INFO: task kworker/0:15:26068 blocked for more than 143 seconds. Not tainted 6.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:15 state:D stack:24480 pid:26068 ppid:2 flags:0x00004000 Workqueue: events console_callback Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0xc79/0x30a0 kernel/sched/core.c:6695 schedule+0xe7/0x1b0 kernel/sched/core.c:6771 schedule_timeout+0x278/0x2c0 kernel/time/timer.c:2143 ___down_common kernel/locking/semaphore.c:225 [inline] __down_common+0x327/0x6c0 kernel/locking/semaphore.c:246 down+0x74/0xa0 kernel/locking/semaphore.c:63 console_lock+0x96/0x150 kernel/printk/printk.c:2652 console_callback+0x63/0x4c0 drivers/tty/vt/vt.c:2933 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Showing all locks held in the system: 7 locks held by kworker/1:1/26: 1 lock held by khungtaskd/29: #0: ffffffff87eac820 ( rcu_read_lock ){....}-{1:2} , at: rcu_lock_acquire include/linux/rcupdate.h:303 [inline] , at: rcu_read_lock include/linux/rcupdate.h:749 [inline] , at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6613 2 locks held by getty/2443: #0: ffff8881022430a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc5/0x1480 drivers/tty/n_tty.c:2206 2 locks held by kworker/1:4/5276: 6 locks held by kworker/0:6/5306: 4 locks held by udevd/13847: #0: ffff888140317540 (&p->lock ){+.+.}-{3:3}, at: seq_read_iter+0xda/0x1280 fs/seq_file.c:182 #1: ffff888111a57888 ( &of->mutex){+.+.}-{3:3} , at: kernfs_seq_start+0x4b/0x460 fs/kernfs/file.c:154 #2: ffff88810c7791d8 (kn->active#33){++++}-{0:0}, at: kernfs_seq_start+0x6f/0x460 fs/kernfs/file.c:155 #3: ffff888100f4d190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:997 [inline] (&dev->mutex){....}-{3:3}, at: serial_show+0x26/0xa0 drivers/usb/core/sysfs.c:143 2 locks held by kworker/0:10/16350: 7 locks held by kworker/1:12/20496: 2 locks held by kworker/0:15/26068: #0: ffff888100070d38 ( (wq_completion)events){+.+.}-{0:0} , at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605 #1: ffffc9000f50fd80 (console_work ){+.+.}-{0:0} , at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2606 5 locks held by kworker/1:2/26570: #0: ffff88810aa43d38 ((wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605 #1: ffffc9001130fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2606 #2: ffff888106361190 (&dev->mutex ){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] ){....}-{3:3}, at: hub_event+0x1be/0x4f30 drivers/usb/core/hub.c:5768 #3: ffff888106364500 (&port_dev->status_lock ){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3138 [inline] ){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5337 [inline] ){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5580 [inline] ){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5740 [inline] ){+.+.}-{3:3}, at: hub_event+0x28b4/0x4f30 drivers/usb/core/hub.c:5822 #4: ffff888104706768 ( hcd->address0_mutex){+.+.}-{3:3} , at: hub_port_connect drivers/usb/core/hub.c:5338 [inline] , at: hub_port_connect_change drivers/usb/core/hub.c:5580 [inline] , at: port_event drivers/usb/core/hub.c:5740 [inline] , at: hub_event+0x28da/0x4f30 drivers/usb/core/hub.c:5822 6 locks held by kworker/0:17/27463: #0: ffff88810aa43d38 ((wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605 #1: ffffc900042dfd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2606 #2: ffff888105fe2190 ( &dev->mutex ){....}-{3:3} , at: device_lock include/linux/device.h:992 [inline] , at: hub_event+0x1be/0x4f30 drivers/usb/core/hub.c:5768 #3: ffff888100f4d190 ( &dev->mutex){....}-{3:3} , at: device_lock include/linux/device.h:992 [inline] , at: usb_disconnect+0x10a/0x890 drivers/usb/core/hub.c:2243 #4: ffff88810c3cc160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:992 [inline] #4: ffff88810c3cc160 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff88810c3cc160 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1292 #5: ffffffff88faeca8 (rtnl_mutex){+.+.}-{3:3}, at: unregister_netdev+0x12/0x30 net/core/dev.c:11011 1 lock held by syz-executor.5/28915: #0: ffffffff87eb80f8 ( rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x404/0x7e0 kernel/rcu/tree_exp.h:992 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.6.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x277/0x380 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x26c/0x2d0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf87/0x1210 kernel/hung_task.c:379 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Sending NMI from CPU 0 to CPUs 1: cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes NMI backtrace for cpu 1 CPU: 1 PID: 5276 Comm: kworker/1:4 Not tainted 6.6.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Workqueue: events legacy_dvb_usb_read_remote_control RIP: 0010:io_serial_out+0x90/0xb0 drivers/tty/serial/8250/8250_port.c:424 Code: 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 18 66 03 5d 40 44 89 e8 89 da ee 5b <5d> 41 5c 41 5d c3 e8 e5 52 15 ff eb a4 e8 3e 53 15 ff eb e1 66 66 RSP: 0018:ffffc900001983e8 EFLAGS: 00000006 RAX: 0000000000000000 RBX: ffffffff8c156ea0 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: ffffffff82849455 RDI: ffffffff8c156ee0 RBP: ffffffff8c156ea0 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 205d313339383154 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8c156ef0 R15: 0000000000000052 FS: 0000000000000000(0000) GS:ffff8881f6700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f12932013b0 CR3: 000000013ebb4000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_out drivers/tty/serial/8250/8250.h:122 [inline] serial8250_clear_IER+0x98/0xb0 drivers/tty/serial/8250/8250_port.c:717 serial8250_console_write+0x1e9/0x1060 drivers/tty/serial/8250/8250_port.c:3414 console_emit_next_record kernel/printk/printk.c:2910 [inline] console_flush_all+0x4eb/0xfb0 kernel/printk/printk.c:2966 console_unlock+0x10c/0x260 kernel/printk/printk.c:3035 vprintk_emit+0x17f/0x5f0 kernel/printk/printk.c:2307 dev_vprintk_emit drivers/base/core.c:4849 [inline] dev_printk_emit+0xfb/0x140 drivers/base/core.c:4860 __dev_printk+0xf5/0x270 drivers/base/core.c:4872 _dev_err+0xe5/0x120 drivers/base/core.c:4915 wdm_int_callback+0x7d1/0xaa0 drivers/usb/class/cdc-wdm.c:276 __usb_hcd_giveback_urb+0x359/0x5c0 drivers/usb/core/hcd.c:1650 usb_hcd_giveback_urb+0x389/0x430 drivers/usb/core/hcd.c:1733 dummy_timer+0x1415/0x35f0 drivers/usb/gadget/udc/dummy_hcd.c:1987 call_timer_fn+0x19e/0x580 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x764/0xb10 kernel/time/timer.c:2022 run_timer_softirq+0x58/0xd0 kernel/time/timer.c:2035 __do_softirq+0x20b/0x94e kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu kernel/softirq.c:632 [inline] irq_exit_rcu+0xa7/0x110 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x8e/0xb0 arch/x86/kernel/apic/apic.c:1074 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:console_flush_all+0x9e0/0xfb0 kernel/printk/printk.c:2972 Code: c6 18 23 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 94 68 1c 00 48 85 db 0f 85 97 03 00 00 e8 f6 6c 1c 00 fb 48 8b 44 24 08 <48> 8b 14 24 0f b6 00 83 e2 07 38 d0 7f 08 84 c0 0f 85 08 05 00 00 RSP: 0018:ffffc90004b7f8e8 EFLAGS: 00000293 RAX: fffff5200096ff48 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888114fa0000 RSI: ffffffff813104ba RDI: 0000000000000007 RBP: dffffc0000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 205d303533363154 R12: ffffffff88353f80 R13: 0000000000000001 R14: ffffffff88353fd8 R15: 0000000000000001 console_unlock+0x10c/0x260 kernel/printk/printk.c:3035 vprintk_emit+0x17f/0x5f0 kernel/printk/printk.c:2307 vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45 _printk+0xc8/0x100 kernel/printk/printk.c:2332 m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline] m920x_rc_query+0x496/0x760 drivers/media/usb/dvb-usb/m920x.c:193 legacy_dvb_usb_read_remote_control+0x107/0x4f0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304