INFO: task syz.1.1257:10463 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1257 state:D stack:26616 pid:10463 tgid:10455 ppid:5617 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5533 [inline] __schedule+0x17db/0x58f0 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7376 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7433 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x7c1/0x1550 kernel/locking/mutex.c:821 nfsd_nl_svc_export_set_reqs_doit+0x132/0x1480 fs/nfsd/export.c:1057 genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2579 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1338 [inline] netlink_unicast+0x8ef/0xa80 net/netlink/af_netlink.c:1364 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1923 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800 __sock_sendmsg net/socket.c:815 [inline] ____sys_sendmsg+0x54e/0x850 net/socket.c:2713 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2767 __sys_sendmsg net/socket.c:2799 [inline] __do_sys_sendmsg net/socket.c:2804 [inline] __se_sys_sendmsg net/socket.c:2802 [inline] __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2802 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7eff2a39e559 RSP: 002b:00007eff2b25a028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007eff2a626090 RCX: 00007eff2a39e559 RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000006 RBP: 00007eff2a435ab8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007eff2a626128 R14: 00007eff2a626090 R15: 00007ffe9d978078 Showing all locks held in the system: locks held by khungtaskd/31: 1, last CPU#0: #0: ffffffff8fd5c8e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8fd5c8e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8fd5c8e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871 locks held by kworker/u8:2/42: 2, on CPU#0: #0: ffff88801c0ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff88801c0ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff88801c0ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff88801c0ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc90000b27c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc90000b27c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc90000b27c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc90000b27c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 locks held by kworker/u8:6/595: 2, last CPU#0: #0: ffff88801c0ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff88801c0ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff88801c0ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff88801c0ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc9000408fc40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc9000408fc40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc9000408fc40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc9000408fc40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 locks held by kworker/u9:1/4932: 3, on CPU#0: #0: ffff888076bd3940 ((wq_completion)hci10){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff888076bd3940 ((wq_completion)hci10){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff888076bd3940 ((wq_completion)hci10){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff888076bd3940 ((wq_completion)hci10){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc900101ffc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc900101ffc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc900101ffc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc900101ffc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #2: ffff8880670b4ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x242/0x430 net/bluetooth/hci_sync.c:337 locks held by getty/5368: 2, on CPU#0: #0: ffff888036a500a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900032432e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211 locks held by syz.2.1163/10133: 2, on CPU#0: #0: ffffffff912c6888 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff9009f9a0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x53d/0x1ab0 fs/nfsd/nfsctl.c:2057 locks held by syz.1.1257/10463: 2, on CPU#0: #0: ffffffff912c6888 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff9009f9a0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_svc_export_set_reqs_doit+0x132/0x1480 fs/nfsd/export.c:1057 locks held by syz.4.1748/12575: 2, on CPU#0: #0: ffffffff912c6888 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff9009f9a0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_unlock_filesystem_doit+0x2af/0x410 fs/nfsd/nfsctl.c:2677 locks held by syz.7.2177/14351: 2, on CPU#0: #0: ffffffff912c6888 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff9009f9a0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1784 locks held by syz.0.2204/14429: 2, on CPU#1: #0: ffffffff912c6888 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff9009f9a0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_svc_export_set_reqs_doit+0x132/0x1480 fs/nfsd/export.c:1057 locks held by syz.0.2204/14430: 2, on CPU#1: #0: ffffffff912c6888 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff9009f9a0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_svc_export_set_reqs_doit+0x132/0x1480 fs/nfsd/export.c:1057 locks held by syz.5.2322/14934: 2, on CPU#1: #0: ffffffff912c6888 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217 #1: ffffffff9009f9a0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_set_doit+0xcd/0x7a0 fs/nfsd/nfsctl.c:1844 locks held by syz.8.2606/16170: 1, last CPU#0: #0: ffffffff8fd5c8e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8fd5c8e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8fd5c8e0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline] #0: ffffffff8fd5c8e0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495 locks held by syz.8.2606/16173: 3, last CPU#0: #0: ffff88804f479f00 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline] #0: ffff88804f479f00 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x7a/0x1f0 net/socket.c:734 #1: ffffffff912c48a8 ((netlink_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain+0x54/0x90 kernel/notifier.c:379 #2: ffffffff8fd5c8e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #2: ffffffff8fd5c8e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #2: ffffffff8fd5c8e0 (rcu_read_lock){....}-{1:3}, at: nl80211_netlink_notify+0x75/0x860 net/wireless/nl80211.c:23143 locks held by syz.8.2606/16176: 1, last CPU#0: #0: ffffffff904f2b38 (tomoyo_ss){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:198 [inline] #0: ffffffff904f2b38 (tomoyo_ss){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:305 [inline] #0: ffffffff904f2b38 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_read_lock security/tomoyo/common.h:1112 [inline] #0: ffffffff904f2b38 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_path_number_perm+0x219/0x5f0 security/tomoyo/file.c:727 locks held by dhcpcd/16184: 1, last CPU#0: #0: ffff88806926d900 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline] #0: ffff88806926d900 (&mm->mmap_lock){++++}-{4:4}, at: __vm_munmap+0x163/0x3e0 mm/vma.c:3412 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123 nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66 trigger_all_cpu_backtrace include/linux/nmi.h:164 [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+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x38b/0x480 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: 5739 Comm: kworker/1:6 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Workqueue: wg-crypt-wg2 wg_packet_tx_worker RIP: 0010:__bfs_next kernel/locking/lockdep.c:1743 [inline] RIP: 0010:__bfs kernel/locking/lockdep.c:1796 [inline] RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1904 [inline] RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2840 [inline] RIP: 0010:check_prev_add kernel/locking/lockdep.c:3213 [inline] RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3328 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:3952 [inline] RIP: 0010:__lock_acquire+0x186e/0x2de0 kernel/locking/lockdep.c:5288 Code: 00 48 89 05 a4 46 f9 15 48 8d 84 24 90 00 00 00 48 89 05 95 c6 f8 15 31 ff 45 31 ff 4d 85 ff 4c 8b 74 24 10 74 2e 49 8b 47 30 <48> 85 c0 74 25 48 8b 40 10 48 83 c0 30 49 8b 0f 48 89 8c 24 d8 00 RSP: 0000:ffffc90004d8f020 EFLAGS: 00000082 RAX: ffffffff98202e18 RBX: 00000000000003fd RCX: 000000000003ebdb RDX: 0000000000000008 RSI: ffff888027fe8cf0 RDI: 00000000000003fd RBP: 3bc0a1208c7e91da R08: ffffc90004d8efe8 R09: 0000000000000020 R10: 0000000000000003 R11: ffffffff81a3d8d0 R12: 0000000000000530 R13: ffffffff953d9340 R14: ffff888027fe8cf0 R15: ffffffff982424a8 FS: 0000000000000000(0000) GS:ffff888123bbf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a1325b5040 CR3: 0000000050048000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 seqcount_lockdep_reader_access+0x55/0x100 include/linux/seqlock.h:73 ktime_get+0x45/0x220 kernel/time/timekeeping.c:1002 clockevents_program_event+0x290/0x630 kernel/time/clockevents.c:363 hrtimer_rearm kernel/time/hrtimer.c:2176 [inline] __hrtimer_rearm_deferred+0x36c/0x4b0 kernel/time/hrtimer.c:2196 hrtimer_rearm_deferred_tif include/linux/hrtimer_rearm.h:58 [inline] hrtimer_rearm_deferred include/linux/hrtimer_rearm.h:67 [inline] irqentry_exit_to_kernel_mode_after_preempt include/linux/irq-entry-common.h:505 [inline] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:542 [inline] irqentry_exit+0x8d9/0x920 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:lock_acquire+0x232/0x350 kernel/locking/lockdep.c:5947 Code: ff ff ff e8 30 5d 45 0a f7 44 24 10 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 42 a7 f2 12 48 3b 44 24 50 75 33 fb 48 83 c4 58 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d f7 44 da RSP: 0000:ffffc90004d8f470 EFLAGS: 00000292 RAX: 9327fa8b5585e400 RBX: 0000000000000001 RCX: 8000000000000602 RDX: ffff888027fe8c28 RSI: ffffffff8e6f1e7e RDI: ffffffff8c6ddb80 RBP: ffff888027fe8000 R08: ffffc90004d8f398 R09: 0000000000000020 R10: dffffc0000000000 R11: ffffffff81a3c8d0 R12: ffff88807f0a0170 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000246 __raw_spin_lock include/linux/spinlock_api_smp.h:190 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:173 spin_lock include/linux/spinlock.h:347 [inline] __dev_xmit_skb net/core/dev.c:4315 [inline] __dev_queue_xmit+0xd56/0x3920 net/core/dev.c:4916 NF_HOOK_COND include/linux/netfilter.h:314 [inline] ip6_output+0x337/0x540 net/ipv6/ip6_output.c:248 ip6tunnel_xmit include/net/ip6_tunnel.h:174 [inline] udp_tunnel6_xmit_skb+0x6d9/0xd60 net/ipv6/ip6_udp_tunnel.c:112 send6+0x5ce/0x920 drivers/net/wireguard/socket.c:151 wg_socket_send_skb_to_peer+0x111/0x1d0 drivers/net/wireguard/socket.c:177 wg_packet_create_data_done drivers/net/wireguard/send.c:251 [inline] wg_packet_tx_worker+0x1c8/0x7e0 drivers/net/wireguard/send.c:276 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560 kthread+0x38b/0x480 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