_poll_slot_status+0x90/0x110 drivers/media/usb/dvb-usb/pctv452e.c:333 dvb_ca_en50221_check_camstatus+0x102/0x330 drivers/media/dvb-core/dvb_ca_en50221.c:234 dvb_ca_en50221_thread_state_machine drivers/media/dvb-core/dvb_ca_en50221.c:1128 [inline] dvb_ca_en50221_thread+0x26b/0x13e0 drivers/media/dvb-core/dvb_ca_en50221.c:1317 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352