Index: uipc_mbuf.c
===================================================================
RCS file: /cvs/src/sys/kern/uipc_mbuf.c,v
retrieving revision 1.198
diff -u -p -r1.198 uipc_mbuf.c
--- uipc_mbuf.c	5 Nov 2014 00:28:15 -0000	1.198
+++ uipc_mbuf.c	1 Dec 2014 00:43:07 -0000
@@ -160,7 +160,6 @@ mbinit(void)
 		    mclnames[i], NULL);
 		pool_setipl(&mclpools[i], IPL_NET);
 		pool_set_constraints(&mclpools[i], &kp_dma_contig);
-		pool_setlowat(&mclpools[i], mcllowat);
 	}
 
 	nmbclust_update();
@@ -185,7 +184,7 @@ nmbclust_update(void)
 		 * allocations in interrupt context don't fail or mclgeti()
 		 * drivers may end up with empty rings.
 		 */
-		pool_sethiwat(&mclpools[i], nmbclust);
+		// pool_sethiwat(&mclpools[i], nmbclust);
 	}
 	pool_sethiwat(&mbpool, nmbclust);
 }
@@ -1356,14 +1355,24 @@ mq_dequeue(struct mbuf_queue *mq)
 int
 mq_enlist(struct mbuf_queue *mq, struct mbuf_list *ml)
 {
-	int full;
+	struct mbuf *m;
+	int dropped = 0;
 
 	mtx_enter(&mq->mq_mtx);
-	ml_join(&mq->mq_list, ml);
-	full = mq_len(mq) >= mq->mq_maxlen;
+	if (mq_len(mq) < mq->mq_maxlen)
+		ml_join(&mq->mq_list, ml);
+	else {
+		mq->mq_drops += ml_len(ml);
+		dropped = 1;
+	}
 	mtx_leave(&mq->mq_mtx);
 
-	return (full);
+	if (dropped) {
+		while ((m = ml_dequeue(ml)) != NULL)
+			m_freem(m);
+	}
+
+	return (dropped);
 }
 
 void