diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 2166ff17692c..25e49b4d8049 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -108,8 +108,6 @@
 
 #if defined(CONFIG_SYSCTL)
 
-/* External variables not in a header file. */
-
 /* Constants used for minimum and  maximum */
 #ifdef CONFIG_LOCKUP_DETECTOR
 static int sixty = 60;