diff --git a/check b/check
index d2e5129620bd630cdf75a6dcd1ac1457cedb14dc..43212dc7b80f7ff767340a936f9e4ed4eb3920fb 100755
--- a/check
+++ b/check
@@ -283,6 +283,7 @@ while [ $# -gt 0 ]; do
 		FSTYP="${1:1}"
 		;;
 	-overlay)
+		[ "$FSTYP" == overlay ] || export OVL_BASE_FSTYP="$FSTYP"
 		FSTYP=overlay
 		export OVERLAY=true
 		;;
diff --git a/common/overlay b/common/overlay
index e35419d0e0452a18e93a88dc5b255345a687e4ea..20cafeb157b1a50b80ec298dc80a2e1e1a37ff87 100644
--- a/common/overlay
+++ b/common/overlay
@@ -85,7 +85,12 @@ _overlay_base_mount()
 		return 1
 	fi
 
-	_mount -t $OVL_BASE_FSTYP $* $dev $mnt
+	if [ $OVL_BASE_FSTYP ]; then
+		_mount -t $OVL_BASE_FSTYP $* $dev $mnt
+	else
+		_mount $* $dev $mnt
+	fi
+
 	_idmapped_mount $dev $mnt
 }