diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 38e5939..d0f91d7 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -236,6 +236,7 @@
 	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
 		ieee80211_stop_queues_by_reason(&local->hw,
 						IEEE80211_QUEUE_STOP_REASON_PS);
+		ifmgd->flags &= ~IEEE80211_STA_NULLFUNC_ACKED;
 		ieee80211_queue_work(&local->hw,
 				     &local->dynamic_ps_disable_work);
 	}