INFO: task syz.3.572:7939 blocked for more than 143 seconds. Not tainted 6.16.0-syzkaller-06600-g1dbf1d590d10 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.572 state:D stack:25544 pid:7939 tgid:7938 ppid:5847 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5351 [inline] __schedule+0x1737/0x4d30 kernel/sched/core.c:6954 __schedule_loop kernel/sched/core.c:7036 [inline] schedule+0x165/0x360 kernel/sched/core.c:7051 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:4246 __cancel_work_sync+0xbe/0x110 kernel/workqueue.c:4366 hidp_session_remove+0x62/0x260 net/bluetooth/hidp/core.c:1169 l2cap_unregister_user+0x18e/0x1b0 net/bluetooth/l2cap_core.c:1734 hidp_connection_del+0xb0/0x170 net/bluetooth/hidp/core.c:1409 do_hidp_sock_ioctl net/bluetooth/hidp/sock.c:97 [inline] hidp_sock_ioctl+0x317/0x560 net/bluetooth/hidp/sock.c:128 sock_do_ioctl+0xdc/0x300 net/socket.c:1238 sock_ioctl+0x576/0x790 net/socket.c:1359 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:598 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9b8cd8eb69 RSP: 002b:00007f9b8dc4a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f9b8cfb5fa0 RCX: 00007f9b8cd8eb69 RDX: 0000200000000000 RSI: 00000000400448c9 RDI: 0000000000000007 RBP: 00007f9b8ce11df1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9b8cfb5fa0 R15: 00007fffb786c998 INFO: task khidpd_16c05507:7945 blocked for more than 144 seconds. Not tainted 6.16.0-syzkaller-06600-g1dbf1d590d10 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:khidpd_16c05507 state:D stack:29096 pid:7945 tgid:7945 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5351 [inline] __schedule+0x1737/0x4d30 kernel/sched/core.c:6954 __schedule_loop kernel/sched/core.c:7036 [inline] schedule+0x165/0x360 kernel/sched/core.c:7051 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7108 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e3/0x1340 kernel/locking/mutex.c:760 l2cap_unregister_user+0x6a/0x1b0 net/bluetooth/l2cap_core.c:1728 hidp_session_thread+0x3c9/0x410 net/bluetooth/hidp/core.c:1304 kthread+0x70e/0x8a0 kernel/kthread.c:464 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 khungtaskd/31: #0: ffffffff8e13c4e0 ( 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: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 6 locks held by kworker/1:1/43: 2 locks held by getty/5598: #0: ffff88814d13f0a0 ( &tty->ldisc_sem ){++++}-{0:0} , at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 ( &ldata->atomic_read_lock ){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by udevd/5833: #0: ffff8881427c9358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 4 locks held by kworker/u8:7/5940: #0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc9000bd27bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000bd27bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8f509008 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 #3: ffffffff8e141f38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #3: ffffffff8e141f38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998 2 locks held by syz.3.572/7939: #0: ffff88802fc880b8 (&hdev->lock){+.+.}-{4:4}, at: l2cap_unregister_user+0x6a/0x1b0 net/bluetooth/l2cap_core.c:1728 #1: ffffffff8f696c70 (hidp_session_sem){++++}-{4:4}, at: hidp_session_remove+0x2c/0x260 net/bluetooth/hidp/core.c:1165 1 lock held by khidpd_16c05507/7945: #0: ffff88802fc880b8 (&hdev->lock){+.+.}-{4:4}, at: l2cap_unregister_user+0x6a/0x1b0 net/bluetooth/l2cap_core.c:1728 1 lock held by syz.2.661/8216: #0: ffff88802fc880b8 ( &hdev->lock ){+.+.}-{4:4} , at: l2cap_chan_connect+0x102/0xe30 net/bluetooth/l2cap_core.c:6980 1 lock held by syz.4.710/8354: #0: ffff88802fc880b8 ( &hdev->lock){+.+.}-{4:4}, at: l2cap_chan_connect+0x102/0xe30 net/bluetooth/l2cap_core.c:6980 1 lock held by syz.0.769/8605: #0: ffff88802fc880b8 (&hdev->lock){+.+.}-{4:4} , at: l2cap_chan_connect+0x102/0xe30 net/bluetooth/l2cap_core.c:6980 1 lock held by syz.5.943/9361: #0: ffffffff8f696c70 ( hidp_session_sem ){++++}-{4:4} , at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.1.1105/9931: #0: ffffffff8f696c70 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.8.1210/10292: #0: ffffffff8f696c70 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.8.1210/10296: #0: ffffffff8f696c70 ( hidp_session_sem ){++++}-{4:4} , at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.7.1242/10389: #0: ffffffff8f696c70 ( hidp_session_sem ){++++}-{4:4} , at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.7.1242/10391: #0: ffffffff8f696c70 ( hidp_session_sem ){++++}-{4:4} , at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.9.1570/11616: #0: ffffffff8f696c70 ( hidp_session_sem ){++++}-{4:4} , at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz-executor/12100: #0: ffffffff8f509008 ( rtnl_mutex ){+.+.}-{4:4} , at: rtnl_lock net/core/rtnetlink.c:80 [inline] , at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] , at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056 1 lock held by syz.3.1738/12191: #0: ffffffff8f696c70 ( hidp_session_sem ){++++}-{4:4} , at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.3.1738/12200: #0: ffffffff8f696c70 ( hidp_session_sem ){++++}-{4:4} , at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.4.1750/12234: #0: ffffffff8f509008 (rtnl_mutex){+.+.}-{4:4}, at: packet_mc_add+0x28/0xbb0 net/packet/af_packet.c:3736 1 lock held by syz.4.1750/12244: #0: ffffffff8f509008 (rtnl_mutex){+.+.}-{4:4}, at: packet_mc_add+0x28/0xbb0 net/packet/af_packet.c:3736 1 lock held by syz.4.1750/12245: #0: ffffffff8f509008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f509008 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6952 1 lock held by syz.4.1750/12246: #0: ffffffff8f509008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f509008 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6952 2 locks held by syz.4.1750/12247: #0: ffffffff8f56e570 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8f509008 (rtnl_mutex){+.+.}-{4:4}, at: nl80211_pre_doit+0x5f/0x930 net/wireless/nl80211.c:17363 1 lock held by syz.2.1751/12239: #0: ffffffff8f509008 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8f509008 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3433 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-syzkaller-06600-g1dbf1d590d10 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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+0xf93/0xfe0 kernel/hung_task.c:470 kthread+0x70e/0x8a0 kernel/kthread.c:464 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: 43 Comm: kworker/1:1 Not tainted 6.16.0-syzkaller-06600-g1dbf1d590d10 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: events hidp_session_dev_work RIP: 0010:debug_lockdep_rcu_enabled+0x2d/0x40 kernel/rcu/update.c:320 Code: fa 31 c0 83 3d 17 ad 30 04 00 74 1e 83 3d 3a dd 30 04 00 74 15 65 48 8b 0c 25 08 00 9a 92 31 c0 83 b9 ec 0a 00 00 00 0f 94 c0 0e dd 02 00 cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 RSP: 0018:ffffc90000a08bf0 EFLAGS: 00000046 RAX: 0000000000000001 RBX: ffff88801ce91480 RCX: ffff88801e685a00 RDX: 0000000000000000 RSI: ffffffff8be309e0 RDI: ffffffff8be309a0 RBP: 0000000000000000 R08: ffff88801b6e114f R09: 1ffff110036dc229 R10: dffffc0000000000 R11: ffffed10036dc22a R12: dffffc0000000000 R13: 0000000000000002 R14: ffffffff8db9ecd8 R15: ffff88802ee8c020 FS: 0000000000000000(0000) GS:ffff888125d80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555694ef5c8 CR3: 000000007f8d0000 CR4: 00000000003526f0 Call Trace: select_idle_cpu kernel/sched/fair.c:7602 [inline] select_idle_sibling kernel/sched/fair.c:7837 [inline] select_task_rq_fair+0x2385/0x3570 kernel/sched/fair.c:8536 select_task_rq kernel/sched/core.c:3601 [inline] try_to_wake_up+0x51e/0x1290 kernel/sched/core.c:4310 hrtimer_wakeup+0x4e/0x60 kernel/time/hrtimer.c:1997 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x52c/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+0x108/0x410 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 01 78 1f 00 41 89 df 4d 85 f6 48 8b 1c 24 75 07 e8 f0 77 1f 00 eb 06 e8 e9 77 1f 00 fb 48 c7 c7 80 07 13 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 f9 36 RSP: 0018:ffffc90000b37060 EFLAGS: 00000293 RAX: ffffffff81a038c7 RBX: ffffffff81a03784 RCX: ffff88801e685a00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e130780 RBP: ffffc90000b37170 R08: ffffffff8fa07bf7 R09: 1ffffffff1f40f7e R10: dffffc0000000000 R11: fffffbfff1f40f7f R12: dffffc0000000000 R13: 1ffff92000166e10 R14: 0000000000000200 R15: 000000000000003a dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4914 dev_printk_emit+0xe0/0x130 drivers/base/core.c:4925 _dev_warn+0x10a/0x160 drivers/base/core.c:4981 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:1133 [inline] hid_generic_probe+0x3d/0x90 drivers/hid/hid-generic.c:66 __hid_device_probe drivers/hid/hid-core.c:2736 [inline] hid_device_probe+0x3a0/0x710 drivers/hid/hid-core.c:2773 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0x9e0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3689 hid_add_device+0x398/0x540 drivers/hid/hid-core.c:2919 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+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245