Index: sys/dev/kbd/kbd.c
===================================================================
--- sys/dev/kbd/kbd.c
+++ sys/dev/kbd/kbd.c
@@ -70,7 +70,7 @@
 static	SLIST_HEAD(, keyboard_driver) keyboard_drivers =
 	SLIST_HEAD_INITIALIZER(keyboard_drivers);
 
-SET_DECLARE(kbddriver_set, const keyboard_driver_t);
+SET_DECLARE(kbddriver_set, keyboard_driver_t);
 
 /* local arrays */
 
@@ -159,23 +159,70 @@
 	kbd->kb_fkeytab_size = fkeymap_size;
 }
 
-/* declare a new keyboard driver */
-int
-kbd_add_driver(keyboard_driver_t *driver)
+/*
+ * kbd_add_driver_internal: declare a new keyboard driver.  This may be called
+ * up to twice for a given keyboard driver: once if it's built into the kernel,
+ * and again if it's also been declared as a module and it's built into the
+ * kernel.  The first call will always add the driver to the driver list, and
+ * the second call (post-linker set registration) will just mark the driver as
+ * officially registered so we reject any later calls.
+ */
+static int
+kbd_add_driver_internal(keyboard_driver_t *driver, bool linker_set)
 {
-	if (SLIST_NEXT(driver, link))
+
+	KASSERT(!linker_set || (driver->flags & KBDF_SET_REGISTERED) == 0,
+	    ("%s: double registration from linker set for '%s'",
+	    __func__, driver->name));
+	if ((driver->flags & KBDF_REGISTERED) != 0)
 		return (EINVAL);
+
+	/*
+	 * No further action required if the driver has already been registered
+	 * as a linker set driver.  Just mark it as fully registered and return,
+	 * it has already been added to the driver list in the first pass.
+	 */
+	if (!linker_set && (driver->flags & KBDF_SET_REGISTERED) != 0) {
+		driver->flags |= KBDF_REGISTERED;
+		return (0);
+	}
+
+	KASSERT(SLIST_NEXT(driver, link) == NULL,
+	    ("%s: keyboard driver list garbage detected", __func__));
 	if (driver->kbdsw->get_fkeystr == NULL)
 		driver->kbdsw->get_fkeystr = genkbd_get_fkeystr;
 	if (driver->kbdsw->diag == NULL)
 		driver->kbdsw->diag = genkbd_diag;
+
+	driver->flags |= (linker_set ? KBDF_SET_REGISTERED : KBDF_REGISTERED);
 	SLIST_INSERT_HEAD(&keyboard_drivers, driver, link);
 	return (0);
 }
 
+int
+kbd_add_driver(keyboard_driver_t *driver)
+{
+
+	return (kbd_add_driver_internal(driver, false));
+}
+
 int
 kbd_delete_driver(keyboard_driver_t *driver)
 {
+
+	/*
+	 * Imbalanced kbd_add_driver/kbd_delete_driver.  Technically one can
+	 * call kbd_delete_driver without having callded kbd_add_driver if
+	 * there's been some sort of error and the driver will not be
+	 * functional.  Most likely these will already have a matching
+	 * kbd_add_driver because they're processing module events and doing
+	 * setup along those lines.  We don't discriminate against in-kernel
+	 * only drivers that wish to unregister, though.
+	 */
+	if ((driver->flags & KBDF_REGISTRATION_MASK) == 0)
+		return (EINVAL);
+
+	driver->flags &= ~KBDF_REGISTRATION_MASK;
 	SLIST_REMOVE(&keyboard_drivers, driver, keyboard_driver, link);
 	SLIST_NEXT(driver, link) = NULL;
 	return (0);
@@ -185,7 +232,6 @@
 int
 kbd_register(keyboard_t *kbd)
 {
-	const keyboard_driver_t **list;
 	const keyboard_driver_t *p;
 	keyboard_t *mux;
 	keyboard_info_t ki;
@@ -226,23 +272,6 @@
 			return (index);
 		}
 	}
-	SET_FOREACH(list, kbddriver_set) {
-		p = *list;
-		if (strcmp(p->name, kbd->kb_name) == 0) {
-			kbd->kb_drv = p;
-			keyboard[index] = kbd;
-
-			if (mux != NULL) {
-				bzero(&ki, sizeof(ki));
-				strcpy(ki.kb_name, kbd->kb_name);
-				ki.kb_unit = kbd->kb_unit;
-
-				(void)kbdd_ioctl(mux, KBADDKBD, (caddr_t) &ki);
-			}
-
-			return (index);
-		}
-	}
 
 	return (-1);
 }
@@ -282,18 +311,12 @@
 keyboard_switch_t *
 kbd_get_switch(char *driver)
 {
-	const keyboard_driver_t **list;
 	const keyboard_driver_t *p;
 
 	SLIST_FOREACH(p, &keyboard_drivers, link) {
 		if (strcmp(p->name, driver) == 0)
 			return (p->kbdsw);
 	}
-	SET_FOREACH(list, kbddriver_set) {
-		p = *list;
-		if (strcmp(p->name, driver) == 0)
-			return (p->kbdsw);
-	}
 
 	return (NULL);
 }
@@ -435,18 +458,12 @@
 int
 kbd_configure(int flags)
 {
-	const keyboard_driver_t **list;
 	const keyboard_driver_t *p;
 
 	SLIST_FOREACH(p, &keyboard_drivers, link) {
 		if (p->configure != NULL)
 			(*p->configure)(flags);
 	}
-	SET_FOREACH(list, kbddriver_set) {
-		p = *list;
-		if (p->configure != NULL)
-			(*p->configure)(flags);
-	}
 
 	return (0);
 }
@@ -1510,16 +1527,19 @@
 static void
 kbd_drv_init(void)
 {
-	const keyboard_driver_t **list;
-	const keyboard_driver_t *p;
+	keyboard_driver_t *drv, **list;
 
 	SET_FOREACH(list, kbddriver_set) {
-		p = *list;
-		if (p->kbdsw->get_fkeystr == NULL)
-			p->kbdsw->get_fkeystr = genkbd_get_fkeystr;
-		if (p->kbdsw->diag == NULL)
-			p->kbdsw->diag = genkbd_diag;
+		drv = *list;
+
+		if (kbd_add_driver_internal(drv, true) != 0)
+			printf("kbd: failed to register driver '%s'\n",
+			    drv->name);
+		else if (bootverbose)
+			printf("kbd: registered driver '%s'\n",
+			    drv->name);
 	}
+
 }
 
 SYSINIT(kbd_drv_init, SI_SUB_DRIVERS, SI_ORDER_FIRST, kbd_drv_init, NULL);
Index: sys/dev/kbd/kbdreg.h
===================================================================
--- sys/dev/kbd/kbdreg.h
+++ sys/dev/kbd/kbdreg.h
@@ -107,8 +107,14 @@
     keyboard_switch_t * const	kbdsw;
     /* backdoor for the console driver */
     int				(* const configure)(int);
+    int				flags;
 } keyboard_driver_t;
 
+#define	KBDF_SET_REGISTERED	0x0001
+#define	KBDF_REGISTERED		0x0002
+
+#define	KBDF_REGISTRATION_MASK	(KBDF_SET_REGISTERED | KBDF_REGISTERED)
+
 /* keyboard */
 struct keyboard {
 	/* the following fields are managed by kbdio */