INFO: task kworker/0:4:5670 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:4 state:D stack:22176 pid:5670 tgid:5670 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5504 [inline]
__schedule+0x172b/0x5550 kernel/sched/core.c:7228
__schedule_loop kernel/sched/core.c:7307 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7322
schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75
wait_for_completion+0x2c[ 355.390981][ T38] do_wait_for_common kernel/sched/completion.c:100 [inline]
wait_for_completion+0x2c[ 355.390981][ T38] __wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_completion+0x2c[ 355.390981][ T38] wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2c[ 355.390981][ T38] wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153
i2c_del_adapter+0x27f/0x430 drivers/i2c/i2c-core-base.c:1840
dvb_usbv2_probe+0x4c0/0x3c20 drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:994
usb_probe_interface+0x659/0xc70 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x267/0xaf0 drivers/base/dd.c:706
__driver_probe_device+0x1e2/0x350 drivers/base/dd.c:868
driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
__device_attach_driver+0x270/0x410 drivers/base/dd.c:1026
bus_for_each_drv+0x25b/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c8/0x450 drivers/base/dd.c:1098
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x12d/0x220 drivers/base/bus.c:620
device_add+0x7ec/0xb90 drivers/base/core.c:3772
usb_set_configuration+0x1a87/0x2110 drivers/usb/core/message.c:2268
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:706
__driver_probe_device+0x1e2/0x350 drivers/base/dd.c:868
driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
__device_attach_driver+0x270/0x410 drivers/base/dd.c:1026
bus_for_each_drv+0x25b/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c8/0x450 drivers/base/dd.c:1098
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x12d/0x220 drivers/base/bus.c:620
device_add+0x7ec/0xb90 drivers/base/core.c:3772
usb_new_device+0x9f8/0x16e0 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+0x2a49/0x4f60 drivers/usb/core/hub.c:5953
process_one_work+0x98b/0x1630 kernel/workqueue.c:3326
process_scheduled_works kernel/workqueue.c:3409 [inline]
worker_thread+0xb49/0x1140 kernel/workqueue.c:3490
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:
6 locks held by kworker/u8:0/12:
#0: ffff88801ae94138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3301
#1: ffffc90000117c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3302
#2: ffff8880610be310 (&devlink->lock_key#7){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xbd0 drivers/net/netdevsim/dev.c:909
#3: ffffffff8e3cb2a0 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163
#4: ffff88805db74848 (_T->lock){....}-{2:2}, at: rt_mutex_slowunlock+0xbf/0x8b0 kernel/locking/rtmutex.c:1430
#5: ffffffff8e3cb2a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#5: ffffffff8e3cb2a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#5: ffffffff8e3cb2a0 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#5: ffffffff8e3cb2a0 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
1 lock held by khungtaskd/38:
#0: ffffffff8e3cb2a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e3cb2a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8e3cb2a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777
2 locks held by kworker/u8:9/1058:
#0: ffff888033233138 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3301
#1: ffffc90005dafc40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3302
2 locks held by getty/5360:
#0: ffff8880366560a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x465/0x1490 drivers/tty/n_tty.c:2211
5 locks held by kworker/0:4/5670:
#0: ffff8880226d6138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3301
#1: ffffc90004607c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3302
#2: ffff8880227f4210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#2: ffff8880227f4210 (&dev->mutex){....}-{4:4}, at: hub_event+0x17c/0x4f60 drivers/usb/core/hub.c:5899
#3: ffff8880397d2210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#3: ffff8880397d2210 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1073
#4: ffff8880378011d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline]
#4: ffff8880378011d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1073
2 locks held by kworker/u8:12/5826:
#0: ffff88801ae94138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3301
#1: ffffc900045c7c40 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3302
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 1058 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: bat_events batadv_dat_purge
RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:146 [inline]
RIP: 0010:check_preemption_disabled+0x2a/0xe0 lib/smp_processor_id.c:19
Code: 55 41 57 41 56 53 65 8b 05 e7 3d 7d 07 65 8b 0d dc 3d 7d 07 f7 c1 ff ff ff 7f 74 0c 5b 41 5e 41 5f 5d c3 cc cc cc cc cc 9c 59 c1 00 02 00 00 74 ea 65 4c 8b 3d 8e 3d 7d 07 41 f6 47 2f 04 74
RSP: 0018:ffffc90005dafa68 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000000046
RDX: 0000000000000000 RSI: ffffffff8b6b3280 RDI: ffffffff8bcc4d80
RBP: 1ffff1100508055e R08: ffffffff8fcf38f7 R09: 1ffffffff1f9e71e
R10: dffffc0000000000 R11: fffffbfff1f9e71f R12: 0000000000000282
R13: dffffc0000000000 R14: ffff888028402af4 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125a6b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055e9eae7da90 CR3: 0000000034e80000 CR4: 00000000003526f0
Call Trace:
__local_bh_enable_ip+0xe3/0x2b0 kernel/softirq.c:283
local_bh_enable include/linux/bottom_half.h:33 [inline]
spin_unlock_bh include/linux/spinlock_rt.h:116 [inline]
__batadv_dat_purge+0x344/0x400 net/batman-adv/distributed-arp-table.c:186
batadv_dat_purge+0x20/0x70 net/batman-adv/distributed-arp-table.c:205
process_one_work+0x98b/0x1630 kernel/workqueue.c:3326
process_scheduled_works kernel/workqueue.c:3409 [inline]
worker_thread+0xb49/0x1140 kernel/workqueue.c:3490
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