diff --git a/bitbake/lib/bb/cooker.py b/bitbake/lib/bb/cooker.py
index fb38289397..a2b0bb5d7d 100644
--- a/bitbake/lib/bb/cooker.py
+++ b/bitbake/lib/bb/cooker.py
@@ -527,9 +527,11 @@ class BBCooker:
         self.handleCollections( self.data.getVar("BBFILE_COLLECTIONS", True) )
 
     def updateConfigOpts(self, options, environment):
-        for o in options:
-            setattr(self.configuration, o, options[o])
         clean = True
+        for o in options:
+            if o in ['prefile', 'postfile']:
+                clean = False
+            setattr(self.configuration, o, options[o])
         for k in bb.utils.approved_variables():
             if k in environment and k not in self.configuration.env:
                 logger.debug(1, "Updating environment variable %s to %s" % (k, environment[k]))
diff --git a/bitbake/lib/bb/cookerdata.py b/bitbake/lib/bb/cookerdata.py
index 57fc6bb50e..b20040c0b3 100644
--- a/bitbake/lib/bb/cookerdata.py
+++ b/bitbake/lib/bb/cookerdata.py
@@ -73,7 +73,8 @@ class ConfigParameters(object):
         options = {}
         for o in ["abort", "tryaltconfigs", "force", "invalidate_stamp", 
                   "verbose", "debug", "dry_run", "dump_signatures", 
-                  "debug_domains", "extra_assume_provided", "profile"]:
+                  "debug_domains", "extra_assume_provided", "profile",
+                  "prefile", "postfile"]:
             options[o] = getattr(self.options, o)
 
         ret, error = server.runCommand(["updateConfig", options, environment])