INFO: task kworker/1:0:25 blocked for more than 171 seconds. Not tainted 6.14.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:0 state:D stack:22448 pid:25 tgid:25 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6857 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 schedule_timeout_uninterruptible kernel/time/sleep_timeout.c:158 [inline] msleep+0x9b/0xe0 kernel/time/sleep_timeout.c:318 hub_port_debounce+0x317/0x590 drivers/usb/core/hub.c:4692 hub_port_debounce_be_stable drivers/usb/core/hub.h:183 [inline] hub_port_connect drivers/usb/core/hub.c:5385 [inline] hub_port_connect_change drivers/usb/core/hub.c:5673 [inline] port_event drivers/usb/core/hub.c:5833 [inline] hub_event+0x1f4f/0x5150 drivers/usb/core/hub.c:5915 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 3 locks held by kworker/u8:0/11: 3 locks held by kworker/u8:1/12: 3 locks held by kworker/1:0/25: #0: ffff888020e98548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888020e98548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc900001f7c60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc900001f7c60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffff888028845190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #2: ffff888028845190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1fe/0x5150 drivers/usb/core/hub.c:5861 1 lock held by khungtaskd/30: #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746 3 locks held by kworker/u8:2/35: 6 locks held by kworker/1:2/975: #0: ffff888020e98548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888020e98548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc9000397fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000397fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffff8880289ee190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #2: ffff8880289ee190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1fe/0x5150 drivers/usb/core/hub.c:5861 #3: ffff88805d201190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #3: ffff88805d201190 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x103/0x950 drivers/usb/core/hub.c:2307 #4: ffff8880217bf160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #4: ffff8880217bf160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff8880217bf160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293 #5: ffffffff8f968e08 (input_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:201 [inline] #5: ffffffff8f968e08 (input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x2f3/0x620 drivers/input/input.c:2221 2 locks held by getty/5590: #0: ffff8880240180a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5825: 5 locks held by kworker/u9:4/5842: #0: ffff8880314a2948 ((wq_completion)hci1){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff8880314a2948 ((wq_completion)hci1){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc9000407fc60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000407fc60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffff88805cec4d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1ec/0x400 net/bluetooth/hci_sync.c:331 #3: ffff88805cec4078 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x9ee/0x1340 net/bluetooth/hci_sync.c:5569 #4: ffffffff8eb3e438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline] #4: ffffffff8eb3e438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x820 kernel/rcu/tree_exp.h:996 3 locks held by kworker/u9:5/5846: #0: ffff8880607cf148 ((wq_completion)hci3){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff8880607cf148 ((wq_completion)hci3){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc9000413fc60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000413fc60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffff888029650d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1ec/0x400 net/bluetooth/hci_sync.c:331 4 locks held by kworker/1:7/5893: #0: ffff88801b081d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801b081d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc900043ffc60 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc900043ffc60 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x99/0xfb0 net/wireless/reg.c:2480 #3: ffff88805e988768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6061 [inline] #3: ffff88805e988768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_leave_invalid_chans net/wireless/reg.c:2468 [inline] #3: ffff88805e988768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_check_chans_work+0x164/0xfb0 net/wireless/reg.c:2483 5 locks held by kworker/u8:8/5922: 3 locks held by kworker/u8:25/5939: #0: ffff88814d7c3948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88814d7c3948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc90004a9fc60 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90004a9fc60 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #2: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4730 3 locks held by kworker/0:8/5948: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc90004a8fc60 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90004a8fc60 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffffffff8eb3e438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline] #2: ffffffff8eb3e438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x820 kernel/rcu/tree_exp.h:996 2 locks held by syz-executor/6827: 1 lock held by dhcpcd/6960: #0: ffff88807f3cd608 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline] #0: ffff88807f3cd608 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline] #0: ffff88807f3cd608 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x90/0x240 net/socket.c:1398 2 locks held by syz-executor/6988: 1 lock held by syz-executor/6992: 4 locks held by udevd/7764: #0: ffff888055895418 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb4/0xd70 fs/seq_file.c:182 #1: ffff8880248cfc88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x53/0x3b0 fs/kernfs/file.c:154 #2: ffff8880324d93c8 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x72/0x3b0 fs/kernfs/file.c:155 #3: ffff88805d201190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #3: ffff88805d201190 (&dev->mutex){....}-{4:4}, at: uevent_show+0x17d/0x340 drivers/base/core.c:2729 2 locks held by syz-executor/8398: #0: ffffffff8fec8a10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512 #1: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878 2 locks held by syz-executor/8399: #0: ffffffff8fec8a10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512 #1: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x84/0x290 net/ipv4/nexthop.c:3878 1 lock held by dhcpcd-run-hook/8401: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:399 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5842 Comm: kworker/u9:4 Not tainted 6.14.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: hci3 hci_cmd_timeout RIP: 0010:io_serial_in+0x76/0xb0 drivers/tty/serial/8250/8250_port.c:409 Code: f0 e9 3d fc 89 e9 41 d3 e6 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 11 24 a5 fc 44 03 33 44 89 f2 ec <0f> b6 c0 5b 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c RSP: 0018:ffffc9000407f298 EFLAGS: 00000002 RAX: 1ffffffff3532c00 RBX: ffffffff9a9960a0 RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020 RBP: 0000000000000000 R08: ffffffff8583d406 R09: 1ffff110049cb046 R10: dffffc0000000000 R11: ffffffff8583d3c0 R12: 0000000000000020 R13: 1ffffffff3532c66 R14: 00000000000003fd R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd5bd75848 CR3: 000000007ddf4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_in drivers/tty/serial/8250/8250.h:137 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline] wait_for_lsr+0x1b1/0x320 drivers/tty/serial/8250/8250_port.c:2100 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3357 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3380 [inline] serial8250_console_write+0x134c/0x1e00 drivers/tty/serial/8250/8250_port.c:3465 console_emit_next_record kernel/printk/printk.c:3122 [inline] console_flush_all+0x869/0xeb0 kernel/printk/printk.c:3210 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline] console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3309 vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2432 _printk+0xd5/0x120 kernel/printk/printk.c:2457 bt_err+0x127/0x180 net/bluetooth/lib.c:296 hci_cmd_timeout+0xdd/0x1e0 net/bluetooth/hci_core.c:1452 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244