INFO: task kworker/0:2:101 blocked for more than 143 seconds. Not tainted 5.4.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:2 D23096 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: 1 lock held by khungtaskd/22: #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: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2235 #1: ffff8881d50f7dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2239 #2: ffff8881d5606200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1493 [inline] #2: ffff8881d5606200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3860 drivers/usb/core/hub.c:5498 #3: ffff8881d9c1d200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1493 [inline] #3: ffff8881d9c1d200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2191 #4: ffff8881cde5b190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162 1 lock held by rsyslogd/1601: 2 locks held by getty/1692: #0: ffff8881d22c6090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc900004592e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1693: #0: ffff8881d1615090 (&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/1694: #0: ffff8881d15a4090 (&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/1695: #0: ffff8881d1f02090 (&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: ffff8881d1616090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc900004792e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1697: #0: ffff8881d1617090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000047d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1698: #0: ffff8881d22c2090 (&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 3 locks held by kworker/1:5/3279: 3 locks held by kworker/0:6/3510: #0: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8881d8d18528 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2235 #1: ffff8881cb28fdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2239 #2: ffff8881d55b7200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1493 [inline] #2: ffff8881d55b7200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3860 drivers/usb/core/hub.c:5498 6 locks held by kdvb-ca-0:0/4411: 1 lock held by syz-executor.1/6484: #0: ffff8881d120a148 (&evdev->mutex){+.+.}, at: evdev_flush+0x6f/0x140 drivers/input/evdev.c:334 1 lock held by syz-executor.2/6483: 1 lock held by syz-executor.3/6496: #0: ffff8881d120a148 (&evdev->mutex){+.+.}, at: evdev_open_device drivers/input/evdev.c:407 [inline] #0: ffff8881d120a148 (&evdev->mutex){+.+.}, at: evdev_open+0x293/0x510 drivers/input/evdev.c:499 1 lock held by syz-executor.3/6506: #0: ffff8881d120a148 (&evdev->mutex){+.+.}, at: evdev_open_device drivers/input/evdev.c:407 [inline] #0: ffff8881d120a148 (&evdev->mutex){+.+.}, at: evdev_open+0x293/0x510 drivers/input/evdev.c:499 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 22 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4411 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:vsnprintf+0x276/0x14f0 lib/vsprintf.c:2645 Code: e8 5f f6 c9 fb 45 84 f6 0f 85 e9 fe ff ff e8 21 f5 c9 fb 45 89 e5 44 2b 6c 24 20 e8 14 f5 c9 fb 48 8b 5c 24 28 31 ff 48 89 de 95 f6 c9 fb 48 85 db 74 41 e8 fb f4 c9 fb 4c 3b 64 24 10 0f 83 RSP: 0018:ffff8881cea8f7e8 EFLAGS: 00000046 RAX: ffff8881ce6bc980 RBX: 000000000000000c RCX: ffffffff857488d1 RDX: 0000000000000000 RSI: 000000000000000c RDI: 0000000000000000 RBP: ffffffff85c741a4 R08: ffff8881ce6bc980 R09: ffffed1039d51f48 R10: ffffed1039d51f47 R11: ffff8881cea8fa3d R12: ffff8881cea8fa13 R13: 0000000000000003 R14: 0000000000000000 R15: ffff8881cea8f8e8 FS: 0000000000000000(0000) GS:ffff8881db400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020b94000 CR3: 00000001b9001000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: snprintf+0xbb/0xf0 lib/vsprintf.c:2707 print_caller kernel/printk/printk.c:1280 [inline] print_prefix kernel/printk/printk.c:1299 [inline] msg_print_text+0x17e/0x560 kernel/printk/printk.c:1316 console_unlock+0x301/0xc30 kernel/printk/printk.c:2448 vprintk_emit+0x171/0x3d0 kernel/printk/printk.c:1996 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