diff --git a/[refs] b/[refs]
index 5b6b885dc546..aa60fd782528 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 4841158b26e28e1476eed84c7347c18f11317750
+refs/heads/master: 79ef2bb01445400def20c7993b27fbcad27ca95f
diff --git a/trunk/kernel/time/clocksource.c b/trunk/kernel/time/clocksource.c
index 592bf584d1d2..7466cb811251 100644
--- a/trunk/kernel/time/clocksource.c
+++ b/trunk/kernel/time/clocksource.c
@@ -513,7 +513,7 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev,
 	 * Check to make sure we don't switch to a non-highres capable
 	 * clocksource if the tick code is in oneshot mode (highres or nohz)
 	 */
-	if (tick_oneshot_mode_active() &&
+	if (tick_oneshot_mode_active() && ovr &&
 	    !(ovr->flags & CLOCK_SOURCE_VALID_FOR_HRES)) {
 		printk(KERN_WARNING "%s clocksource is not HRT compatible. "
 			"Cannot switch while in HRT/NOHZ mode\n", ovr->name);