INFO: task kworker/1:5:5277 blocked for more than 147 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:5 state:D stack:22072 pid:5277 tgid:5277 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: 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 class_mutex_constructor include/linux/mutex.h:253 [inline] usb_audio_probe+0x38f/0x3a90 sound/usb/card.c:950 usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:643 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:721 __driver_probe_device+0x1de/0x400 drivers/base/dd.c:863 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:893 __device_attach_driver+0x1df/0x340 drivers/base/dd.c:1021 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1093 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1148 bus_probe_device+0x64/0x160 drivers/base/bus.c:613 device_add+0x11d9/0x1950 drivers/base/core.c:3691 usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:643 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:721 __driver_probe_device+0x1de/0x400 drivers/base/dd.c:863 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:893 __device_attach_driver+0x1df/0x340 drivers/base/dd.c:1021 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1093 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1148 bus_probe_device+0x64/0x160 drivers/base/bus.c:613 device_add+0x11d9/0x1950 drivers/base/core.c:3691 usb_new_device.cold+0x685/0x115c drivers/usb/core/hub.c:2695 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x314d/0x4af0 drivers/usb/core/hub.c:5953 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 Showing all locks held in the system: 3 locks held by kworker/0:1/10: #0: ffff88810006b148 ( (wq_completion)events ){+.+.}-{0:0} , at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc900000afd18 ( (work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffff88810af031e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #2: ffff88810af031e0 (&dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_fail drivers/net/wireless/ath/ath9k/hif_usb.c:1161 [inline] #2: ffff88810af031e0 (&dev->mutex){....}-{4:4}, at: ath9k_hif_usb_firmware_cb+0x3b5/0x530 drivers/net/wireless/ath/ath9k/hif_usb.c:1294 6 locks held by kworker/1:1/28: #0: ffff888102ac2548 ( (wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc900001e7d18 ( (work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffff88810b3831e0 ( &dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] ){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff88811439b1e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #4: ffff88813d7c51a8 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #5: ffffffff8aa21188 (register_mutex #3 ){+.+.}-{4:4} , at: class_mutex_constructor include/linux/mutex.h:253 [inline] , at: usb_audio_probe+0x38f/0x3a90 sound/usb/card.c:950 1 lock held by khungtaskd/30: #0: ffffffff896de760 ( rcu_read_lock ){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] , at: rcu_read_lock include/linux/rcupdate.h:850 [inline] , at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by getty/2915: #0: ffff88811556b0a0 ( &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/5228: #0: ffff8881131af668 ( &p->lock ){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183 #1: ffff88811a156888 ( &of->mutex #2 ){+.+.}-{4:4} , at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff88811aecb3c8 ( kn->active#28){++++}-{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: ffff88811439b1e0 ( &dev->mutex ){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:954 [inline] ){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 6 locks held by kworker/1:5/5277: #0: ffff888102ac2548 ( (wq_completion)usb_hub_wq ){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc90002aafd18 ((work_completion)(&hub->events) ){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffff88810b33b1e0 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff88813dd491e0 (&dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] ){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #4: ffff8881056da1a8 (&dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #5: ffffffff8aa21188 ( register_mutex#3){+.+.}-{4:4} , at: class_mutex_constructor include/linux/mutex.h:253 [inline] , at: usb_audio_probe+0x38f/0x3a90 sound/usb/card.c:950 4 locks held by udevd/5278: #0: ffff8881180c38b8 (&p->lock){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183 #1: ffff8881121b4c88 ( &of->mutex #2 ){+.+.}-{4:4} , at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff8881346e43c8 ( kn->active #28 ){++++}-{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: ffff88813c67b1e0 ( &dev->mutex ){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:954 [inline] ){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 4 locks held by udevd/5286: #0: ffff88812050e418 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183 #1: ffff888132e72488 (&of->mutex#2){+.+.}-{4:4} , at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff888134080878 (kn->active #28 ){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] ){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff88813dd491e0 (&dev->mutex ){....}-{4:4} , at: device_lock_interruptible include/linux/device.h:954 [inline] , at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 4 locks held by udevd/5365: #0: ffff888114a3c418 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183 #1: ffff888112d7e888 (&of->mutex#2 ){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff888114f50878 (kn->active#28){++++}-{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: ffff888133ca31e0 ( &dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:954 [inline] &dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 6 locks held by kworker/0:7/5449: #0: ffff888102ac2548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc900051efd18 ((work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffff88810af031e0 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff888133ca31e0 (&dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] ){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #4: ffff888135e3a1a8 ( &dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #5: ffffffff8aa21188 ( register_mutex #3 ){+.+.}-{4:4} , at: class_mutex_constructor include/linux/mutex.h:253 [inline] , at: usb_audio_probe+0x38f/0x3a90 sound/usb/card.c:950 6 locks held by kworker/0:8/7365: #0: ffff888102ac2548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc9001687fd18 ( (work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffff88810af9b1e0 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff8881148cb1e0 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #4: ffff88813cabf1a8 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:949 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068 #5: ffffffff8aa21188 ( register_mutex #3 ){+.+.}-{4:4} , at: class_mutex_constructor include/linux/mutex.h:253 [inline] , at: usb_audio_probe+0x38f/0x3a90 sound/usb/card.c:950 4 locks held by kworker/1:8/7712: 11 locks held by kworker/1:7/10594: ============================================= 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 03/18/2026 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: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 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 10594 Comm: kworker/1:7 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: usb_hub_wq hub_event RIP: 0010:info_print_prefix+0x84/0x350 kernel/printk/printk.c:1381 Code: f1 f1 c7 42 04 00 04 f3 f3 65 48 8b 15 2d 81 64 0b 48 89 54 24 68 31 d2 e8 59 0d 21 00 44 89 f6 31 ff 45 31 f6 e8 9c 07 21 00 <8b> 44 24 0c 84 c0 0f 85 d8 01 00 00 e8 3b 0d 21 00 0f b6 34 24 31 RSP: 0018:ffffc900165b6138 EFLAGS: 00000297 RAX: 0000000000000002 RBX: ffffc900165b6258 RCX: ffffffff8190eef4 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888134b3d880 RBP: ffffc900165b6388 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 000000000051ddd8 R12: 1ffff92002cb6c29 R13: 0000000000000001 R14: 0000000000000000 R15: ffffc900165b6258 FS: 0000000000000000(0000) GS:ffff8882687c9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff2d848e20 CR3: 00000001169be000 CR4: 00000000003506f0 Call Trace: record_print_text+0x143/0x3c0 kernel/printk/printk.c:1434 printk_get_next_message+0x2d1/0x6c0 kernel/printk/printk.c:3072 console_emit_next_record kernel/printk/printk.c:3137 [inline] console_flush_one_record+0x67c/0xe50 kernel/printk/printk.c:3269 console_flush_all kernel/printk/printk.c:3343 [inline] __console_flush_and_unlock kernel/printk/printk.c:3373 [inline] console_unlock+0x103/0x260 kernel/printk/printk.c:3413 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479 dev_vprintk_emit+0x394/0x3e0 drivers/base/core.c:4915 dev_printk_emit+0xd2/0x10d drivers/base/core.c:4926 __dev_printk+0xcb/0x100 drivers/base/core.c:4938 _dev_err+0xef/0x127 drivers/base/core.c:4981 parse_uac2_sample_rate_range.cold+0x100/0x135 sound/usb/format.c:468 parse_audio_format_rates_v2v3+0x2fe/0xf70 sound/usb/format.c:689 parse_audio_format_ii sound/usb/format.c:847 [inline] snd_usb_parse_audio_format.cold+0x48c/0x4cc sound/usb/format.c:868 snd_usb_get_audioformat_uac12 sound/usb/stream.c:856 [inline] __snd_usb_parse_audio_interface+0xa85/0x4710 sound/usb/stream.c:1201 snd_usb_parse_audio_interface+0x81/0x110 sound/usb/stream.c:1282 create_standard_audio_quirk+0x6b/0x120 sound/usb/quirks.c:101 snd_usb_create_quirk sound/usb/quirks.c:541 [inline] create_composite_quirk+0x257/0x510 sound/usb/quirks.c:49 snd_usb_create_quirk+0xad/0xf0 sound/usb/quirks.c:541 usb_audio_probe+0x992/0x3a90 sound/usb/card.c:1023 usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:643 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:721 __driver_probe_device+0x1de/0x400 drivers/base/dd.c:863 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:893 __device_attach_driver+0x1df/0x340 drivers/base/dd.c:1021 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1093 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1148 bus_probe_device+0x64/0x160 drivers/base/bus.c:613 device_add+0x11d9/0x1950 drivers/base/core.c:3691 usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:643 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:721 __driver_probe_device+0x1de/0x400 drivers/base/dd.c:863 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:893 __device_attach_driver+0x1df/0x340 drivers/base/dd.c:1021 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1093 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1148 bus_probe_device+0x64/0x160 drivers/base/bus.c:613 device_add+0x11d9/0x1950 drivers/base/core.c:3691 usb_new_device.cold+0x685/0x115c drivers/usb/core/hub.c:2695 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x314d/0x4af0 drivers/usb/core/hub.c:5953 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