INFO: task kworker/0:3:5219 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:3 state:D stack:21816 pid:5219 tgid:5219 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events request_firmware_work_func 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 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820 device_lock include/linux/device.h:1040 [inline] ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1161 [inline] ath9k_hif_usb_firmware_cb+0x3b5/0x530 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+0xa0e/0x1980 kernel/workqueue.c:3302 process_scheduled_works kernel/workqueue.c:3385 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466 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: 1 lock held by khungtaskd/30: #0: ffffffff896de8e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by getty/2918: #0: ffff8881082fc0a0 ( &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 kworker/0:3/5219: #0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0} , at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3277 #1: ffffc90003d5fd18 ((work_completion)(&fw_work->work)){+.+.}-{0:0} , at: process_one_work+0x973/0x1980 kernel/workqueue.c:3278 #2: ffff88810c7f41d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline] ffff88810c7f41d8 (&dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1161 [inline] ffff88810c7f41d8 (&dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_cb+0x3b5/0x530 drivers/net/wireless/ath/ath9k/hif_usb.c:1294 4 locks held by udevd/5231: #0: ffff888115252bd8 ( &p->lock ){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183 #1: ffff88810bf60080 ( &of->mutex #2 ){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff88812288e5a8 ( kn->active #20 ){++++}-{0:0} , at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] , at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff88813b6331d8 ( &dev->mutex ){....}-{4:4} , at: device_lock_interruptible include/linux/device.h:1045 [inline] , at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 6 locks held by kworker/1:5/5298: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 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: 23 Comm: kworker/1:0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: events legacy_dvb_usb_read_remote_control RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:146 [inline] RIP: 0010:lock_acquire kernel/locking/lockdep.c:5869 [inline] RIP: 0010:lock_acquire+0x17d/0x370 kernel/locking/lockdep.c:5825 Code: 00 00 85 d2 0f 85 98 00 00 00 9c 8f 04 24 fa 48 c7 c7 29 21 16 89 e8 a2 a7 de 05 45 89 e8 44 89 e1 89 da 65 ff 05 ab be 68 0b <4c> 8b 14 24 44 89 f6 48 89 ef 41 81 e2 00 02 00 00 4c 89 14 24 4d RSP: 0018:ffffc900001a8938 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffffffff89162129 RDI: ffffffff87b08de0 RBP: ffffffff896de8e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000200 R11: 00000000000098d8 R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8882687a5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000004140 CR3: 0000000123b56000 CR4: 00000000003506f0 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] class_rcu_constructor include/linux/rcupdate.h:1181 [inline] unwind_next_frame+0xd1/0x2090 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 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x43/0x70 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] slab_free mm/slub.c:6250 [inline] kmem_cache_free+0x108/0x660 mm/slub.c:6377 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2869 handle_softirqs+0x1dd/0x9e0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x160/0x210 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline] RIP: 0010:vprintk_emit+0x553/0x6b0 kernel/printk/printk.c:2478 Code: 00 4d 85 ed 0f 85 1b 01 00 00 e8 f8 d7 20 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 c6 d2 20 00 48 85 ed 0f 85 27 01 00 00 d8 d7 20 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00 RSP: 0018:ffffc9000018fa20 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 000000000000003a RCX: ffffffff8191f77a RDX: ffff888102688000 RSI: ffffffff8191f784 RDI: ffff888102688000 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff92000031f46 R13: 0000000000000200 R14: ffff8881026e9dc0 R15: ffffc9000018fae8 _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:3302 process_scheduled_works kernel/workqueue.c:3385 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466 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