watchdog: Don't change watchdog state on read of sysctl

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
[ add {}'s to fix a warning ]
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: <stable@kernel.org>
LKML-Reference: <1296230433-6261-3-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/watchdog.c

@@ -493,10 +493,12 @@ int proc_dowatchdog_enabled(struct ctl_table *table, int write,
 {
 	proc_dointvec(table, write, buffer, length, ppos);
 
-	if (watchdog_enabled)
-		watchdog_enable_all_cpus();
-	else
-		watchdog_disable_all_cpus();
+	if (write) {
+		if (watchdog_enabled)
+			watchdog_enable_all_cpus();
+		else
+			watchdog_disable_all_cpus();
+	}
 	return 0;
 }