INFO: task kworker/0:6:5968 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:6 state:D stack:20704 pid:5968 tgid:5968 ppid:2 task_flags:0x4288060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5354 [inline] __schedule+0x165c/0x5520 kernel/sched/core.c:6966 __schedule_loop kernel/sched/core.c:7049 [inline] schedule+0x164/0x360 kernel/sched/core.c:7064 schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153 i2c_del_adapter+0x5c0/0x790 drivers/i2c/i2c-core-base.c:1814 release_nodes drivers/base/devres.c:546 [inline] devres_release_group+0x26f/0x370 drivers/base/devres.c:739 hid_device_remove+0x250/0x370 drivers/hid/hid-core.c:2836 device_remove drivers/base/dd.c:631 [inline] __device_release_driver drivers/base/dd.c:1344 [inline] device_release_driver_internal+0x46f/0x870 drivers/base/dd.c:1367 bus_remove_device+0x455/0x570 drivers/base/bus.c:657 device_del+0x527/0x8f0 drivers/base/core.c:3881 hid_remove_device drivers/hid/hid-core.c:3017 [inline] hid_destroy_device+0x6b/0x1b0 drivers/hid/hid-core.c:3039 usbhid_disconnect+0x9f/0xc0 drivers/hid/usbhid/hid-core.c:1477 usb_unbind_interface+0x26e/0x910 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:633 [inline] __device_release_driver drivers/base/dd.c:1344 [inline] device_release_driver_internal+0x4d9/0x870 drivers/base/dd.c:1367 bus_remove_device+0x455/0x570 drivers/base/bus.c:657 device_del+0x527/0x8f0 drivers/base/core.c:3881 usb_disable_device+0x3d4/0x8d0 drivers/usb/core/message.c:1478 usb_disconnect+0x32f/0x990 drivers/usb/core/hub.c:2345 hub_port_connect drivers/usb/core/hub.c:5407 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x1cc9/0x4f30 drivers/usb/core/hub.c:5953 process_one_work kernel/workqueue.c:3278 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3361 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3442 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8eb5d0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8eb5d0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8eb5d0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5599: #0: ffff8880327da0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:3/5841: #0: ffff8880222b6940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3253 [inline] #0: ffff8880222b6940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3361 #1: ffffc900039b7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3254 [inline] #1: ffffc900039b7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3361 #2: ffff88802a8101d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:995 [inline] #2: ffff88802a8101d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 6 locks held by kworker/0:6/5968: #0: ffff8880222b6940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3253 [inline] #0: ffff8880222b6940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3361 #1: ffffc90004a7fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3254 [inline] #1: ffffc90004a7fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3361 #2: ffff88802a89f1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:995 [inline] #2: ffff88802a89f1d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff888037dee1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:995 [inline] #3: ffff888037dee1d8 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0xf8/0x990 drivers/usb/core/hub.c:2336 #4: ffff88802a8c61a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:995 [inline] #4: ffff88802a8c61a0 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1166 [inline] #4: ffff88802a8c61a0 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x870 drivers/base/dd.c:1364 #5: ffff888031c39a58 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:995 [inline] #5: ffff888031c39a58 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1166 [inline] #5: ffff888031c39a58 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x870 drivers/base/dd.c:1364 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 8702 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:dequeue_entity kernel/sched/fair.c:5626 [inline] RIP: 0010:dequeue_entities+0x752/0x3820 kernel/sched/fair.c:7281 Code: 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 28 09 00 00 41 c6 06 01 48 8b 5c 24 60 4c 8b 74 24 20 48 8b 84 24 a8 00 00 00 80 3c 28 00 <74> 08 48 89 df e8 e4 6e 97 00 4c 3b 3b 4c 8b 6c 24 08 74 0b 4c 89 RSP: 0018:ffffc90005cef838 EFLAGS: 00000046 RAX: 1ffff110170e75e3 RBX: ffff8880b873af18 RCX: 1ffff110067aaf10 RDX: 0000000000300000 RSI: ffffffff8e4d941a RDI: ffff8880b873aee0 RBP: dffffc0000000000 R08: ffffffff905495f7 R09: 1ffffffff20a92be R10: dffffc0000000000 R11: fffffbfff20a92bf R12: 000000000003bbec R13: 1ffff110067aaf0f R14: ffff888033d578b8 R15: ffff888033d57800 FS: 000055557cab5500(0000) GS:ffff8881250e7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b34d1fff8 CR3: 0000000078f6a000 CR4: 00000000003526f0 Call Trace: dequeue_task_fair+0x200/0x660 kernel/sched/fair.c:7377 block_task kernel/sched/core.c:2223 [inline] try_to_block_task kernel/sched/core.c:6589 [inline] __schedule+0x6d1/0x5520 kernel/sched/core.c:6901 __schedule_loop kernel/sched/core.c:7049 [inline] schedule+0x164/0x360 kernel/sched/core.c:7064 do_nanosleep+0x1c2/0x620 kernel/time/hrtimer.c:2292 hrtimer_nanosleep+0x18f/0x3a0 kernel/time/hrtimer.c:2338 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1391 [inline] __se_sys_clock_nanosleep+0x35b/0x3b0 kernel/time/posix-timers.c:1368 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8aec95cfce Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007ffd56e1e708 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 000055557cab5500 RCX: 00007f8aec95cfce RDX: 00007ffd56e1e760 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffd56e1e7cc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000001388 R13: 00000000000927c0 R14: 00000000000785e9 R15: 00007ffd56e1e820