diff --git a/sys/conf/Makefile.alpha b/sys/conf/Makefile.alpha
index 51d69f6667ec..4f59a6e71ff1 100644
--- a/sys/conf/Makefile.alpha
+++ b/sys/conf/Makefile.alpha
@@ -276,13 +276,20 @@ kernel-install kernel-install.debug:
 		exit 1 ; \
 	fi
 .if exists(${DESTDIR}${KODIR})
-.if exists(${DESTDIR}${KODIR}.old)
-	@-chflags -R noschg ${DESTDIR}${KODIR}.old
-	-rm -rf ${DESTDIR}${KODIR}.old
-.endif
-	mv ${DESTDIR}${KODIR} ${DESTDIR}${KODIR}.old
-	[ "`sysctl -n kern.bootfile`" != "${DESTDIR}${KODIR}/kernel" ] || \
-		sysctl kern.bootfile=${DESTDIR}${KODIR}.old/kernel
+	-thiskernel=`sysctl -n kern.bootfile` ; \
+	if [ "$$thiskernel" = ${DESTDIR}${KODIR}.old/${KERNEL_KO} ] ; then \
+		chflags -R noschg ${DESTDIR}${KODIR} ; \
+		rm -rf ${DESTDIR}${KODIR} ; \
+	else \
+		if [ -d ${DESTDIR}${KODIR}.old ] ; then \
+			chflags -R noschg ${DESTDIR}${KODIR}.old ; \
+			rm -rf ${DESTDIR}${KODIR}.old ; \
+		fi ; \
+		mv ${DESTDIR}${KODIR} ${DESTDIR}${KODIR}.old ; \
+		if [ "$$thiskernel" = ${DESTDIR}${KODIR}/${KERNEL_KO} ] ; then \
+			sysctl -w kern.bootfile=${DESTDIR}${KODIR}.old/${KERNEL_KO} ; \
+		fi; \
+	fi
 .endif
 	mkdir -p ${DESTDIR}${KODIR}
 	install -c -m 555 -o root -g wheel \
diff --git a/sys/conf/Makefile.i386 b/sys/conf/Makefile.i386
index d9e1945362dd..0d72924e179a 100644
--- a/sys/conf/Makefile.i386
+++ b/sys/conf/Makefile.i386
@@ -234,13 +234,20 @@ kernel-install kernel-install.debug:
 		exit 1 ; \
 	fi
 .if exists(${DESTDIR}${KODIR})
-.if exists(${DESTDIR}${KODIR}.old)
-	@-chflags -R noschg ${DESTDIR}${KODIR}.old
-	-rm -rf ${DESTDIR}${KODIR}.old
-.endif
-	mv ${DESTDIR}${KODIR} ${DESTDIR}${KODIR}.old
-	[ "`sysctl -n kern.bootfile`" != "${DESTDIR}${KODIR}/kernel" ] || \
-		sysctl kern.bootfile=${DESTDIR}${KODIR}.old/kernel
+	-thiskernel=`sysctl -n kern.bootfile` ; \
+	if [ "$$thiskernel" = ${DESTDIR}${KODIR}.old/${KERNEL_KO} ] ; then \
+		chflags -R noschg ${DESTDIR}${KODIR} ; \
+		rm -rf ${DESTDIR}${KODIR} ; \
+	else \
+		if [ -d ${DESTDIR}${KODIR}.old ] ; then \
+			chflags -R noschg ${DESTDIR}${KODIR}.old ; \
+			rm -rf ${DESTDIR}${KODIR}.old ; \
+		fi ; \
+		mv ${DESTDIR}${KODIR} ${DESTDIR}${KODIR}.old ; \
+		if [ "$$thiskernel" = ${DESTDIR}${KODIR}/${KERNEL_KO} ] ; then \
+			sysctl -w kern.bootfile=${DESTDIR}${KODIR}.old/${KERNEL_KO} ; \
+		fi; \
+	fi
 .endif
 	mkdir -p ${DESTDIR}${KODIR}
 	install -c -m 555 -o root -g wheel \
diff --git a/sys/conf/Makefile.ia64 b/sys/conf/Makefile.ia64
index 0044e98ababb..6601f955cbb6 100644
--- a/sys/conf/Makefile.ia64
+++ b/sys/conf/Makefile.ia64
@@ -246,13 +246,20 @@ kernel-install kernel-install.debug:
 		exit 1 ; \
 	fi
 .if exists(${DESTDIR}${KODIR})
-.if exists(${DESTDIR}${KODIR}.old)
-	@-chflags -R noschg ${DESTDIR}${KODIR}.old
-	-rm -rf ${DESTDIR}${KODIR}.old
-.endif
-	mv ${DESTDIR}${KODIR} ${DESTDIR}${KODIR}.old
-	[ "`sysctl -n kern.bootfile`" != "${DESTDIR}${KODIR}/kernel" ] || \
-		sysctl kern.bootfile=${DESTDIR}${KODIR}.old/kernel
+	-thiskernel=`sysctl -n kern.bootfile` ; \
+	if [ "$$thiskernel" = ${DESTDIR}${KODIR}.old/${KERNEL_KO} ] ; then \
+		chflags -R noschg ${DESTDIR}${KODIR} ; \
+		rm -rf ${DESTDIR}${KODIR} ; \
+	else \
+		if [ -d ${DESTDIR}${KODIR}.old ] ; then \
+			chflags -R noschg ${DESTDIR}${KODIR}.old ; \
+			rm -rf ${DESTDIR}${KODIR}.old ; \
+		fi ; \
+		mv ${DESTDIR}${KODIR} ${DESTDIR}${KODIR}.old ; \
+		if [ "$$thiskernel" = ${DESTDIR}${KODIR}/${KERNEL_KO} ] ; then \
+			sysctl -w kern.bootfile=${DESTDIR}${KODIR}.old/${KERNEL_KO} ; \
+		fi; \
+	fi
 .endif
 	mkdir -p ${DESTDIR}${KODIR}
 	install -c -m 555 -o root -g wheel \
diff --git a/sys/conf/Makefile.pc98 b/sys/conf/Makefile.pc98
index 9990506e90ed..6237801ab0d5 100644
--- a/sys/conf/Makefile.pc98
+++ b/sys/conf/Makefile.pc98
@@ -237,13 +237,20 @@ kernel-install kernel-install.debug:
 		exit 1 ; \
 	fi
 .if exists(${DESTDIR}${KODIR})
-.if exists(${DESTDIR}${KODIR}.old)
-	@-chflags -R noschg ${DESTDIR}${KODIR}.old
-	-rm -rf ${DESTDIR}${KODIR}.old
-.endif
-	mv ${DESTDIR}${KODIR} ${DESTDIR}${KODIR}.old
-	[ "`sysctl -n kern.bootfile`" != "${DESTDIR}${KODIR}/kernel" ] || \
-		sysctl kern.bootfile=${DESTDIR}${KODIR}.old/kernel
+	-thiskernel=`sysctl -n kern.bootfile` ; \
+	if [ "$$thiskernel" = ${DESTDIR}${KODIR}.old/${KERNEL_KO} ] ; then \
+		chflags -R noschg ${DESTDIR}${KODIR} ; \
+		rm -rf ${DESTDIR}${KODIR} ; \
+	else \
+		if [ -d ${DESTDIR}${KODIR}.old ] ; then \
+			chflags -R noschg ${DESTDIR}${KODIR}.old ; \
+			rm -rf ${DESTDIR}${KODIR}.old ; \
+		fi ; \
+		mv ${DESTDIR}${KODIR} ${DESTDIR}${KODIR}.old ; \
+		if [ "$$thiskernel" = ${DESTDIR}${KODIR}/${KERNEL_KO} ] ; then \
+			sysctl -w kern.bootfile=${DESTDIR}${KODIR}.old/${KERNEL_KO} ; \
+		fi; \
+	fi
 .endif
 	mkdir -p ${DESTDIR}${KODIR}
 	install -c -m 555 -o root -g wheel \
diff --git a/sys/conf/Makefile.powerpc b/sys/conf/Makefile.powerpc
index 7543189f3bd5..3bd46c6621e3 100644
--- a/sys/conf/Makefile.powerpc
+++ b/sys/conf/Makefile.powerpc
@@ -243,13 +243,20 @@ kernel-install kernel-install.debug:
 		exit 1 ; \
 	fi
 .if exists(${DESTDIR}${KODIR})
-.if exists(${DESTDIR}${KODIR}.old)
-	@-chflags -R noschg ${DESTDIR}${KODIR}.old
-	-rm -rf ${DESTDIR}${KODIR}.old
-.endif
-	mv ${DESTDIR}${KODIR} ${DESTDIR}${KODIR}.old
-	[ "`sysctl -n kern.bootfile`" != "${DESTDIR}${KODIR}/kernel" ] || \
-		sysctl kern.bootfile=${DESTDIR}${KODIR}.old/kernel
+	-thiskernel=`sysctl -n kern.bootfile` ; \
+	if [ "$$thiskernel" = ${DESTDIR}${KODIR}.old/${KERNEL_KO} ] ; then \
+		chflags -R noschg ${DESTDIR}${KODIR} ; \
+		rm -rf ${DESTDIR}${KODIR} ; \
+	else \
+		if [ -d ${DESTDIR}${KODIR}.old ] ; then \
+			chflags -R noschg ${DESTDIR}${KODIR}.old ; \
+			rm -rf ${DESTDIR}${KODIR}.old ; \
+		fi ; \
+		mv ${DESTDIR}${KODIR} ${DESTDIR}${KODIR}.old ; \
+		if [ "$$thiskernel" = ${DESTDIR}${KODIR}/${KERNEL_KO} ] ; then \
+			sysctl -w kern.bootfile=${DESTDIR}${KODIR}.old/${KERNEL_KO} ; \
+		fi; \
+	fi
 .endif
 	mkdir -p ${DESTDIR}${KODIR}
 	install -c -m 555 -o root -g wheel \
diff --git a/sys/conf/Makefile.sparc64 b/sys/conf/Makefile.sparc64
index a1447b8e3654..3c9a1e6b2767 100644
--- a/sys/conf/Makefile.sparc64
+++ b/sys/conf/Makefile.sparc64
@@ -251,13 +251,20 @@ kernel-install kernel-install.debug:
 		exit 1 ; \
 	fi
 .if exists(${DESTDIR}${KODIR})
-.if exists(${DESTDIR}${KODIR}.old)
-	@-chflags -R noschg ${DESTDIR}${KODIR}.old
-	-rm -rf ${DESTDIR}${KODIR}.old
-.endif
-	mv ${DESTDIR}${KODIR} ${DESTDIR}${KODIR}.old
-	[ "`sysctl -n kern.bootfile`" != "${DESTDIR}${KODIR}/kernel" ] || \
-		sysctl kern.bootfile=${DESTDIR}${KODIR}.old/kernel
+	-thiskernel=`sysctl -n kern.bootfile` ; \
+	if [ "$$thiskernel" = ${DESTDIR}${KODIR}.old/${KERNEL_KO} ] ; then \
+		chflags -R noschg ${DESTDIR}${KODIR} ; \
+		rm -rf ${DESTDIR}${KODIR} ; \
+	else \
+		if [ -d ${DESTDIR}${KODIR}.old ] ; then \
+			chflags -R noschg ${DESTDIR}${KODIR}.old ; \
+			rm -rf ${DESTDIR}${KODIR}.old ; \
+		fi ; \
+		mv ${DESTDIR}${KODIR} ${DESTDIR}${KODIR}.old ; \
+		if [ "$$thiskernel" = ${DESTDIR}${KODIR}/${KERNEL_KO} ] ; then \
+			sysctl -w kern.bootfile=${DESTDIR}${KODIR}.old/${KERNEL_KO} ; \
+		fi; \
+	fi
 .endif
 	mkdir -p ${DESTDIR}${KODIR}
 	install -c -m 555 -o root -g wheel \