--- trunk/installer-simple/functions/hwdetection.sh	2014/01/07 13:24:37	2407
+++ trunk/installer-simple/functions/hwdetection.sh	2014/01/07 13:25:22	2408
@@ -315,17 +315,38 @@
 	${chroot} mkinitrd -f ${initrd} ${kernel}
 }
 
+is_mounted()
+{
+	local item
+	local mount
+	local method
+	method="$1"
+	item="$2"
+
+	[ -e /proc/mounts ] || return 1
+
+	case ${method} in
+		--location) mount="$(grep "[[:space:]]${item}[[:space:]]" /proc/mounts | cut -d ' ' -f2)" ;;
+		--device) mount="$(grep "^${item}[[:space:]]" /proc/mounts | cut -d ' ' -f1)" ;;
+		--filesystem) mount="$(grep "[[:space:]]${item}[[:space:]]" /proc/mounts | cut -d ' ' -f3)" ;;
+		*) echo "unknown method '${method}'"; return 1 ;;
+	esac
+	[[ ${mount} != ${item} ]] && return 1
+
+	return 0
+}
+
 chrooted()
 {
 	local cmd="$@"
 
-	mount -t sysfs sysfs ${INSTALL_ROOT}/sys
-	mount -t proc proc ${INSTALL_ROOT}/proc
-	mount -o bind /dev ${INSTALL_ROOT}/dev
-
-	chroot ${INSTALL_ROOT} ${cmd}
-
-	umount ${INSTALL_ROOT}/dev
-	umount ${INSTALL_ROOT}/proc
-	umount ${INSTALL_ROOT}/sys
+	is_mounted --location ${INSTALLROOT}/sys || mount -t sysfs sysfs ${INSTALLROOT}/sys
+	is_mounted --location ${INSTALLROOT}/proc || mount -t proc proc ${INSTALLROOT}/proc
+	is_mounted --location ${INSTALLROOT}/dev || mount -o bind /dev ${INSTALLROOT}/dev
+
+	chroot ${INSTALLROOT} ${cmd}
+
+	is_mounted --location ${INSTALLROOT}/dev && umount ${INSTALLROOT}/dev
+	is_mounted --location ${INSTALLROOT}/proc && umount ${INSTALLROOT}/proc
+	is_mounted --location ${INSTALLROOT}/sys && umount ${INSTALLROOT}/sys
 }