INFO: task kworker/0:2:2803 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:2 state:D
stack:21400 pid:2803 tgid:2803 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1138/0x47e0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
rwsem_down_write_slowpath+0x4c2/0x12c0 kernel/locking/rwsem.c:1215
__down_write_common kernel/locking/rwsem.c:1347 [inline]
__down_write kernel/locking/rwsem.c:1356 [inline]
down_write+0x1c7/0x1f0 kernel/locking/rwsem.c:1626
kernfs_add_one+0x38/0x850 fs/kernfs/dir.c:826
kernfs_create_link+0x1a9/0x240 fs/kernfs/symlink.c:48
sysfs_do_create_link_sd+0x90/0x140 fs/sysfs/symlink.c:44
sysfs_do_create_link fs/sysfs/symlink.c:80 [inline]
sysfs_create_link+0x61/0xc0 fs/sysfs/symlink.c:92
driver_sysfs_add+0x91/0x2d0 drivers/base/dd.c:490
really_probe+0x146/0xa60 drivers/base/dd.c:697
__driver_probe_device+0x22e/0x480 drivers/base/dd.c:871
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:901
__device_attach_driver+0x1df/0x340 drivers/base/dd.c:1029
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1101
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1156
bus_probe_device+0x64/0x160 drivers/base/bus.c:613
device_add+0x1210/0x1950 drivers/base/core.c:3706
usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268
usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250
usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:631 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:709
__driver_probe_device+0x22e/0x480 drivers/base/dd.c:871
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:901
__device_attach_driver+0x1df/0x340 drivers/base/dd.c:1029
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1101
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1156
bus_probe_device+0x64/0x160 drivers/base/bus.c:613
device_add+0x1210/0x1950 drivers/base/core.c:3706
usb_new_device.cold+0x685/0x115c 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+0x314d/0x4af0 drivers/usb/core/hub.c:5953
process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314
process_scheduled_works kernel/workqueue.c:3397 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x69a/0xc80 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:
5 locks held by kworker/1:1/28:
#0: ffff888102abcd40 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
#1: ffffc900001e7d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
#2: ffff88810cb531d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#2: ffff88810cb531d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
#3: ffff88811ef3b1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#3: ffff88811ef3b1d8 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2336
#4: ffff888100e87980 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_find_and_get_ns+0x2f/0x70 fs/kernfs/dir.c:969
1 lock held by khungtaskd/30:
#0: ffffffff896de960 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff896de960 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff896de960 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:2/36:
#0: ffff8881000ac940 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
#1: ffffc90000267d18 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
2 locks held by kworker/u8:7/330:
#0: ffff8881000ac940 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
#1: ffffc90001d8fd18 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
8 locks held by kworker/0:2/2803:
1 lock held by udevd/2858:
#0: ffff888100e87980 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_dop_revalidate+0xa5/0x7e0 fs/kernfs/dir.c:1218
2 locks held by getty/2922:
#0: ffff8881134900a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1:
ffffc900000452e8
(
&ldata->atomic_read_lock
){+.+.}-{4:4}
, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211
3 locks held by udevd/5240:
#0:
ffff888115a2b110
(
&evdev->mutex
){+.+.}-{4:4}
, at: evdev_close_device drivers/input/evdev.c:402 [inline]
, at: evdev_release+0x29e/0x420 drivers/input/evdev.c:447
#1: ffff88811eef92b8
(
&dev->mutex
#2){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#2){+.+.}-{4:4}, at: input_close_device+0x46/0x290 drivers/input/input.c:646
#2:
ffffffff896ea4a8
(
rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
3 locks held by kworker/0:4/5241:
#0: ffff88810006b140
(
(wq_completion)events
){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
#1: ffffc9000325fd18 ((fqdir_free_work).work
){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
#2: ffffffff896ea378
(rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6d0 kernel/rcu/tree.c:3828
2 locks held by kworker/1:5/5335:
7 locks held by kworker/1:0/8213:
#0: ffff888102abcd40 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
#1: ffffc90013927d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
#2: ffff88810cb3b1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#2: ffff88810cb3b1d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
#3: ffff888115fa61d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#3: ffff888115fa61d8 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2336
#4: ffff88811e7d11a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#4: ffff88811e7d11a0 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1174 [inline]
#4: ffff88811e7d11a0 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1372
#5: ffff888112785a58 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#5: ffff888112785a58 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1174 [inline]
#5: ffff888112785a58 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1372
#6: ffff88811eef92b8 (&dev->mutex#2){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#6: ffff88811eef92b8 (&dev->mutex#2){+.+.}-{4:4}, at: input_disconnect_device drivers/input/input.c:703 [inline]
#6: ffff88811eef92b8 (&dev->mutex#2){+.+.}-{4:4}, at: __input_unregister_device+0x24/0x470 drivers/input/input.c:2202
3 locks held by kworker/u8:0/9205:
#0: ffff888100e98940 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
#1: ffffc90001fafd18 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
#2: ffffffff8aadc468 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:673
2 locks held by kworker/1:6/11353:
2 locks held by kworker/1:7/11605:
2 locks held by syz-executor/11930:
#0: ffffffff8aadc468 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1:
ffffffff8aaf4fe0 (rtnl_mutex
){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
){+.+.}-{4:4}, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:248
2 locks held by syz-executor/11940:
#0: ffffffff8aadc468
(
pernet_ops_rwsem){++++}-{4:4}
, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1: ffffffff8aaf4fe0 (rtnl_mutex
){+.+.}-{4:4}
, at: fib_net_exit_batch+0x15/0x130 net/ipv4/fib_frontend.c:1676
3 locks held by syz-executor/11951:
#0: ffffffff8aadc468 (
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1: ffffffff8aaf4fe0
(
rtnl_mutex
){+.+.}-{4:4}, at: default_device_exit_batch+0x90/0xc10 net/core/dev.c:13062
#2: ffffffff896ea4a8 (rcu_state.exp_mutex
){+.+.}-{4:4}
, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
2 locks held by syz-executor/11953:
#0:
ffffffff8aadc468 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1:
ffffffff8aaf4fe0
(rtnl_mutex){+.+.}-{4:4}
, at: fib_net_exit_batch+0x15/0x130 net/ipv4/fib_frontend.c:1676
1 lock held by syz-executor/11956:
#0: ffffffff8aadc468
(
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
2 locks held by syz-executor/11981:
#0: ffffffff8aadc468 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1: ffffffff8aaf4fe0 (
rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:248
1 lock held by syz-executor/11991:
#0: ffffffff8aadc468 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
2 locks held by syz-executor/12001:
#0:
ffffffff8aadc468 (pernet_ops_rwsem){++++}-{4:4}
, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1: ffffffff8aaf4fe0
(
rtnl_mutex
){+.+.}-{4:4}
, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:248
2 locks held by syz-executor/12004:
#0: ffffffff8aadc468 (
pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1: ffffffff8aaf4fe0 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
#1: ffffffff8aaf4fe0 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:248
2 locks held by syz-executor/12012:
#0:
ffffffff8aadc468 (pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1:
ffffffff8aaf4fe0 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
ffffffff8aaf4fe0 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:248
2 locks held by syz-executor/12031:
#0:
ffffffff8aadc468 (pernet_ops_rwsem
){++++}-{4:4}
, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1: ffffffff8aaf4fe0
(rtnl_mutex){+.+.}-{4:4}
, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline]
, at: register_netdev+0x18/0x50 net/core/dev.c:11536
1 lock held by syz-executor/12041:
#0:
ffffffff8aaf4fe0
(rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978
1 lock held by syz-executor/12049:
#0: ffffffff8aaf4fe0
(
rtnl_mutex
){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
){+.+.}-{4:4}, at: rtnl_newlink+0x8bb/0x2210 net/core/rtnetlink.c:4109
1 lock held by syz-executor/12051:
#0: ffffffff8aaf4fe0
(rtnl_mutex){+.+.}-{4:4}
, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
, at: rtnl_newlink+0x8bb/0x2210 net/core/rtnetlink.c:4109
1 lock held by syz-executor/12075:
#0:
ffffffff8aaf4fe0 (
rtnl_mutex
){+.+.}-{4:4}
, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 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+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5335 Comm: kworker/1:5 Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events legacy_dvb_usb_read_remote_control
RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:408
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 96 fa 4d 04 e8 61 ab f5 fe eb a0 e8 ea ab f5
RSP: 0018:ffffc90003c4f6b8 EFLAGS: 00000006
RAX: 0000000000000000 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: ffffffff8322f515 RDI: ffffffff941da800
RBP: ffffffff941da7c0 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff941da810 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8882687a5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcafb525e9c CR3: 00000001175b6000 CR4: 00000000003506f0
Call Trace:
serial_out drivers/tty/serial/8250/8250.h:133 [inline]
serial8250_clear_IER+0xa7/0xd0 drivers/tty/serial/8250/8250_port.c:716
serial8250_console_write+0x252/0x1900 drivers/tty/serial/8250/8250_port.c:3325
console_emit_next_record kernel/printk/printk.c:3183 [inline]
console_flush_one_record+0x790/0xe50 kernel/printk/printk.c:3269
console_flush_all kernel/printk/printk.c:3343 [inline]
__console_flush_and_unlock kernel/printk/printk.c:3373 [inline]
console_unlock+0x103/0x260 kernel/printk/printk.c:3413
vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479
_printk+0xcf/0x110 kernel/printk/printk.c:2504
legacy_dvb_usb_read_remote_control.cold+0x11/0x16 drivers/media/usb/dvb-usb/dvb-usb-remote.c:124
process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314
process_scheduled_works kernel/workqueue.c:3397 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245