diff --git a/sys/conf/files b/sys/conf/files
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -4481,7 +4481,6 @@
 netipsec/xform_tcp.c		optional ipsec inet tcp_signature | \
 	 ipsec inet6 tcp_signature | ipsec_support inet tcp_signature | \
 	 ipsec_support inet6 tcp_signature
-netlink/netlink_generic_kpi.c	standard
 netlink/netlink_glue.c		standard
 netlink/netlink_message_parser.c	standard
 netlink/netlink_domain.c	optional netlink
diff --git a/sys/netlink/netlink_ctl.h b/sys/netlink/netlink_ctl.h
--- a/sys/netlink/netlink_ctl.h
+++ b/sys/netlink/netlink_ctl.h
@@ -92,7 +92,7 @@
 	uint32_t	cmd_num;
 };
 
-uint32_t genl_register_family(const char *family_name, size_t hdrsize,
+uint16_t genl_register_family(const char *family_name, size_t hdrsize,
     uint16_t family_version, uint16_t max_attr_idx);
 bool genl_unregister_family(const char *family_name);
 bool genl_register_cmds(const char *family_name, const struct genl_cmd *cmds,
diff --git a/sys/netlink/netlink_generic.c b/sys/netlink/netlink_generic.c
--- a/sys/netlink/netlink_generic.c
+++ b/sys/netlink/netlink_generic.c
@@ -119,7 +119,7 @@
 	ghdr_new->reserved = 0;
 
         nlattr_add_string(nw, CTRL_ATTR_FAMILY_NAME, gf->family_name);
-        nlattr_add_u16(nw, CTRL_ATTR_FAMILY_ID, gf->family_id);
+        nlattr_add_u16(nw, CTRL_ATTR_FAMILY_ID, genl_get_family_id(gf));
         nlattr_add_u32(nw, CTRL_ATTR_VERSION, gf->family_version);
         nlattr_add_u32(nw, CTRL_ATTR_HDRSIZE, gf->family_hdrsize);
         nlattr_add_u32(nw, CTRL_ATTR_MAXATTR, gf->family_attr_max);
@@ -173,9 +173,6 @@
 static void nlctrl_notify(void *arg, const struct genl_family *gf, int action);
 static eventhandler_tag family_event_tag;
 
-static uint32_t ctrl_family_id;
-static uint32_t ctrl_group_id;
-
 struct nl_parsed_family {
 	uint32_t	family_id;
 	char		*family_name;
@@ -201,7 +198,7 @@
 {
 	if (gf->family_name == NULL)
 		return (false);
-	if (attrs->family_id != 0 && attrs->family_id != gf->family_id)
+	if (attrs->family_id != 0 && attrs->family_id != genl_get_family_id(gf))
 		return (false);
 	if (attrs->family_name != NULL && strcmp(attrs->family_name, gf->family_name))
 		return (false);
@@ -259,7 +256,7 @@
 	struct genlmsghdr ghdr = { .cmd = cmd };
 	struct nl_writer nw;
 
-	if (!nl_writer_group(&nw, NLMSG_SMALL, NETLINK_GENERIC, ctrl_group_id,
+	if (!nl_writer_group(&nw, NLMSG_SMALL, NETLINK_GENERIC, CTRL_GROUP_ID,
 	    0, false)) {
 		NL_LOG(LOG_DEBUG, "error allocating group writer");
 		return;
@@ -269,27 +266,16 @@
 	nlmsg_flush(&nw);
 }
 
-static const struct genl_cmd nlctrl_cmds[] = {
-	{
-		.cmd_num = CTRL_CMD_GETFAMILY,
-		.cmd_name = "GETFAMILY",
-		.cmd_cb = nlctrl_handle_getfamily,
-		.cmd_flags = GENL_CMD_CAP_DO | GENL_CMD_CAP_DUMP | GENL_CMD_CAP_HASPOL,
-	},
-};
-
 static const struct nlhdr_parser *all_parsers[] = { &genl_parser };
 
 static void
 genl_load_all(void *u __unused)
 {
 	NL_VERIFY_PARSERS(all_parsers);
-	ctrl_family_id = genl_register_family(CTRL_FAMILY_NAME, 0, 2, CTRL_ATTR_MAX);
-	genl_register_cmds(CTRL_FAMILY_NAME, nlctrl_cmds, nitems(nlctrl_cmds));
-	ctrl_group_id = genl_register_group(CTRL_FAMILY_NAME, "notify");
-	family_event_tag = EVENTHANDLER_REGISTER(genl_family_event, nlctrl_notify, NULL,
-	    EVENTHANDLER_PRI_ANY);
-	netlink_register_proto(NETLINK_GENERIC, "NETLINK_GENERIC", genl_handle_message);
+	family_event_tag = EVENTHANDLER_REGISTER(genl_family_event,
+	    nlctrl_notify, NULL, EVENTHANDLER_PRI_ANY);
+	netlink_register_proto(NETLINK_GENERIC, "NETLINK_GENERIC",
+	    genl_handle_message);
 }
 SYSINIT(genl_load_all, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, genl_load_all, NULL);
 
@@ -298,7 +284,268 @@
 {
 	netlink_unregister_proto(NETLINK_GENERIC);
 	EVENTHANDLER_DEREGISTER(genl_family_event, family_event_tag);
-	genl_unregister_family(CTRL_FAMILY_NAME);
 	NET_EPOCH_WAIT();
 }
 SYSUNINIT(genl_unload, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, genl_unload, NULL);
+
+/*
+ * Public KPI for NETLINK_GENERIC families/groups registration logic below.
+ */
+
+static struct sx sx_lock;
+SX_SYSINIT(genl_lock, &sx_lock, "genetlink lock");
+#define	GENL_LOCK()		sx_xlock(&sx_lock)
+#define	GENL_UNLOCK()		sx_xunlock(&sx_lock)
+#define	GENL_ASSERT_LOCKED()	sx_assert(&sx_lock, SA_LOCKED)
+#define	GENL_ASSERT_XLOCKED()	sx_assert(&sx_lock, SA_XLOCKED)
+
+static struct genl_cmd nlctrl_cmds[] = {
+	[CTRL_CMD_GETFAMILY] = {
+		.cmd_num = CTRL_CMD_GETFAMILY,
+		.cmd_name = "GETFAMILY",
+		.cmd_cb = nlctrl_handle_getfamily,
+		.cmd_flags = GENL_CMD_CAP_DO | GENL_CMD_CAP_DUMP |
+		    GENL_CMD_CAP_HASPOL,
+	},
+};
+
+static struct genl_family families[MAX_FAMILIES] = {
+	[CTRL_FAMILY_ID] = {
+		.family_name = CTRL_FAMILY_NAME,
+		.family_hdrsize = 0,
+		.family_version = 2,
+		.family_attr_max = CTRL_ATTR_MAX,
+		.family_cmd_size = CTRL_CMD_GETFAMILY + 1,
+		.family_cmds = nlctrl_cmds,
+		.family_num_groups = 1,
+	},
+}
+;
+static struct genl_group groups[MAX_GROUPS] = {
+	[CTRL_GROUP_ID] = {
+		.group_family = &families[CTRL_FAMILY_ID],
+		.group_name = CTRL_GROUP_NAME,
+	},
+};
+
+static struct genl_family *
+find_family(const char *family_name)
+{
+	GENL_ASSERT_LOCKED();
+	for (u_int i = 0; i < MAX_FAMILIES; i++)
+		if (families[i].family_name != NULL &&
+		    strcmp(families[i].family_name, family_name) == 0)
+			return (&families[i]);
+
+	return (NULL);
+}
+
+static struct genl_family *
+find_empty_family_id(const char *family_name)
+{
+	GENL_ASSERT_LOCKED();
+	/* Microoptimization: index 0 is reserved for the control family */
+	for (u_int i = 1; i < MAX_FAMILIES; i++)
+		if (families[i].family_name == NULL)
+			return (&families[i]);
+
+	return (NULL);
+}
+
+uint16_t
+genl_register_family(const char *family_name, size_t hdrsize,
+    uint16_t family_version, uint16_t max_attr_idx)
+{
+	struct genl_family *gf;
+	uint16_t family_id;
+
+	GENL_LOCK();
+	if (find_family(family_name) != NULL) {
+		GENL_UNLOCK();
+		return (0);
+	}
+
+	gf = find_empty_family_id(family_name);
+	KASSERT(gf, ("%s: maximum of %u generic netlink families allocated",
+	    __func__, MAX_FAMILIES));
+
+	*gf = (struct genl_family) {
+	    .family_name = family_name,
+	    .family_version = family_version,
+	    .family_hdrsize = hdrsize,
+	    .family_attr_max = max_attr_idx,
+	};
+	family_id = genl_get_family_id(gf);
+	GENL_UNLOCK();
+
+	NL_LOG(LOG_DEBUG2, "Registered family %s id %d", gf->family_name,
+	    family_id);
+	EVENTHANDLER_INVOKE(genl_family_event, gf, CTRL_CMD_NEWFAMILY);
+
+	return (family_id);
+}
+
+static void
+free_family(struct genl_family *gf)
+{
+	if (gf->family_cmds != NULL)
+		free(gf->family_cmds, M_NETLINK);
+}
+
+/*
+ * unregister groups of a given family
+ */
+static void
+unregister_groups(const struct genl_family *gf)
+{
+
+	for (u_int i = 0; i < MAX_GROUPS; i++) {
+		struct genl_group *gg = &groups[i];
+		if (gg->group_family == gf && gg->group_name != NULL) {
+			gg->group_family = NULL;
+			gg->group_name = NULL;
+		}
+	}
+}
+
+/*
+ * Can sleep, I guess
+ */
+bool
+genl_unregister_family(const char *family_name)
+{
+	bool found = false;
+
+	GENL_LOCK();
+	struct genl_family *gf = find_family(family_name);
+
+	if (gf != NULL) {
+		EVENTHANDLER_INVOKE(genl_family_event, gf, CTRL_CMD_DELFAMILY);
+		found = true;
+		unregister_groups(gf);
+		/* TODO: zero pointer first */
+		free_family(gf);
+		bzero(gf, sizeof(*gf));
+	}
+	GENL_UNLOCK();
+
+	return (found);
+}
+
+bool
+genl_register_cmds(const char *family_name, const struct genl_cmd *cmds,
+    int count)
+{
+	struct genl_family *gf;
+	uint16_t cmd_size;
+
+	GENL_LOCK();
+	if ((gf = find_family(family_name)) == NULL) {
+		GENL_UNLOCK();
+		return (false);
+	}
+
+	cmd_size = gf->family_cmd_size;
+
+	for (u_int i = 0; i < count; i++) {
+		MPASS(cmds[i].cmd_cb != NULL);
+		if (cmds[i].cmd_num >= cmd_size)
+			cmd_size = cmds[i].cmd_num + 1;
+	}
+
+	if (cmd_size > gf->family_cmd_size) {
+		void *old_data;
+
+		/* need to realloc */
+		size_t sz = cmd_size * sizeof(struct genl_cmd);
+		void *data = malloc(sz, M_NETLINK, M_WAITOK | M_ZERO);
+
+		memcpy(data, gf->family_cmds,
+		    gf->family_cmd_size * sizeof(struct genl_cmd));
+		old_data = gf->family_cmds;
+		gf->family_cmds = data;
+		gf->family_cmd_size = cmd_size;
+		free(old_data, M_NETLINK);
+	}
+
+	for (u_int i = 0; i < count; i++) {
+		const struct genl_cmd *cmd = &cmds[i];
+
+		MPASS(gf->family_cmds[cmd->cmd_num].cmd_cb == NULL);
+		gf->family_cmds[cmd->cmd_num] = cmds[i];
+		NL_LOG(LOG_DEBUG2, "Adding cmd %s(%d) to family %s",
+		    cmd->cmd_name, cmd->cmd_num, gf->family_name);
+	}
+	GENL_UNLOCK();
+	return (true);
+}
+
+static struct genl_group *
+find_group(const struct genl_family *gf, const char *group_name)
+{
+	for (u_int i = 0; i < MAX_GROUPS; i++) {
+		struct genl_group *gg = &groups[i];
+		if (gg->group_family == gf &&
+		    !strcmp(gg->group_name, group_name))
+			return (gg);
+	}
+	return (NULL);
+}
+
+uint32_t
+genl_register_group(const char *family_name, const char *group_name)
+{
+	struct genl_family *gf;
+	uint32_t group_id = 0;
+
+	MPASS(family_name != NULL);
+	MPASS(group_name != NULL);
+
+	GENL_LOCK();
+	if ((gf = find_family(family_name)) == NULL ||
+	    find_group(gf, group_name) != NULL) {
+		GENL_UNLOCK();
+		return (0);
+	}
+
+	/* Microoptimization: index 0 is reserved for the control family */
+	for (u_int i = 1; i < MAX_GROUPS; i++) {
+		struct genl_group *gg = &groups[i];
+		if (gg->group_family == NULL) {
+			gf->family_num_groups++;
+			gg->group_family = gf;
+			gg->group_name = group_name;
+			group_id = i + MIN_GROUP_NUM;
+			break;
+		}
+	}
+	GENL_UNLOCK();
+
+	return (group_id);
+}
+
+/* accessors */
+struct genl_family *
+genl_get_family(uint16_t family_id)
+{
+	return ((family_id < MAX_FAMILIES) ? &families[family_id] : NULL);
+}
+
+const char *
+genl_get_family_name(const struct genl_family *gf)
+{
+	return (gf->family_name);
+}
+
+uint16_t
+genl_get_family_id(const struct genl_family *gf)
+{
+	MPASS(gf >= &families[0] && gf < &families[MAX_FAMILIES]);
+	return ((uint16_t)(gf - &families[0]) + GENL_MIN_ID);
+}
+
+struct genl_group *
+genl_get_group(uint32_t group_id)
+{
+	return ((group_id < MAX_GROUPS) ? &groups[group_id] : NULL);
+}
diff --git a/sys/netlink/netlink_generic_kpi.c b/sys/netlink/netlink_generic_kpi.c
deleted file mode 100644
--- a/sys/netlink/netlink_generic_kpi.c
+++ /dev/null
@@ -1,276 +0,0 @@
-/*-
- * SPDX-License-Identifier: BSD-2-Clause
- *
- * Copyright (c) 2022 Alexander V. Chernikov <melifaro@FreeBSD.org>
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#include <sys/types.h>
-#include <sys/ck.h>
-#include <sys/epoch.h>
-#include <sys/eventhandler.h>
-#include <sys/kernel.h>
-#include <sys/lock.h>
-#include <sys/malloc.h>
-#include <sys/socket.h>
-#include <sys/sx.h>
-
-#include <netlink/netlink.h>
-#include <netlink/netlink_ctl.h>
-#include <netlink/netlink_generic.h>
-#include <netlink/netlink_var.h>
-
-#define	DEBUG_MOD_NAME	nl_generic_kpi
-#define	DEBUG_MAX_LEVEL	LOG_DEBUG3
-#include <netlink/netlink_debug.h>
-_DECLARE_DEBUG(LOG_INFO);
-
-
-/*
- * NETLINK_GENERIC families/groups registration logic
- */
-
-#define	GENL_LOCK()		sx_xlock(&sx_lock)
-#define	GENL_UNLOCK()		sx_xunlock(&sx_lock)
-static struct sx sx_lock;
-SX_SYSINIT(genl_lock, &sx_lock, "genetlink lock");
-
-static struct genl_family	families[MAX_FAMILIES];
-static struct genl_group	groups[MAX_GROUPS];
-
-static struct genl_family *
-find_family(const char *family_name)
-{
-	for (int i = 0; i < MAX_FAMILIES; i++) {
-		struct genl_family *gf = &families[i];
-		if (gf->family_name != NULL && !strcmp(gf->family_name, family_name))
-			return (gf);
-	}
-
-	return (NULL);
-}
-
-static struct genl_family *
-find_empty_family_id(const char *family_name)
-{
-	struct genl_family *gf = NULL;
-
-	if (!strcmp(family_name, CTRL_FAMILY_NAME)) {
-		gf = &families[0];
-		gf->family_id = GENL_MIN_ID;
-	} else {
-		/* Index 0 is reserved for the control family */
-		for (int i = 1; i < MAX_FAMILIES; i++) {
-			gf = &families[i];
-			if (gf->family_name == NULL) {
-				gf->family_id = GENL_MIN_ID + i;
-				break;
-			}
-		}
-	}
-
-	return (gf);
-}
-
-uint32_t
-genl_register_family(const char *family_name, size_t hdrsize,
-    uint16_t family_version, uint16_t max_attr_idx)
-{
-
-	MPASS(family_name != NULL);
-	if (find_family(family_name) != NULL)
-		return (0);
-
-	GENL_LOCK();
-
-	struct genl_family *gf = find_empty_family_id(family_name);
-	MPASS(gf != NULL);
-
-	gf->family_name = family_name;
-	gf->family_version = family_version;
-	gf->family_hdrsize = hdrsize;
-	gf->family_attr_max = max_attr_idx;
-	NL_LOG(LOG_DEBUG2, "Registered family %s id %d", gf->family_name,
-	    gf->family_id);
-	EVENTHANDLER_INVOKE(genl_family_event, gf, CTRL_CMD_NEWFAMILY);
-
-	GENL_UNLOCK();
-
-	return (gf->family_id);
-}
-
-static void
-free_family(struct genl_family *gf)
-{
-	if (gf->family_cmds != NULL)
-		free(gf->family_cmds, M_NETLINK);
-}
-
-/*
- * unregister groups of a given family
- */
-static void
-unregister_groups(const struct genl_family *gf)
-{
-
-	for (int i = 0; i < MAX_GROUPS; i++) {
-		struct genl_group *gg = &groups[i];
-		if (gg->group_family == gf && gg->group_name != NULL) {
-			gg->group_family = NULL;
-			gg->group_name = NULL;
-		}
-	}
-}
-
-/*
- * Can sleep, I guess
- */
-bool
-genl_unregister_family(const char *family_name)
-{
-	bool found = false;
-
-	GENL_LOCK();
-	struct genl_family *gf = find_family(family_name);
-
-	if (gf != NULL) {
-		EVENTHANDLER_INVOKE(genl_family_event, gf, CTRL_CMD_DELFAMILY);
-		found = true;
-		unregister_groups(gf);
-		/* TODO: zero pointer first */
-		free_family(gf);
-		bzero(gf, sizeof(*gf));
-	}
-	GENL_UNLOCK();
-
-	return (found);
-}
-
-bool
-genl_register_cmds(const char *family_name, const struct genl_cmd *cmds, int count)
-{
-	GENL_LOCK();
-	struct genl_family *gf = find_family(family_name);
-	if (gf == NULL) {
-		GENL_UNLOCK();
-		return (false);
-	}
-
-	int cmd_size = gf->family_cmd_size;
-
-	for (int i = 0; i < count; i++) {
-		MPASS(cmds[i].cmd_cb != NULL);
-		if (cmds[i].cmd_num >= cmd_size)
-			cmd_size = cmds[i].cmd_num + 1;
-	}
-
-	if (cmd_size > gf->family_cmd_size) {
-		/* need to realloc */
-		size_t sz = cmd_size * sizeof(struct genl_cmd);
-		void *data = malloc(sz, M_NETLINK, M_WAITOK | M_ZERO);
-
-		memcpy(data, gf->family_cmds, gf->family_cmd_size * sizeof(struct genl_cmd));
-		void *old_data = gf->family_cmds;
-		gf->family_cmds = data;
-		gf->family_cmd_size = cmd_size;
-		free(old_data, M_NETLINK);
-	}
-
-	for (int i = 0; i < count; i++) {
-		const struct genl_cmd *cmd = &cmds[i];
-		MPASS(gf->family_cmds[cmd->cmd_num].cmd_cb == NULL);
-		gf->family_cmds[cmd->cmd_num] = cmds[i];
-		NL_LOG(LOG_DEBUG2, "Adding cmd %s(%d) to family %s",
-		    cmd->cmd_name, cmd->cmd_num, gf->family_name);
-	}
-	GENL_UNLOCK();
-	return (true);
-}
-
-static struct genl_group *
-find_group(const struct genl_family *gf, const char *group_name)
-{
-	for (int i = 0; i < MAX_GROUPS; i++) {
-		struct genl_group *gg = &groups[i];
-		if (gg->group_family == gf && !strcmp(gg->group_name, group_name))
-			return (gg);
-	}
-	return (NULL);
-}
-
-uint32_t
-genl_register_group(const char *family_name, const char *group_name)
-{
-	uint32_t group_id = 0;
-
-	MPASS(family_name != NULL);
-	MPASS(group_name != NULL);
-
-	GENL_LOCK();
-	struct genl_family *gf = find_family(family_name);
-
-	if (gf == NULL || find_group(gf, group_name) != NULL) {
-		GENL_UNLOCK();
-		return (0);
-	}
-
-	for (int i = 0; i < MAX_GROUPS; i++) {
-		struct genl_group *gg = &groups[i];
-		if (gg->group_family == NULL) {
-			gf->family_num_groups++;
-			gg->group_family = gf;
-			gg->group_name = group_name;
-			group_id = i + MIN_GROUP_NUM;
-			break;
-		}
-	}
-	GENL_UNLOCK();
-
-	return (group_id);
-}
-
-/* accessors */
-struct genl_family *
-genl_get_family(uint16_t family_id)
-{
-	return ((family_id < MAX_FAMILIES) ? &families[family_id] : NULL);
-}
-
-const char *
-genl_get_family_name(const struct genl_family *gf)
-{
-	return (gf->family_name);
-}
-
-uint16_t
-genl_get_family_id(const struct genl_family *gf)
-{
-	return (gf->family_id);
-}
-
-struct genl_group *
-genl_get_group(uint32_t group_id)
-{
-	return ((group_id < MAX_GROUPS) ? &groups[group_id] : NULL);
-}
-
diff --git a/sys/netlink/netlink_var.h b/sys/netlink/netlink_var.h
--- a/sys/netlink/netlink_var.h
+++ b/sys/netlink/netlink_var.h
@@ -147,7 +147,6 @@
 struct genl_family {
 	const char	*family_name;
 	uint16_t	family_hdrsize;
-	uint16_t	family_id;
 	uint16_t	family_version;
 	uint16_t	family_attr_max;
 	uint16_t	family_cmd_size;
@@ -168,7 +167,10 @@
 
 #define	MIN_GROUP_NUM	48
 
+#define	CTRL_FAMILY_ID		0
 #define	CTRL_FAMILY_NAME	"nlctrl"
+#define	CTRL_GROUP_ID		0
+#define	CTRL_GROUP_NAME		"notify"
 
 struct ifnet;
 struct nl_parsed_link;