diff --git a/Makefile b/Makefile
index f8e325709bf3..dee707c98bbe 100644
--- a/Makefile
+++ b/Makefile
@@ -129,6 +129,9 @@ endif
 $(if $(word 2, $(KBUILD_EXTMOD)), \
 	$(error building multiple external modules is not supported))
 
+$(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
+	$(error module directory path cannot contain '$x')))
+
 # Remove trailing slashes
 ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
 KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)