Index: boot/Makefile
===================================================================
--- boot/Makefile	(revision 41f7564e975bcef427a9a5bcbb0c12c9001f1a58)
+++ boot/Makefile	(revision 79f119b9e03afca087e6fef2c56a7fabb01c8cc1)
@@ -48,4 +48,8 @@
 endif
 
+ifeq ($(CONFIG_SMP),y)
+	DEFS += -DCONFIG_SMP
+endif
+
 .PHONY: all build config distclean clean generic_clean