diff --git a/[refs] b/[refs]
index 7530b3000e86..ebc648715918 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 3b66a1edb01b82269a668a478625765b1fa4936f
+refs/heads/master: 2ab23c95a0b77d45dc764dd4aed48fe6e8906e59
diff --git a/trunk/Makefile b/trunk/Makefile
index 8560b79268ba..c31914400953 100644
--- a/trunk/Makefile
+++ b/trunk/Makefile
@@ -1193,6 +1193,17 @@ else
 __srctree = $(srctree)/
 endif
 
+ifeq ($(ALLSOURCE_ARCHS),)
+ifeq ($(ARCH),um)
+ALLINCLUDE_ARCHS := $(ARCH) $(SUBARCH)
+else
+ALLINCLUDE_ARCHS := $(ARCH)
+endif
+else
+#Allow user to specify only ALLSOURCE_PATHS on the command line, keeping existing behaviour.
+ALLINCLUDE_ARCHS := $(ALLSOURCE_ARCHS)
+endif
+
 ALLSOURCE_ARCHS := $(ARCH)
 
 define all-sources
@@ -1208,7 +1219,7 @@ define all-sources
 	  find $(__srctree)include $(RCS_FIND_IGNORE) \
 	       \( -name config -o -name 'asm-*' \) -prune \
 	       -o -name '*.[chS]' -print; \
-	  for ARCH in $(ALLSOURCE_ARCHS) ; do \
+	  for ARCH in $(ALLINCLUDE_ARCHS) ; do \
 	       find $(__srctree)include/asm-$${ARCH} $(RCS_FIND_IGNORE) \
 	            -name '*.[chS]' -print; \
 	  done ; \