[v5.15] INFO: task hung in ath9k_hif_usb_firmware_cb (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 91d48252ad4b Linux 5.15.202
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=148d475a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=353ae28c40b35af5
dashboard link: https://syzkaller.appspot.com/bug?extid=d07ffe65d165f9d89153
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/74e75dfcb812/disk-91d48252.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/bfa72aab00f2/vmlinux-91d48252.xz
kernel image: https://storage.googleapis.com/syzbot-assets/47ea72d1c7dc/bzImage-91d48252.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d07ffe...@syzkaller.appspotmail.com

INFO: task kworker/0:9:4283 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:9 state:D stack:24752 pid: 4283 ppid: 2 flags:0x00004000
Workqueue: events request_firmware_work_func
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
device_lock include/linux/device.h:764 [inline]
ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1163 [inline]
ath9k_hif_usb_firmware_cb+0x32c/0x4b0 drivers/net/wireless/ath/ath9k/hif_usb.c:1296
request_firmware_work_func+0xfb/0x1b0 drivers/base/firmware_loader/main.c:1129
process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
INFO: task kworker/0:14:4556 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:14 state:D stack:24336 pid: 4556 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2093
do_wait_for_common+0x2a2/0x450 kernel/sched/completion.c:85
__wait_for_common kernel/sched/completion.c:106 [inline]
wait_for_common kernel/sched/completion.c:117 [inline]
wait_for_completion+0x48/0x60 kernel/sched/completion.c:138
flush_workqueue+0x664/0x13d0 kernel/workqueue.c:2882
hif_detach_htc drivers/net/wireless/ath/ath6kl/usb.c:861 [inline]
ath6kl_usb_power_off+0x34/0x40 drivers/net/wireless/ath/ath6kl/usb.c:1060
ath6kl_hif_power_off drivers/net/wireless/ath/ath6kl/hif-ops.h:143 [inline]
ath6kl_core_init+0xac4/0x1090 drivers/net/wireless/ath/ath6kl/core.c:257
ath6kl_usb_probe+0x1302/0x1410 drivers/net/wireless/ath/ath6kl/usb.c:1160
usb_probe_interface+0x5c5/0xb20 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x284/0xc80 drivers/base/dd.c:595
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:755
driver_probe_device+0x4f/0x420 drivers/base/dd.c:785
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907
bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
__device_attach+0x2a8/0x480 drivers/base/dd.c:979
bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
device_add+0xa00/0xfb0 drivers/base/core.c:3412
usb_set_configuration+0x1991/0x1fd0 drivers/usb/core/message.c:2165
usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238
usb_probe_device+0x139/0x270 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x284/0xc80 drivers/base/dd.c:595
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:755
driver_probe_device+0x4f/0x420 drivers/base/dd.c:785
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907
bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
__device_attach+0x2a8/0x480 drivers/base/dd.c:979
bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
device_add+0xa00/0xfb0 drivers/base/core.c:3412
usb_new_device+0xd65/0x1660 drivers/usb/core/hub.c:2632
hub_port_connect drivers/usb/core/hub.c:5497 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5637 [inline]
port_event drivers/usb/core/hub.c:5799 [inline]
hub_event+0x2e4a/0x55e0 drivers/usb/core/hub.c:5881
process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
INFO: task udevd:4823 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:23120 pid: 4823 ppid: 3561 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
device_lock include/linux/device.h:764 [inline]
uevent_show+0x17a/0x330 drivers/base/core.c:2408
dev_attr_show+0x50/0xb0 drivers/base/core.c:2110
sysfs_kf_seq_show+0x316/0x4c0 fs/sysfs/file.c:61
seq_read_iter+0x49b/0xd50 fs/seq_file.c:230
call_read_iter include/linux/fs.h:2167 [inline]
new_sync_read fs/read_write.c:404 [inline]
vfs_read+0x759/0xd60 fs/read_write.c:485
ksys_read+0x152/0x260 fs/read_write.c:623
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7eff946bb407
RSP: 002b:00007ffdffd02720 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007eff945cd880 RCX: 00007eff946bb407
RDX: 0000000000001000 RSI: 000056054e7ac550 RDI: 0000000000000008
RBP: 00007eff94803ff0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a
R13: 00007eff94803ea0 R14: 0000000000000000 R15: 000056054e7a5c80
</TASK>

Showing all locks held in the system:
4 locks held by kworker/u4:0/9:
1 lock held by khungtaskd/27:
#0: ffffffff8c31eaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:5/3044:
#0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000d8ffd00 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
2 locks held by getty/3949:
#0: ffff88802c5fe098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900026562e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
2 locks held by kworker/0:6/4231:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc900035bfd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
2 locks held by kworker/0:7/4233:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc900035dfd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
2 locks held by kworker/0:8/4274:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000432fd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
3 locks held by kworker/0:9/4283:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000360fd00 ((work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffff888147d52220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#2: ffff888147d52220 (&dev->mutex){....}-{3:3}, at: ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1163 [inline]
#2: ffff888147d52220 (&dev->mutex){....}-{3:3}, at: ath9k_hif_usb_firmware_cb+0x32c/0x4b0 drivers/net/wireless/ath/ath9k/hif_usb.c:1296
3 locks held by kworker/0:13/4555:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc90003807d00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
#2: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845
5 locks held by kworker/0:14/4556:
#0: ffff888018f92538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc90003aa7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffff888147d52220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#2: ffff888147d52220 (&dev->mutex){....}-{3:3}, at: hub_event+0x19f/0x55e0 drivers/usb/core/hub.c:5827
#3: ffff888061608220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#3: ffff888061608220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x480 drivers/base/dd.c:954
#4: ffff8880195b21a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#4: ffff8880195b21a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x480 drivers/base/dd.c:954
3 locks held by kworker/0:16/4558:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffff8880b9027888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4fe/0x7d0 kernel/sched/psi.c:891
#2: ffff888078523240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x26a/0x33e0 drivers/net/netdevsim/fib.c:1480
4 locks held by udevd/4823:
#0: ffff88806920f668 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xad/0xd50 fs/seq_file.c:182
#1: ffff88804b7e0488 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x51/0x3c0 fs/kernfs/file.c:112
#2: ffff888074dc9490 (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0x71/0x3c0 fs/kernfs/file.c:113
#3: ffff888061608220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#3: ffff888061608220 (&dev->mutex){....}-{3:3}, at: uevent_show+0x17a/0x330 drivers/base/core.c:2408
2 locks held by kworker/0:21/7232:
#0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000317fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
2 locks held by syz-executor/9036:
#0: ffff88807d2f80e0 (&type->s_umount_key#74){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
#1: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#1: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
1 lock held by sed/12246:

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
<TASK>
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:729


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