diff --git a/Makefile b/Makefile
index 131950c..c380f58 100644
--- a/Makefile
+++ b/Makefile
@@ -1284,7 +1284,7 @@
 #  build-dir  => directory in kernel source tree to use
 
 ifeq ($(KBUILD_EXTMOD),)
-        build-dir  = $(dir $@)
+        build-dir  = $(patsubst %/,%,$(dir $@))
         target-dir = $(dir $@)
 else
         zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))