INFO: task kworker/1:4:5863 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:4 state:D stack:22344 pid:5863 tgid:5863 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7026
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121
i2c_del_adapter+0x546/0x6f0 drivers/i2c/i2c-core-base.c:1814
dvb_usb_i2c_exit+0x9f/0xf0 drivers/media/usb/dvb-usb/dvb-usb-i2c.c:46
dvb_usb_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:144 [inline]
dvb_usb_device_exit+0x334/0x580 drivers/media/usb/dvb-usb/dvb-usb-init.c:338
cxusb_probe+0x1c9/0x7d0 drivers/media/usb/dvb-usb/cxusb.c:1663
usb_probe_interface+0x303/0xa40 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:581 [inline]
really_probe+0x241/0xa90 drivers/base/dd.c:659
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:801
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:959
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462
__device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
device_add+0x1148/0x1aa0 drivers/base/core.c:3689
usb_set_configuration+0x1187/0x1e20 drivers/usb/core/message.c:2210
usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250
usb_probe_device+0xef/0x3e0 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:581 [inline]
really_probe+0x241/0xa90 drivers/base/dd.c:659
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:801
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:959
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462
__device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
device_add+0x1148/0x1aa0 drivers/base/core.c:3689
usb_new_device+0xd07/0x1a60 drivers/usb/core/hub.c:2694
hub_port_connect drivers/usb/core/hub.c:5566 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
port_event drivers/usb/core/hub.c:5870 [inline]
hub_event+0x2f34/0x4fe0 drivers/usb/core/hub.c:5952
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263
process_scheduled_works kernel/workqueue.c:3346 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 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 rcu_exp_gp_kthr/18:
#0: ffff8880b843a398 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:646 [inline]
#0: ffff8880b843a398 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:631
1 lock held by khungtaskd/31:
#0: ffffffff8e3c4460 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3c4460 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e3c4460 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:2/36:
#0: ffff8880304ad948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238
#1: ffffc90000ac7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239
#2: ffffffff900e6848 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff900e6848 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x120/0x14e0 net/ipv6/addrconf.c:4194
3 locks held by kworker/u8:7/3479:
#0: ffff88814dbf4148 ((wq_completion)udp_tunnel_nic){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238
#1: ffffc9000c2d7d00 ((work_completion)(&utn->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239
#2: ffffffff900e6848 (rtnl_mutex){+.+.}-{4:4}, at: udp_tunnel_nic_device_sync_work+0x27/0xa10 net/ipv4/udp_tunnel_nic.c:736
2 locks held by getty/5575:
#0: ffff888035ced0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
4 locks held by udevd/5810:
#0: ffff888020f2a9e0 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12d0 fs/seq_file.c:182
#1: ffff88807a1a0888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
#2: ffff88807d516a58 (kn->active#19){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff88807d516a58 (kn->active#19){.+.+}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
#3: ffff888054c02198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:919 [inline]
#3: ffff888054c02198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
5 locks held by kworker/1:4/5863:
#0: ffff8881436a2948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238
#1: ffffc90002fb7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239
#2: ffff8880291dc198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
#2: ffff8880291dc198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4fe0 drivers/usb/core/hub.c:5898
#3: ffff888054c02198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
#3: ffff888054c02198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#4: ffff8880551f2160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
#4: ffff8880551f2160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
3 locks held by kworker/0:7/5971:
#0: ffff88813ff11948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238
#1: ffffc90005237d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239
#2: ffff888032f2e240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1b6/0x6da0 drivers/net/netdevsim/fib.c:1490
3 locks held by syz-executor/9069:
#0: ffffffff900e6848 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff900e6848 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff900e6848 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x600/0x2000 net/core/rtnetlink.c:4064
#1: ffff8880764894e8 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_open+0x1fa/0x4d0 drivers/net/wireguard/device.c:50
#2: ffffffff8e3cf9f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:311
1 lock held by syz.0.791/9172:
#0: ffff8880291dc198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
#0: ffff8880291dc198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x1b6/0x8b0 drivers/usb/core/devio.c:1054
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf3f/0x1170 kernel/hung_task.c:495
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 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: 3479 Comm: kworker/u8:7 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: udp_tunnel_nic udp_tunnel_nic_device_sync_work
RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:407
Code: 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1c 66 03 5d 40 44 89 e8 89 da ee <5b> 5d 41 5c 41 5d e9 16 f3 39 06 e8 21 43 fc fc eb a0 e8 aa 43 fc
RSP: 0018:ffffc9000c2d73e0 EFLAGS: 00000002
RAX: 0000000000000033 RBX: 00000000000003f8 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: ffffffff85295455 RDI: ffffffff9add6740
RBP: ffffffff9add6700 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000033 R14: ffffffff9add6700 R15: ffffffff852953f0
FS: 0000000000000000(0000) GS:ffff888124a0a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f36b3bb3ad8 CR3: 0000000065672000 CR4: 00000000003526f0
Call Trace:
serial_port_out include/linux/serial_core.h:811 [inline]
serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3192 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3264 [inline]
serial8250_console_write+0xfbd/0x1890 drivers/tty/serial/8250/8250_port.c:3342
console_emit_next_record kernel/printk/printk.c:3111 [inline]
console_flush_all+0x801/0xc60 kernel/printk/printk.c:3199
__console_flush_and_unlock kernel/printk/printk.c:3258 [inline]
console_unlock+0xd8/0x210 kernel/printk/printk.c:3298
vprintk_emit+0x3d7/0x680 kernel/printk/printk.c:2423
dev_vprintk_emit drivers/base/core.c:4914 [inline]
dev_printk_emit+0xfa/0x140 drivers/base/core.c:4925
__netdev_printk+0x1fb/0x500 net/core/dev.c:12716
netdev_info+0xe4/0x120 net/core/dev.c:12771
nsim_udp_tunnel_set_port+0x250/0x370 drivers/net/netdevsim/udp_tunnels.c:31
udp_tunnel_nic_device_sync_one net/ipv4/udp_tunnel_nic.c:228 [inline]
udp_tunnel_nic_device_sync_by_port net/ipv4/udp_tunnel_nic.c:249 [inline]
__udp_tunnel_nic_device_sync.part.0+0x931/0xe40 net/ipv4/udp_tunnel_nic.c:292
__udp_tunnel_nic_device_sync net/ipv4/udp_tunnel_nic.c:740 [inline]
udp_tunnel_nic_device_sync_work+0xb3/0xa10 net/ipv4/udp_tunnel_nic.c:740
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263
process_scheduled_works kernel/workqueue.c:3346 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245