diff --git a/poky/meta/classes/linux-dummy.bbclass b/poky/meta/classes/linux-dummy.bbclass
index cd87915..9a06a50 100644
--- a/poky/meta/classes/linux-dummy.bbclass
+++ b/poky/meta/classes/linux-dummy.bbclass
@@ -6,7 +6,7 @@
 
         # set an empty package of kernel-devicetree
         d.appendVar('PACKAGES', ' %s-devicetree' % kname)
-        d.setVar('ALLOW_EMPTY_%s-devicetree' % kname, '1')
+        d.setVar('ALLOW_EMPTY:%s-devicetree' % kname, '1')
 
         # Merge KERNEL_IMAGETYPE and KERNEL_ALT_IMAGETYPE into KERNEL_IMAGETYPES
         type = d.getVar('KERNEL_IMAGETYPE') or ""
@@ -21,6 +21,6 @@
         for type in types.split():
             typelower = type.lower()
             d.appendVar('PACKAGES', ' %s-image-%s' % (kname, typelower))
-            d.setVar('ALLOW_EMPTY_%s-image-%s' % (kname, typelower), '1')
+            d.setVar('ALLOW_EMPTY:%s-image-%s' % (kname, typelower), '1')
 }