INFO: task kworker/1:4:5897 blocked for more than 143 seconds.
Not tainted 6.14.0-syzkaller-13423-ga8662bcd2ff1 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:4 state:D stack:21096 pid:5897 tgid:5897 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b88/0x5240 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
__mutex_lock_common kernel/locking/mutex.c:678 [inline]
__mutex_lock+0x805/0x10c0 kernel/locking/mutex.c:746
hub_port_connect drivers/usb/core/hub.c:5429 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
port_event drivers/usb/core/hub.c:5831 [inline]
hub_event+0x24cd/0x50f0 drivers/usb/core/hub.c:5913
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
worker_thread+0x870/0xd50 kernel/workqueue.c:3400
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
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: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764
2 locks held by getty/5591:
#0: ffff88814ce260a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000334b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222
5 locks held by kworker/0:3/5840:
#0: ffff888144ed4148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}
, at: process_one_work kernel/workqueue.c:3213 [inline]
, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc9000400fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000400fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
#2: ffff88802a0b0198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#2: ffff88802a0b0198 (&dev->mutex){....}-{4:4}, at: hub_event+0x200/0x50f0 drivers/usb/core/hub.c:5859
#3: ffff888029f4a510 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3220 [inline]
#3: ffff888029f4a510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5428 [inline]
#3: ffff888029f4a510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
#3: ffff888029f4a510 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5831 [inline]
#3: ffff888029f4a510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x2494/0x50f0 drivers/usb/core/hub.c:5913
#4:
ffff88814679d168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5429 [inline]
ffff88814679d168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
ffff88814679d168 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5831 [inline]
ffff88814679d168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x24cd/0x50f0 drivers/usb/core/hub.c:5913
1 lock held by syz-executor/5859:
#0: ffffffff8ed434f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8ed434f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x454/0x830 kernel/rcu/tree_exp.h:998
4 locks held by udevd/5891:
#0: ffff888032e28418 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb4/0xda0 fs/seq_file.c:182
#1: ffff8880348d0c88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x53/0x3b0 fs/kernfs/file.c:154
#2: ffff88807a821e18 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x72/0x3b0 fs/kernfs/file.c:155
#3: ffff88805b635198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#3: ffff88805b635198 (&dev->mutex){....}-{4:4}, at: uevent_show+0x17d/0x340 drivers/base/core.c:2730
5 locks held by kworker/0:4/5892:
#0: ffff888144ed4148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888144ed4148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc900040efc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900040efc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
#2: ffff88802a052198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#2: ffff88802a052198 (&dev->mutex){....}-{4:4}, at: hub_event+0x200/0x50f0 drivers/usb/core/hub.c:5859
#3: ffff88802a055510 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3220 [inline]
#3: ffff88802a055510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5428 [inline]
#3: ffff88802a055510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
#3: ffff88802a055510 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5831 [inline]
#3: ffff88802a055510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x2494/0x50f0 drivers/usb/core/hub.c:5913
#4: ffff88814679d168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5429 [inline]
#4: ffff88814679d168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
#4: ffff88814679d168 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5831 [inline]
#4: ffff88814679d168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x24cd/0x50f0 drivers/usb/core/hub.c:5913
5 locks held by kworker/0:5/5893:
#0: ffff888144ed4148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888144ed4148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc9000434fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000434fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
#2: ffff888146750198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#2: ffff888146750198 (&dev->mutex){....}-{4:4}, at: hub_event+0x200/0x50f0 drivers/usb/core/hub.c:5859
#3: ffff888146753510 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3220 [inline]
#3: ffff888146753510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5428 [inline]
#3: ffff888146753510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
#3: ffff888146753510 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5831 [inline]
#3: ffff888146753510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x2494/0x50f0 drivers/usb/core/hub.c:5913
#4: ffff888146359268 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5429 [inline]
#4: ffff888146359268 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
#4: ffff888146359268 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5831 [inline]
#4: ffff888146359268 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x24cd/0x50f0 drivers/usb/core/hub.c:5913
7 locks held by kworker/0:6/5896:
5 locks held by kworker/1:4/5897:
#0: ffff888144ed4148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888144ed4148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc9000437fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000437fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
#2: ffff888146766198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#2: ffff888146766198 (&dev->mutex){....}-{4:4}, at: hub_event+0x200/0x50f0 drivers/usb/core/hub.c:5859
#3: ffff888146771510 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3220 [inline]
#3: ffff888146771510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5428 [inline]
#3: ffff888146771510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
#3: ffff888146771510 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5831 [inline]
#3: ffff888146771510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x2494/0x50f0 drivers/usb/core/hub.c:5913
#4: ffff888146359268 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5429 [inline]
#4: ffff888146359268 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
#4: ffff888146359268 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5831 [inline]
#4: ffff888146359268 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x24cd/0x50f0 drivers/usb/core/hub.c:5913
2 locks held by kworker/u8:8/8070:
#0: ffff88801d703148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801d703148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc9000bb87c60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000bb87c60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-syzkaller-13423-ga8662bcd2ff1 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:437
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
quatech-serial ttyUSB0: qt2_process_read_urb - unsupported command 113
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 67 Comm: kworker/u8:4 Not tainted 6.14.0-syzkaller-13423-ga8662bcd2ff1 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
RIP: 0010:io_serial_out+0x7e/0xc0 drivers/tty/serial/8250/8250_port.c:416
Code: fc 89 e9 41 d3 e7 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 9c 03 96 fc 44 03 3b 44 89 f0 44 89 fa ee <5b> 41 5c 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c a7
RSP: 0018:ffffc90000006dd0 EFLAGS: 00000006
RAX: 0000000000000000 RBX: ffffffff9aa81bc0 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 00000000000099a0 RDI: 00000000000099a1
RBP: 0000000000000000 R08: ffffffff85977ceb R09: fffff52000000d9c
R10: dffffc0000000000 R11: ffffffff85977ca0 R12: dffffc0000000000
R13: dffffc0000000000 R14: 0000000000000000 R15: 00000000000003f9
FS: 0000000000000000(0000) GS:ffff888124f96000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000030c04ffc CR3: 000000004e0c4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
serial8250_clear_IER drivers/tty/serial/8250/8250_port.c:-1 [inline]
serial8250_console_write+0x52d/0x1e00 drivers/tty/serial/8250/8250_port.c:3421
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x86b/0xec0 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0x151/0x3b0 kernel/printk/printk.c:3325
vprintk_emit+0x761/0xa40 kernel/printk/printk.c:2450
dev_vprintk_emit+0x358/0x420 drivers/base/core.c:4891
dev_printk_emit+0xdf/0x130 drivers/base/core.c:4902
_dev_warn+0x12d/0x180 drivers/base/core.c:4958
qt2_process_read_urb drivers/usb/serial/quatech2.c:529 [inline]
qt2_read_bulk_callback+0xbb3/0x1170 drivers/usb/serial/quatech2.c:574
__usb_hcd_giveback_urb+0x42e/0x6e0 drivers/usb/core/hcd.c:1650
dummy_timer+0x84b/0x4670 drivers/usb/gadget/udc/dummy_hcd.c:1994
__run_hrtimer kernel/time/hrtimer.c:1791 [inline]
__hrtimer_run_queues+0x5a6/0xd40 kernel/time/hrtimer.c:1855
hrtimer_run_softirq+0x19a/0x2c0 kernel/time/hrtimer.c:1872
handle_softirqs+0x2d6/0x9b0 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xfb/0x220 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5250
Code: c9 50 e8 a9 2d 0d 00 48 83 c4 08 4c 89 f7 e8 ad 41 00 00 e9 de 04 00 00 4c 89 f7 e8 90 80 a1 0a e8 cb 88 39 00 fb 48 8b 5d c0 <48> 8d bb 18 16 00 00 48 89 f8 48 c1 e8 03 49 be 00 00 00 00 00 fc
RSP: 0018:ffffc90001587268 EFLAGS: 00000286
RAX: b500f1d8d0028e00 RBX: ffff88801d333c00 RCX: 0000000000000006
RDX: 0000000000000006 RSI: ffffffff8e69c664 RDI: ffffffff8ca1b660
RBP: ffffc900015872b0 R08: ffffffff905fdf77 R09: 1ffffffff20bfbee
R10: dffffc0000000000 R11: fffffbfff20bfbef R12: 1ffff110170c7526
R13: dffffc0000000000 R14: ffff8880b8639b00 R15: ffff8880b863a930
context_switch kernel/sched/core.c:5385 [inline]
__schedule+0x1b90/0x5240 kernel/sched/core.c:6767
preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6947
preempt_schedule+0xe4/0xf0 kernel/sched/core.c:6971
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__local_bh_enable_ip+0x179/0x200 kernel/softirq.c:414
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:910 [inline]
__dev_queue_xmit+0x1780/0x3f60 net/core/dev.c:4663
dev_queue_xmit include/linux/netdevice.h:3350 [inline]
batadv_send_skb_packet+0x433/0x6a0 net/batman-adv/send.c:108
batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:392 [inline]
batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:420 [inline]
batadv_iv_send_outstanding_bat_ogm_packet+0x60b/0x7a0 net/batman-adv/bat_iv_ogm.c:1708
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
worker_thread+0x870/0xd50 kernel/workqueue.c:3400
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245