diff --git a/net/core/dev.c b/net/core/dev.c
index 4420086f3aeb3..53bef2aae3782 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3719,8 +3719,12 @@ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
 	 * separate lock before trying to get qdisc main lock.
 	 * This permits qdisc->running owner to get the lock more
 	 * often and dequeue packets faster.
+	 * On PREEMPT_RT it is possible to preempt the qdisc owner during xmit
+	 * and then other tasks will only enqueue packets. The packets will be
+	 * sent after the qdisc owner is scheduled again. To prevent this
+	 * scenario the task always serialize on the lock.
 	 */
-	contended = qdisc_is_running(q);
+	contended = IS_ENABLED(CONFIG_PREEMPT_RT) || qdisc_is_running(q);
 	if (unlikely(contended))
 		spin_lock(&q->busylock);