diff --git a/arch/um/Kconfig b/arch/um/Kconfig
index 9a23df1..c529218 100644
--- a/arch/um/Kconfig
+++ b/arch/um/Kconfig
@@ -244,6 +244,7 @@
 
 config HIGHMEM
 	bool "Highmem support"
+	depends on !64BIT
 
 config KERNEL_STACK_ORDER
 	int "Kernel stack size order"