INFO: task syz.2.1166:10937 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.2.1166 state:D stack:28232 pid:10937 tgid:10932 ppid:5820 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0xfee/0x6120 kernel/sched/core.c:6908 __schedule_loop kernel/sched/core.c:6990 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7005 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7062 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 nfsd_nl_listener_set_doit+0xd5/0x1a80 fs/nfsd/nfsctl.c:1893 genl_family_rcv_msg_doit+0x214/0x300 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x560/0x800 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa54/0xc30 net/socket.c:2592 ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646 __sys_sendmsg+0x170/0x220 net/socket.c:2678 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7faf1979c799 RSP: 002b:00007faf1a6ab028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007faf19a16090 RCX: 00007faf1979c799 RDX: 00000000200048d0 RSI: 0000200000000180 RDI: 0000000000000003 RBP: 00007faf19832bd9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007faf19a16128 R14: 00007faf19a16090 R15: 00007ffe296fadf8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e7e9220 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e7e9220 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e7e9220 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 4 locks held by kworker/1:1/46: #0: ffff888036f59948 ((wq_completion)wg-kex-wg2#6){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90000b67d08 ((work_completion)(&({ do { const void __seg_gs *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof_unqual__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffff8880771cd348 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_response+0x22b/0x950 drivers/net/wireguard/noise.c:742 #3: ffff88805ef10d20 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_response+0x2f8/0x950 drivers/net/wireguard/noise.c:753 4 locks held by kworker/R-bat_e/3407: 2 locks held by getty/5580: #0: ffff888037c410a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:4/5863: 3 locks held by kworker/1:3/5877: #0: ffff88813fe62148 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc900042f7d08 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffffffff90613c68 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x91/0x11d0 net/wireless/reg.c:2462 3 locks held by kworker/0:6/5939: 5 locks held by kworker/u10:0/6999: #0: ffff88801c6ae948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90003af7d08 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffffffff905fb330 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:675 #3: ffffffff90613c68 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0x90/0xc60 net/core/dev.c:13053 #4: ffffffff8e7f4e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311 4 locks held by kworker/u10:1/7002: 3 locks held by kworker/u10:2/7003: 6 locks held by kworker/u11:1/7005: #0: ffff888077d12948 ((wq_completion)hci4){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc9000efafd08 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffff888063e58ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x18a/0x470 net/bluetooth/hci_sync.c:331 #3: ffff888063e580c0 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x141/0xb20 net/bluetooth/hci_sync.c:5734 #4: ffffffff908abc68 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2136 [inline] #4: ffffffff908abc68 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x119/0x360 net/bluetooth/hci_conn.c:1342 #5: ffff88805c3a82f8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x80/0x770 net/bluetooth/l2cap_core.c:1755 3 locks held by kworker/u10:3/7006: #0: ffff888032c92948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc90003d57d08 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffffffff90613c68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff90613c68 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4738 3 locks held by kworker/u10:4/7027: 3 locks held by kworker/u10:5/7028: 3 locks held by kworker/u10:6/7234: 2 locks held by syz.2.1166/10933: #0: ffffffff906bfdf0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff8ec59508 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1a80 fs/nfsd/nfsctl.c:1893 2 locks held by syz.2.1166/10937: #0: ffffffff906bfdf0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff8ec59508 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1a80 fs/nfsd/nfsctl.c:1893 2 locks held by syz.3.1288/11429: #0: ffff88803516e0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88803516e0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88803516e0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super fs/super.c:508 [inline] #0: ffff88803516e0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505 #1: ffffffff8ec59508 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:576 3 locks held by kworker/u10:7/11697: 3 locks held by kworker/u10:8/11711: 5 locks held by kworker/u10:9/11712: 2 locks held by kworker/u10:10/11718: 4 locks held by kworker/u10:11/11719: 4 locks held by kworker/u10:12/11720: 4 locks held by kworker/u10:13/11721: 2 locks held by kworker/u10:14/11722: 4 locks held by kworker/u10:15/11723: 4 locks held by kworker/u10:16/11724: 3 locks held by kworker/u10:17/11725: 2 locks held by kworker/u10:18/11728: 2 locks held by syz-executor/11730: #0: ffff888036e90420 (sb_writers#4){.+.+}-{0:0}, at: filename_create+0x10d/0x400 fs/namei.c:4915 #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline] #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2923 [inline] #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2934 [inline] #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x1c0/0x400 fs/namei.c:4922 1 lock held by dhcpcd/11731: #0: ffff888063e56260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline] #0: ffff888063e56260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3197 2 locks held by dhcpcd/11732: #0: ffff888022f54260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline] #0: ffff888022f54260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3197 #1: ffffffff8e7f4e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 1 lock held by dhcpcd/11733: #0: ffff888076fbc260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline] #0: ffff888076fbc260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3197 1 lock held by dhcpcd/11734: #0: ffff888076fbe260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline] #0: ffff888076fbe260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3197 1 lock held by dhcpcd/11735: #0: ffff888077170260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline] #0: ffff888077170260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3197 2 locks held by syz-executor/11736: #0: ffff888036e90420 (sb_writers#4){.+.+}-{0:0}, at: filename_create+0x10d/0x400 fs/namei.c:4915 #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline] #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2923 [inline] #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2934 [inline] #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x1c0/0x400 fs/namei.c:4922 1 lock held by dhcpcd/11738: #0: ffff8880774a0260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline] #0: ffff8880774a0260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2c/0xf50 net/packet/af_packet.c:3197 2 locks held by syz-executor/11739: #0: ffff888036e90420 (sb_writers#4){.+.+}-{0:0}, at: filename_create+0x10d/0x400 fs/namei.c:4915 #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline] #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2923 [inline] #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2934 [inline] #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x1c0/0x400 fs/namei.c:4922 2 locks held by syz-executor/11740: #0: ffff888036e90420 (sb_writers#4){.+.+}-{0:0}, at: filename_create+0x10d/0x400 fs/namei.c:4915 #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline] #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2923 [inline] #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2934 [inline] #1: ffff888078d163d0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x1c0/0x400 fs/namei.c:4922 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xd25/0x1050 kernel/hung_task.c:515 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 3407 Comm: kworker/R-bat_e Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: bat_events batadv_tt_purge RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x35/0x70 kernel/kcov.c:217 Code: 48 8b 34 24 65 48 8b 15 61 30 05 12 a9 00 01 ff 00 74 1b f6 c4 01 74 07 a9 00 00 ff 00 74 05 e9 11 7c 88 09 8b 82 94 16 00 00 <85> c0 74 f1 8b 82 70 16 00 00 83 f8 02 75 e6 48 8b 8a 78 16 00 00 RSP: 0018:ffffc900000069e0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff88803e45a640 RCX: ffffffff895f3f84 RDX: ffff88803378db80 RSI: ffffffff86a93381 RDI: ffff88803e45a640 RBP: ffff88804a58c000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88805e0fe100 R13: dffffc0000000000 R14: ffff88803e45a6b0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88812434c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2a006899a0 CR3: 0000000034830000 CR4: 00000000003526f0 Call Trace: veth_xmit+0x21/0xe90 drivers/net/veth.c:353 __netdev_start_xmit include/linux/netdevice.h:5275 [inline] netdev_start_xmit include/linux/netdevice.h:5284 [inline] xmit_one net/core/dev.c:3871 [inline] dev_hard_start_xmit+0x121/0x7d0 net/core/dev.c:3887 __dev_queue_xmit+0x32c1/0x4800 net/core/dev.c:4840 dev_queue_xmit include/linux/netdevice.h:3384 [inline] br_dev_queue_push_xmit+0x360/0x550 net/bridge/br_forward.c:53 br_nf_dev_queue_xmit+0x741/0x2a20 net/bridge/br_netfilter_hooks.c:920 NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] br_nf_post_routing+0xcbb/0x16a0 net/bridge/br_netfilter_hooks.c:966 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xbf/0x220 net/netfilter/core.c:623 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK include/linux/netfilter.h:316 [inline] br_forward_finish+0x261/0x4d0 net/bridge/br_forward.c:66 br_nf_hook_thresh+0x30d/0x420 net/bridge/br_netfilter_hooks.c:1167 br_nf_forward_finish+0x693/0xb30 net/bridge/br_netfilter_hooks.c:662 NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] br_nf_forward_ip.part.0+0x61e/0x820 net/bridge/br_netfilter_hooks.c:716 br_nf_forward_ip net/bridge/br_netfilter_hooks.c:676 [inline] br_nf_forward+0xfe5/0x19f0 net/bridge/br_netfilter_hooks.c:773 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xbf/0x220 net/netfilter/core.c:623 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK include/linux/netfilter.h:316 [inline] __br_forward+0x2f6/0x970 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver+0xf0/0x180 net/bridge/br_forward.c:191 br_flood+0x193/0x650 net/bridge/br_forward.c:238 br_handle_frame_finish+0xf57/0x1f00 net/bridge/br_input.c:229 br_nf_hook_thresh+0x30d/0x420 net/bridge/br_netfilter_hooks.c:1167 br_nf_pre_routing_finish_ipv6+0x769/0xfb0 net/bridge/br_netfilter_ipv6.c:154 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x39c/0x8b0 net/bridge/br_netfilter_ipv6.c:184 br_nf_pre_routing+0x93b/0x1510 net/bridge/br_netfilter_hooks.c:508 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_bridge_pre net/bridge/br_input.c:291 [inline] br_handle_frame+0xcdd/0x1520 net/bridge/br_input.c:442 __netif_receive_skb_core.constprop.0+0x6c5/0x3550 net/core/dev.c:6054 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:6165 __netif_receive_skb+0x1f/0x120 net/core/dev.c:6280 process_backlog+0x37a/0x1580 net/core/dev.c:6631 __napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7695 napi_poll net/core/dev.c:7758 [inline] net_rx_action+0xa40/0xf20 net/core/dev.c:7910 handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622 do_softirq kernel/softirq.c:523 [inline] do_softirq+0xac/0xe0 kernel/softirq.c:510 __local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:450 spin_unlock_bh include/linux/spinlock.h:395 [inline] batadv_tt_global_purge net/batman-adv/translation-table.c:2250 [inline] batadv_tt_purge+0x25d/0xbd0 net/batman-adv/translation-table.c:3510 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] rescuer_thread+0x902/0x1490 kernel/workqueue.c:3582 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245