diff --git a/conf/distro/poky-raspberrypi.conf b/conf/distro/poky-raspberrypi.conf
index f0e16bc..a361035 100644
--- a/conf/distro/poky-raspberrypi.conf
+++ b/conf/distro/poky-raspberrypi.conf
@@ -3,4 +3,4 @@ require conf/distro/poky.conf
 # Systemd is not yet in poky
 # rpi-zram-service is a systemd service
 # and it needs systemd
-BBMASK = "rpi-zram-service"
+BBMASK ?= "rpi-zram-service"