INFO: task syz.4.2064:13714 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.2064 state:D stack:26392 pid:13714 tgid:13712 ppid:5807 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0xfe4/0x5e10 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:6964
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
device_lock include/linux/device.h:895 [inline]
usbdev_open+0x1b6/0x870 drivers/usb/core/devio.c:1054
chrdev_open+0x234/0x6a0 fs/char_dev.c:414
do_dentry_open+0x73e/0x1570 fs/open.c:962
vfs_open+0x82/0x3f0 fs/open.c:1094
do_open fs/namei.c:4637 [inline]
path_openat+0x21dc/0x3120 fs/namei.c:4796
do_filp_open+0x1f7/0x420 fs/namei.c:4823
do_sys_openat2+0x12e/0x220 fs/open.c:1430
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1447
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2b6895b78e
RSP: 002b:00007f2b69770b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f2b697716c0 RCX: 00007f2b6895b78e
RDX: 000000000000a401 RSI: 00007f2b69770c00 RDI: ffffffffffffff9c
RBP: 00007f2b69770c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007f2b68c16128 R14: 00007f2b68c16090 R15: 00007fff1013fa08
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by getty/5570:
#0: ffff88814df970a0 (&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+0x419/0x1500 drivers/tty/n_tty.c:2211
5 locks held by kworker/1:6/5873:
3 locks held by kworker/0:4/5886:
#0: ffff88813fe51948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232
#1: ffffc900040c7c98 ((work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233
#2: ffffffff8e48dbf0 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_lock_wait+0xc6/0x1a0 kernel/umh.c:246
3 locks held by kworker/0:6/5916:
#0: ffff88813fe51948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232
#1: ffffc900041d7c98 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233
#2: ffffffff903f3168 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
1 lock held by syz.4.2064/13714:
#0: ffff888144b27198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#0: ffff888144b27198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x1b6/0x870 drivers/usb/core/devio.c:1054
1 lock held by syz.5.2144/14150:
#0: ffff888144b27198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#0: ffff888144b27198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x1b6/0x870 drivers/usb/core/devio.c:1054
2 locks held by syz.1.2582/15734:
#0: ffffffff903f3168 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff903f3168 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff903f3168 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink+0x307/0xb40 net/core/rtnetlink.c:3562
#1: ffffffff8e5efab8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
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:161 [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:346 [inline]
watchdog+0xcc3/0xfe0 kernel/hung_task.c:515
kthread+0x3b3/0x730 kernel/kthread.c:463
ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5873 Comm: kworker/1:6 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:__rcu_read_unlock+0xad/0x550 kernel/rcu/tree_plugin.h:441
Code: 88 04 00 00 85 c0 75 51 48 8d bb 84 04 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 <83> c0 03 38 d0 7c 08 84 d2 0f 85 59 01 00 00 8b 83 84 04 00 00 3d
RSP: 0018:ffffc90003fe6890 EFLAGS: 00000202
RAX: 0000000000000004 RBX: ffff88802963a4c0 RCX: ffffc90003fe688c
RDX: 0000000000000000 RSI: ffffffff8dc1f692 RDI: ffff88802963a944
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000051f63 R12: ffffc90003fe6988
R13: ffffc90003fe6938 R14: ffffc90003fe77b8 R15: ffffc90003fe696c
FS: 0000000000000000(0000) GS:ffff8881246d9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f00751e1198 CR3: 000000000e392000 CR4: 00000000003526f0
Call Trace:
rcu_read_unlock include/linux/rcupdate.h:899 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x3c8/0x1ea0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kmalloc_noprof include/linux/slab.h:957 [inline]
dummy_urb_enqueue+0xa3/0x880 drivers/usb/gadget/udc/dummy_hcd.c:1273
usb_hcd_submit_urb+0x26c/0x2150 drivers/usb/core/hcd.c:1546
usb_submit_urb+0x8aa/0x1910 drivers/usb/core/urb.c:587
ath6kl_usb_post_recv_transfers.constprop.0+0x204/0x3d0 drivers/net/wireless/ath/ath6kl/usb.c:450
ath6kl_usb_start_recv_pipes drivers/net/wireless/ath/ath6kl/usb.c:498 [inline]
hif_start drivers/net/wireless/ath/ath6kl/usb.c:703 [inline]
ath6kl_usb_power_on+0x8e/0x160 drivers/net/wireless/ath/ath6kl/usb.c:1062
ath6kl_hif_power_on drivers/net/wireless/ath/ath6kl/hif-ops.h:136 [inline]
ath6kl_core_init+0x173/0x11b0 drivers/net/wireless/ath/ath6kl/core.c:97
ath6kl_usb_probe+0xcd0/0x13e0 drivers/net/wireless/ath/ath6kl/usb.c:1168
usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:583 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:661
__driver_probe_device+0x1de/0x400 drivers/base/dd.c:803
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:833
__device_attach_driver+0x1df/0x340 drivers/base/dd.c:961
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1033
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1088
bus_probe_device+0x64/0x160 drivers/base/bus.c:574
device_add+0x11d9/0x1950 drivers/base/core.c:3689
usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2210
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:583 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:661
__driver_probe_device+0x1de/0x400 drivers/base/dd.c:803
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:833
__device_attach_driver+0x1df/0x340 drivers/base/dd.c:961
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1033
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1088
bus_probe_device+0x64/0x160 drivers/base/bus.c:574
device_add+0x11d9/0x1950 drivers/base/core.c:3689
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+0x9c2/0x1840 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x5da/0xe40 kernel/workqueue.c:3421
kthread+0x3b3/0x730 kernel/kthread.c:463
ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246