net: attach IPv4 and IPv6 stacks to an interface with EVENTHANDLER(9)

This change retires two historic relics: the if_afdata[] array and the
dom_ifattach/dom_ifdetach methods.

The if_afdata[] array is a relic of the era, when there was expectation
that many transport protocols will coexist with IP, e.g. IPX or NetAtalk.
The array hasn't had any members except AF_INET and AF_INET6 for over a
decade already. This change removes the array and just leaves two pointer
fields: if_inet and if_inet6.

The dom_ifattach/dom_ifdetach predates the EVENTHANDLER(9) framework and
was a good enough method to initialize protocol contexts back then.  Today
there is no good reason to treat IPv4 and IPv6 stacks differently to other
protocols/features that attach and detach from an interface.

The locking of if_afdata[] is a relic of SMPng times, when the system
startup and the interface attach was even more convoluted than before this
change, and we also had unloadable protocols that used a field in
if_afdata[].  Note that IPv4 and IPv6 are not unloadable.

Note that this change removes NET_EPOCH_WAIT() from the interface detach
sequence.  This may surface several new races associated with interface
removal.  I failed to hit any with consecutive test suite runs, though.
The expected general race scenario is that while struct ifnet is freed
with proper epoch_call(9) itself, some structures hanging off ifnet are
freed with direct free(9).  The proper fix is either make if_foo point at
some static "dead" structure providing SMP visibility of this store, or
free those structure with epoch_call(9).  All of these cases are planned
to be found and resolved during 16.0-CURRENT lifetime.

Reviewed by:		zlei, gallatin, melifaro
Differential Revision:	https://reviews.freebsd.org/D54089

28 files changed, 173 insertions, 258 deletions

diff --git a/sys/kern/uipc_debug.c b/sys/kern/uipc_debug.c
index df36ec75cb5f..f6b7b1899d02 100644
--- a/sys/kern/uipc_debug.c
+++ b/sys/kern/uipc_debug.c
@@ -242,10 +242,6 @@ db_print_domain(struct domain *d, const char *domain_name, int indent)
 
 	db_print_indent(indent);
 	db_printf("dom_rtattach: %p   ", d->dom_rtattach);
-
-	db_print_indent(indent);
-	db_printf("dom_ifattach: %p   ", d->dom_ifattach);
-	db_printf("dom_ifdetach: %p\n", d->dom_ifdetach);
 }
 
 static void
diff --git a/sys/net/if.c b/sys/net/if.c
index b603c72bd106..3c16246e8b62 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -102,7 +102,6 @@
 #endif /* INET */
 #ifdef INET6
 #include <netinet6/in6_var.h>
-#include <netinet6/in6_ifattach.h>
 #endif /* INET6 */
 #endif /* INET || INET6 */
 
@@ -270,8 +269,6 @@ struct mbuf *(*tbr_dequeue_ptr)(struct ifaltq *, int) = NULL;
  * static functions should be prototyped. Currently they are sorted by
  * declaration order.
  */
-static void	if_attachdomain(void *);
-static void	if_attachdomain1(struct ifnet *);
 static int	ifconf(u_long, caddr_t);
 static void	if_input_default(struct ifnet *, struct mbuf *);
 static int	if_requestencap_default(struct ifnet *, struct if_encap_req *);
@@ -348,11 +345,6 @@ struct sx ifnet_detach_sxlock;
 SX_SYSINIT_FLAGS(ifnet_detach, &ifnet_detach_sxlock, "ifnet_detach_sx",
     SX_RECURSE);
 
-#ifdef VIMAGE
-#define	VNET_IS_SHUTTING_DOWN(_vnet)					\
-    ((_vnet)->vnet_shutdown && (_vnet)->vnet_state < SI_SUB_VNET_DONE)
-#endif
-
 static	if_com_alloc_t *if_com_alloc[256];
 static	if_com_free_t *if_com_free[256];
 
@@ -553,8 +545,6 @@ if_alloc_domain(u_char type, int numa_domain)
 	IF_ADDR_LOCK_INIT(ifp);
 	TASK_INIT(&ifp->if_linktask, 0, do_link_state_change, ifp);
 	TASK_INIT(&ifp->if_addmultitask, 0, if_siocaddmulti, ifp);
-	ifp->if_afdata_initialized = 0;
-	IF_AFDATA_LOCK_INIT(ifp);
 	CK_STAILQ_INIT(&ifp->if_addrhead);
 	CK_STAILQ_INIT(&ifp->if_multiaddrs);
 	CK_STAILQ_INIT(&ifp->if_groups);
@@ -641,7 +631,6 @@ if_free_deferred(epoch_context_t ctx)
 #ifdef MAC
 	mac_ifnet_destroy(ifp);
 #endif /* MAC */
-	IF_AFDATA_DESTROY(ifp);
 	IF_ADDR_LOCK_DESTROY(ifp);
 	ifq_delete(&ifp->if_snd);
 
@@ -930,8 +919,6 @@ if_attach_internal(struct ifnet *ifp, bool vmove)
 #endif
 	}
 
-	if (domain_init_status >= 2)
-		if_attachdomain1(ifp);
 	EVENTHANDLER_INVOKE(ifnet_arrival_event, ifp);
 	if_link_ifnet(ifp);
 	EVENTHANDLER_INVOKE(ifnet_attached_event, ifp);
@@ -947,45 +934,6 @@ if_epochalloc(void *dummy __unused)
 }
 SYSINIT(ifepochalloc, SI_SUB_EPOCH, SI_ORDER_ANY, if_epochalloc, NULL);
 
-static void
-if_attachdomain(void *dummy)
-{
-	struct ifnet *ifp;
-
-	CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link)
-		if_attachdomain1(ifp);
-}
-SYSINIT(domainifattach, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_SECOND,
-    if_attachdomain, NULL);
-
-static void
-if_attachdomain1(struct ifnet *ifp)
-{
-	struct domain *dp;
-
-	/*
-	 * Since dp->dom_ifattach calls malloc() with M_WAITOK, we
-	 * cannot lock ifp->if_afdata initialization, entirely.
-	 */
-	IF_AFDATA_LOCK(ifp);
-	if (ifp->if_afdata_initialized >= domain_init_status) {
-		IF_AFDATA_UNLOCK(ifp);
-		log(LOG_WARNING, "%s called more than once on %s\n",
-		    __func__, ifp->if_xname);
-		return;
-	}
-	ifp->if_afdata_initialized = domain_init_status;
-	IF_AFDATA_UNLOCK(ifp);
-
-	/* address family dependent data region */
-	bzero(ifp->if_afdata, sizeof(ifp->if_afdata));
-	SLIST_FOREACH(dp, &domains, dom_next) {
-		if (dp->dom_ifattach)
-			ifp->if_afdata[dp->dom_family] =
-			    (*dp->dom_ifattach)(ifp);
-	}
-}
-
 /*
  * Remove any unicast or broadcast network addresses from an interface.
  */
@@ -1098,9 +1046,6 @@ static void
 if_detach_internal(struct ifnet *ifp, bool vmove)
 {
 	struct ifaddr *ifa;
-	int i;
-	struct domain *dp;
-	void *if_afdata[AF_MAX];
 #ifdef VIMAGE
 	bool shutdown;
 
@@ -1151,7 +1096,7 @@ if_detach_internal(struct ifnet *ifp, bool vmove)
 		 * if_detach() calls us in void context and does not care
 		 * about an early abort notification, so life is splendid :)
 		 */
-		goto finish_vnet_shutdown;
+		return;
 	}
 #endif
 
@@ -1172,20 +1117,6 @@ if_detach_internal(struct ifnet *ifp, bool vmove)
 #endif
 
 	if_purgeaddrs(ifp);
-
-#ifdef INET
-	in_ifdetach(ifp);
-#endif
-
-#ifdef INET6
-	/*
-	 * Remove all IPv6 kernel structs related to ifp.  This should be done
-	 * before removing routing entries below, since IPv6 interface direct
-	 * routes are expected to be removed by the IPv6-specific kernel API.
-	 * Otherwise, the kernel will detect some inconsistency and bark it.
-	 */
-	in6_ifdetach(ifp);
-#endif
 	if_purgemaddrs(ifp);
 
 	EVENTHANDLER_INVOKE(ifnet_departure_event, ifp);
@@ -1212,43 +1143,6 @@ if_detach_internal(struct ifnet *ifp, bool vmove)
 	}
 
 	rt_flushifroutes(ifp);
-
-#ifdef VIMAGE
-finish_vnet_shutdown:
-#endif
-	/*
-	 * We cannot hold the lock over dom_ifdetach calls as they might
-	 * sleep, for example trying to drain a callout, thus open up the
-	 * theoretical race with re-attaching.
-	 */
-	IF_AFDATA_LOCK(ifp);
-	i = ifp->if_afdata_initialized;
-	ifp->if_afdata_initialized = 0;
-	if (i != 0) {
-		/*
-		 * Defer the dom_ifdetach call.
-		 */
-		_Static_assert(sizeof(if_afdata) == sizeof(ifp->if_afdata),
-		    "array size mismatch");
-		memcpy(if_afdata, ifp->if_afdata, sizeof(if_afdata));
-		memset(ifp->if_afdata, 0, sizeof(ifp->if_afdata));
-	}
-	IF_AFDATA_UNLOCK(ifp);
-	if (i == 0)
-		return;
-	/*
-	 * XXXZL: This net epoch wait is not necessary if we have done right.
-	 * But if we do not, at least we can make a guarantee that threads those
-	 * enter net epoch will see NULL address family dependent data,
-	 * e.g. if_afdata[AF_INET6]. A clear NULL pointer derefence is much
-	 * better than writing to freed memory.
-	 */
-	NET_EPOCH_WAIT();
-	SLIST_FOREACH(dp, &domains, dom_next) {
-		if (dp->dom_ifdetach != NULL &&
-		    if_afdata[dp->dom_family] != NULL)
-			(*dp->dom_ifdetach)(ifp, if_afdata[dp->dom_family]);
-	}
 }
 
 #ifdef VIMAGE
@@ -5121,10 +5015,16 @@ if_getvnet(if_t ifp)
 	return (ifp->if_vnet);
 }
 
-void *
-if_getafdata(if_t ifp, int af)
+struct in_ifinfo *
+if_getinet(if_t ifp)
+{
+	return (ifp->if_inet);
+}
+
+struct in6_ifextra *
+if_getinet6(if_t ifp)
 {
-	return (ifp->if_afdata[af]);
+	return (ifp->if_inet6);
 }
 
 u_int
@@ -5189,8 +5089,6 @@ if_show_ifnet(struct ifnet *ifp)
 	IF_DB_PRINTF("%d", if_amcount);
 	IF_DB_PRINTF("%p", if_addr);
 	IF_DB_PRINTF("%p", if_broadcastaddr);
-	IF_DB_PRINTF("%p", if_afdata);
-	IF_DB_PRINTF("%d", if_afdata_initialized);
 	IF_DB_PRINTF("%u", if_fib);
 	IF_DB_PRINTF("%p", if_vnet);
 	IF_DB_PRINTF("%p", if_home_vnet);
diff --git a/sys/net/if_loop.c b/sys/net/if_loop.c
index ec0ff0e77aa6..37309260a0d3 100644
--- a/sys/net/if_loop.c
+++ b/sys/net/if_loop.c
@@ -151,7 +151,7 @@ vnet_loif_init(const void *unused __unused)
 	struct ifc_data ifd = { .unit = 0 };
 	ifc_create_ifp(loname, &ifd, &V_loif);
 }
-VNET_SYSINIT(vnet_loif_init, SI_SUB_PSEUDO, SI_ORDER_ANY,
+VNET_SYSINIT(vnet_loif_init, SI_SUB_PROTO_IF, SI_ORDER_ANY,
     vnet_loif_init, NULL);
 
 #ifdef VIMAGE
diff --git a/sys/net/if_private.h b/sys/net/if_private.h
index b8cd0722eba6..c4ade7308df4 100644
--- a/sys/net/if_private.h
+++ b/sys/net/if_private.h
@@ -101,9 +101,8 @@ struct ifnet {
 	struct	ifaddr	*if_addr;	/* pointer to link-level address */
 	void	*if_hw_addr;		/* hardware link-level address */
 	const u_int8_t *if_broadcastaddr; /* linklevel broadcast bytestring */
-	struct	mtx if_afdata_lock;
-	void	*if_afdata[AF_MAX];
-	int	if_afdata_initialized;
+	struct in_ifinfo	*if_inet;
+	struct in6_ifextra	*if_inet6;
 
 	/* Additional features hung off the interface. */
 	u_int	if_fib;			/* interface FIB */
@@ -193,20 +192,6 @@ struct ifnet {
 	int	if_ispare[4];		/* general use */
 };
 
-#define	IF_AFDATA_LOCK_INIT(ifp)	\
-	mtx_init(&(ifp)->if_afdata_lock, "if_afdata", NULL, MTX_DEF)
-
-#define	IF_AFDATA_WLOCK(ifp)	mtx_lock(&(ifp)->if_afdata_lock)
-#define	IF_AFDATA_WUNLOCK(ifp)	mtx_unlock(&(ifp)->if_afdata_lock)
-#define	IF_AFDATA_LOCK(ifp)	IF_AFDATA_WLOCK(ifp)
-#define	IF_AFDATA_UNLOCK(ifp)	IF_AFDATA_WUNLOCK(ifp)
-#define	IF_AFDATA_TRYLOCK(ifp)	mtx_trylock(&(ifp)->if_afdata_lock)
-#define	IF_AFDATA_DESTROY(ifp)	mtx_destroy(&(ifp)->if_afdata_lock)
-
-#define	IF_AFDATA_LOCK_ASSERT(ifp)	MPASS(in_epoch(net_epoch_preempt) || mtx_owned(&(ifp)->if_afdata_lock))
-#define	IF_AFDATA_WLOCK_ASSERT(ifp)	mtx_assert(&(ifp)->if_afdata_lock, MA_OWNED)
-#define	IF_AFDATA_UNLOCK_ASSERT(ifp)	mtx_assert(&(ifp)->if_afdata_lock, MA_NOTOWNED)
-
 #define IF_LLADDR(ifp)							\
     LLADDR((struct sockaddr_dl *)((ifp)->if_addr->ifa_addr))
 
diff --git a/sys/net/if_var.h b/sys/net/if_var.h
index cbc4969918ba..4fb51aca0cd7 100644
--- a/sys/net/if_var.h
+++ b/sys/net/if_var.h
@@ -673,7 +673,8 @@ void *if_getl2com(if_t ifp);
 struct ifvlantrunk *if_getvlantrunk(if_t ifp);
 bool if_altq_is_enabled(if_t ifp);
 
-void *if_getafdata(if_t ifp, int);
+struct in_ifinfo *if_getinet(if_t ifp);
+struct in6_ifextra *if_getinet6(if_t ifp);
 
 int if_snd_tag_alloc(if_t ifp, union if_snd_tag_alloc_params *params,
     struct m_snd_tag **mstp);
diff --git a/sys/net/vnet.h b/sys/net/vnet.h
index 670e99a455ae..f8ffcb4e2b76 100644
--- a/sys/net/vnet.h
+++ b/sys/net/vnet.h
@@ -395,6 +395,9 @@ do {									\
 	}								\
 } while(0)
 
+#define	VNET_IS_SHUTTING_DOWN(_vnet)	\
+	    ((_vnet)->vnet_shutdown && (_vnet)->vnet_state < SI_SUB_VNET_DONE)
+
 #else /* !VIMAGE */
 
 /*
diff --git a/sys/netinet/icmp6.h b/sys/netinet/icmp6.h
index 2ca5b3433e47..082ef5d29ce9 100644
--- a/sys/netinet/icmp6.h
+++ b/sys/netinet/icmp6.h
@@ -718,7 +718,7 @@ int	icmp6_ratelimit(const struct in6_addr *, const int, const int);
 do {								\
 	if (ifp)						\
 		counter_u64_add(((struct in6_ifextra *)		\
-		    ((ifp)->if_afdata[AF_INET6]))->icmp6_ifstat[\
+		    ((ifp)->if_inet6))->icmp6_ifstat[		\
 		    offsetof(struct icmp6_ifstat, tag) / sizeof(uint64_t)], 1);\
 } while (/*CONSTCOND*/ 0)
 
diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c
index 7b223f1f2f11..8d65b88913b8 100644
--- a/sys/netinet/if_ether.c
+++ b/sys/netinet/if_ether.c
@@ -1485,8 +1485,8 @@ static void
 arp_iflladdr(void *arg __unused, struct ifnet *ifp)
 {
 	/* if_bridge can update its lladdr during if_vmove(), after we've done
-	 * if_detach_internal()/dom_ifdetach(). */
-	if (ifp->if_afdata[AF_INET] == NULL)
+	 * with in_ifdetach(). XXXGL: needs to be fixed. */
+	if (ifp->if_inet == NULL)
 		return;
 
 	lltable_update_ifaddr(LLTABLE(ifp));
diff --git a/sys/netinet/igmp.c b/sys/netinet/igmp.c
index ad22efb16495..de9d38c7fb9d 100644
--- a/sys/netinet/igmp.c
+++ b/sys/netinet/igmp.c
@@ -690,7 +690,7 @@ igmp_ifdetach(struct ifnet *ifp)
 	SLIST_INIT(&inm_free_tmp);
 	IGMP_LOCK();
 
-	igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
+	igi = ((struct in_ifinfo *)ifp->if_inet)->ii_igmp;
 	if (igi->igi_version == IGMP_VERSION_3) {
 		IF_ADDR_WLOCK(ifp);
 		NET_EPOCH_ENTER(et);
@@ -781,7 +781,7 @@ igmp_input_v1_query(struct ifnet *ifp, const struct ip *ip,
 	IN_MULTI_LIST_LOCK();
 	IGMP_LOCK();
 
-	igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
+	igi = ((struct in_ifinfo *)ifp->if_inet)->ii_igmp;
 	KASSERT(igi != NULL, ("%s: no igmp_ifsoftc for ifp %p", __func__, ifp));
 
 	if (igi->igi_flags & IGIF_LOOPBACK) {
@@ -874,7 +874,7 @@ igmp_input_v2_query(struct ifnet *ifp, const struct ip *ip,
 	IN_MULTI_LIST_LOCK();
 	IGMP_LOCK();
 
-	igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
+	igi = ((struct in_ifinfo *)ifp->if_inet)->ii_igmp;
 	KASSERT(igi != NULL, ("%s: no igmp_ifsoftc for ifp %p", __func__, ifp));
 
 	if (igi->igi_flags & IGIF_LOOPBACK) {
@@ -1066,7 +1066,7 @@ igmp_input_v3_query(struct ifnet *ifp, const struct ip *ip,
 	IN_MULTI_LIST_LOCK();
 	IGMP_LOCK();
 
-	igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
+	igi = ((struct in_ifinfo *)ifp->if_inet)->ii_igmp;
 	KASSERT(igi != NULL, ("%s: no igmp_ifsoftc for ifp %p", __func__, ifp));
 
 	if (igi->igi_flags & IGIF_LOOPBACK) {
@@ -2347,7 +2347,7 @@ igmp_change_state(struct in_multi *inm)
 
 	IGMP_LOCK();
 
-	igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
+	igi = ((struct in_ifinfo *)ifp->if_inet)->ii_igmp;
 	KASSERT(igi != NULL, ("%s: no igmp_ifsoftc for ifp %p", __func__, ifp));
 
 	/*
diff --git a/sys/netinet/in.c b/sys/netinet/in.c
index e824c937af8e..510cfa79d54b 100644
--- a/sys/netinet/in.c
+++ b/sys/netinet/in.c
@@ -669,7 +669,7 @@ in_aifaddr_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp, struct ucred *cred
 		struct in_addr allhosts_addr;
 		struct in_ifinfo *ii;
 
-		ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]);
+		ii = (struct in_ifinfo *)ifp->if_inet;
 		allhosts_addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
 
 		error = in_joingroup(ifp, &allhosts_addr, NULL,
@@ -789,7 +789,7 @@ in_difaddr_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp, struct ucred *cred
 	if (iaIsLast && (ifp->if_flags & IFF_MULTICAST)) {
 		struct in_ifinfo *ii;
 
-		ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]);
+		ii = (struct in_ifinfo *)ifp->if_inet;
 		if (ii->ii_allhosts) {
 			(void)in_leavegroup(ii->ii_allhosts, NULL);
 			ii->ii_allhosts = NULL;
@@ -1329,26 +1329,62 @@ in_ifnet_broadcast(struct in_addr in, struct ifnet *ifp)
 	return (false);
 }
 
+
+static struct lltable *in_lltattach(struct ifnet *);
+void
+in_ifattach(void *arg __unused, struct ifnet *ifp)
+{
+	struct in_ifinfo *ii;
+
+	ii = malloc(sizeof(struct in_ifinfo), M_IFADDR, M_WAITOK|M_ZERO);
+	ii->ii_llt = in_lltattach(ifp);
+	ii->ii_igmp = igmp_domifattach(ifp);
+	ifp->if_inet = ii;
+}
+EVENTHANDLER_DEFINE(ifnet_arrival_event, in_ifattach, NULL,
+    EVENTHANDLER_PRI_ANY);
+
 /*
  * On interface removal, clean up IPv4 data structures hung off of the ifnet.
  */
-void
-in_ifdetach(struct ifnet *ifp)
+static void
+in_ifdetach(void *arg __unused, struct ifnet *ifp)
 {
-	IN_MULTI_LOCK();
-	in_pcbpurgeif0(&V_ripcbinfo, ifp);
-	in_pcbpurgeif0(&V_udbinfo, ifp);
-	in_pcbpurgeif0(&V_ulitecbinfo, ifp);
-	in_purgemaddrs(ifp);
-	IN_MULTI_UNLOCK();
+	struct in_ifinfo *ii = ifp->if_inet;
 
+#ifdef VIMAGE
 	/*
-	 * Make sure all multicast deletions invoking if_ioctl() are
-	 * completed before returning. Else we risk accessing a freed
-	 * ifnet structure pointer.
+	 * On VNET shutdown abort here as the stack teardown will do all
+	 * the work top-down for us.  XXXGL: this logic is copied from
+	 * if_detach() before dom_ifattach removal.  Ideally we'd like to have
+	 * same logic for VNET shutdown and normal detach.  This means that
+	 * interfaces should be detach before protocols destroyed during VNET
+	 * shutdown.
 	 */
-	inm_release_wait(NULL);
+	if (!VNET_IS_SHUTTING_DOWN(ifp->if_vnet))
+#endif
+	{
+		IN_MULTI_LOCK();
+		in_pcbpurgeif0(&V_ripcbinfo, ifp);
+		in_pcbpurgeif0(&V_udbinfo, ifp);
+		in_pcbpurgeif0(&V_ulitecbinfo, ifp);
+		in_purgemaddrs(ifp);
+		IN_MULTI_UNLOCK();
+
+		/*
+		 * Make sure all multicast deletions invoking if_ioctl() are
+		 * completed before returning. Else we risk accessing a freed
+		 * ifnet structure pointer.
+		 */
+		inm_release_wait(NULL);
+	}
+
+	igmp_domifdetach(ifp);
+	lltable_free(ii->ii_llt);
+	free(ii, M_IFADDR);
 }
+EVENTHANDLER_DEFINE(ifnet_departure_event, in_ifdetach, NULL,
+    EVENTHANDLER_PRI_ANY);
 
 static void
 in_ifnet_event(void *arg __unused, struct ifnet *ifp, int event)
@@ -1862,35 +1898,9 @@ in_lltattach(struct ifnet *ifp)
 struct lltable *
 in_lltable_get(struct ifnet *ifp)
 {
-	struct lltable *llt = NULL;
-
-	void *afdata_ptr = ifp->if_afdata[AF_INET];
-	if (afdata_ptr != NULL)
-		llt = ((struct in_ifinfo *)afdata_ptr)->ii_llt;
-	return (llt);
-}
-
-void *
-in_domifattach(struct ifnet *ifp)
-{
-	struct in_ifinfo *ii;
-
-	ii = malloc(sizeof(struct in_ifinfo), M_IFADDR, M_WAITOK|M_ZERO);
-
-	ii->ii_llt = in_lltattach(ifp);
-	ii->ii_igmp = igmp_domifattach(ifp);
-
-	return (ii);
-}
-
-void
-in_domifdetach(struct ifnet *ifp, void *aux)
-{
-	struct in_ifinfo *ii = (struct in_ifinfo *)aux;
-
-	MPASS(ifp->if_afdata[AF_INET] == NULL);
+	/* XXXGL: ??? */
+	if (ifp->if_inet == NULL)
+		return (NULL);
 
-	igmp_domifdetach(ifp);
-	lltable_free(ii->ii_llt);
-	free(ii, M_IFADDR);
+	return (((struct in_ifinfo *)ifp->if_inet)->ii_llt);
 }
diff --git a/sys/netinet/in.h b/sys/netinet/in.h
index 3f2c388548ec..0cd55bd1e409 100644
--- a/sys/netinet/in.h
+++ b/sys/netinet/in.h
@@ -684,7 +684,6 @@ int	 inet_aton(const char *, struct in_addr *); /* in libkern */
 char	*inet_ntoa_r(struct in_addr ina, char *buf); /* in libkern */
 char	*inet_ntop(int, const void *, char *, socklen_t); /* in libkern */
 int	 inet_pton(int af, const char *, void *); /* in libkern */
-void	 in_ifdetach(struct ifnet *);
 
 static inline bool
 in_broadcast(struct in_addr in)
diff --git a/sys/netinet/in_mcast.c b/sys/netinet/in_mcast.c
index ba112afbf002..131e72780ebe 100644
--- a/sys/netinet/in_mcast.c
+++ b/sys/netinet/in_mcast.c
@@ -500,7 +500,7 @@ in_getmulti(struct ifnet *ifp, const struct in_addr *group,
 
 	IN_MULTI_LOCK_ASSERT();
 
-	ii = (struct in_ifinfo *)ifp->if_afdata[AF_INET];
+	ii = (struct in_ifinfo *)ifp->if_inet;
 	IN_MULTI_LIST_LOCK();
 	inm = inm_lookup(ifp, *group);
 	if (inm != NULL) {
diff --git a/sys/netinet/in_proto.c b/sys/netinet/in_proto.c
index 3ec515d216fa..ff3040bfc7b1 100644
--- a/sys/netinet/in_proto.c
+++ b/sys/netinet/in_proto.c
@@ -76,8 +76,6 @@ struct domain inetdomain = {
 #ifdef VIMAGE
 	.dom_rtdetach =		in_detachhead,
 #endif
-	.dom_ifattach =		in_domifattach,
-	.dom_ifdetach =		in_domifdetach,
 	.dom_nprotosw =		14,
 	.dom_protosw = {
 		&tcp_protosw,
diff --git a/sys/netinet/in_var.h b/sys/netinet/in_var.h
index 1f6f6edb9219..311d82da4605 100644
--- a/sys/netinet/in_var.h
+++ b/sys/netinet/in_var.h
@@ -102,8 +102,7 @@ struct in_ifaddr {
 	((((d).s_addr ^ (a).s_addr) & (m).s_addr)) == 0 )
 #endif
 
-#define LLTABLE(ifp)	\
-	((struct in_ifinfo *)(ifp)->if_afdata[AF_INET])->ii_llt
+#define LLTABLE(ifp)	((struct in_ifinfo *)(ifp)->if_inet)->ii_llt
 /*
  * Hash table for IP addresses.
  */
@@ -471,9 +470,9 @@ void	ip_input(struct mbuf *);
 void	ip_direct_input(struct mbuf *);
 void	in_ifadown(struct ifaddr *ifa, int);
 struct	mbuf	*ip_tryforward(struct mbuf *);
-void	*in_domifattach(struct ifnet *);
-void	in_domifdetach(struct ifnet *, void *);
 struct rib_head *in_inithead(uint32_t fibnum);
+void	in_ifattach(void *, struct ifnet *);
+
 #ifdef VIMAGE
 void	in_detachhead(struct rib_head *rh);
 #endif
diff --git a/sys/netinet/ip_input.c b/sys/netinet/ip_input.c
index 6ddec6726428..2e0635f8e482 100644
--- a/sys/netinet/ip_input.c
+++ b/sys/netinet/ip_input.c
@@ -352,6 +352,7 @@ VNET_SYSINIT(ip_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
 static void
 ip_init(const void *unused __unused)
 {
+	struct ifnet *ifp;
 
 	ipreass_init();
 
@@ -376,6 +377,14 @@ ip_init(const void *unused __unused)
 #ifdef	RSS
 	netisr_register(&ip_direct_nh);
 #endif
+	/*
+	 * XXXGL: we use SYSINIT() here, but go over V_ifnet.  It was the same
+	 * way before dom_ifattach removal.  This worked because when any
+	 * non-default vnet is created, there are no interfaces inside.
+	 * Eventually this needs to be fixed.
+	 */
+	CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link)
+		in_ifattach(NULL, ifp);
 }
 SYSINIT(ip_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip_init, NULL);
 
diff --git a/sys/netinet6/in6.c b/sys/netinet6/in6.c
index 158129258587..a953bb5546d6 100644
--- a/sys/netinet6/in6.c
+++ b/sys/netinet6/in6.c
@@ -478,7 +478,7 @@ in6_control_ioctl(u_long cmd, void *data,
 		/* FALLTHROUGH */
 	case SIOCGIFSTAT_IN6:
 	case SIOCGIFSTAT_ICMP6:
-		if (ifp->if_afdata[AF_INET6] == NULL) {
+		if (ifp->if_inet6 == NULL) {
 			error = EPFNOSUPPORT;
 			goto out;
 		}
@@ -525,15 +525,13 @@ in6_control_ioctl(u_long cmd, void *data,
 		break;
 
 	case SIOCGIFSTAT_IN6:
-		COUNTER_ARRAY_COPY(((struct in6_ifextra *)
-		    ifp->if_afdata[AF_INET6])->in6_ifstat,
+		COUNTER_ARRAY_COPY(ifp->if_inet6->in6_ifstat,
 		    &ifr->ifr_ifru.ifru_stat,
 		    sizeof(struct in6_ifstat) / sizeof(uint64_t));
 		break;
 
 	case SIOCGIFSTAT_ICMP6:
-		COUNTER_ARRAY_COPY(((struct in6_ifextra *)
-		    ifp->if_afdata[AF_INET6])->icmp6_ifstat,
+		COUNTER_ARRAY_COPY(ifp->if_inet6->icmp6_ifstat,
 		    &ifr->ifr_ifru.ifru_icmp6stat,
 		    sizeof(struct icmp6_ifstat) / sizeof(uint64_t));
 		break;
@@ -2567,16 +2565,14 @@ in6_lltattach(struct ifnet *ifp)
 struct lltable *
 in6_lltable_get(struct ifnet *ifp)
 {
-	struct lltable *llt = NULL;
+	if (ifp->if_inet6 == NULL)
+		return (NULL);
 
-	void *afdata_ptr = ifp->if_afdata[AF_INET6];
-	if (afdata_ptr != NULL)
-		llt = ((struct in6_ifextra *)afdata_ptr)->lltable;
-	return (llt);
+	return (ifp->if_inet6->lltable);
 }
 
-void *
-in6_domifattach(struct ifnet *ifp)
+void
+in6_ifarrival(void *arg __unused, struct ifnet *ifp)
 {
 	struct in6_ifextra *ext;
 
@@ -2584,7 +2580,8 @@ in6_domifattach(struct ifnet *ifp)
 	switch (ifp->if_type) {
 	case IFT_PFLOG:
 	case IFT_PFSYNC:
-		return (NULL);
+		ifp->if_inet6 = NULL;
+		return;
 	}
 	ext = (struct in6_ifextra *)malloc(sizeof(*ext), M_IFADDR, M_WAITOK);
 	bzero(ext, sizeof(*ext));
@@ -2606,8 +2603,10 @@ in6_domifattach(struct ifnet *ifp)
 
 	ext->mld_ifinfo = mld_domifattach(ifp);
 
-	return ext;
+	ifp->if_inet6 = ext;
 }
+EVENTHANDLER_DEFINE(ifnet_arrival_event, in6_ifarrival, NULL,
+    EVENTHANDLER_PRI_ANY);
 
 uint32_t
 in6_ifmtu(struct ifnet *ifp)
@@ -2615,26 +2614,6 @@ in6_ifmtu(struct ifnet *ifp)
 	return (IN6_LINKMTU(ifp));
 }
 
-void
-in6_domifdetach(struct ifnet *ifp, void *aux)
-{
-	struct in6_ifextra *ext = (struct in6_ifextra *)aux;
-
-	MPASS(ifp->if_afdata[AF_INET6] == NULL);
-
-	mld_domifdetach(ifp);
-	scope6_ifdetach(ext->scope6_id);
-	nd6_ifdetach(ifp, ext->nd_ifinfo);
-	lltable_free(ext->lltable);
-	COUNTER_ARRAY_FREE(ext->in6_ifstat,
-	    sizeof(struct in6_ifstat) / sizeof(uint64_t));
-	free(ext->in6_ifstat, M_IFADDR);
-	COUNTER_ARRAY_FREE(ext->icmp6_ifstat,
-	    sizeof(struct icmp6_ifstat) / sizeof(uint64_t));
-	free(ext->icmp6_ifstat, M_IFADDR);
-	free(ext, M_IFADDR);
-}
-
 /*
  * Convert sockaddr_in6 to sockaddr_in.  Original sockaddr_in6 must be
  * v4 mapped addr or v4 compat addr
@@ -2736,7 +2715,7 @@ in6_purge_proxy_ndp(struct ifnet *ifp)
 	struct lltable *llt;
 	bool need_purge;
 
-	if (ifp->if_afdata[AF_INET6] == NULL)
+	if (ifp->if_inet6 == NULL)
 		return;
 
 	llt = LLTABLE6(ifp);
diff --git a/sys/netinet6/in6_ifattach.c b/sys/netinet6/in6_ifattach.c
index 090ba610460b..a2d236cccc41 100644
--- a/sys/netinet6/in6_ifattach.c
+++ b/sys/netinet6/in6_ifattach.c
@@ -50,6 +50,7 @@
 #include <net/if_dl.h>
 #include <net/if_private.h>
 #include <net/if_types.h>
+#include <net/if_llatbl.h>
 #include <net/route.h>
 #include <net/vnet.h>
 
@@ -783,7 +784,8 @@ in6_ifattach(struct ifnet *ifp, struct ifnet *altifp)
 {
 	struct in6_ifaddr *ia;
 
-	if (ifp->if_afdata[AF_INET6] == NULL)
+	/* XXXGL: can this happen after IFT_PFLOG and IFT_PFSYNC are gone? */
+	if (ifp->if_inet6 == NULL)
 		return;
 	/*
 	 * quirks based on interface type
@@ -857,7 +859,8 @@ _in6_ifdetach(struct ifnet *ifp, int purgeulp)
 {
 	struct ifaddr *ifa, *next;
 
-	if (ifp->if_afdata[AF_INET6] == NULL)
+	/* XXXGL: can this happen after IFT_PFLOG and IFT_PFSYNC are gone? */
+	if (ifp->if_inet6 == NULL)
 		return;
 
 	/*
@@ -895,6 +898,38 @@ in6_ifdetach(struct ifnet *ifp)
 	_in6_ifdetach(ifp, 1);
 }
 
+static void
+in6_ifdeparture(void *arg __unused, struct ifnet *ifp)
+{
+	struct in6_ifextra *ext = ifp->if_inet6;
+
+	/* XXXGL: can this happen after IFT_PFLOG and IFT_PFSYNC are gone? */
+	if (ifp->if_inet6 == NULL)
+		return;
+
+#ifdef VIMAGE
+	/*
+	 * On VNET shutdown abort here as the stack teardown will do all
+	 * the work top-down for us.  XXXGL: see comment in in.c:in_ifdetach().
+	 */
+	if (!VNET_IS_SHUTTING_DOWN(ifp->if_vnet))
+#endif
+		_in6_ifdetach(ifp, 1);
+	mld_domifdetach(ifp);
+	scope6_ifdetach(ext->scope6_id);
+	nd6_ifdetach(ifp, ext->nd_ifinfo);
+	lltable_free(ext->lltable);
+	COUNTER_ARRAY_FREE(ext->in6_ifstat,
+	    sizeof(struct in6_ifstat) / sizeof(uint64_t));
+	free(ext->in6_ifstat, M_IFADDR);
+	COUNTER_ARRAY_FREE(ext->icmp6_ifstat,
+	    sizeof(struct icmp6_ifstat) / sizeof(uint64_t));
+	free(ext->icmp6_ifstat, M_IFADDR);
+	free(ext, M_IFADDR);
+}
+EVENTHANDLER_DEFINE(ifnet_departure_event, in6_ifdeparture, NULL,
+    EVENTHANDLER_PRI_ANY);
+
 void
 in6_ifdetach_destroy(struct ifnet *ifp)
 {
diff --git a/sys/netinet6/in6_mcast.c b/sys/netinet6/in6_mcast.c
index 613bd14428bb..4075e75eac85 100644
--- a/sys/netinet6/in6_mcast.c
+++ b/sys/netinet6/in6_mcast.c
@@ -400,7 +400,7 @@ in6_getmulti(struct ifnet *ifp, const struct in6_addr *group,
 	/*
 	 * Does ifp support IPv6 multicasts?
 	 */
-	if (ifp->if_afdata[AF_INET6] == NULL)
+	if (ifp->if_inet6 == NULL)
 		error = ENODEV;
 	else
 		inm = in6m_lookup_locked(ifp, group);
diff --git a/sys/netinet6/in6_proto.c b/sys/netinet6/in6_proto.c
index f3ed72719abf..dbbe7c4b3eca 100644
--- a/sys/netinet6/in6_proto.c
+++ b/sys/netinet6/in6_proto.c
@@ -111,8 +111,6 @@ struct domain inet6domain = {
 #ifdef VIMAGE
 	.dom_rtdetach =		in6_detachhead,
 #endif
-	.dom_ifattach =		in6_domifattach,
-	.dom_ifdetach =		in6_domifdetach,
 	.dom_nprotosw =		14,
 	.dom_protosw = {
 		&tcp6_protosw,
diff --git a/sys/netinet6/in6_var.h b/sys/netinet6/in6_var.h
index 1210937a5dc4..0cfdde652c0a 100644
--- a/sys/netinet6/in6_var.h
+++ b/sys/netinet6/in6_var.h
@@ -109,8 +109,8 @@ struct in6_ifextra {
 	u_int dad_failures;	/* DAD failures when using RFC 7217 stable addresses */
 };
 
-#define	LLTABLE6(ifp)	(((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->lltable)
-#define	DAD_FAILURES(ifp)	(((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->dad_failures)
+#define	LLTABLE6(ifp)	((ifp)->if_inet6->lltable)
+#define	DAD_FAILURES(ifp)	((ifp)->if_inet6->dad_failures)
 
 #ifdef _KERNEL
 
@@ -545,8 +545,7 @@ extern struct rmlock in6_ifaddr_lock;
 #define in6_ifstat_inc(ifp, tag) \
 do {								\
 	if (ifp)						\
-		counter_u64_add(((struct in6_ifextra *)		\
-		    ((ifp)->if_afdata[AF_INET6]))->in6_ifstat[	\
+		counter_u64_add((ifp)->if_inet6->in6_ifstat[	\
 		    offsetof(struct in6_ifstat, tag) / sizeof(uint64_t)], 1);\
 } while (/*CONSTCOND*/ 0)
 #endif /* _KERNEL */
@@ -867,8 +866,6 @@ void	in6_purgeaddr(struct ifaddr *);
 void	in6_purgeifaddr(struct in6_ifaddr *);
 int	in6if_do_dad(struct ifnet *);
 void	in6_savemkludge(struct in6_ifaddr *);
-void	*in6_domifattach(struct ifnet *);
-void	in6_domifdetach(struct ifnet *, void *);
 uint32_t in6_ifmtu(struct ifnet *);
 struct rib_head *in6_inithead(uint32_t fibnum);
 void	in6_detachhead(struct rib_head *rh);
@@ -893,6 +890,8 @@ int	in6_src_ioctl(u_long, caddr_t);
 void	in6_newaddrmsg(struct in6_ifaddr *, int);
 
 void	in6_purge_proxy_ndp(struct ifnet *);
+void	in6_ifarrival(void *, struct ifnet *);
+
 /*
  * Extended API for IPv6 FIB support.
  */
diff --git a/sys/netinet6/ip6_input.c b/sys/netinet6/ip6_input.c
index 380391fd71f4..29fa4741a509 100644
--- a/sys/netinet6/ip6_input.c
+++ b/sys/netinet6/ip6_input.c
@@ -286,6 +286,7 @@ VNET_SYSINIT(ip6_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
 static void
 ip6_init(void *arg __unused)
 {
+	struct ifnet *ifp;
 
 	/*
 	 * Register statically those protocols that are unlikely to ever go
@@ -312,6 +313,12 @@ ip6_init(void *arg __unused)
 #ifdef RSS
 	netisr_register(&ip6_direct_nh);
 #endif
+	/*
+         * XXXGL: we use SYSINIT() here, but go over V_ifnet.  See comment
+	 * in sys/netinet/ip_input.c:ip_init().
+         */
+        CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link)
+                in6_ifarrival(NULL, ifp);
 }
 SYSINIT(ip6_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip6_init, NULL);
 
diff --git a/sys/netinet6/ip6_output.c b/sys/netinet6/ip6_output.c
index 8ade50b13568..eb5a3a971ea0 100644
--- a/sys/netinet6/ip6_output.c
+++ b/sys/netinet6/ip6_output.c
@@ -2920,7 +2920,7 @@ ip6_setpktopt(int optname, u_char *buf, int len, struct ip6_pktopts *opt,
 			if (ifp == NULL)
 				return (ENXIO);
 		}
-		if (ifp != NULL && (ifp->if_afdata[AF_INET6] == NULL ||
+		if (ifp != NULL && (ifp->if_inet6 == NULL ||
 		    (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) != 0))
 			return (ENETDOWN);
 
diff --git a/sys/netinet6/mld6_var.h b/sys/netinet6/mld6_var.h
index 96b841f1564b..d75ac2450c10 100644
--- a/sys/netinet6/mld6_var.h
+++ b/sys/netinet6/mld6_var.h
@@ -155,8 +155,7 @@ struct mld_ifsoftc {
 /*
  * Per-link MLD context.
  */
-#define MLD_IFINFO(ifp) \
-	(((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->mld_ifinfo)
+#define MLD_IFINFO(ifp)	((ifp)->if_inet6->mld_ifinfo)
 
 struct in6_multi_head;
 int	mld_change_state(struct in6_multi *, const int);
diff --git a/sys/netinet6/nd6.c b/sys/netinet6/nd6.c
index ecf368327833..595e0b4ac54f 100644
--- a/sys/netinet6/nd6.c
+++ b/sys/netinet6/nd6.c
@@ -224,7 +224,8 @@ nd6_lle_event(void *arg __unused, struct llentry *lle, int evt)
 static void
 nd6_iflladdr(void *arg __unused, struct ifnet *ifp)
 {
-	if (ifp->if_afdata[AF_INET6] == NULL)
+	/* XXXGL: ??? */
+	if (ifp->if_inet6 == NULL)
 		return;
 
 	lltable_update_ifaddr(LLTABLE6(ifp));
@@ -357,7 +358,8 @@ nd6_ifdetach(struct ifnet *ifp, struct nd_ifinfo *nd)
 void
 nd6_setmtu(struct ifnet *ifp)
 {
-	if (ifp->if_afdata[AF_INET6] == NULL)
+	/* XXXGL: ??? */
+	if (ifp->if_inet6 == NULL)
 		return;
 
 	nd6_setmtu0(ifp, ND_IFINFO(ifp));
@@ -1644,7 +1646,8 @@ nd6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp)
 	struct epoch_tracker et;
 	int error = 0;
 
-	if (ifp->if_afdata[AF_INET6] == NULL)
+	/* XXXGL: ??? */
+	if (ifp->if_inet6 == NULL)
 		return (EPFNOSUPPORT);
 	switch (cmd) {
 	case OSIOCGIFINFO_IN6:
@@ -2137,7 +2140,7 @@ nd6_slowtimo(void *arg)
 	    nd6_slowtimo, curvnet);
 	NET_EPOCH_ENTER(et);
 	CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) {
-		if (ifp->if_afdata[AF_INET6] == NULL)
+		if (ifp->if_inet6 == NULL)
 			continue;
 		nd6if = ND_IFINFO(ifp);
 		if (nd6if->basereachable && /* already initialized */
diff --git a/sys/netinet6/nd6.h b/sys/netinet6/nd6.h
index e484c709e29a..3051397ec33f 100644
--- a/sys/netinet6/nd6.h
+++ b/sys/netinet6/nd6.h
@@ -98,8 +98,7 @@ struct nd_ifinfo {
 #endif
 
 #ifdef _KERNEL
-#define ND_IFINFO(ifp) \
-	(((struct in6_ifextra *)if_getafdata(ifp, AF_INET6))->nd_ifinfo)
+#define ND_IFINFO(ifp)	((if_getinet6(ifp))->nd_ifinfo)
 #define IN6_LINKMTU(ifp) \
 	((ND_IFINFO(ifp)->linkmtu && ND_IFINFO(ifp)->linkmtu < (ifp)->if_mtu) \
 	    ? ND_IFINFO(ifp)->linkmtu \
diff --git a/sys/netinet6/scope6.c b/sys/netinet6/scope6.c
index a683ebdec956..6862c75fb5e7 100644
--- a/sys/netinet6/scope6.c
+++ b/sys/netinet6/scope6.c
@@ -73,8 +73,7 @@ static struct mtx scope6_lock;
 VNET_DEFINE_STATIC(struct scope6_id, sid_default);
 #define	V_sid_default			VNET(sid_default)
 
-#define SID(ifp) \
-	(((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->scope6_id)
+#define SID(ifp)	((ifp)->if_inet6->scope6_id)
 
 static int	scope6_get(struct ifnet *, struct scope6_id *);
 static int	scope6_set(struct ifnet *, struct scope6_id *);
@@ -118,7 +117,7 @@ scope6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp)
 {
 	struct in6_ifreq *ifr;
 
-	if (ifp->if_afdata[AF_INET6] == NULL)
+	if (ifp->if_inet6 == NULL)
 		return (EPFNOSUPPORT);
 
 	ifr = (struct in6_ifreq *)data;
@@ -433,7 +432,8 @@ in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id)
 			struct epoch_tracker et;
 
 			NET_EPOCH_ENTER(et);
-			if (ifp->if_afdata[AF_INET6] == NULL) {
+			/* XXXGL */
+			if (ifp->if_inet6 == NULL) {
 				NET_EPOCH_EXIT(et);
 				return (ENETDOWN);
 			}
@@ -517,7 +517,7 @@ in6_getlinkifnet(uint32_t zoneid)
 		return (NULL);
 
 	/* An interface might not be IPv6 capable. */
-	if (ifp->if_afdata[AF_INET6] == NULL) {
+	if (ifp->if_inet6 == NULL) {
 		log(LOG_NOTICE,
 		    "%s: embedded scope points to an interface without "
 		    "IPv6: %s%%%d.\n", __func__,
diff --git a/sys/sys/domain.h b/sys/sys/domain.h
index 5639ef1c01e5..b51d1b818009 100644
--- a/sys/sys/domain.h
+++ b/sys/sys/domain.h
@@ -56,8 +56,6 @@ struct domain {
 		(uint32_t);
 	void	(*dom_rtdetach)		/* clean up routing table */
 		(struct rib_head *);
-	void	*(*dom_ifattach)(struct ifnet *);
-	void	(*dom_ifdetach)(struct ifnet *, void *);
 	struct	protosw *dom_protosw[];
 };
 
diff --git a/sys/sys/kernel.h b/sys/sys/kernel.h
index 417afd4dbbe4..da502f8ba4b4 100644
--- a/sys/sys/kernel.h
+++ b/sys/sys/kernel.h
@@ -154,9 +154,9 @@ enum sysinit_sub_id {
 	SI_SUB_EXEC		= 0x7400000,	/* execve() handlers */
 	SI_SUB_PROTO_BEGIN	= 0x8000000,	/* VNET initialization */
 	SI_SUB_PROTO_PFIL	= 0x8100000,	/* Initialize pfil before FWs */
+	SI_SUB_PROTO_MC		= 0x8300000,	/* Multicast */
 	SI_SUB_PROTO_IF		= 0x8400000,	/* interfaces */
 	SI_SUB_PROTO_DOMAININIT	= 0x8600000,	/* domain registration system */
-	SI_SUB_PROTO_MC		= 0x8700000,	/* Multicast */
 	SI_SUB_PROTO_DOMAIN	= 0x8800000,	/* domains (address families?) */
 	SI_SUB_PROTO_FIREWALL	= 0x8806000,	/* Firewalls */
 	SI_SUB_PROTO_IFATTACHDOMAIN = 0x8808000,/* domain dependent data init */