INFO: task kworker/0:0:9 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:0 state:D stack:20616 pid:9 tgid:9 ppid:2 task_flags:0x4288060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145d/0x4a00 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 rpm_resume+0x587/0x12f0 drivers/base/power/runtime.c:859 rpm_resume+0x72f/0x12f0 drivers/base/power/runtime.c:917 __pm_runtime_resume+0xb6/0x170 drivers/base/power/runtime.c:1197 pm_runtime_get_active include/linux/pm_runtime.h:520 [inline] pm_runtime_resume_and_get include/linux/pm_runtime.h:539 [inline] usb_autopm_get_interface+0x20/0xe0 drivers/usb/core/driver.c:1864 aqc111_write_cmd drivers/net/usb/aqc111.c:132 [inline] aqc111_write32_cmd drivers/net/usb/aqc111.c:180 [inline] aqc111_suspend+0x7f8/0xb20 drivers/net/usb/aqc111.c:1409 usb_suspend_interface drivers/usb/core/driver.c:1323 [inline] usb_suspend_both+0x302/0xca0 drivers/usb/core/driver.c:1445 usb_runtime_suspend+0x49/0x180 drivers/usb/core/driver.c:1997 __rpm_callback+0xc8/0x610 drivers/base/power/runtime.c:406 rpm_callback+0xea/0x200 drivers/base/power/runtime.c:457 rpm_suspend+0x2e1/0x11b0 drivers/base/power/runtime.c:698 __pm_runtime_suspend+0xba/0x1a0 drivers/base/power/runtime.c:1167 pm_runtime_put_sync_autosuspend include/linux/pm_runtime.h:752 [inline] usb_new_device+0x1025/0x1a90 drivers/usb/core/hub.c:2727 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x31bf/0x5420 drivers/usb/core/hub.c:5953 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Showing all locks held in the system: 3 locks held by kworker/0:0/9: #0: ffff8881056d9148 ((wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232 #1: ffffc9000009fca0 ((work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233 #2: ffff88810a7b8198 (&dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] ){....}-{4:4}, at: hub_event+0x1be/0x5420 drivers/usb/core/hub.c:5899 1 lock held by khungtaskd/30: #0: ffffffff892cd6e0 ( rcu_read_lock){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] , at: rcu_read_lock include/linux/rcupdate.h:867 [inline] , at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:12/1669: #0: ffff88810e3b7948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0} , at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232 #1: ffffc900027afca0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233 #2: ffffffff8a666c68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8a666c68 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4734 1 lock held by dhcpcd/2898: #0: ffffffff8a666c68 (rtnl_mutex ){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: devinet_ioctl+0x26d/0x1f30 net/ipv4/devinet.c:1120 2 locks held by getty/2921: #0: ffff88810732d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000452f0 (&ldata->atomic_read_lock){+.+.}-{4:4} , at: n_tty_read+0x41b/0x1510 drivers/tty/n_tty.c:2211 6 locks held by kworker/0:6/5283: #0: ffff8881056d9148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232 #1: ffffc90002217ca0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233 #2: ffff88810ab40198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff88810ab40198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1be/0x5420 drivers/usb/core/hub.c:5899 #3: ffff88813a814198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #3: ffff88813a814198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4e0 drivers/base/dd.c:1006 #4: ffff888114566160 (&dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] ){....}-{4:4}, at: __device_attach+0x7e/0x4e0 drivers/base/dd.c:1006 #5: ffffffff8a666c68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline] (rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x50 net/core/dev.c:11504 4 locks held by udevd/5297: #0: ffff88813d3afe80 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12d0 fs/seq_file.c:182 #1: ffff888117a0d888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff88811a7c6e18 (kn->active#23){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff88811a7c6e18 (kn->active#23){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff88813a814198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:900 [inline] #3: ffff88813a814198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 6 locks held by kworker/1:7/7079: #0: ffff8881056d9148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232 #1: ffffc90014677ca0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233 #2: ffff88810a3a8198 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:895 [inline] , at: hub_event+0x1be/0x5420 drivers/usb/core/hub.c:5899 #3: ffff88811a5e5198 ( &dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] ){....}-{4:4}, at: __device_attach+0x7e/0x4e0 drivers/base/dd.c:1006 #4: ffff88810db63160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #4: ffff88810db63160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4e0 drivers/base/dd.c:1006 #5: ffffffff8a666c68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline] #5: ffffffff8a666c68 (rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x50 net/core/dev.c:11504 4 locks held by udevd/8488: #0: ffff88811c3a6790 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12d0 fs/seq_file.c:182 #1: ffff888113c0ec88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff88811eeb0008 (kn->active#23){++++}-{0:0} , at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] , at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff88811ec0f198 (&dev->mutex){....}-{4:4} , at: device_lock_interruptible include/linux/device.h:900 [inline] , at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 7 locks held by kworker/0:5/8614: 6 locks held by kworker/1:0/10816: #0: ffff8881056d9148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232 #1: ffffc900157f7ca0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233 #2: ffff88810a728198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff88810a728198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1be/0x5420 drivers/usb/core/hub.c:5899 #3: ffff88811ec0f198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #3: ffff88811ec0f198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4e0 drivers/base/dd.c:1006 #4: ffff88810db61160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #4: ffff88810db61160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4e0 drivers/base/dd.c:1006 #5: ffffffff8a666c68 (rtnl_mutex){+.+.}-{4:4}, at: wpan_phy_register+0x27/0x160 net/ieee802154/core.c:145 3 locks held by kworker/0:10/13478: #0: ffff888100072948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232 #1: ffffc90014c0fca0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233 #2: ffffffff8a666c68 (rtnl_mutex){+.+.}-{4:4} , at: reg_check_chans_work+0x91/0x1190 net/wireless/reg.c:2453 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x133/0x180 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xe66/0x1180 kernel/hung_task.c:515 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8614 Comm: kworker/0:5 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events legacy_dvb_usb_read_remote_control RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:401 Code: 7f 9b fe 48 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 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c e9 4d 79 75 04 e8 e8 4b fd fe eb a2 e8 71 4c RSP: 0018:ffffc90014757648 EFLAGS: 00000006 RAX: dffffc0000000005 RBX: 00000000000003f9 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: ffffffff82e46ce0 RDI: ffffffff93c8afc0 RBP: ffffffff93c8af80 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: ffff88811e3d27e8 R12: 0000000000000000 R13: ffffffff93c8afd0 R14: ffffffff93c8af80 R15: ffffffff93c8b240 FS: 0000000000000000(0000) GS:ffff888268bf4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c386673 CR3: 00000001242c8000 CR4: 00000000003506f0 Call Trace: serial_port_in include/linux/serial_core.h:806 [inline] serial8250_console_write+0x249/0x1890 drivers/tty/serial/8250/8250_port.c:3306 console_emit_next_record kernel/printk/printk.c:3129 [inline] console_flush_one_record+0x796/0xc60 kernel/printk/printk.c:3215 console_flush_all kernel/printk/printk.c:3289 [inline] __console_flush_and_unlock kernel/printk/printk.c:3319 [inline] console_unlock+0xef/0x240 kernel/printk/printk.c:3359 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426 _printk+0xc7/0x100 kernel/printk/printk.c:2451 m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline] m920x_rc_query+0x496/0x770 drivers/media/usb/dvb-usb/m920x.c:193 legacy_dvb_usb_read_remote_control+0x10c/0x4f0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246