INFO: task syz-executor:23927 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:25752 pid:23927 tgid:23927 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f9/0x5500 kernel/sched/core.c:7197 __schedule_loop kernel/sched/core.c:7276 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7572 rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1667 __rt_mutex_slowlock kernel/locking/rtmutex.c:1744 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1784 [inline] rt_mutex_slowlock+0x2dc/0x780 kernel/locking/rtmutex.c:1824 __rt_mutex_lock kernel/locking/rtmutex.c:1839 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:541 [inline] mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:559 rtnl_net_lock include/linux/rtnetlink.h:130 [inline] inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6996 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2551 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x780/0x920 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1895 sock_sendmsg_nosec+0x112/0x150 net/socket.c:797 __sock_sendmsg net/socket.c:812 [inline] __sys_sendto+0x402/0x590 net/socket.c:2280 __do_sys_sendto net/socket.c:2287 [inline] __se_sys_sendto net/socket.c:2283 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2283 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f79ed4dd60e RSP: 002b:00007ffe05ee6e48 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555590ea3500 RCX: 00007f79ed4dd60e RDX: 0000000000000028 RSI: 00007f79ee2c4670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffe05ee6ec4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f79ee2c4670 R15: 0000000000000000 Showing all locks held in the system: 5 locks held by ktimers/1/30: #0: ffffffff8e05f380 (local_bh){.+.+}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163 #1: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163 #2: ffff8880b8728478 (&base->softirq_expiry_lock){+...}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #2: ffff8880b8728478 (&base->softirq_expiry_lock){+...}-{3:3}, at: hrtimer_cpu_base_lock_expiry kernel/time/hrtimer.c:1650 [inline] #2: ffff8880b8728478 (&base->softirq_expiry_lock){+...}-{3:3}, at: hrtimer_run_softirq+0x7f/0x260 kernel/time/hrtimer.c:2109 #3: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #3: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #3: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #3: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 #4: ffff888029a51288 (_T->lock){....}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:2036 [inline] #4: ffff888029a51288 (_T->lock){....}-{2:2}, at: __hrtimer_run_queues+0x4b1/0xb10 kernel/time/hrtimer.c:2096 1 lock held by khungtaskd/38: #0: ffffffff8e1c8240 (rcu_read_lock){...[ 2245.076035][ T38] #0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e1c8240 (rcu_read_lock){...[ 2245.076035][ T38] #0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e1c8240 (rcu_read_lock){...[ 2245.076035][ T38] #0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777 3 locks held by kworker/u8:8/1020: #0: ffff88813fe4c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3281 #1: ffffc9000529fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3282 #2: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313 2 locks held by getty/5365: #0: ffff8880362e20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211 4 locks held by kworker/u9:2/5007: #0: ffff88802a8eb938 ((wq_completion)hci9#2){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3281 #1: ffffc9001c097c40 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3282 #2: ffff8880587100b0 (&hdev->lock){+.+.}-{4:4}, at: le_conn_complete_evt+0xa5/0x16b0 net/bluetooth/hci_event.c:5732 #3: ffffffff8f712f18 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm+0x2c/0x140 include/net/bluetooth/hci_core.h:2136 3 locks held by kworker/u8:6/13828: #0: ffff88802cfae138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3281 #1: ffffc900059afc40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3282 #2: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4746 4 locks held by kworker/u9:1/20881: #0: ffff88805aa3f138 ((wq_completion)hci8#2){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3281 #1: ffffc900075a7c40 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3282 #2: ffff8880456340b0 (&hdev->lock){+.+.}-{4:4}, at: le_conn_complete_evt+0xa5/0x16b0 net/bluetooth/hci_event.c:5732 #3: ffffffff8f712f18 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm+0x2c/0x140 include/net/bluetooth/hci_core.h:2136 1 lock held by syz.6.30465/22366: #0: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3438 2 locks held by syz-executor/22498: #0: ffff888046548f80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline] #0: ffff888046548f80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716 #1: ffff8880465480b0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5356 3 locks held by syz-executor/22670: #0: ffff88804f014f80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline] (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716 #1: ffff88804f0140b0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5356 #2: ffffffff8f712f18 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline] #2: ffffffff8f712f18 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2734 3 locks held by kworker/0:0/22946: #0: ffff88813fe0f938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3281 #1: ffffc9000421fc40 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3282 #2: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 3 locks held by syz-executor/23752: #0: ffff888045600f80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline] #0: ffff888045600f80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716 #1: ffff8880456000b0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5356 #2: ffffffff8f712f18 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline] #2: ffffffff8f712f18 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2734 1 lock held by syz-executor/23927: #0: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 1 lock held by syz-executor/25118: #0: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 1 lock held by syz-executor/25245: #0: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 1 lock held by syz-executor/25264: #0: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 6 locks held by kworker/u9:4/25268: #0: ffff88802adb2938 ((wq_completion)hci6){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3281 #1: ffffc90005a1fc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3282 #2: ffff88805c0f4f80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d3/0x400 net/bluetooth/hci_sync.c:331 #3: ffff88805c0f40b0 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0xa6f/0x1190 net/bluetooth/hci_sync.c:5744 #4: ffffffff8f712f18 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2136 [inline] #4: ffffffff8f712f18 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x165/0x340 net/bluetooth/hci_conn.c:1409 #5: ffff8880294c2b70 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x92/0x570 net/bluetooth/l2cap_core.c:1777 1 lock held by syz-executor/25278: #0: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f5927b8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978 1 lock held by dhcpcd/25296: #0: ffff88803aae2358 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline] #0: ffff88803aae2358 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe70 net/packet/af_packet.c:3204 1 lock held by dhcpcd/25297: #0: ffff888068df4358 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline] #0: ffff888068df4358 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe70 net/packet/af_packet.c:3204 1 lock held by dhcpcd/25298: #0: ffff88802e014358 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline] #0: ffff88802e014358 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe70 net/packet/af_packet.c:3204 1 lock held by dhcpcd/25299: #0: ffff88802d7e0358 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline] #0: ffff88802d7e0358 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe70 net/packet/af_packet.c:3204 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 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: 30 Comm: ktimers/1 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:separate_irq_context kernel/locking/lockdep.c:4699 [inline] RIP: 0010:__lock_acquire+0x721/0x2d10 kernel/locking/lockdep.c:5223 Code: ff 0f 94 c1 08 c1 0f 84 87 20 00 00 49 89 5d 00 45 8b be f0 0b 00 00 4d 85 ff 0f 84 8e 00 00 00 41 83 ff 31 0f 83 ea 23 00 00 <4b> 8d 04 bf 4d 89 ec 41 8b 6d 20 48 8b 4c 24 20 8b 44 c1 f8 31 e8 RSP: 0018:ffffc90000a4f7c0 EFLAGS: 00000087 RAX: 000000000000003b RBX: 3e8e677205b53e66 RCX: ffffffff933e81a8 RDX: 0000000000000008 RSI: ffff88801decab80 RDI: ffff88801dec9ec0 RBP: 0000000000000000 R08: ffffffff8b35f947 R09: ffff888029a51288 R10: dffffc0000000000 R11: fffffbfff1f59a7f R12: 0000000000000003 R13: ffff88801decab80 R14: ffff88801dec9ec0 R15: 0000000000000005 FS: 0000000000000000(0000) GS:ffff888125dc7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055ae1bd50ab0 CR3: 0000000037e40000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5870 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166 rtlock_slowlock kernel/locking/rtmutex.c:1918 [inline] rtlock_lock kernel/locking/spinlock_rt.c:43 [inline] __rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline] rt_spin_lock+0x157/0x400 kernel/locking/spinlock_rt.c:57 spin_lock include/linux/spinlock_rt.h:45 [inline] xfrm_timer_handler+0xa3/0x9c0 net/xfrm/xfrm_state.c:648 __run_hrtimer kernel/time/hrtimer.c:2032 [inline] __hrtimer_run_queues+0x405/0xb10 kernel/time/hrtimer.c:2096 hrtimer_run_softirq+0x18f/0x260 kernel/time/hrtimer.c:2113 handle_softirqs+0x1de/0x6d0 kernel/softirq.c:626 __do_softirq kernel/softirq.c:660 [inline] run_ktimerd+0x69/0x100 kernel/softirq.c:1155 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245