diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 0c2b7ef..294f26d 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -14,6 +14,7 @@
 #include <linux/bootmem.h>
 #include <linux/pfn.h>
 #include <linux/suspend.h>
+#include <linux/acpi.h>
 #include <linux/firmware-map.h>
 #include <linux/memblock.h>