fix theoretical race condition, although there is quite possibly still a race with the destruction of the waitq/compl
fix theoretical race condition, although there is quite possibly still a race with the destruction of the waitq/compl

pscedu/slash2-stable,pscedu/pfl,pscedu/slash2-stable,pscedu/slash2-stable,pscedu/slash2-stable,pscedu/pfl,pscedu/slash2-stable,pscedu/pfl,pscedu/slash2-stable,pscedu/pfl,pscedu/slash2-stable