diff --git a/diskimage_builder/elements/modprobe/install.d/80-modprobe-blacklist b/diskimage_builder/elements/modprobe/install.d/80-modprobe-blacklist
index 6493726f8..b8b4ef7e7 100755
--- a/diskimage_builder/elements/modprobe/install.d/80-modprobe-blacklist
+++ b/diskimage_builder/elements/modprobe/install.d/80-modprobe-blacklist
@@ -6,7 +6,7 @@ fi
 set -eu
 set -o pipefail
 
-MODULES_LIST=${DIB_MODPROBE_BLACKLIST:?"Please set DIB_MODPROBE_BLACKLIST."}
+MODULES_LIST=${DIB_MODPROBE_BLACKLIST:-""}
 
 for mod_name in $MODULES_LIST; do
     echo "blacklist $mod_name" >> /etc/modprobe.d/blacklist.conf