diff --git a/sys/alpha/alpha/autoconf.c b/sys/alpha/alpha/autoconf.c
index d3ffb233a07e..d467ef79ac63 100644
--- a/sys/alpha/alpha/autoconf.c
+++ b/sys/alpha/alpha/autoconf.c
@@ -29,8 +29,6 @@ __FBSDID("$FreeBSD$");
 
 #include "opt_bootp.h"
 #include "opt_isa.h"
-#include "opt_nfs.h"
-#include "opt_nfsroot.h"
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -67,8 +65,6 @@ static void	configure_start(void);
 device_t isa_bus_device = 0;
 #endif
 
-extern int nfs_diskless_valid;		/* XXX use include file */
-
 static void
 configure_start()
 {
@@ -194,20 +190,3 @@ configure(void *dummy)
 
 	cold = 0;
 }
-
-/*
- * Do legacy root filesystem discovery.  This isn't really
- * needed on the Alpha, which has always used the loader.
- */
-void
-cpu_rootconf()
-{
-#if defined(NFSCLIENT) && defined(NFS_ROOT)
-	int	order = 0;
-#if !defined(BOOTP_NFSROOT)
-	if (nfs_diskless_valid)
-#endif
-		rootdevnames[order++] = "nfs:";
-#endif
-}
-SYSINIT(cpu_rootconf, SI_SUB_ROOT_CONF, SI_ORDER_FIRST, cpu_rootconf, NULL)
diff --git a/sys/amd64/amd64/autoconf.c b/sys/amd64/amd64/autoconf.c
index c646741c0412..f638bc83b659 100644
--- a/sys/amd64/amd64/autoconf.c
+++ b/sys/amd64/amd64/autoconf.c
@@ -45,8 +45,6 @@ __FBSDID("$FreeBSD$");
  */
 #include "opt_bootp.h"
 #include "opt_isa.h"
-#include "opt_nfs.h"
-#include "opt_nfsroot.h"
 #include "opt_bus.h"
 
 #include <sys/param.h>
@@ -66,10 +64,6 @@ __FBSDID("$FreeBSD$");
 #include <net/if_var.h>
 #include <net/ethernet.h>
 #include <netinet/in.h>
-#include <nfs/rpcv2.h>
-#include <nfs/nfsproto.h>
-#include <nfsclient/nfs.h>
-#include <nfsclient/nfsdiskless.h>
 
 #include <machine/md_var.h>
 
@@ -136,22 +130,3 @@ configure_final(dummy)
 		printf("Device configuration finished.\n");
 	cold = 0;
 }
-
-/*
- * Do legacy root filesystem discovery.
- */
-void
-cpu_rootconf()
-{
-#ifdef BOOTP
-        bootpc_init();
-#endif
-#if defined(NFSCLIENT) && defined(NFS_ROOT)
-#if !defined(BOOTP_NFSROOT)
-	nfs_setup_diskless();
-	if (nfs_diskless_valid)
-#endif
-		rootdevnames[0] = "nfs:";
-#endif
-}
-SYSINIT(cpu_rootconf, SI_SUB_ROOT_CONF, SI_ORDER_FIRST, cpu_rootconf, NULL)
diff --git a/sys/i386/i386/autoconf.c b/sys/i386/i386/autoconf.c
index c213a68549a1..c4eca30d918e 100644
--- a/sys/i386/i386/autoconf.c
+++ b/sys/i386/i386/autoconf.c
@@ -45,8 +45,6 @@ __FBSDID("$FreeBSD$");
  */
 #include "opt_bootp.h"
 #include "opt_isa.h"
-#include "opt_nfs.h"
-#include "opt_nfsroot.h"
 #include "opt_bus.h"
 
 #include <sys/param.h>
@@ -66,10 +64,6 @@ __FBSDID("$FreeBSD$");
 #include <net/if_var.h>
 #include <net/ethernet.h>
 #include <netinet/in.h>
-#include <nfs/rpcv2.h>
-#include <nfs/nfsproto.h>
-#include <nfsclient/nfs.h>
-#include <nfsclient/nfsdiskless.h>
 
 #include <machine/bootinfo.h>
 #include <machine/md_var.h>
@@ -174,22 +168,3 @@ configure_final(dummy)
 	}
 	cold = 0;
 }
-
-/*
- * Do legacy root filesystem discovery.
- */
-void
-cpu_rootconf()
-{
-#ifdef BOOTP
-        bootpc_init();
-#endif
-#if defined(NFSCLIENT) && defined(NFS_ROOT)
-#if !defined(BOOTP_NFSROOT)
-	nfs_setup_diskless();
-	if (nfs_diskless_valid)
-#endif
-		rootdevnames[0] = "nfs:";
-#endif
-}
-SYSINIT(cpu_rootconf, SI_SUB_ROOT_CONF, SI_ORDER_FIRST, cpu_rootconf, NULL)
diff --git a/sys/ia64/ia64/autoconf.c b/sys/ia64/ia64/autoconf.c
index dcfd1b04dfde..0772acca82c3 100644
--- a/sys/ia64/ia64/autoconf.c
+++ b/sys/ia64/ia64/autoconf.c
@@ -28,8 +28,6 @@
 
 #include "opt_bootp.h"
 #include "opt_isa.h"
-#include "opt_nfs.h"
-#include "opt_nfsroot.h"
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -63,8 +61,6 @@ void bootpc_init(void);
 device_t isa_bus_device = 0;
 #endif
 
-extern int nfs_diskless_valid;		/* XXX use include file */
-
 /*
  * Determine i/o configuration for a machine.
  */
@@ -91,26 +87,3 @@ configure(void *dummy)
 
 	cold = 0;
 }
-
-/*
- * Do legacy root filesystem discovery.  This isn't really
- * needed on the Alpha, which has always used the loader.
- */
-void
-cpu_rootconf()
-{
-#if defined(NFSCLIENT) && defined(NFS_ROOT)
-	int	order = 0;
-#endif
-
-#ifdef BOOTP
-	bootpc_init();
-#endif
-#if defined(NFSCLIENT) && defined(NFS_ROOT)
-#if !defined(BOOTP_NFSROOT)
-	if (nfs_diskless_valid)
-#endif
-		rootdevnames[order++] = "nfs:";
-#endif
-}
-SYSINIT(cpu_rootconf, SI_SUB_ROOT_CONF, SI_ORDER_FIRST, cpu_rootconf, NULL)
diff --git a/sys/nfsclient/bootp_subr.c b/sys/nfsclient/bootp_subr.c
index 2132ef581689..bdc98d2fbd7c 100644
--- a/sys/nfsclient/bootp_subr.c
+++ b/sys/nfsclient/bootp_subr.c
@@ -1740,6 +1740,7 @@ bootpc_init(void)
 #endif
 	}
 
+	rootdevnames[0] = "nfs:";
 	mountopts(&nd->root_args, NULL);
 
 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next)
@@ -1894,3 +1895,5 @@ out:
 	m_freem(m);
 	return error;
 }
+
+SYSINIT(bootp_rootconf, SI_SUB_ROOT_CONF, SI_ORDER_FIRST, bootpc_init, NULL);
diff --git a/sys/nfsclient/nfs_diskless.c b/sys/nfsclient/nfs_diskless.c
index 51b34d3c6b7f..212a1650632b 100644
--- a/sys/nfsclient/nfs_diskless.c
+++ b/sys/nfsclient/nfs_diskless.c
@@ -231,3 +231,17 @@ decode_nfshandle(char *ev, u_char *fh)
 		}
 	}
 }
+
+#if !defined(BOOTP_NFSROOT)
+static void
+nfs_rootconf(void)
+{
+
+	nfs_setup_diskless();
+	if (nfs_diskless_valid)
+		rootdevnames[0] = "nfs:";
+}
+
+SYSINIT(cpu_rootconf, SI_SUB_ROOT_CONF, SI_ORDER_FIRST, nfs_rootconf, NULL)
+#endif
+