INFO: task khidpd_10cf05df:8488 blocked for more than 143 seconds. Not tainted 6.16.0-rc3-syzkaller-00136-g561aa0e22b70 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:khidpd_10cf05df state:D stack:29080 pid:8488 tgid:8488 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 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:4246 __cancel_work_sync+0xbe/0x110 kernel/workqueue.c:4366 hidp_session_remove+0x62/0x260 net/bluetooth/hidp/core.c:1169 l2cap_unregister_user+0x18b/0x1b0 net/bluetooth/l2cap_core.c:1734 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 INFO: task syz.4.891:8854 blocked for more than 144 seconds. Not tainted 6.16.0-rc3-syzkaller-00136-g561aa0e22b70 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.891 state:D stack:25352 pid:8854 tgid:8852 ppid:5832 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526 hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 hidp_verify_sockets net/bluetooth/hidp/core.c:1336 [inline] hidp_connection_add+0x21e/0x1a50 net/bluetooth/hidp/core.c:1356 do_hidp_sock_ioctl net/bluetooth/hidp/sock.c:81 [inline] hidp_sock_ioctl+0x36c/0x560 net/bluetooth/hidp/sock.c:128 sock_do_ioctl+0xdc/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:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 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: 0033:0x7fcb8758e929 RSP: 002b:00007fcb883d6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fcb877b5fa0 RCX: 00007fcb8758e929 RDX: 0000200000000340 RSI: 00000000400448c8 RDI: 0000000000000010 RBP: 00007fcb87610b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fcb877b5fa0 R15: 00007ffc0c999c28 INFO: task syz.4.891:8855 blocked for more than 145 seconds. Not tainted 6.16.0-rc3-syzkaller-00136-g561aa0e22b70 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.891 state:D stack:25352 pid:8855 tgid:8852 ppid:5832 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526 hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 hidp_verify_sockets net/bluetooth/hidp/core.c:1336 [inline] hidp_connection_add+0x21e/0x1a50 net/bluetooth/hidp/core.c:1356 do_hidp_sock_ioctl net/bluetooth/hidp/sock.c:81 [inline] hidp_sock_ioctl+0x36c/0x560 net/bluetooth/hidp/sock.c:128 sock_do_ioctl+0xdc/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:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 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: 0033:0x7fcb8758e929 RSP: 002b:00007fcb883b5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fcb877b6080 RCX: 00007fcb8758e929 RDX: 0000200000000340 RSI: 00000000400448c8 RDI: 0000000000000010 RBP: 00007fcb87610b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fcb877b6080 R15: 00007ffc0c999c28 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 2 locks held by kworker/u8:7/4188: #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: ffffc9000cd27bc0 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000cd27bc0 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 2 locks held by getty/5590: #0: ffff8880349e90a0 (&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 3 locks held by kworker/u8:8/6198: #0: ffff88802fd14948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88802fd14948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc9000b2afbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000b2afbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8f50ff48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f50ff48 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4198 8 locks held by kworker/1:11/8209: 2 locks held by khidpd_10cf05df/8488: #0: ffff8880312fc0b8 (&hdev->lock){+.+.}-{4:4}, at: l2cap_unregister_user+0x6a/0x1b0 net/bluetooth/l2cap_core.c:1728 #1: ffffffff8f6a10f0 (hidp_session_sem){++++}-{4:4}, at: hidp_session_remove+0x2c/0x260 net/bluetooth/hidp/core.c:1165 1 lock held by syz.4.891/8854: #0: ffffffff8f6a10f0 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.4.891/8855: #0: ffffffff8f6a10f0 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.0.1004/9312: #0: ffffffff8f6a10f0 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.0.1004/9313: #0: ffffffff8f6a10f0 ( hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.2.1123/9923: #0: ffffffff8f6a10f0 ( hidp_session_sem){++++}-{4:4}, at: hidp_get_connlist+0x97/0x2b0 net/bluetooth/hidp/core.c:1423 1 lock held by syz.6.1302/10877: #0: ffffffff8f6a10f0 ( hidp_session_sem ){++++}-{4:4}, at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.6.1302/10883: #0: ffffffff8f6a10f0 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz.7.1385/11301: #0: ffffffff8f6a10f0 (hidp_session_sem){++++}-{4:4}, at: hidp_session_find+0x1a/0x100 net/bluetooth/hidp/core.c:1026 1 lock held by syz-executor/11610: #0: ffffffff8f50ff48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f50ff48 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x5b7/0xd20 net/ipv6/addrconf.c:5031 1 lock held by syz-executor/11628: #0: ffffffff8f50ff48 (rtnl_mutex ){+.+.}-{4:4} , at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] , at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:979 4 locks held by syz.8.1482/11915: #0: ffffffff8f503350 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:570 #1: ffffffff8f50ff48 (rtnl_mutex){+.+.}-{4:4}, at: caif_exit_net+0x6a/0x4a0 net/caif/caif_dev.c:528 #2: ffff88804d077880 (&caifn->caifdevs.lock){+.+.}-{4:4}, at: caif_exit_net+0x7d/0x4a0 net/caif/caif_dev.c:529 #3: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #3: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc3-syzkaller-00136-g561aa0e22b70 #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:307 [inline] watchdog+0xfee/0x1030 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: 11610 Comm: syz-executor Not tainted 6.16.0-rc3-syzkaller-00136-g561aa0e22b70 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:409 Code: e8 de 08 79 fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 7f 8c dc fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 da 4c 22 06 cc 44 89 f9 80 e1 07 RSP: 0018:ffffc9000b6363d0 EFLAGS: 00000002 RAX: 1ffffffff33b9200 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020 RBP: ffffffff99dc99f0 R08: ffff8880247a0237 R09: 1ffff110048f4046 R10: dffffc0000000000 R11: ffffffff85474540 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff99dc9760 R15: 0000000000000000 FS: 00005555790d0500(0000) GS:ffff888125d50000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7889940e9c CR3: 000000005ec76000 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+0x1a1/0x2f0 drivers/tty/serial/8250/8250_port.c:2094 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3348 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3371 [inline] serial8250_console_write+0x134c/0x1ba0 drivers/tty/serial/8250/8250_port.c:3456 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x728/0xc40 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 _printk+0xcf/0x120 kernel/printk/printk.c:2475 netdev_info+0x10a/0x160 net/core/dev.c:12564 __dev_set_promiscuity+0x307/0x740 net/core/dev.c:9270 __dev_set_rx_mode+0x17c/0x260 net/core/dev.c:-1 dev_uc_add+0xc8/0x120 net/core/dev_addr_lists.c:693 macvlan_open+0x446/0x8e0 drivers/net/macvlan.c:647 __dev_open+0x46d/0x880 net/core/dev.c:1683 __dev_change_flags+0x1ea/0x6d0 net/core/dev.c:9458 netif_change_flags+0x88/0x1a0 net/core/dev.c:9521 do_setlink+0xc55/0x41c0 net/core/rtnetlink.c:3141 rtnl_changelink net/core/rtnetlink.c:3759 [inline] __rtnl_newlink net/core/rtnetlink.c:3918 [inline] rtnl_newlink+0x160b/0x1c70 net/core/rtnetlink.c:4055 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6944 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x75b/0x8d0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:727 __sys_sendto+0x3bd/0x520 net/socket.c:2180 __do_sys_sendto net/socket.c:2187 [inline] __se_sys_sendto net/socket.c:2183 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2183 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: 0033:0x7f1e39f907bc Code: 2a 5f 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5f 02 00 48 8b RSP: 002b:00007ffdc2f17bc0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f1e3ace4620 RCX: 00007f1e39f907bc RDX: 000000000000002c RSI: 00007f1e3ace4670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffdc2f17c14 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f1e3ace4670 R15: 0000000000000000