INFO: task kworker/0:5:5957 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/0:5 state:D stack:21352 pid:5957 tgid:5957 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5349 [inline] __schedule+0x1665/0x5590 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7044 [inline] schedule+0x164/0x360 kernel/sched/core.c:7059 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 dvb_usbv2_probe+0x4c3/0x3d40 drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:993 usb_probe_interface+0x668/0xc90 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x267/0xaf0 drivers/base/dd.c:661 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:803 driver_probe_device+0x4f/0x240 drivers/base/dd.c:833 __device_attach_driver+0x279/0x430 drivers/base/dd.c:961 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500 __device_attach+0x2c5/0x450 drivers/base/dd.c:1033 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1088 bus_probe_device+0x12a/0x220 drivers/base/bus.c:574 device_add+0x7b6/0xb70 drivers/base/core.c:3689 usb_set_configuration+0x1a87/0x2110 drivers/usb/core/message.c:2208 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250 usb_probe_device+0x1c4/0x3b0 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x267/0xaf0 drivers/base/dd.c:661 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:803 driver_probe_device+0x4f/0x240 drivers/base/dd.c:833 __device_attach_driver+0x279/0x430 drivers/base/dd.c:961 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500 __device_attach+0x2c5/0x450 drivers/base/dd.c:1033 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1088 bus_probe_device+0x12a/0x220 drivers/base/bus.c:574 device_add+0x7b6/0xb70 drivers/base/core.c:3689 usb_new_device+0xa08/0x16f0 drivers/usb/core/hub.c:2695 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+0x2a1c/0x4f30 drivers/usb/core/hub.c:5953 process_one_work+0x9ab/0x1780 kernel/workqueue.c:3289 process_scheduled_works kernel/workqueue.c:3380 [inline] worker_thread+0xb49/0x1140 kernel/workqueue.c:3461 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 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: ffffffff8eb5f3a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8eb5f3a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8eb5f3a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 1 lock held by klogd/5187: #0: ffff8880b843ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 2 locks held by getty/5587: #0: ffff888037acf0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 4 locks held by udevd/5881: #0: ffff8880423b0540 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10 fs/seq_file.c:183 #1: ffff88807acec088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172 #2: ffff88807780c0f8 (kn->active#24){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff88807780c0f8 (kn->active#24){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173 #3: ffff888028398198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:946 [inline] #3: ffff888028398198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 5 locks held by kworker/0:5/5957: #0: ffff888022a86148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261 #1: ffffc900050ffc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262 #2: ffff88802b545198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline] #2: ffff88802b545198 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff888028398198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline] #3: ffff888028398198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1008 #4: ffff8880359a9160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline] #4: ffff8880359a9160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1008 3 locks held by kworker/u9:3/14656: #0: ffff88803674b148 ((wq_completion)hci3){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261 #1: ffffc900037b7c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262 #2: ffff888087444ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d3/0x400 net/bluetooth/hci_sync.c:331 5 locks held by kworker/u8:11/24116: #0: ffff8880b843ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 #1: ffff8880b8424588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff8880b8426118 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #2: ffff8880b8426118 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085 #3: ffff8880b8424588 (psi_seq){-.-.}-{0:0}, at: psi_task_change+0xd4/0x340 kernel/sched/psi.c:919 #4: ffffffff8eb5f3a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #4: ffffffff8eb5f3a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #4: ffffffff8eb5f3a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1193 [inline] #4: ffffffff8eb5f3a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa5/0x23c0 arch/x86/kernel/unwind_orc.c:495 3 locks held by kworker/u9:1/25241: #0: ffff88802cdf2948 ((wq_completion)hci1){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261 #1: ffffc9000439fc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262 #2: ffff8880249d8ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d3/0x400 net/bluetooth/hci_sync.c:331 1 lock held by syz.5.6565/26478: #0: ffffffff8eb65500 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828 1 lock held by syz.9.6568/26484: #0: ffffffff8eb65500 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828 ============================================= NMI backtrace for cpu 1 CPU: 1 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 02/27/2026 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+0x1002/0x1060 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 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: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/27/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63 Code: ad 90 02 e9 93 ec 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 13 24 2b 00 fb f4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffffff8e807dc0 EFLAGS: 00000246 RAX: 00000000014b90e7 RBX: ffffffff819bd27a RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8e232ba8 RDI: ffffffff8c4a7360 RBP: ffffffff8e807eb0 R08: ffff8880b843399b R09: 1ffff11017086733 R10: dffffc0000000000 R11: ffffed1017086734 R12: ffffffff90544af0 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1d129d8 FS: 0000000000000000(0000) GS:ffff888124dea000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005622f35c6008 CR3: 0000000029a58000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/kernel/process.c:766 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1ba/0x5d0 kernel/sched/idle.c:341 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:439 rest_init+0x2de/0x300 init/main.c:761 start_kernel+0x38a/0x3e0 init/main.c:1212 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147