INFO: task kworker/0:2:92 blocked for more than 143 seconds.
Not tainted 6.16.0-rc3-next-20250627-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:2 state:D stack:20904 pid:92 tgid:92 ppid:2 task_flags:0x4288060 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5313 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6696
__schedule_loop kernel/sched/core.c:6774 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6789
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153
__flush_work+0x9b9/0xbc0 kernel/workqueue.c:4247
flush_work kernel/workqueue.c:4268 [inline]
flush_delayed_work+0x13e/0x190 kernel/workqueue.c:4290
hub_quiesce+0x1f0/0x330 drivers/usb/core/hub.c:1421
hub_disconnect+0xc8/0x470 drivers/usb/core/hub.c:1821
usb_unbind_interface+0x26e/0x910 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:569 [inline]
__device_release_driver drivers/base/dd.c:1272 [inline]
device_release_driver_internal+0x4d9/0x7c0 drivers/base/dd.c:1295
bus_remove_device+0x34d/0x410 drivers/base/bus.c:579
device_del+0x511/0x8e0 drivers/base/core.c:3880
usb_disable_device+0x3e9/0x8a0 drivers/usb/core/message.c:1418
usb_disconnect+0x330/0x950 drivers/usb/core/hub.c:2349
hub_port_connect drivers/usb/core/hub.c:5411 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5711 [inline]
port_event drivers/usb/core/hub.c:5871 [inline]
hub_event+0x1cdb/0x4a00 drivers/usb/core/hub.c:5953
process_one_work kernel/workqueue.c:3239 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task kworker/0:1:12190 blocked for more than 144 seconds.
Not tainted 6.16.0-rc3-next-20250627-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:1 state:D stack:23832 pid:12190 tgid:12190 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: events_power_efficient hub_init_func2
Call Trace:
context_switch kernel/sched/core.c:5313 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6696
__schedule_loop kernel/sched/core.c:6774 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6789
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6846
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
device_lock include/linux/device.h:884 [inline]
hub_activate+0xb7/0x1ea0 drivers/usb/core/hub.c:1096
process_one_work kernel/workqueue.c:3239 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
1 lock held by ksoftirqd/1/23:
5 locks held by kworker/1:0/24:
#0: ffff888021ec5d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff888021ec5d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc900001e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc900001e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff888145fb9198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#2: ffff888145fb9198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a00 drivers/usb/core/hub.c:5899
#3: ffff88807bb36198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#3: ffff88807bb36198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1004
#4: ffff888078ff3160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#4: ffff888078ff3160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1004
1 lock held by khungtaskd/31:
#0: ffffffff8e33bf20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e33bf20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e33bf20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
5 locks held by kworker/u8:2/36:
5 locks held by kworker/0:2/92:
#0: ffff888021ec5d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff888021ec5d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc900025e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc900025e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff888028201198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#2: ffff888028201198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a00 drivers/usb/core/hub.c:5899
#3: ffff88804755f198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#3: ffff88804755f198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0xf8/0x950 drivers/usb/core/hub.c:2340
#4: ffff888087978160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#4: ffff888087978160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1094 [inline]
#4: ffff888087978160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x7c0 drivers/base/dd.c:1292
1 lock held by klogd/5190:
#0: ffff8880b8739f58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
2 locks held by getty/5595:
#0: ffff8880346de0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000331b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/0:1/12190:
#0: ffff88801a882148 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff88801a882148 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc9000d3f7bc0 ((work_completion)(&(&hub->init_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc9000d3f7bc0 ((work_completion)(&(&hub->init_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff88804755f198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#2: ffff88804755f198 (&dev->mutex){....}-{4:4}, at: hub_activate+0xb7/0x1ea0 drivers/usb/core/hub.c:1096
3 locks held by kworker/u9:1/14308:
#0: ffff88807d03c148 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff88807d03c148 ((wq_completion)hci0){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc900041c7bc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc900041c7bc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff888030544dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0 net/bluetooth/hci_sync.c:331
1 lock held by syz.7.2864/17060:
#0: ffff888028201198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#0: ffff888028201198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054
2 locks held by kworker/u8:0/18537:
1 lock held by syz.6.3519/19219:
#0: ffff8880b8739f58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
1 lock held by dhcpcd/19255:
#0: ffff888045621a08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#0: ffff888045621a08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:648 [inline]
#0: ffff888045621a08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1439
2 locks held by dhcpcd/19256:
#0: ffff8880563ed608 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#0: ffff8880563ed608 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:648 [inline]
#0: ffff8880563ed608 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1439
#1: ffffffff8e341a38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8e341a38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:967
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc3-next-20250627-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
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: 5839 Comm: kworker/u9:2 Not tainted 6.16.0-rc3-next-20250627-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: hci0 hci_cmd_timeout
RIP: 0010:rb_next+0x96/0xe0 lib/rbtree.c:517
Code: 74 c6 49 89 c6 48 8d 58 10 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 e3 48 89 df e8 95 3e b2 f6 eb d9 49 3b 5e 08 4c 89 f3 75 9e <48> 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 74 3e b2 f6
RSP: 0018:ffffc90000a08ce8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffc9000532fd40 RCX: ffff888077765a00
RDX: 0000000000010000 RSI: ffffc9000532fd40 RDI: ffffc9000532fd40
RBP: 1ffff92000a65fa8 R08: ffffffff8fc2ac37 R09: 1ffffffff1f85586
R10: dffffc0000000000 R11: fffffbfff1f85587 R12: ffff8880b8727b98
R13: dffffc0000000000 R14: ffffc9000532fd48 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888125ae6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1c2359ed58 CR3: 0000000075e8a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000005325
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
rb_erase_cached include/linux/rbtree.h:124 [inline]
timerqueue_del+0x8a/0x100 lib/timerqueue.c:57
__remove_hrtimer kernel/time/hrtimer.c:1121 [inline]
__run_hrtimer kernel/time/hrtimer.c:1741 [inline]
__hrtimer_run_queues+0x364/0xc60 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2061 [inline]
RIP: 0010:vprintk_emit+0x58f/0x7a0 kernel/printk/printk.c:2449
Code: 85 32 01 00 00 e8 f1 6d 1f 00 41 89 df 4d 85 f6 48 8b 1c 24 75 07 e8 e0 6d 1f 00 eb 06 e8 d9 6d 1f 00 fb 48 c7 c7 c0 01 33 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 a9 36
RSP: 0018:ffffc90003f27720 EFLAGS: 00000293
RAX: ffffffff81a0b487 RBX: ffffffff81a0b344 RCX: ffff888077765a00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e3301c0
RBP: ffffc90003f27830 R08: ffffffff8fc2ac37 R09: 1ffffffff1f85586
R10: dffffc0000000000 R11: fffffbfff1f85587 R12: dffffc0000000000
R13: 1ffff920007e4ee8 R14: 0000000000000200 R15: 000000000000002a
_printk+0xcf/0x120 kernel/printk/printk.c:2475
bt_err+0x10b/0x160 net/bluetooth/lib.c:296
hci_cmd_timeout+0xd8/0x1e0 net/bluetooth/hci_core.c:1469
process_one_work kernel/workqueue.c:3239 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245