diff --git a/[refs] b/[refs]
index 3929ab0aad4d..688fb400c010 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ac031f26e89cc04fc7504f31ae137857eb83a051
+refs/heads/master: 3041e47e8b08d51188b2cbdbd9c1e6f43314c8f1
diff --git a/trunk/Makefile b/trunk/Makefile
index d810d6cb4d08..1888fabe4032 100644
--- a/trunk/Makefile
+++ b/trunk/Makefile
@@ -446,7 +446,11 @@ $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
 # if auto.conf.cmd is missing then we are probarly in a cleaned tree so
 # we execute the config step to be sure to catch updated Kconfig files
 include/config/auto.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
+ifeq ($(KBUILD_EXTMOD),)
 	$(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
+else
+	$(error kernel configuration not valid - run 'make prepare' in $(srctree) to update it)
+endif
 
 else
 # Dummy target needed, because used as prerequisite