diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index bc4e9d84157f..e0e6990723e9 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -385,7 +385,7 @@ void free_initmem(void)
 }
 
 #ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
+void __init free_initrd_mem(unsigned long start, unsigned long end)
 {
 	/*
 	 * end could be not aligned, and We can not align that,