INFO: task kworker/1:2:2791 blocked for more than 143 seconds. Not tainted 6.16.0-syzkaller-12288-g2b38afce25c4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:2 state:D stack:21944 pid:2791 tgid:2791 ppid:2 task_flags:0x4288060 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x12fc/0x3b90 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x82a/0x10b0 kernel/locking/mutex.c:760 rtnl_net_lock include/linux/rtnetlink.h:130 [inline] rtnl_net_dev_lock+0x146/0x360 net/core/dev.c:2142 unregister_netdev+0x15/0x60 net/core/dev.c:12228 usbnet_disconnect+0x109/0x500 drivers/net/usb/usbnet.c:1658 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:571 [inline] device_remove+0x125/0x170 drivers/base/dd.c:563 __device_release_driver drivers/base/dd.c:1274 [inline] device_release_driver_internal+0x44b/0x620 drivers/base/dd.c:1297 bus_remove_device+0x22f/0x420 drivers/base/bus.c:579 device_del+0x396/0x9f0 drivers/base/core.c:3878 usb_disable_device+0x355/0x7d0 drivers/usb/core/message.c:1418 usb_disconnect+0x2e1/0x9c0 drivers/usb/core/hub.c:2344 hub_port_connect drivers/usb/core/hub.c:5406 [inline] hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] port_event drivers/usb/core/hub.c:5870 [inline] hub_event+0x1aa2/0x5060 drivers/usb/core/hub.c:5952 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5b6/0x6c0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 6 locks held by kworker/0:0/9: #0: ffff8881066f3d48 ( (wq_completion)usb_hub_wq){+.+.}-{0:0} , at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc9000009fd10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff88810bb56198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #2: ffff88810bb56198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1be/0x5060 drivers/usb/core/hub.c:5898 #3: ffff88811caf4198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006 #4: ffff888111c65160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006 #5: ffffffff8a5f9348 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline] #5: ffffffff8a5f9348 (rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x50 net/core/dev.c:11302 3 locks held by kworker/u8:0/12: #0: ffff8881121e4948 ((wq_completion)ipv6_addrconf ){+.+.}-{0:0} , at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc900000cfd10 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffffffff8a5f9348 (rtnl_mutex ){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4734 1 lock held by khungtaskd/30: #0: ffffffff892c7320 (rcu_read_lock ){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] , at: rcu_read_lock include/linux/rcupdate.h:841 [inline] , at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 6 locks held by kworker/1:2/2791: #0: ffff8881066f3d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc900042dfd10 ((work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff88810b3c6198 (&dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] ){....}-{4:4}, at: hub_event+0x1be/0x5060 drivers/usb/core/hub.c:5898 #3: ffff88811f980198 (&dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:911 [inline] , at: usb_disconnect+0x10a/0x9c0 drivers/usb/core/hub.c:2335 #4: ffff88813a379160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #4: ffff88813a379160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1096 [inline] #4: ffff88813a379160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xa4/0x620 drivers/base/dd.c:1294 #5: ffffffff8a5f9348 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] ffffffff8a5f9348 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x146/0x360 net/core/dev.c:2142 1 lock held by dhcpcd/2884: 2 locks held by getty/2907: #0: ffff8881123910a0 (&tty->ldisc_sem ){++++}-{0:0} , at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{4:4} , at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 4 locks held by udevd/5184: #0: ffff88811bf09d58 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182 #1: ffff8881349bb088 ( &of->mutex #2){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888113afc008 (kn->active#16){++++}-{0:0} , at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88810a727198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:916 [inline] #3: ffff88810a727198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 6 locks held by kworker/0:3/5209: #0: ffff8881066f3d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0} , at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc90004207d10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff88810b3a8198 ( &dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] ){....}-{4:4}, at: hub_event+0x1be/0x5060 drivers/usb/core/hub.c:5898 #3: ffff88811f843198 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:911 [inline] , at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006 #4: ffff888129e9b160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #4: ffff888129e9b160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006 #5: ffffffff8a5f9348 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline] ffffffff8a5f9348 (rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x50 net/core/dev.c:11302 4 locks held by kworker/0:4/5210: 4 locks held by udevd/5215: #0: ffff888145559790 ( &p->lock){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182 #1: ffff8881180c8088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888136533968 (kn->active#16){++++}-{0:0} , at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88811caf4198 ( &dev->mutex ){....}-{4:4} , at: device_lock_interruptible include/linux/device.h:916 [inline] , at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 6 locks held by kworker/1:3/5230: 6 locks held by kworker/1:5/5236: #0: ffff8881066f3d48 ((wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc90004337d10 ( (work_completion)(&hub->events) ){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffff88810b79e198 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:911 [inline] , at: hub_event+0x1be/0x5060 drivers/usb/core/hub.c:5898 #3: ffff88810a727198 (&dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:911 [inline] , at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006 #4: ffff888113585160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006 #5: ffffffff8a5f9348 (rtnl_mutex){+.+.}-{4:4} , at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline] , at: register_netdev+0x18/0x50 net/core/dev.c:11302 4 locks held by udevd/5347: #0: ffff8881195c02f0 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182 #1: ffff888137cec888 (&of->mutex#2 ){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff8881195c2d28 (kn->active#16){++++}-{0:0} , at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88811f843198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:916 [inline] #3: ffff88811f843198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.16.0-syzkaller-12288-g2b38afce25c4 #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf0e/0x1260 kernel/hung_task.c:491 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5b6/0x6c0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 15721 Comm: kworker/0:9 Not tainted 6.16.0-syzkaller-12288-g2b38afce25c4 #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: events legacy_dvb_usb_read_remote_control RIP: 0010:__hrtimer_run_queues+0x0/0xad0 kernel/time/hrtimer.c:1795 Code: c6 41 71 00 eb c3 48 89 34 24 e8 bb 41 71 00 48 8b 34 24 eb d3 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <41> 57 41 56 49 89 fe 41 55 41 89 cd 41 54 49 bc 00 00 00 00 00 fc RSP: 0018:ffffc90000007f28 EFLAGS: 00000046 RAX: 0000000080010002 RBX: dffffc0000000000 RCX: 000000000000000f RDX: 0000000000000046 RSI: 0000017d1ff84929 RDI: ffff8881f5827a40 RBP: 0000017d1ff84929 R08: 0000000000000006 R09: 7fffffffffffffff R10: 0000017d1ff84929 R11: 0000000000000000 R12: 7fffffffffffffff R13: ffff8881f5827a8c R14: 0000000000000000 R15: ffff8881f5827a40 FS: 0000000000000000(0000) GS:ffff888268efc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555747cb4a8 CR3: 000000014263c000 CR4: 00000000003506f0 Call Trace: hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0x8b/0xb0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2061 [inline] RIP: 0010:vprintk_emit+0x567/0x6d0 kernel/printk/printk.c:2449 Code: 00 4d 85 ed 0f 85 19 01 00 00 e8 74 80 20 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 d2 7b 20 00 48 85 ed 0f 85 25 01 00 00 54 80 20 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00 RSP: 0018:ffffc900163af9e8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000017 RCX: ffffffff815d802c RDX: ffff8881130b3a00 RSI: ffffffff815d8036 RDI: 0000000000000007 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff92002c75f3f R13: 0000000000000200 R14: ffff888102685700 R15: ffffc900163afab0 _printk+0xc7/0x100 kernel/printk/printk.c:2475 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+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5b6/0x6c0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245