INFO: task syz.3.3305:21021 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.3305      state:D stack:26504 pid:21021 tgid:21020 ppid:17537  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x1295/0x67a0 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]
 usbdev_open+0x1b6/0x870 drivers/usb/core/devio.c:1054
 chrdev_open+0x234/0x6a0 fs/char_dev.c:411
 do_dentry_open+0x6d8/0x1660 fs/open.c:947
 vfs_open+0x82/0x3f0 fs/open.c:1079
 do_open fs/namei.c:4699 [inline]
 path_openat+0x208c/0x31a0 fs/namei.c:4858
 do_file_open+0x20e/0x430 fs/namei.c:4887
 do_sys_openat2+0x10d/0x1e0 fs/open.c:1364
 do_sys_open fs/open.c:1370 [inline]
 __do_sys_openat fs/open.c:1386 [inline]
 __se_sys_openat fs/open.c:1381 [inline]
 __x64_sys_openat+0x12d/0x210 fs/open.c:1381
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f949135d68e
RSP: 002b:00007f949222bb28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f949222c6c0 RCX: 00007f949135d68e
RDX: 0000000000000082 RSI: 00007f949222bc00 RDI: ffffffffffffff9c
RBP: 00007f949222bc00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007f9491616038 R14: 00007f9491615fa0 R15: 00007ffe93acfcf8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8e7e5620 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8e7e5620 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8e7e5620 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:5/134:
4 locks held by kworker/u8:8/1156:
 #0: ffff88801c6c0940 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
 #1: ffffc90005637d08 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
 #2: ffffffff905f5548 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:673
 #3: ffffffff8e7f1168 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
2 locks held by kworker/u9:1/4929:
 #0: ffff88802816a140 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
 #1: ffffc900091f7d08 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
2 locks held by getty/5367:
 #0: ffff8880398a80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211
2 locks held by kworker/u9:4/5620:
 #0: ffff88802816a140 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
 #1: ffffc900043d7d08 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
2 locks held by kworker/u9:5/5621:
 #0: ffff88802816a140 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
 #1: ffffc900043e7d08 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
8 locks held by kworker/1:8/11952:
2 locks held by kworker/0:4/16524:
 #0: ffff88813fe5b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
 #1: ffffc90006b6fd08 ((work_completion)(&m->mpeg_thread)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
1 lock held by syz.3.3305/21021:
 #0: ffff88802b2c31d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
 #0: ffff88802b2c31d8 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x1b6/0x870 drivers/usb/core/devio.c:1054

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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: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+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 11952 Comm: kworker/1:8 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:lockdep_recursion_inc kernel/locking/lockdep.c:465 [inline]
RIP: 0010:lock_release kernel/locking/lockdep.c:5888 [inline]
RIP: 0010:lock_release+0x8e/0x310 kernel/locking/lockdep.c:5875
Code: 00 65 4c 8b 25 7b cc 26 12 41 8b bc 24 8c 0b 00 00 85 ff 0f 85 21 01 00 00 48 81 3b 00 27 12 94 0f 84 14 01 00 00 9c 41 5e fa <48> c7 c7 12 55 01 8e e8 66 a5 a6 09 65 ff 05 b7 13 27 12 8b 35 0d
RSP: 0018:ffffc90000a08740 EFLAGS: 00000002
RAX: 0000000000000000 RBX: ffffffff8e7e5620 RCX: ffffffff91ca7c01
RDX: 0000000000000000 RSI: ffffffff8c1c4100 RDI: 0000000000000000
RBP: ffffffff81b7d1ae R08: 0000000000000001 R09: 0000000000000007
R10: 0000000000000000 R11: 000000000005367b R12: ffff888035152500
R13: ffffc90000a087f8 R14: 0000000000000002 R15: ffffc90000a0882c
FS:  0000000000000000(0000) GS:ffff88812446a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff27bdea2f8 CR3: 0000000076555000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 rcu_lock_release include/linux/rcupdate.h:310 [inline]
 rcu_read_unlock include/linux/rcupdate.h:869 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1181 [inline]
 unwind_next_frame+0x3c3/0x2090 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+0x5f/0x80 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:6251 [inline]
 kfree+0x223/0x6c0 mm/slub.c:6566
 urb_destroy drivers/usb/core/urb.c:27 [inline]
 kref_put include/linux/kref.h:65 [inline]
 usb_free_urb.part.0+0xa5/0x110 drivers/usb/core/urb.c:96
 usb_free_urb+0x1f/0x30 drivers/usb/core/urb.c:95
 usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741
 dummy_timer+0xda1/0x36c0 drivers/usb/gadget/udc/dummy_hcd.c:2005
 __run_hrtimer kernel/time/hrtimer.c:1930 [inline]
 __hrtimer_run_queues+0x470/0xa00 kernel/time/hrtimer.c:1994
 hrtimer_run_softirq+0x17d/0x2c0 kernel/time/hrtimer.c:2011
 handle_softirqs+0x1ea/0xa00 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x162/0x210 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+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1061
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:its_return_thunk+0x0/0x10 arch/x86/lib/retpoline.S:417
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc <c3> cc 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 e9 9b 1f e7 f5 cc
RSP: 0018:ffffc9000a37e998 EFLAGS: 00000246
RAX: ffffffff87553f2d RBX: ffffc9000a37e9a0 RCX: ffffc9000a37e8f4
RDX: 1ffff9200146fd3d RSI: ffffffff8defe91b RDI: ffffffff87553f2d
RBP: ffffc9000a37ea30 R08: 0000000000000001 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000004df4 R12: ffffffff81f2f5b0
R13: ffffc9000a37ea60 R14: 0000000000000000 R15: ffff888035152500
 arch_stack_walk+0xa6/0xf0 arch/x86/kernel/stacktrace.c:26
 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
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kmalloc_noprof include/linux/slab.h:950 [inline]
 dummy_urb_enqueue+0xa3/0x880 drivers/usb/gadget/udc/dummy_hcd.c:1277
 usb_hcd_submit_urb+0x26c/0x2150 drivers/usb/core/hcd.c:1542
 usb_submit_urb+0x8aa/0x1910 drivers/usb/core/urb.c:586
 ath6kl_usb_post_recv_transfers.constprop.0+0x204/0x3d0 drivers/net/wireless/ath/ath6kl/usb.c:449
 ath6kl_usb_start_recv_pipes drivers/net/wireless/ath/ath6kl/usb.c:497 [inline]
 hif_start drivers/net/wireless/ath/ath6kl/usb.c:702 [inline]
 ath6kl_usb_power_on+0x8e/0x160 drivers/net/wireless/ath/ath6kl/usb.c:1061
 ath6kl_hif_power_on drivers/net/wireless/ath/ath6kl/hif-ops.h:136 [inline]
 ath6kl_core_init+0x173/0x11b0 drivers/net/wireless/ath/ath6kl/core.c:97
 ath6kl_usb_probe+0xae7/0x13a0 drivers/net/wireless/ath/ath6kl/usb.c:1162
 usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:631 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:709
 __driver_probe_device+0x22e/0x480 drivers/base/dd.c:871
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:901
 __device_attach_driver+0x1df/0x340 drivers/base/dd.c:1029
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1101
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1156
 bus_probe_device+0x64/0x160 drivers/base/bus.c:613
 device_add+0x1210/0x1950 drivers/base/core.c:3706
 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:631 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:709
 __driver_probe_device+0x22e/0x480 drivers/base/dd.c:871
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:901
 __device_attach_driver+0x1df/0x340 drivers/base/dd.c:1029
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1101
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1156
 bus_probe_device+0x64/0x160 drivers/base/bus.c:613
 device_add+0x1210/0x1950 drivers/base/core.c:3706
 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+0xa0e/0x1980 kernel/workqueue.c:3314
 process_scheduled_works kernel/workqueue.c:3397 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>