INFO: task kworker/1:10:13979 blocked for more than 149 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:10 state:D stack:20936 pid:13979 ppid:2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6a9/0xcc0 kernel/locking/mutex.c:747
usb_audio_probe+0x3b3/0x1df0 sound/usb/card.c:813
usb_probe_interface+0x5c9/0xb20 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x25b/0xb20 drivers/base/dd.c:658
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
__device_attach_driver+0x2ca/0x510 drivers/base/dd.c:958
bus_for_each_drv+0x252/0x2e0 drivers/base/bus.c:459
__device_attach+0x2c2/0x420 drivers/base/dd.c:1030
bus_probe_device+0x180/0x260 drivers/base/bus.c:534
device_add+0x85b/0xc20 drivers/base/core.c:3683
usb_set_configuration+0x1a79/0x20c0 drivers/usb/core/message.c:2265
usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:238
usb_probe_device+0x13d/0x270 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x25b/0xb20 drivers/base/dd.c:658
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
__device_attach_driver+0x2ca/0x510 drivers/base/dd.c:958
bus_for_each_drv+0x252/0x2e0 drivers/base/bus.c:459
__device_attach+0x2c2/0x420 drivers/base/dd.c:1030
bus_probe_device+0x180/0x260 drivers/base/bus.c:534
device_add+0x85b/0xc20 drivers/base/core.c:3683
usb_new_device+0xa3c/0x1660 drivers/usb/core/hub.c:2660
hub_port_connect drivers/usb/core/hub.c:5529 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5669 [inline]
port_event drivers/usb/core/hub.c:5833 [inline]
hub_event+0x29bf/0x49f0 drivers/usb/core/hub.c:5915
process_one_work kernel/workqueue.c:2653 [inline]
process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/29:
#0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
2 locks held by getty/5528:
#0: ffff888031ec20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000326e2f0
(&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217
10 locks held by kworker/0:9/11119:
2 locks held by kworker/0:0/13804:
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#1:
ffffc900044dfd00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
ffffc900044dfd00 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
2 locks held by kworker/0:7/13974:
#0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#1: ffffc9000b9efd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc9000b9efd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
6 locks held by kworker/1:10/13979:
#0: ffff888019ece138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888019ece138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#1: ffffc9000ba2fd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc9000ba2fd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#2: ffff888141ff4190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:995 [inline]
#2: ffff888141ff4190 (&dev->mutex){....}-{3:3}, at: hub_event+0x180/0x49f0 drivers/usb/core/hub.c:5861
#3: ffff8880531f0190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:995 [inline]
#3: ffff8880531f0190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x89/0x420 drivers/base/dd.c:1005
#4: ffff88802a2df160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:995 [inline]
#4: ffff88802a2df160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x89/0x420 drivers/base/dd.c:1005
#5: ffffffff8e364c68 (register_mutex#6){+.+.}-{3:3}, at: usb_audio_probe+0x3b3/0x1df0 sound/usb/card.c:813
3 locks held by kworker/1:15/13985:
2 locks held by kworker/u4:1/14486:
#0: ffff888140a86938 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888140a86938 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#1: ffffc90004987d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc90004987d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
3 locks held by syz-executor/14724:
#0: ffff88805b788e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
#0: ffff88805b788e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x212/0x500 net/bluetooth/hci_core.c:2709
#1: ffff88805b7880b8 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x5d6/0x1220 net/bluetooth/hci_sync.c:5288
#2:
ffffffff8e5307a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2011 [inline]
ffffffff8e5307a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa1/0x220 net/bluetooth/hci_conn.c:2541
4 locks held by udevd/14835:
#0: ffff88806553eb08 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xb1/0xd50 fs/seq_file.c:182
#1: ffff88801bb3bc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x5c/0x410 fs/kernfs/file.c:172
#2: ffff88814ce94100 (kn->active#26){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff88814ce94100 (kn->active#26){.+.+}-{0:0}, at: kernfs_seq_start+0xb2/0x410 fs/kernfs/file.c:173
#3: ffff8880531f0190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:1000 [inline]
#3: ffff8880531f0190 (&dev->mutex){....}-{3:3}, at: product_show+0x26/0xa0 drivers/usb/core/sysfs.c:141
1 lock held by syz.6.2545/15509:
#0: ffff888141ff4190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:995 [inline]
#0: ffff888141ff4190 (&dev->mutex){....}-{3:3}, at: usbdev_open+0x183/0x770 drivers/usb/core/devio.c:1051
3 locks held by syz-executor/15658:
#0: ffff88805f3ace70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
#0: ffff88805f3ace70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x212/0x500 net/bluetooth/hci_core.c:2709
#1: ffff88805f3ac0b8 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x5d6/0x1220 net/bluetooth/hci_sync.c:5288
#2: ffffffff8e5307a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2011 [inline]
#2: ffffffff8e5307a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa1/0x220 net/bluetooth/hci_conn.c:2541
4 locks held by syz.0.2700/16261:
#0: ffff88807a2e8e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
#0: ffff88807a2e8e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x212/0x500 net/bluetooth/hci_core.c:2709
#1: ffff88807a2e80b8 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x5d6/0x1220 net/bluetooth/hci_sync.c:5288
#2: ffffffff8e5307a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2011 [inline]
#2: ffffffff8e5307a8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa1/0x220 net/bluetooth/hci_conn.c:2541
#3: ffff888078054338 (&conn->lock#2){+.+.}-{3:3}, at: l2cap_conn_del+0x70/0x660 net/bluetooth/l2cap_core.c:1759
2 locks held by dhcpcd/16265:
#0: ffff88805d3a6e20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#0: ffff88805d3a6e20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline]
#0: ffff88805d3a6e20 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x9b/0x230 net/socket.c:1420
#1: ffffffff8d137ab8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#1: ffffffff8d137ab8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004
1 lock held by dhcpcd/16270:
#0: ffff88805d3a7420 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#0: ffff88805d3a7420 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline]
#0: ffff88805d3a7420 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x9b/0x230 net/socket.c:1420
2 locks held by dhcpcd/16275:
#0: ffff88807b294130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline]
#0: ffff88807b294130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcc0 net/packet/af_packet.c:3264
#1: ffffffff8d137ab8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#1: ffffffff8d137ab8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004
1 lock held by dhcpcd/16276:
#0: ffff88802534a130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline]
#0: ffff88802534a130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcc0 net/packet/af_packet.c:3264
1 lock held by dhcpcd/16279:
#0: ffff88807ae6e130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline]
#0: ffff88807ae6e130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcc0 net/packet/af_packet.c:3264
1 lock held by dhcpcd/16281:
#0: ffff88802f32c130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline]
#0: ffff88802f32c130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcc0 net/packet/af_packet.c:3264
1 lock held by dhcpcd-run-hook/16283:
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
<TASK>
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf3d/0xf80 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:pv_native_safe_halt+0xf/0x10 arch/x86/kernel/paravirt.c:148
Code: 19 21 02 c3 cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d e3 d3 41 00 fb f4 <c3> 66 0f 1f 00 55 41 57 41 56 41 54 53 50 8b 2f eb 2e 41 89 de 80
RSP: 0018:ffffc90000187de0 EFLAGS: 000002c6
RAX: c1534c6503b0da00 RBX: ffffffff8162a8f1 RCX: c1534c6503b0da00
RDX: 0000000000000001 RSI: ffffffff8acac9e0 RDI: ffffffff8b1c8fa0
RBP: ffffc90000187f20 R08: ffff8880b8f36b2b R09: 1ffff110171e6d65
R10: dffffc0000000000 R11: ffffed10171e6d66 R12: 1ffff92000030fc8
R13: dffffc0000000000 R14: 1ffff110036cd780 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffca1be27c0 CR3: 0000000064492000 CR4: 00000000003506e0
Call Trace:
<TASK>
arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:753
default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97
cpuidle_idle_call kernel/sched/idle.c:178 [inline]
do_idle+0x221/0x590 kernel/sched/idle.c:302
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:401
start_secondary+0xee/0xf0 arch/x86/kernel/smpboot.c:323
secondary_startup_64_no_verify+0x179/0x17b
</TASK>