INFO: task kworker/0:3:5224 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:21688 pid:5224 tgid:5224 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events request_firmware_work_func Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0xeb1/0x41f0 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 __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+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x6c3/0xcb0 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: 5 locks held by kworker/0:1/10: 1 lock held by khungtaskd/30: #0: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 7 locks held by kworker/1:2/1118: #0: ffff888105ab0148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90002c6fd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffff88810b71b198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff88810b71b198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff88811e50e198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] ffff88811e50e198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2336 #4: ffff888119f6c160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #4: ffff888119f6c160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1106 [inline] #4: ffff888119f6c160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xaa/0x600 drivers/base/dd.c:1304 #5: ffffffff8aaf8e68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #5: ffffffff8aaf8e68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x146/0x360 net/core/dev.c:2162 #6: ffffffff896ec1b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 2 locks held by dhcpcd/2892: #0: ffff88811d96e6e0 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0x150/0x990 net/netlink/af_netlink.c:2404 #1: ffffffff8aaf8e68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8aaf8e68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x18f/0x1f0 net/core/rtnetlink.c:6826 2 locks held by getty/2915: #0: ffff8881159820a0 (&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/5199: #0: ffff888134d76540 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183 #1: ffff888112765c88 (&of->mutex #2){+.+.}-{4:4} , at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff8881395e6d28 (kn->active#22){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8881395e6d28 (kn->active#22){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff88811e50e198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:900 [inline] #3: ffff88811e50e198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 6 locks held by kworker/0:2/5215: #0: ffff888105ab0148 ((wq_completion)usb_hub_wq ){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90002d6fd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffff88810bb3b198 ( &dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] ){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff888119288198 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:895 [inline] , at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2336 #4: ffff88811519f160 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:895 [inline] , at: __device_driver_lock drivers/base/dd.c:1106 [inline] , at: device_release_driver_internal+0xaa/0x600 drivers/base/dd.c:1304 #5: ffffffff8a509628 (input_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #5: ffffffff8a509628 (input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x184/0x4d0 drivers/input/input.c:2187 3 locks held by kworker/0:3/5224: #0: ffff88810006b548 ( (wq_completion)events ){+.+.}-{0:0} , at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90002defd18 ( (work_completion)(&fw_work->work) ){+.+.}-{0:0} , at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffff88810bbc3198 ( &dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] &dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1161 [inline] &dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_cb+0x3b2/0x530 drivers/net/wireless/ath/ath9k/hif_usb.c:1294 4 locks held by udevd/5304: #0: ffff88813b977d58 ( &p->lock ){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183 #1: ffff88813965a888 ( &of->mutex #2 ){+.+.}-{4:4} , at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff88813bc7e008 ( kn->active#22){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] kn->active#22){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff888115a7e198 ( &dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:900 [inline] &dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 2 locks held by kworker/0:12/18141: 2 locks held by kworker/0:11/21691: 2 locks held by kworker/0:9/26151: 3 locks held by kworker/1:5/27647: #0: ffff88810006b548 ( (wq_completion)events ){+.+.}-{0:0} , at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90003007d18 ( free_ipc_work ){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffffffff896ec1b8 ( rcu_state.exp_mutex ){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 3 locks held by kworker/u8:3/27892: #0: ffff888101299148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc900028efd18 (net_cleanup_work){+.+.}-{0:0} , at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffffffff8aae0830 ( pernet_ops_rwsem ){++++}-{4:4}, at: cleanup_net+0xb8/0x9e0 net/core/net_namespace.c:675 ============================================= 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: __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:467 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 26151 Comm: kworker/0:9 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events legacy_dvb_usb_read_remote_control RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:37 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:139 [inline] RIP: 0010:wrmsrq arch/x86/include/asm/msr.h:199 [inline] RIP: 0010:native_apic_msr_write arch/x86/include/asm/apic.h:208 [inline] RIP: 0010:native_apic_msr_write+0x28/0x40 arch/x86/include/asm/apic.h:202 Code: 90 90 f3 0f 1e fa 8d 87 30 ff ff ff 83 e0 ef 74 20 89 f8 83 e0 ef 83 f8 20 74 16 c1 ef 04 31 d2 89 f0 8d 8f 00 08 00 00 0f 30 <66> 90 c3 cc cc cc cc c3 cc cc cc cc 89 f6 31 d2 89 cf e9 21 ee 71 RSP: 0018:ffffc90000007ec8 EFLAGS: 00000046 RAX: 0000000000033d94 RBX: ffff8881f5623d40 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 0000000000033d94 RDI: 0000000000000038 RBP: 0000000000033d94 R08: 0000000000000005 R09: 000000000000003f R10: 0000000000000020 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000020 R15: ffff8881f5628140 FS: 0000000000000000(0000) GS:ffff8882686d3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4ff1a69774 CR3: 0000000116d42000 CR4: 00000000003506f0 Call Trace: apic_write arch/x86/include/asm/apic.h:405 [inline] lapic_next_event+0x10/0x20 arch/x86/kernel/apic/apic.c:418 clockevents_program_event+0x26e/0x360 kernel/time/clockevents.c:334 tick_program_event+0xa9/0x140 kernel/time/tick-oneshot.c:48 hrtimer_interrupt+0x3e9/0x8c0 kernel/time/hrtimer.c:1924 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x109/0x490 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x8a/0xb0 arch/x86/kernel/apic/apic.c:1056 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 98 43 20 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 66 3e 20 00 48 85 ed 0f 85 27 01 00 00 78 43 20 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00 RSP: 0018:ffffc90002c9fa28 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 000000000000003a RCX: ffffffff8191779a RDX: ffff8881450c9d00 RSI: ffffffff819177a4 RDI: ffff8881450c9d00 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff92000593f47 R13: 0000000000000200 R14: ffff888102e91d00 R15: ffffc90002c9faf0 _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+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245