diff --git a/sys/netinet6/nd6.c b/sys/netinet6/nd6.c
index 1ad03e8cf4b9..0784fa2165dd 100644
--- a/sys/netinet6/nd6.c
+++ b/sys/netinet6/nd6.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: nd6.c,v 1.216 2016/12/12 03:55:57 ozaki-r Exp $	*/
+/*	$NetBSD: nd6.c,v 1.217 2016/12/14 04:05:11 ozaki-r Exp $	*/
 /*	$KAME: nd6.c,v 1.279 2002/06/08 11:16:51 itojun Exp $	*/
 
 /*
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: nd6.c,v 1.216 2016/12/12 03:55:57 ozaki-r Exp $");
+__KERNEL_RCSID(0, "$NetBSD: nd6.c,v 1.217 2016/12/14 04:05:11 ozaki-r Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_net_mpsafe.h"
@@ -116,6 +116,7 @@ static void nd6_llinfo_timer(void *);
 static void nd6_timer(void *);
 static void nd6_timer_work(struct work *, void *);
 static void clear_llinfo_pqueue(struct llentry *);
+static struct nd_opt_hdr *nd6_option(union nd_opts *);
 
 static callout_t nd6_slowtimo_ch;
 static callout_t nd6_timer_ch;
@@ -259,7 +260,7 @@ nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts)
 /*
  * Take one ND option.
  */
-struct nd_opt_hdr *
+static struct nd_opt_hdr *
 nd6_option(union nd_opts *ndopts)
 {
 	struct nd_opt_hdr *nd_opt;
diff --git a/sys/netinet6/nd6.h b/sys/netinet6/nd6.h
index ebb323ceafe9..28fdba8de64e 100644
--- a/sys/netinet6/nd6.h
+++ b/sys/netinet6/nd6.h
@@ -1,4 +1,4 @@
-/*	$NetBSD: nd6.h,v 1.78 2016/12/12 03:14:01 ozaki-r Exp $	*/
+/*	$NetBSD: nd6.h,v 1.79 2016/12/14 04:05:11 ozaki-r Exp $	*/
 /*	$KAME: nd6.h,v 1.95 2002/06/08 11:31:06 itojun Exp $	*/
 
 /*
@@ -422,7 +422,6 @@ struct nd_ifinfo *nd6_ifattach(struct ifnet *);
 void nd6_ifdetach(struct ifnet *, struct in6_ifextra *);
 int nd6_is_addr_neighbor(const struct sockaddr_in6 *, struct ifnet *);
 void nd6_option_init(void *, int, union nd_opts *);
-struct nd_opt_hdr *nd6_option(union nd_opts *);
 int nd6_options(union nd_opts *);
 struct llentry *nd6_lookup(const struct in6_addr *, const struct ifnet *, bool);
 struct llentry *nd6_create(const struct in6_addr *, const struct ifnet *);
@@ -456,7 +455,6 @@ void nd6_ns_output(struct ifnet *, const struct in6_addr *,
 const void *nd6_ifptomac(const struct ifnet *);
 void nd6_dad_start(struct ifaddr *, int);
 void nd6_dad_stop(struct ifaddr *);
-void nd6_dad_duplicated(struct ifaddr *);
 
 /* nd6_rtr.c */
 void nd6_rs_input(struct mbuf *, int, int);
diff --git a/sys/netinet6/nd6_nbr.c b/sys/netinet6/nd6_nbr.c
index 0bdedf44e069..a36c31172772 100644
--- a/sys/netinet6/nd6_nbr.c
+++ b/sys/netinet6/nd6_nbr.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: nd6_nbr.c,v 1.132 2016/12/12 03:55:57 ozaki-r Exp $	*/
+/*	$NetBSD: nd6_nbr.c,v 1.133 2016/12/14 04:05:11 ozaki-r Exp $	*/
 /*	$KAME: nd6_nbr.c,v 1.61 2001/02/10 16:06:14 jinmei Exp $	*/
 
 /*
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: nd6_nbr.c,v 1.132 2016/12/12 03:55:57 ozaki-r Exp $");
+__KERNEL_RCSID(0, "$NetBSD: nd6_nbr.c,v 1.133 2016/12/14 04:05:11 ozaki-r Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_inet.h"
@@ -84,6 +84,7 @@ static void nd6_dad_timer(struct ifaddr *);
 static void nd6_dad_ns_output(struct dadq *, struct ifaddr *);
 static void nd6_dad_ns_input(struct ifaddr *);
 static void nd6_dad_na_input(struct ifaddr *);
+static void nd6_dad_duplicated(struct ifaddr *);
 
 static int dad_ignore_ns = 0;	/* ignore NS in DAD - specwise incorrect*/
 static int dad_maxtry = 15;	/* max # of *tries* to transmit DAD packet */
@@ -1335,7 +1336,7 @@ done:
 #endif
 }
 
-void
+static void
 nd6_dad_duplicated(struct ifaddr *ifa)
 {
 	struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa;