INFO: task kworker/u9:0:51 blocked for more than 143 seconds. Not tainted 6.16.0-rc2-syzkaller-00082-gfb4d33ab452e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u9:0 state:D stack:26568 pid:51 tgid:51 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: hci4 hci_cmd_sync_work Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6878 exp_funnel_lock+0x346/0x3c0 kernel/rcu/tree_exp.h:327 synchronize_rcu_expedited+0x28e/0x460 kernel/rcu/tree_exp.h:998 hci_chan_del+0x11d/0x230 net/bluetooth/hci_conn.c:2722 l2cap_conn_del+0x475/0x730 net/bluetooth/l2cap_core.c:1798 l2cap_connect_cfm+0x9e1/0xf80 net/bluetooth/l2cap_core.c:7236 hci_connect_cfm include/net/bluetooth/hci_core.h:2054 [inline] hci_conn_failed+0x1ba/0x330 net/bluetooth/hci_conn.c:1275 hci_abort_conn_sync+0x762/0xb10 net/bluetooth/hci_sync.c:5645 abort_conn_sync+0x197/0x360 net/bluetooth/hci_conn.c:2885 hci_cmd_sync_work+0x1a8/0x430 net/bluetooth/hci_sync.c:332 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 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: 5 locks held by kworker/u8:1/13: 1 lock held by khungtaskd/31: #0: ffffffff8e5c4880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c4880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c4880 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770 1 lock held by khugepaged/38: 7 locks held by kworker/1:1/42: #0: ffff88801bf00948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90000b27d10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888144781198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #2: ffff888144781198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4fa0 drivers/usb/core/hub.c:5863 #3: ffff8880586fc198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #3: ffff8880586fc198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x920 drivers/usb/core/hub.c:2307 #4: ffff88802a32e160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #4: ffff88802a32e160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #4: ffff88802a32e160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xa4/0x620 drivers/base/dd.c:1292 #5: ffffffff8fb826e8 (input_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:225 [inline] #5: ffffffff8fb826e8 (input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x156/0x470 drivers/input/input.c:2221 #6: ffffffff8e5cfe78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:336 6 locks held by kworker/u9:0/51: 3 locks held by kworker/u8:5/1092: 4 locks held by kworker/1:2/2154: 1 lock held by udevd/5189: 2 locks held by getty/5577: #0: ffff88814c33f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5821: 3 locks held by kworker/0:6/5904: 5 locks held by kworker/0:7/5927: #0: ffff88801bf00948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900044bfd10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888144799198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #2: ffff888144799198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4fa0 drivers/usb/core/hub.c:5863 #3: ffff88802756e198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #3: ffff88802756e198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1004 #4: ffff88807b3d1160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #4: ffff88807b3d1160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1004 3 locks held by kworker/u8:8/6038: 4 locks held by kworker/u8:9/6041: 3 locks held by kworker/u8:10/6043: #0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900055e7d10 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888026628768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6062 [inline] #2: ffff888026628768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0x99/0x550 net/wireless/core.c:421 2 locks held by kworker/u8:11/7947: 3 locks held by kworker/u8:12/10459: #0: ffff88801b881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900044ffd10 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888079928768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6062 [inline] #2: ffff888079928768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0x99/0x550 net/wireless/core.c:421 2 locks held by syz-executor/11652: 3 locks held by kworker/u8:13/11729: 1 lock held by syz.6.1984/13272: 1 lock held by dhcpcd/13287: 2 locks held by dhcpcd/13290: 1 lock held by dhcpcd/13292: 1 lock held by dhcpcd/13293: #0: ffff888036dee258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1667 [inline] #0: ffff888036dee258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf60 net/packet/af_packet.c:3252 1 lock held by dhcpcd/13294: #0: ffff88807a226258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1667 [inline] #0: ffff88807a226258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf60 net/packet/af_packet.c:3252 1 lock held by dhcpcd/13297: #0: ffff888055268258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1667 [inline] #0: ffff888055268258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf60 net/packet/af_packet.c:3252 4 locks held by syz-executor/13298: 1 lock held by dhcpcd/13299: #0: ffff88805631e258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1667 [inline] #0: ffff88805631e258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf60 net/packet/af_packet.c:3252 1 lock held by dhcpcd/13300: #0: ffff888077e6c258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1667 [inline] #0: ffff888077e6c258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf60 net/packet/af_packet.c:3252 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc2-syzkaller-00082-gfb4d33ab452e #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:470 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.16.0-rc2-syzkaller-00082-gfb4d33ab452e #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 7b 72 02 e9 03 fb 02 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d a3 00 2a 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffffff8e207e08 EFLAGS: 000002c2 RAX: 0000000002bcb8e5 RBX: 0000000000000000 RCX: ffffffff8b800c19 RDX: 0000000000000000 RSI: ffffffff8de1a120 RDI: ffffffff8c1579e0 RBP: fffffbfff1c52ef0 R08: 0000000000000001 R09: ffffed1017086645 R10: ffff8880b843322b R11: 0000000000000001 R12: 0000000000000000 R13: ffffffff8e297780 R14: ffffffff90a81550 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124753000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f589b781ef8 CR3: 0000000047339000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:749 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 rest_init+0x16b/0x2b0 init/main.c:745 start_kernel+0x3ee/0x4d0 init/main.c:1102 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x148