INFO: task khidpd_04580009:14065 blocked for more than 143 seconds. Not tainted 6.15.0-rc5-syzkaller-00163-g09db7a4d287d #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:khidpd_04580009 state:D stack:29160 pid:14065 tgid:14065 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:148 __flush_work+0x9b9/0xbc0 kernel/workqueue.c:4244 __cancel_work_sync+0xbe/0x110 kernel/workqueue.c:4364 hidp_session_remove+0x62/0x260 net/bluetooth/hidp/core.c:1169 l2cap_unregister_user+0x18b/0x1b0 net/bluetooth/l2cap_core.c:1733 hidp_session_thread+0x3c9/0x410 net/bluetooth/hidp/core.c:1304 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.3.2594:14119 blocked for more than 144 seconds. Not tainted 6.15.0-rc5-syzkaller-00163-g09db7a4d287d #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.2594 state:D stack:26312 pid:14119 tgid:14118 ppid:5831 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 rfcomm_reparent_device+0x4a/0x450 net/bluetooth/rfcomm/tty.c:187 rfcomm_dev_add net/bluetooth/rfcomm/tty.c:339 [inline] __rfcomm_create_dev net/bluetooth/rfcomm/tty.c:424 [inline] rfcomm_create_dev net/bluetooth/rfcomm/tty.c:485 [inline] rfcomm_dev_ioctl+0x17e6/0x1d40 net/bluetooth/rfcomm/tty.c:584 sock_do_ioctl+0xd9/0x300 net/socket.c:1190 sock_ioctl+0x576/0x790 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8aeb58e969 RSP: 002b:00007f8aec32a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f8aeb7b5fa0 RCX: 00007f8aeb58e969 RDX: 0000200000000100 RSI: 00000000400452c8 RDI: 0000000000000009 RBP: 00007f8aeb610ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f8aeb7b5fa0 R15: 00007fff78322aa8 Showing all locks held in the system: 3 locks held by kworker/0:1/10: #0: ffff8880b8839b58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605 #1: ffff8880b8823b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 #2: ffffffff8df3b860 ( rcu_read_lock ){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] , at: rcu_read_lock include/linux/rcupdate.h:841 [inline] , at: class_rcu_constructor include/linux/rcupdate.h:1155 [inline] , at: unwind_next_frame+0xa5/0x2390 arch/x86/kernel/unwind_orc.c:479 1 lock held by khungtaskd/31: #0: ffffffff8df3b860 ( rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 2 locks held by kworker/u9:0/55: #0: ffff888024abb148 ( (wq_completion)nbd2-recv ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3213 [inline] , at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000121fc60 ( (work_completion)(&args->work) ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3214 [inline] , at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 5 locks held by kworker/u8:7/3458: #0: ffff88801aef6148 ( (wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] (wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000c01fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000c01fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2e7d10 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x145/0xbd0 net/core/net_namespace.c:608 #3: ffff8880587f94e8 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_destruct+0x116/0x2f0 drivers/net/wireguard/device.c:249 #4: ffffffff8df41200 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3774 3 locks held by kworker/u8:8/3490: #0: ffff88802f87c148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88802f87c148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000c1cfc60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000c1cfc60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2f4848 ( rtnl_mutex ){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4198 2 locks held by getty/5589: #0: ffff88803089d0a0 (&tty->ldisc_sem){++++}-{0:0} , at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900033532f0 ( &ldata->atomic_read_lock ){+.+.}-{4:4} , at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 8 locks held by kworker/1:7/5909: 3 locks held by kworker/0:6/5954: #0: ffff88801a080d48 ( (wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] (wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90004b17c60 ( deferred_process_work ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3214 [inline] , at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2f4848 ( rtnl_mutex ){+.+.}-{4:4} , at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 3 locks held by kworker/u8:23/8941: #0: ffff88801a089148 ( (wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] (wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90004ddfc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90004ddfc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2f4848 (rtnl_mutex ){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 2 locks held by syz-executor/14017: #0: ffff88807f6c4d80 ( &hdev->req_lock ){+.+.}-{4:4} , at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] , at: hci_unregister_dev+0x1fe/0x500 net/bluetooth/hci_core.c:2678 #1: ffff88807f6c4078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5213 2 locks held by khidpd_04580009/14065: #0: ffff88807f6c4078 (&hdev->lock){+.+.}-{4:4}, at: l2cap_unregister_user+0x6a/0x1b0 net/bluetooth/l2cap_core.c:1727 #1: ffffffff8f482e90 (hidp_session_sem){++++}-{4:4}, at: hidp_session_remove+0x2c/0x260 net/bluetooth/hidp/core.c:1165 2 locks held by syz.3.2594/14119: #0: ffffffff8f47ff08 (rfcomm_ioctl_mutex){+.+.}-{4:4}, at: rfcomm_create_dev net/bluetooth/rfcomm/tty.c:484 [inline] #0: ffffffff8f47ff08 (rfcomm_ioctl_mutex){+.+.}-{4:4}, at: rfcomm_dev_ioctl+0x232/0x1d40 net/bluetooth/rfcomm/tty.c:584 #1: ffff88807f6c4078 ( &hdev->lock ){+.+.}-{4:4} , at: rfcomm_reparent_device+0x4a/0x450 net/bluetooth/rfcomm/tty.c:187 1 lock held by syz.5.2954/15397: #0: ffffffff8f47ff08 ( rfcomm_ioctl_mutex ){+.+.}-{4:4} , at: rfcomm_create_dev net/bluetooth/rfcomm/tty.c:484 [inline] , at: rfcomm_dev_ioctl+0x232/0x1d40 net/bluetooth/rfcomm/tty.c:584 4 locks held by syz-executor/15476: #0: ffff8880588ecd80 (&hdev->req_lock ){+.+.}-{4:4} , at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] , at: hci_unregister_dev+0x1fe/0x500 net/bluetooth/hci_core.c:2678 #1: ffff8880588ec078 ( &hdev->lock ){+.+.}-{4:4} , at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5213 #2: ffffffff8f45a208 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2065 [inline] (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2534 #3: ffff88807ce2c338 ( &conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1761 4 locks held by syz-executor/15488: #0: ffff88802ef0e420 ( sb_writers #7 ){.+.+}-{0:0} , at: file_start_write include/linux/fs.h:3041 [inline] , at: vfs_write+0x211/0xa90 fs/read_write.c:680 #1: ffff88807b277488 ( &of->mutex ){+.+.}-{4:4} , at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325 #2: ffff88814539db48 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326 #3: ffffffff8eb94828 ( nsim_bus_dev_list_lock ){+.+.}-{4:4} , at: new_device_store+0x12c/0x6f0 drivers/net/netdevsim/bus.c:166 7 locks held by syz-executor/15492: #0: ffff88802ef0e420 ( sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:680 #1: ffff88805a756488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325 #2: ffff88814539dc38 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326 #3: ffffffff8eb94828 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216 #4: ffff888079e020e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #4: ffff888079e020e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #4: ffff888079e020e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x7c0 drivers/base/dd.c:1292 #5: ffff888079e01250 (&devlink->lock_key#23){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1675 #6: ffffffff8df41200 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3774 1 lock held by syz-executor/15530: #0: ffffffff8f2f4848 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f2f4848 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f2f4848 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4064 3 locks held by syz-executor/15541: #0: ffff888050344d80 ( &hdev->req_lock ){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] ){+.+.}-{4:4}, at: hci_unregister_dev+0x1fe/0x500 net/bluetooth/hci_core.c:2678 #1: ffff888050344078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5213 #2: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #2: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc5-syzkaller-00163-g09db7a4d287d #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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 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: 5909 Comm: kworker/1:7 Not tainted 6.15.0-rc5-syzkaller-00163-g09db7a4d287d #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events hidp_session_dev_work RIP: 0010:__sanitizer_cov_trace_cmp4+0x0/0x90 kernel/kcov.c:287 Code: 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 cc cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 14 25 08 40 75 92 65 8b 0d 08 6e RSP: 0018:ffffc900049e6d18 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 1ffffffff3369798 RCX: ffff88801dfe3c00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900049e6ed0 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200093cd80 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff99b4bcc0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881261cc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c0a2009000 CR3: 000000000dd36000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __uart_port_using_nbcon include/linux/serial_core.h:640 [inline] __uart_port_nbcon_acquire include/linux/serial_core.h:672 [inline] uart_port_lock_irqsave include/linux/serial_core.h:716 [inline] serial8250_console_write+0x375/0x1ba0 drivers/tty/serial/8250/8250_port.c:3415 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x725/0xc40 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xc4/0x270 kernel/printk/printk.c:3325 vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450 dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4917 dev_printk_emit+0xe0/0x130 drivers/base/core.c:4928 _dev_warn+0x10a/0x160 drivers/base/core.c:4984 hid_parser_main+0x8b8/0xc40 drivers/hid/hid-core.c:-1 hid_open_report+0x858/0xee0 drivers/hid/hid-core.c:1328 hid_parse include/linux/hid.h:1126 [inline] hid_generic_probe+0x3d/0x90 drivers/hid/hid-generic.c:66 __hid_device_probe drivers/hid/hid-core.c:2717 [inline] hid_device_probe+0x397/0x710 drivers/hid/hid-core.c:2754 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26a/0x9a0 drivers/base/dd.c:657 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:799 driver_probe_device+0x4f/0x430 drivers/base/dd.c:829 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:957 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1029 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3692 hid_add_device+0x398/0x540 drivers/hid/hid-core.c:2900 hidp_session_dev_add net/bluetooth/hidp/core.c:856 [inline] hidp_session_dev_work+0x45/0x160 net/bluetooth/hidp/core.c:895 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245