INFO: task syz.7.3114:16533 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.3114      state:D stack:29136 pid:16533 ppid:6441   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6698
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x548/0xae0 kernel/locking/mutex.c:747
 device_lock include/linux/device.h:885 [inline]
 usbdev_do_ioctl drivers/usb/core/devio.c:2609 [inline]
 usbdev_ioctl+0x143/0x1f20 drivers/usb/core/devio.c:2817
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1424b9e159
RSP: 002b:00007f14229d3028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f1424e26270 RCX: 00007f1424b9e159
RDX: 0000200000000140 RSI: 0000000080045505 RDI: 0000000000000005
RBP: 00007f1424c3503b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1424e26308 R14: 00007f1424e26270 R15: 00007ffcbaff9568
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8cb2e5b0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8cb2edd0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
 #0: ffffffff8cb2dc20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8cb2dc20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8cb2dc20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527
2 locks held by getty/4026:
 #0: ffff88814dee4098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198
5 locks held by kworker/u4:7/4347:
 #0: ffff88801761e938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
 #1: ffffc900049cfd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
 #2: ffffffff8dd4fa90 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:594
 #3: ffff8880588a93e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_destruct+0x112/0x300 drivers/net/wireguard/device.c:249
 #4: ffffffff8cb338f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
 #4: ffffffff8cb338f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962
2 locks held by kworker/1:2/13124:
 #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
 #1: ffffc9000537fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
1 lock held by syz-executor/15386:
 #0: ffffffff8cb338f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
 #0: ffffffff8cb338f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962
7 locks held by syz.7.3114/16532:
 #0: ffff88802782a190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
 #0: ffff88802782a190 (&dev->mutex){....}-{3:3}, at: usbdev_do_ioctl drivers/usb/core/devio.c:2609 [inline]
 #0: ffff88802782a190 (&dev->mutex){....}-{3:3}, at: usbdev_ioctl+0x143/0x1f20 drivers/usb/core/devio.c:2817
 #1: ffff88802782b118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
 #1: ffff88802782b118 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1099 [inline]
 #1: ffff88802782b118 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb1/0x7c0 drivers/base/dd.c:1302
 #2: ffff888055517190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
 #2: ffff888055517190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0xf8/0x8a0 drivers/usb/core/hub.c:2310
 #3: ffff888062fe9118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
 #3: ffff888062fe9118 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1099 [inline]
 #3: ffff888062fe9118 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb1/0x7c0 drivers/base/dd.c:1302
 #4: ffffffff8dd016a8 (register_mutex#7){+.+.}-{3:3}, at: usb_audio_disconnect+0xd0/0x6f0 sound/usb/card.c:960
 #5: ffff888058062170 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
 #5: ffff888058062170 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1099 [inline]
 #5: ffff888058062170 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb1/0x7c0 drivers/base/dd.c:1302
 #6: ffffffff8dcc7368 (register_mutex#6){+.+.}-{3:3}, at: snd_seq_midisynth_remove+0x68/0x4f0 sound/core/seq/seq_midi.c:459
1 lock held by syz.7.3114/16533:
 #0: ffff88802782a190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
 #0: ffff88802782a190 (&dev->mutex){....}-{3:3}, at: usbdev_do_ioctl drivers/usb/core/devio.c:2609 [inline]
 #0: ffff88802782a190 (&dev->mutex){....}-{3:3}, at: usbdev_ioctl+0x143/0x1f20 drivers/usb/core/devio.c:2817
3 locks held by syz-executor/17236:
 #0: ffff88803c02d1e0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
 #0: ffff88803c02d1e0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x20e/0x500 net/bluetooth/hci_core.c:2717
 #1: ffff88803c02c428 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x506/0x1040 net/bluetooth/hci_sync.c:5292
 #2: ffffffff8debad88 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1821 [inline]
 #2: ffffffff8debad88 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xac/0x290 net/bluetooth/hci_conn.c:2549
2 locks held by syz.8.3413/17888:
 #0: ffff8880398691e0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
 #0: ffff8880398691e0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x20e/0x500 net/bluetooth/hci_core.c:2717
 #1: ffff888039868428 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x506/0x1040 net/bluetooth/hci_sync.c:5292
2 locks held by rm/17901:

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

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf0e/0xf50 kernel/hung_task.c:377
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 11 Comm: kworker/u4:1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:kasan_check_range+0x0/0x290 mm/kasan/generic.c:188
Code: 48 01 c6 48 89 c7 e8 cf 7f 5e 08 31 c0 c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc <b0> 01 48 85 f6 0f 84 ac 01 00 00 55 41 57 41 56 41 54 53 49 89 f8
RSP: 0018:ffffc90000107b30 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff888054770000 RCX: ffffffff882ef93a
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff8880554ef4a4
RBP: 0000000000001100 R08: ffff8880554ef487 R09: ffff8880554ef3c0
R10: dffffc0000000000 R11: ffffed100aa9de91 R12: 0000000000001000
R13: dffffc0000000000 R14: ffff8880554ef3c0 R15: ffff8880554ef4a4
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd64ba9beb8 CR3: 000000007e486000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 instrument_atomic_write include/linux/instrumented.h:87 [inline]
 atomic_set include/linux/atomic/atomic-instrumented.h:41 [inline]
 refcount_set include/linux/refcount.h:136 [inline]
 __build_skb_around net/core/skbuff.c:283 [inline]
 __alloc_skb+0x2fa/0x7d0 net/core/skbuff.c:530
 alloc_skb include/linux/skbuff.h:1303 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
 nsim_dev_trap_report_work+0x24f/0xa80 drivers/net/netdevsim/dev.c:851
 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>