INFO: task kworker/0:5:5234 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:5 state:D stack:22680 pid:5234 tgid:5234 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events request_firmware_work_func Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145d/0x4a00 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc69/0x1ca0 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+0x3b1/0x620 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+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Showing all locks held in the system: 6 locks held by kworker/0:0/9: 5 locks held by kworker/0:1/10: #0: ffff888100ed2148 ( (wq_completion)usb_hub_wq ){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232 #1: ffffc900000afca0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233 #2: ffff88810a770198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff88810a770198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1be/0x5420 drivers/usb/core/hub.c:5899 #3: ffff888105b1a198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #3: ffff888105b1a198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4e0 drivers/base/dd.c:1006 #4: ffff888107fbb160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #4: ffff888107fbb160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4e0 drivers/base/dd.c:1006 1 lock held by khungtaskd/30: #0: ffffffff892cd760 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff892cd760 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff892cd760 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 2 locks held by getty/2927: #0: ffff8881073070a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000452f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x1510 drivers/tty/n_tty.c:2211 4 locks held by udevd/5207: #0: ffff888133580e80 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12d0 fs/seq_file.c:182 #1: ffff888115e34088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff88813b7bfc38 (kn->active#18){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff88813b7bfc38 (kn->active#18){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff88811fa23198 (&dev->mutex ){....}-{4:4} , at: device_lock_interruptible include/linux/device.h:900 [inline] , at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 4 locks held by udevd/5210: #0: ffff88810bfdd418 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12d0 fs/seq_file.c:182 #1: ffff888113444888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff88811ec6c0f8 (kn->active#18){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff88811ec6c0f8 (kn->active#18){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff88810ca8a198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:900 [inline] #3: ffff88810ca8a198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 5 locks held by kworker/0:3/5221: 3 locks held by kworker/0:5/5234: #0: ffff888100071948 ((wq_completion)events ){+.+.}-{0:0} , at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232 #1: ffffc9000238fca0 ( (work_completion)(&fw_work->work) ){+.+.}-{0:0} , at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233 #2: ffff88810a3e8198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff88810a3e8198 (&dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1161 [inline] #2: ffff88810a3e8198 (&dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_cb+0x3b1/0x620 drivers/net/wireless/ath/ath9k/hif_usb.c:1294 2 locks held by kworker/1:3/5239: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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] __sys_info lib/sys_info.c:157 [inline] sys_info+0x133/0x180 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xe66/0x1180 kernel/hung_task.c:515 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 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: 11175 Comm: kworker/1:8 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events legacy_dvb_usb_read_remote_control RIP: 0010:match_held_lock+0x0/0xb0 kernel/locking/lockdep.c:5305 Code: 39 35 ce 88 67 48 0f b9 3a 90 31 db eb c4 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <53> 48 89 fb 48 39 77 10 74 55 66 83 7f 22 1f 76 65 48 8b 46 08 48 RSP: 0018:ffffc90013b8f620 EFLAGS: 00000093 RAX: 000000000000000a RBX: ffff8881067c2838 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff93c8af58 RDI: ffff8881067c2838 RBP: ffffffff93c8af58 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: ffff8881067c27e8 R12: ffff8881067c1d40 R13: ffff8881067c27e8 R14: 00000000ffffffff R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff888268cf4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000001000 CR3: 0000000124c46000 CR4: 00000000003506f0 Call Trace: __lock_is_held kernel/locking/lockdep.c:5601 [inline] lock_is_held_type+0xb0/0x150 kernel/locking/lockdep.c:5940 lock_is_held include/linux/lockdep.h:249 [inline] __uart_port_using_nbcon include/linux/serial_core.h:640 [inline] __uart_port_nbcon_acquire include/linux/serial_core.h:674 [inline] uart_port_lock_irqsave include/linux/serial_core.h:718 [inline] serial8250_console_write+0x119b/0x1890 drivers/tty/serial/8250/8250_port.c:3301 console_emit_next_record kernel/printk/printk.c:3129 [inline] console_flush_one_record+0x796/0xc60 kernel/printk/printk.c:3215 console_flush_all kernel/printk/printk.c:3289 [inline] __console_flush_and_unlock kernel/printk/printk.c:3319 [inline] console_unlock+0xef/0x240 kernel/printk/printk.c:3359 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426 _printk+0xc7/0x100 kernel/printk/printk.c:2451 m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline] m920x_rc_query+0x496/0x770 drivers/media/usb/dvb-usb/m920x.c:193 legacy_dvb_usb_read_remote_control+0x10c/0x4f0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246