diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index 406f6f9..19d1b29 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -60,6 +60,7 @@
 void kgdb_breakpoint(void);
 
 extern int kgdb_connected;
+extern int kgdb_io_module_registered;
 
 extern atomic_t			kgdb_setting_breakpoint;
 extern atomic_t			kgdb_cpu_doing_single_step;