--- zzzz-none-000/linux-4.4.271/net/ipv6/ndisc.c	2021-06-03 06:22:09.000000000 +0000
+++ hawkeye-5590-750/linux-4.4.271/net/ipv6/ndisc.c	2023-04-19 10:22:30.000000000 +0000
@@ -594,6 +594,7 @@
 
 	ndisc_send_skb(skb, daddr, saddr);
 }
+EXPORT_SYMBOL(ndisc_send_ns);
 
 void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr,
 		   const struct in6_addr *daddr)