INFO: task khidpd_0b570005:9330 blocked for more than 143 seconds. Not tainted 6.14.0-rc7-syzkaller-00182-gc7d82913d5f9 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:khidpd_0b570005 state:D stack:26936 pid:9330 tgid:9330 ppid:2 task_flags:0x208040 flags:0x00004000 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+0xb0/0x290 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+0x355/0x620 kernel/sched/completion.c:148 __flush_work+0xa47/0xc60 kernel/workqueue.c:4244 __cancel_work_sync+0xbc/0x110 kernel/workqueue.c:4364 hidp_session_remove+0x64/0x260 net/bluetooth/hidp/core.c:1169 l2cap_unregister_user+0x19c/0x1c0 net/bluetooth/l2cap_core.c:1733 hidp_session_thread+0x450/0x490 net/bluetooth/hidp/core.c:1304 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 INFO: task syz.4.1210:9957 blocked for more than 144 seconds. Not tainted 6.14.0-rc7-syzkaller-00182-gc7d82913d5f9 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.1210 state:D stack:26000 pid:9957 tgid:9956 ppid:5846 task_flags:0x400140 flags:0x00000004 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_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730 l2cap_chan_connect+0xff/0xeb0 net/bluetooth/l2cap_core.c:6919 l2cap_sock_connect+0x620/0x950 net/bluetooth/l2cap_sock.c:256 __sys_connect_file net/socket.c:2044 [inline] __sys_connect+0x288/0x2d0 net/socket.c:2063 __do_sys_connect net/socket.c:2069 [inline] __se_sys_connect net/socket.c:2066 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2066 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f183d98d169 RSP: 002b:00007f183b7f6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007f183dba5fa0 RCX: 00007f183d98d169 RDX: 000000000000000e RSI: 0000200000000080 RDI: 0000000000000004 RBP: 00007f183da0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f183dba5fa0 R15: 00007ffec6969b68 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746 3 locks held by kworker/u8:6/1146: 2 locks held by getty/5591: #0: ffff888031a070a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900033032f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211 3 locks held by kworker/u9:3/5839: #0: ffff888024c9b148 ((wq_completion)hci7){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888024c9b148 ((wq_completion)hci7){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc90004087c60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90004087c60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffff888052840d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1ec/0x400 net/bluetooth/hci_sync.c:331 3 locks held by kworker/u9:7/5851: #0: ffff88805088d148 ((wq_completion)hci8){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88805088d148 ((wq_completion)hci8){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc90004107c60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90004107c60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffff888034ed8d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1ec/0x400 net/bluetooth/hci_sync.c:331 4 locks held by kworker/0:18/6854: 3 locks held by kworker/1:11/6859: 2 locks held by khidpd_0b570005/9330: #0: ffff88807175c078 (&hdev->lock){+.+.}-{4:4}, at: l2cap_unregister_user+0x6a/0x1c0 net/bluetooth/l2cap_core.c:1727 #1: ffffffff900643f0 (hidp_session_sem){++++}-{4:4}, at: hidp_session_remove+0x2d/0x260 net/bluetooth/hidp/core.c:1165 1 lock held by syz.4.1210/9957: #0: ffff88807175c078 (&hdev->lock){+.+.}-{4:4}, at: l2cap_chan_connect+0xff/0xeb0 net/bluetooth/l2cap_core.c:6919 2 locks held by syz.2.1365/10462: #0: ffffffff9005daa8 (rfcomm_mutex){+.+.}-{4:4}, at: rfcomm_dlc_open+0xa4/0x10d0 net/bluetooth/rfcomm/core.c:429 #1: ffff88807175c078 (&hdev->lock){+.+.}-{4:4}, at: l2cap_chan_connect+0xff/0xeb0 net/bluetooth/l2cap_core.c:6919 1 lock held by syz.2.1365/10467: #0: ffffffff9005daa8 (rfcomm_mutex){+.+.}-{4:4}, at: rfcomm_dlc_close+0x3b/0x190 net/bluetooth/rfcomm/core.c:511 1 lock held by syz.3.1390/10547: #0: ffffffff9005daa8 (rfcomm_mutex){+.+.}-{4:4}, at: rfcomm_dlc_open+0xa4/0x10d0 net/bluetooth/rfcomm/core.c:429 1 lock held by syz.3.1390/10550: #0: ffffffff9005daa8 ( rfcomm_mutex){+.+.}-{4:4}, at: rfcomm_dlc_close+0x3b/0x190 net/bluetooth/rfcomm/core.c:511 1 lock held by syz.1.1400/10575: #0: ffff88807175c078 (&hdev->lock){+.+.}-{4:4}, at: l2cap_chan_connect+0xff/0xeb0 net/bluetooth/l2cap_core.c:6919 1 lock held by syz.1.1400/10578: #0: ffffffff900643f0 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1c/0x110 net/bluetooth/hidp/core.c:1026 2 locks held by syz.5.1472/10834: #0: ffffffff90061548 (rfcomm_ioctl_mutex){+.+.}-{4:4}, at: rfcomm_create_dev net/bluetooth/rfcomm/tty.c:484 [inline] #0: ffffffff90061548 (rfcomm_ioctl_mutex){+.+.}-{4:4}, at: rfcomm_dev_ioctl+0x236/0x22f0 net/bluetooth/rfcomm/tty.c:584 #1: ffffffff9005daa8 (rfcomm_mutex){+.+.}-{4:4}, at: rfcomm_dlc_exists+0x45/0x160 net/bluetooth/rfcomm/core.c:546 1 lock held by syz.0.1532/11111: #0: ffffffff900643f0 (hidp_session_sem ){++++}-{4:4}, at: hidp_session_find+0x1c/0x110 net/bluetooth/hidp/core.c:1026 1 lock held by syz.6.1575/11277: #0: ffffffff900643f0 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1c/0x110 net/bluetooth/hidp/core.c:1026 1 lock held by syz.4.1979/12704: #0: ffffffff9005daa8 (rfcomm_mutex){+.+.}-{4:4}, at: rfcomm_dlc_open+0xa4/0x10d0 net/bluetooth/rfcomm/core.c:429 1 lock held by syz.4.1979/12714: #0: ffffffff9005daa8 (rfcomm_mutex){+.+.}-{4:4}, at: rfcomm_dlc_close+0x3b/0x190 net/bluetooth/rfcomm/core.c:511 1 lock held by syz.2.2063/12973: #0: ffffffff900643f0 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1c/0x110 net/bluetooth/hidp/core.c:1026 1 lock held by syz.8.2105/13132: #0: ffffffff900643f0 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1c/0x110 net/bluetooth/hidp/core.c:1026 1 lock held by syz.9.2148/13288: #0: ffffffff9005daa8 (rfcomm_mutex){+.+.}-{4:4}, at: rfcomm_dlc_open+0xa4/0x10d0 net/bluetooth/rfcomm/core.c:429 1 lock held by syz.7.2189/13456: #0: ffffffff90061548 (rfcomm_ioctl_mutex){+.+.}-{4:4}, at: rfcomm_create_dev net/bluetooth/rfcomm/tty.c:484 [inline] #0: ffffffff90061548 (rfcomm_ioctl_mutex){+.+.}-{4:4}, at: rfcomm_dev_ioctl+0x236/0x22f0 net/bluetooth/rfcomm/tty.c:584 5 locks held by syz-executor/13458: #0: ffff888024b84d80 ( &hdev->req_lock ){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] ){+.+.}-{4:4}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2678 #1: ffff888024b84078 (&hdev->lock){+.+.}-{4:4} , at: hci_dev_close_sync+0x60d/0x1260 net/bluetooth/hci_sync.c:5185 #2: ffffffff9003b788 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2041 [inline] #2: ffffffff9003b788 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2698 #3: ffff88805ccc9338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x71/0x690 net/bluetooth/l2cap_core.c:1761 #4: ffffffff8eb3e8b8 (rcu_state.exp_mutex ){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:302 [inline] ){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x381/0x820 kernel/rcu/tree_exp.h:996 3 locks held by syz-executor/13580: #0: ffff88804ffacd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff88804ffacd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2678 #1: ffff88804ffac078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x60d/0x1260 net/bluetooth/hci_sync.c:5185 #2: ffffffff9003b788 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2041 [inline] #2: ffffffff9003b788 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2698 3 locks held by syz-executor/13596: #0: ffff88804a048d80 (&hdev->req_lock ){+.+.}-{4:4} , at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] , at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2678 #1: ffff88804a048078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x60d/0x1260 net/bluetooth/hci_sync.c:5185 #2: ffffffff9003b788 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2041 [inline] #2: ffffffff9003b788 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2698 3 locks held by syz-executor/13653: #0: ffff88805ce68d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff88805ce68d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2678 #1: ffff88805ce68078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x60d/0x1260 net/bluetooth/hci_sync.c:5185 #2: ffffffff9003b788 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2041 [inline] #2: ffffffff9003b788 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2698 1 lock held by syz.3.2243/13663: #0: ffffffff900643f0 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1c/0x110 net/bluetooth/hidp/core.c:1026 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc7-syzkaller-00182-gc7d82913d5f9 #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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6859 Comm: kworker/1:11 Not tainted 6.14.0-rc7-syzkaller-00182-gc7d82913d5f9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: events hidp_session_dev_work RIP: 0010:io_serial_in+0x76/0xb0 drivers/tty/serial/8250/8250_port.c:409 Code: 10 8b 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 81 ca a4 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:ffffc9001bcceb78 EFLAGS: 00000002 RAX: 1ffffffff3533200 RBX: ffffffff9a999100 RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020 RBP: 0000000000000000 R08: ffffffff85845566 R09: 1ffff11004a8a046 R10: dffffc0000000000 R11: ffffffff85845520 R12: 0000000000000020 R13: 1ffffffff3533272 R14: 00000000000003fd R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff4a6c5c440 CR3: 000000000e938000 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 dev_vprintk_emit+0x341/0x400 drivers/base/core.c:4891 dev_printk_emit+0xdd/0x120 drivers/base/core.c:4902 _dev_warn+0x122/0x170 drivers/base/core.c:4958 hid_parser_main+0x812/0xc00 drivers/hid/hid-core.c:660 hid_open_report+0xbd8/0x1580 drivers/hid/hid-core.c:1324 hid_parse include/linux/hid.h:1124 [inline] hid_generic_probe+0x3d/0x90 drivers/hid/hid-generic.c:66 __hid_device_probe drivers/hid/hid-core.c:2713 [inline] hid_device_probe+0x3bf/0x710 drivers/hid/hid-core.c:2750 really_probe+0x2b9/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830 __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:462 __device_attach+0x333/0x520 drivers/base/dd.c:1030 bus_probe_device+0x189/0x260 drivers/base/bus.c:537 device_add+0x856/0xbf0 drivers/base/core.c:3666 hid_add_device+0x3b6/0x520 drivers/hid/hid-core.c:2896 hidp_session_dev_add net/bluetooth/hidp/core.c:856 [inline] hidp_session_dev_work+0x46/0x160 net/bluetooth/hidp/core.c:895 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd30 kernel/workqueue.c:3400 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