diff --git a/arch/m32r/kernel/smpboot.c b/arch/m32r/kernel/smpboot.c
index fc2994811f150c991986b6294538ca5b9c6a64ab..39cb6da72dcbef3358d04e2b419a150f88c299ba 100644
--- a/arch/m32r/kernel/smpboot.c
+++ b/arch/m32r/kernel/smpboot.c
@@ -40,6 +40,7 @@
  */
 
 #include <linux/module.h>
+#include <linux/cpu.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>