diff --git a/sys/dev/drm/linux_hrtimer.c b/sys/dev/drm/linux_hrtimer.c
--- a/sys/dev/drm/linux_hrtimer.c
+++ b/sys/dev/drm/linux_hrtimer.c
@@ -108,6 +108,9 @@
 
 	lwkt_gettoken(&timer->timer_token);
 
+	if (timer->active)
+		systimer_del(&timer->st);
+
 	timer->cancel = false;
 	timer->running = false;
 	timer->active = true;