INFO: task kworker/0:3:5877 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/0:3 state:D stack:21032 pid:5877 tgid:5877 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x15dd/0x52d0 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0x164/0x360 kernel/sched/core.c:7008 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:721 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:863 driver_probe_device+0x4f/0x240 drivers/base/dd.c:893 __device_attach_driver+0x279/0x430 drivers/base/dd.c:1021 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500 __device_attach+0x2c5/0x450 drivers/base/dd.c:1093 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1148 bus_probe_device+0x12a/0x220 drivers/base/bus.c:613 device_add+0x7b6/0xb70 drivers/base/core.c:3691 usb_set_configuration+0x1a87/0x2110 drivers/usb/core/message.c:2266 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:721 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:863 driver_probe_device+0x4f/0x240 drivers/base/dd.c:893 __device_attach_driver+0x279/0x430 drivers/base/dd.c:1021 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500 __device_attach+0x2c5/0x450 drivers/base/dd.c:1093 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1148 bus_probe_device+0x12a/0x220 drivers/base/bus.c:613 device_add+0x7b6/0xb70 drivers/base/core.c:3691 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 kernel/workqueue.c:3276 [inline] process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440 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 INFO: task syz.7.1130:9933 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.1130 state:D stack:28160 pid:9933 tgid:9919 ppid:8032 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x15dd/0x52d0 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0x164/0x360 kernel/sched/core.c:7008 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 device_lock include/linux/device.h:949 [inline] usbdev_open+0x182/0x770 drivers/usb/core/devio.c:1054 chrdev_open+0x4cd/0x5e0 fs/char_dev.c:411 do_dentry_open+0x785/0x14e0 fs/open.c:949 vfs_open+0x3b/0x340 fs/open.c:1081 do_open fs/namei.c:4671 [inline] path_openat+0x2e08/0x3860 fs/namei.c:4830 do_file_open+0x23e/0x4a0 fs/namei.c:4859 do_sys_openat2+0x113/0x200 fs/open.c:1366 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1383 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f313b15cfce RSP: 002b:00007f313c0f9b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f313c0fa6c0 RCX: 00007f313b15cfce RDX: 0000000000109301 RSI: 00007f313c0f9c00 RDI: ffffffffffffff9c RBP: 00007f313c0f9c00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd R13: 00007f313b416128 R14: 00007f313b416090 R15: 00007f313b53fa48 Showing all locks held in the system: 1 lock held by ksoftirqd/0/15: 1 lock held by khungtaskd/30: #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5578: #0: ffff8880367530a0 (&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 5 locks held by kworker/0:3/5877: #0: ffff888021a89d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #0: ffff888021a89d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359 #1: ffffc90004277c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc90004277c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 #2: ffff888029d9a1e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #2: ffff888029d9a1e0 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff88803304d1e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #3: ffff88803304d1e0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1068 #4: ffff8880274971a8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #4: ffff8880274971a8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1068 5 locks held by kworker/0:5/5923: #0: ffff888021a89d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #0: ffff888021a89d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359 #1: ffffc900045a7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc900045a7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 #2: ffff888029d6e1e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #2: ffff888029d6e1e0 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff888035a8d1e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #3: ffff888035a8d1e0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1068 #4: ffff88805995c1a8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #4: ffff88805995c1a8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1068 6 locks held by kworker/1:7/5939: #0: ffff888021a89d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #0: ffff888021a89d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359 #1: ffffc90004577c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline] #1: ffffc90004577c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359 #2: ffff888029b521e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #2: ffff888029b521e0 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899 #3: ffff888028b4c1e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #3: ffff888028b4c1e0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1068 #4: ffff88806dbb51a8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #4: ffff88806dbb51a8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1068 #5: ffffffff8e5fb9b0 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0xfc/0x2c0 kernel/umh.c:214 1 lock held by syz.7.1130/9933: #0: ffff888029d9a1e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #0: ffff888029d9a1e0 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x182/0x770 drivers/usb/core/devio.c:1054 1 lock held by syz.2.1595/11721: #0: ffff888029d9a1e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #0: ffff888029d9a1e0 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x182/0x770 drivers/usb/core/devio.c:1054 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 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: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+0xfd9/0x1030 kernel/hung_task.c:515 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 02/12/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63 Code: 5e 6c 02 c3 cc cc cc cc 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 e3 a2 1a 00 fb f4 fc e9 02 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffffff8e407dc0 EFLAGS: 00000242 RAX: 0000000000759fad RBX: ffffffff819a913a RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8def8bf9 RDI: ffffffff8c27c900 RBP: ffffffff8e407eb0 R08: ffff8880b863399b R09: 1ffff110170c6733 R10: dffffc0000000000 R11: ffffed10170c6734 R12: 0000000000000000 R13: 1ffffffff1c929d8 R14: 0000000000000000 R15: 1ffffffff1c929d8 FS: 0000000000000000(0000) GS:ffff88812545d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f29d7be92f8 CR3: 000000006c5a4000 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:199 [inline] do_idle+0x36a/0x5f0 kernel/sched/idle.c:352 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451 rest_init+0x2de/0x300 init/main.c:760 start_kernel+0x385/0x3d0 init/main.c:1210 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