INFO: task syz.1.11076:13317 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.11076     state:D stack:25608 pid:13317 tgid:13315 ppid:7186   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5504 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7228
 __schedule_loop kernel/sched/core.c:7307 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7322
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7379
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 nfsd_nl_version_set_doit+0xcd/0x7a0 fs/nfsd/nfsctl.c:1798
 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:2556
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:775 [inline]
 __sock_sendmsg net/socket.c:790 [inline]
 ____sys_sendmsg+0x9b9/0xa20 net/socket.c:2684
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2738
 __sys_sendmsg net/socket.c:2770 [inline]
 __do_sys_sendmsg net/socket.c:2775 [inline]
 __se_sys_sendmsg net/socket.c:2773 [inline]
 __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2773
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7facf9b9ce59
RSP: 002b:00007facfaa81028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007facf9e15fa0 RCX: 00007facf9b9ce59
RDX: 0000000004008090 RSI: 0000200000000140 RDI: 0000000000000003
RBP: 00007facf9c32e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007facf9e16038 R14: 00007facf9e15fa0 R15: 00007fff42c4bb38
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 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+0xfd7/0x1030 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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_power_efficient neigh_periodic_work
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210
Code: 89 fb e8 23 00 00 00 48 8b 3d 34 da 61 0c 48 89 de 5b e9 33 f8 5f 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0d d8 49 74 11 65 8b 15 f9 49 74
RSP: 0018:ffffc90000006b30 EFLAGS: 00000293
RAX: ffffffff81b305a8 RBX: 001eed8dbf99c6e6 RCX: 0000000000000100
RDX: ffff88801da9dd00 RSI: 0000000000000018 RDI: 0000000000000040
RBP: 00000000000372ec R08: ffffffff903117f7 R09: 1ffffffff20622fe
R10: dffffc0000000000 R11: fffffbfff20622ff R12: 0000010ff0500756
R13: ffffffffffffffff R14: 0000000000000018 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff88812527c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564ccab52ee8 CR3: 0000000040f64000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 timekeeping_cycles_to_ns kernel/time/timekeeping.c:450 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:455 [inline]
 ktime_get+0x103/0x220 kernel/time/timekeeping.c:973
 cake_dequeue+0xa3/0x4f10 net/sched/sch_cake.c:2015
 dequeue_skb net/sched/sch_generic.c:322 [inline]
 qdisc_restart net/sched/sch_generic.c:427 [inline]
 __qdisc_run+0x24c/0x1620 net/sched/sch_generic.c:445
 qdisc_run include/net/pkt_sched.h:120 [inline]
 __dev_xmit_skb net/core/dev.c:4294 [inline]
 __dev_queue_xmit+0x1c00/0x37f0 net/core/dev.c:4833
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip6_output+0x337/0x540 net/ipv6/ip6_output.c:246
 synproxy_send_tcp_ipv6+0x549/0x700 net/netfilter/nf_synproxy_core.c:861
 synproxy_send_client_synack_ipv6+0x83f/0xcd0 net/netfilter/nf_synproxy_core.c:907
 nft_synproxy_eval_v6+0x37b/0x530 net/netfilter/nft_synproxy.c:91
 nft_synproxy_do_eval+0x3d1/0x550 net/netfilter/nft_synproxy.c:146
 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
 nft_do_chain+0x48d/0x1b10 net/netfilter/nf_tables_core.c:285
 nft_do_chain_inet+0x360/0x4b0 net/netfilter/nft_chain_filter.c:162
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619
 nf_hook include/linux/netfilter.h:273 [inline]
 NF_HOOK+0x21f/0x3c0 include/linux/netfilter.h:316
 ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:545
 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318
 __netif_receive_skb_one_core net/core/dev.c:6206 [inline]
 __netif_receive_skb net/core/dev.c:6319 [inline]
 process_backlog+0x774/0x1860 net/core/dev.c:6670
 __napi_poll+0xaa/0x330 net/core/dev.c:7729
 napi_poll net/core/dev.c:7792 [inline]
 net_rx_action+0x61d/0xf50 net/core/dev.c:7949
 handle_softirqs+0x225/0x840 kernel/softirq.c:622
 do_softirq+0x76/0xd0 kernel/softirq.c:523
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 neigh_periodic_work+0xc23/0xe40 net/core/neighbour.c:1035
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478
 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
 </TASK>