diff --git a/toolchain/kernel-headers/Makefile b/toolchain/kernel-headers/Makefile
index 3731673e5d..f95c8b95a9 100644
--- a/toolchain/kernel-headers/Makefile
+++ b/toolchain/kernel-headers/Makefile
@@ -33,6 +33,7 @@ endef
 
 ifneq (,$(findstring uml,$(BOARD)))
   KMAKE := $(MAKE) -C $(PKG_BUILD_DIR) \
+		ARCH=i386 \
 		CONFIG_SHELL=$(BASH)
 else
   KMAKE := $(MAKE) -C $(PKG_BUILD_DIR) \