diff --git a/Makefile b/Makefile
index 7294d4051ff2..04bee1c5b400 100644
--- a/Makefile
+++ b/Makefile
@@ -1091,7 +1091,9 @@ PHONY += prepare archprepare prepare1 prepare3
 prepare3: include/config/kernel.release
 ifneq ($(srctree),.)
 	@$(kecho) '  Using $(srctree) as source for kernel'
-	$(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
+	$(Q)if [ -f $(srctree)/.config -o \
+		 -d $(srctree)/include/config -o \
+		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
 		echo >&2 "  $(srctree) is not clean, please run 'make mrproper'"; \
 		echo >&2 "  in the '$(srctree)' directory.";\
 		/bin/false; \
@@ -1350,7 +1352,7 @@ CLEAN_DIRS  += $(MODVERDIR) include/ksym
 
 # Directories & files removed with 'make mrproper'
 MRPROPER_DIRS  += include/config usr/include include/generated          \
-		  arch/*/include/generated .tmp_objdiff
+		  arch/$(SRCARCH)/include/generated .tmp_objdiff
 MRPROPER_FILES += .config .config.old .version \
 		  Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS \
 		  signing_key.pem signing_key.priv signing_key.x509	\