INFO: task kworker/0:4:14213 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:4     state:D
 stack:22304 pid:14213 tgid:14213 ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events request_firmware_work_func

Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0xeb1/0x4220 kernel/sched/core.c:6911
 __schedule_loop kernel/sched/core.c:6993 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7008
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
 __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]
 ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1161 [inline]
 ath9k_hif_usb_firmware_cb+0x3b2/0x530 drivers/net/wireless/ath/ath9k/hif_usb.c:1294
 request_firmware_work_func+0x13c/0x250 drivers/base/firmware_loader/main.c:1152
 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
 process_scheduled_works kernel/workqueue.c:3359 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff896de6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff896de6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff896de6e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
5 locks held by kworker/0:3/2819:
1 lock held by klogd/2849:
 #0: ffff8881f5639620 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline]
 #0: ffff8881f5639620 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1615 [inline]
 #0: ffff8881f5639620 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1946 [inline]
 #0: ffff8881f5639620 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x2ca/0x4220 kernel/sched/core.c:6814
2 locks held by getty/2923:
 #0: ffff88811607b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
4 locks held by udevd/5212:
 #0: ffff888144a6a0a0 (&p->lock){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
 #1: ffff888135408488 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
 #2: ffff888104ace1e8 (kn->active#21){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff888104ace1e8 (kn->active#21){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
 #3: ffff88814511b198 (&dev->mutex
){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:900 [inline]
){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
3 locks held by kworker/1:2/5223:
 #0: ffff88810006b148 ((wq_completion)events
){+.+.}-{0:0}
, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc9000343fd18 ((work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffff88810ab59198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #2: ffff88810ab59198 (&dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1161 [inline]
 #2: ffff88810ab59198 (&dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_cb+0x3b2/0x530 drivers/net/wireless/ath/ath9k/hif_usb.c:1294
6 locks held by kworker/1:4/5237:
 #0: 
ffff888103e91148
 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc90003507d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffff88810ab71198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #2: ffff88810ab71198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
 #3: ffff8881176a8198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #3: ffff8881176a8198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1008
 #4: ffff88813f42c160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #4: ffff88813f42c160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1008
 #5: ffff888140340e20 (&dev->phy_mutex){+.+.}-{4:4}, at: __asix_mdio_read+0x91/0x240 drivers/net/usb/asix_common.c:487
4 locks held by udevd/5345:
 #0: ffff888119aedd58 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
 #1: ffff8881136a7488 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
 #2: ffff8881333b7788 (kn->active#21){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff8881333b7788 (kn->active#21){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
 #3: ffff8881176a8198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:900 [inline]
 #3: ffff8881176a8198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
5 locks held by kworker/1:0/14150:
3 locks held by kworker/0:4/14213:
 #0: ffff88810006b148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc9000463fd18 ((work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffff88810ab71198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #2: ffff88810ab71198 (&dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1161 [inline]
 #2: ffff88810ab71198 (&dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_cb+0x3b2/0x530 drivers/net/wireless/ath/ath9k/hif_usb.c:1294
6 locks held by kworker/1:3/17120:
 #0: ffff888103e91148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc9001431fd18 (kernfs_notify_work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffffffff899377d8 (kernfs_notify_lock){....}-{3:3}, at: spin_lock_irq include/linux/spinlock.h:371 [inline]
 #2: ffffffff899377d8 (kernfs_notify_lock){....}-{3:3}, at: kernfs_notify_workfn+0x7f/0x5f0 fs/kernfs/file.c:919
 #3: ffff888101298188 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_notify_workfn+0xff/0x5f0 fs/kernfs/file.c:933
 #4: ffffffff896de6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #4: ffffffff896de6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #4: ffffffff896de6e0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
 #4: ffffffff896de6e0 (rcu_read_lock){....}-{1:3}, at: kernfs_root+0x23/0x2a0 fs/kernfs/kernfs-internal.h:75
 #5: ffff8881042a4508 (&p->pi_lock){-.-.}-{2:2}, at: class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:570 [inline]
 #5: ffff8881042a4508 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0xb4/0x1660 kernel/sched/core.c:4130
3 locks held by syz.2.3827/18889:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 __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+0xd25/0x1050 kernel/hung_task.c:515
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 5e b1 01 e9 53 e8 02 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 33 47 1d 00 fb f4 <c3> cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff89407e10 EFLAGS: 00000246
RAX: 0000000002c3cbbd RBX: ffffffff8942ea40 RCX: ffffffff876938d5
RDX: 0000000000000000 RSI: ffffffff89022879 RDI: ffffffff87afc6a0
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed103eac6725
R10: ffff8881f563392b R11: 0000000000000000 R12: fffffbfff1285d48
R13: 0000000000000000 R14: ffffffff8aeffcd0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8882686ce000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c391a8f CR3: 000000013cb2c000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:73 [inline]
 default_idle+0x9/0x10 arch/x86/kernel/process.c:767
 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x43a/0x550 kernel/sched/idle.c:341
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:439
 rest_init+0x251/0x260 init/main.c:760
 start_kernel+0x47a/0x480 init/main.c:1210
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x148
 </TASK>