Index: sys/net/if.c
===================================================================
--- sys/net/if.c	(revision 289450)
+++ sys/net/if.c	(working copy)
@@ -3315,7 +3315,7 @@ if_delmulti_locked(struct ifnet *ifp, struct ifmul
  * At this time we only support certain types of interfaces,
  * and we don't allow the length of the address to change.
  */
-int
+__noinline int
 if_setlladdr(struct ifnet *ifp, const u_char *lladdr, int len)
 {
 	struct sockaddr_dl *sdl;
Index: sys/net/if_lagg.c
===================================================================
--- sys/net/if_lagg.c	(revision 289450)
+++ sys/net/if_lagg.c	(working copy)
@@ -730,7 +754,7 @@ lagg_port_create(struct lagg_softc *sc, struct ifn
 	}
 
 	/* XXX Disallow non-ethernet interfaces (this should be any of 802) */
-	if (ifp->if_type != IFT_ETHER)
+	if (ifp->if_type != IFT_ETHER && ifp->if_type != IFT_L2VLAN)
 		return (EPROTONOSUPPORT);
 
 	/* Allow the first Ethernet member to define the MTU */
Index: sys/netinet/if_ether.c
===================================================================
--- sys/netinet/if_ether.c	(revision 289450)
+++ sys/netinet/if_ether.c	(working copy)
@@ -144,7 +144,9 @@ static void arp_check_update_lle(struct arphdr *ah
 static void arp_update_lle(struct arphdr *ah, struct ifnet *ifp,
     struct llentry *la);
 static void arp_mark_lle_reachable(struct llentry *la);
+static void arp_iflladdr(void *arg __unused, struct ifnet *ifp);
 
+static eventhandler_tag iflladdr_tag;
 
 static const struct netisr_handler arp_nh = {
 	.nh_name = "arp",
@@ -1163,10 +1165,35 @@ arp_ifinit2(struct ifnet *ifp, struct ifaddr *ifa,
 	ifa->ifa_rtrequest = NULL;
 }
 
+/*
+ * A handler for interface link layer address change event.
+ */
+static __noinline void
+arp_iflladdr(void *arg __unused, struct ifnet *ifp)
+{
+	struct ifaddr *ifa;
+
+	if ((ifp->if_flags & IFF_UP) == 0)
+		return;
+
+	return;
+
+	/*
+	 * Also send gratuitous ARPs to notify other nodes about
+	 * the address change.
+	 */
+	TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+		if (ifa->ifa_addr->sa_family == AF_INET)
+			arp_ifinit(ifp, ifa);
+	}
+}
+
 static void
 arp_init(void)
 {
 
 	netisr_register(&arp_nh);
+	iflladdr_tag = EVENTHANDLER_REGISTER(iflladdr_event,
+	    arp_iflladdr, NULL, EVENTHANDLER_PRI_ANY);
 }
 SYSINIT(arp, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, arp_init, 0);