INFO: task kworker/1:6:5938 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/1:6 state:D stack:20736 pid:5938 tgid:5938 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x14ef/0x4fb0 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 hub_port_connect drivers/usb/core/hub.c:5465 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x21a2/0x4f30 drivers/usb/core/hub.c:5953 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340 worker_thread+0x89f/0xd90 kernel/workqueue.c:3421 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 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: 5 locks held by ksoftirqd/0/15: 1 lock held by khungtaskd/31: #0: ffffffff8e35a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e35a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e35a360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 7 locks held by kworker/1:1/43: #0: ffff88801d6df948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801d6df948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90000b47bc0 ( (work_completion)(&hub->events) ){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] ){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff888028980198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff888028980198 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff88807c98a198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1006 #4: ffff888029fcc160 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:895 [inline] , at: __device_attach+0x88/0x450 drivers/base/dd.c:1006 #5: ffffffff8f21c348 (input_mutex){+.+.}-{4:4}, at: class_mutex_intr_constructor include/linux/mutex.h:255 [inline] #5: ffffffff8f21c348 (input_mutex){+.+.}-{4:4}, at: input_register_device+0xa76/0x1160 drivers/input/input.c:2374 #6: ffff8880311dd2c0 (&dev->mutex#2){+.+.}-{4:4}, at: class_mutex_intr_constructor include/linux/mutex.h:255 [inline] #6: ffff8880311dd2c0 (&dev->mutex#2){+.+.}-{4:4}, at: input_register_handle+0x18d/0x540 drivers/input/input.c:2619 3 locks held by acpid/5180: #0: ffff8880311dc160 (&mousedev->mutex#2){+.+.}-{4:4}, at: mousedev_open_device+0x27/0x150 drivers/input/mousedev.c:423 #1: ffff8880311dd2c0 ( &dev->mutex #2){+.+.}-{4:4}, at: class_mutex_intr_constructor include/linux/mutex.h:255 [inline] #2){+.+.}-{4:4}, at: input_open_device+0x50/0x3b0 drivers/input/input.c:583 #2: ffff888059193ca0 ( &pegasus->pm_mutex ){+.+.}-{4:4} , at: class_mutex_constructor include/linux/mutex.h:253 [inline] , at: __pegasus_open drivers/input/tablet/pegasus_notetaker.c:224 [inline] , at: pegasus_open+0x93/0x240 drivers/input/tablet/pegasus_notetaker.c:251 2 locks held by getty/5582: #0: ffff88814cc7c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 5 locks held by kworker/1:6/5938: #0: ffff88801d6df948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801d6df948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90004b07bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90004b07bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff8881447df198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff8881447df198 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff88802977a518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline] #3: ffff88802977a518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #3: ffff88802977a518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #3: ffff88802977a518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #3: ffff88802977a518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x217a/0x4f30 drivers/usb/core/hub.c:5953 #4: ffff88802958fc68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff88802958fc68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff88802958fc68 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff88802958fc68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21a2/0x4f30 drivers/usb/core/hub.c:5953 4 locks held by udevd/7142: #0: ffff888028ba59e0 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10 fs/seq_file.c:182 #1: ffff888059b62488 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172 #2: ffff88804fa7f2d8 (kn->active#20){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff88804fa7f2d8 (kn->active#20){.+.+}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173 #3: ffff88807c98a198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:900 [inline] #3: ffff88807c98a198 (&dev->mutex){....}-{4:4}, at: product_show+0x26/0xa0 drivers/usb/core/sysfs.c:141 5 locks held by kworker/0:16/7393: #0: ffff88801d6df948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801d6df948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc9000393fbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000393fbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff8881447dc198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff8881447dc198 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff8880297a9518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline] #3: ffff8880297a9518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #3: ffff8880297a9518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #3: ffff8880297a9518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #3: ffff8880297a9518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x217a/0x4f30 drivers/usb/core/hub.c:5953 #4: ffff88802958fc68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline] #4: ffff88802958fc68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] #4: ffff88802958fc68 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline] #4: ffff88802958fc68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21a2/0x4f30 drivers/usb/core/hub.c:5953 2 locks held by syz.3.1667/12769: 5 locks held by syz.5.1668/12771: #0: ffff888011fc2a48 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff888011fc2a48 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline] #0: ffff888011fc2a48 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455 #1: ffffffff8f814850 ((netlink_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain+0x54/0x90 kernel/notifier.c:379 #2: ffffffff8f7a8808 (rtnl_mutex){+.+.}-{4:4}, at: ieee80211_unregister_hw+0x55/0x2c0 net/mac80211/main.c:1673 #3: ffff888033620788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6360 [inline] #3: ffff888033620788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_remove_interfaces+0x132/0x6d0 net/mac80211/iface.c:2407 #4: ffffffff8e360c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #4: ffffffff8e360c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:956 ============================================= 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 01/13/2026 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:161 [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:346 [inline] watchdog+0xf90/0xfe0 kernel/hung_task.c:515 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 8986 Comm: kworker/u8:12 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Workqueue: bat_events batadv_tt_purge RIP: 0010:mark_held_locks kernel/locking/lockdep.c:4322 [inline] RIP: 0010:__trace_hardirqs_on_caller kernel/locking/lockdep.c:4351 [inline] RIP: 0010:lockdep_hardirqs_on_prepare+0x156/0x260 kernel/locking/lockdep.c:4410 Code: bb 10 0b 00 00 00 74 5b 45 31 ff eb 13 49 ff c7 48 63 83 28 0b 00 00 49 83 c6 28 49 39 c7 7d 43 49 83 ff 31 73 2c 41 8b 46 20 00 00 04 00 74 dc 25 00 00 03 00 83 f8 01 ba 07 00 00 00 83 da RSP: 0018:ffffc90002e879b0 EFLAGS: 00000083 RAX: 0000000000040863 RBX: ffff88807db23d00 RCX: ffffffff937e24c8 RDX: 0000000000000006 RSI: ffff88807db24830 RDI: ffff88807db23d00 RBP: fffffffffffffff8 R08: ffffffff8fced977 R09: 1ffffffff1f9db2e R10: dffffc0000000000 R11: fffffbfff1f9db2f R12: ffff88807db24880 R13: dffffc0000000000 R14: ffff88807db24858 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888125a28000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa530fe1198 CR3: 000000007654a000 CR4: 00000000003526f0 Call Trace: trace_hardirqs_on+0x28/0x40 kernel/trace/trace_preemptirq.c:78 __local_bh_enable_ip+0xd0/0x130 kernel/softirq.c:455 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_tt_global_purge net/batman-adv/translation-table.c:2250 [inline] batadv_tt_purge+0x4d1/0x9e0 net/batman-adv/translation-table.c:3510 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340 worker_thread+0x89f/0xd90 kernel/workqueue.c:3421 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 usb 4-1: pegasus_irq - nonzero urb status received: -71 usb 4-1: pegasus_irq - nonzero urb status received: -71 usb 4-1: pegasus_irq - nonzero urb status received: -71 usb 4-1: pegasus_irq - nonzero urb status received: -71 usb 4-1: pegasus_irq - nonzero urb status received: -71 usb 4-1: pegasus_irq - nonzero urb status received: -71 usb 4-1: pegasus_irq - nonzero urb status received: -71