Fix bug in the netfront driver that caused excessive packet drops during

receive processing.

Remove unnecessary restrictions on the mbuf chain length built during an
LRO receive.  This restriction was copied from the Linux netfront driver
where the LRO implementation cannot handle more than 18 discontinuities.
The FreeBSD implementation has no such restriction.

MFC after: 1 week

1 files changed, 1 insertions, 12 deletions

diff --git a/sys/dev/xen/netfront/netfront.c b/sys/dev/xen/netfront/netfront.c
index 61b14af..e47c3cc 100644
--- a/sys/dev/xen/netfront/netfront.c
+++ b/sys/dev/xen/netfront/netfront.c
@@ -1273,7 +1273,6 @@ xennet_get_responses(struct netfront_info *np,
 	struct mbuf *m, *m0, *m_prev;
 	grant_ref_t ref = xennet_get_rx_ref(np, *cons);
 	RING_IDX ref_cons = *cons;
-	int max = 5 /* MAX_TX_REQ_FRAGS + (rx->status <= RX_COPY_THRESHOLD) */;
 	int frags = 1;
 	int err = 0;
 	u_long ret;
@@ -1416,20 +1415,10 @@ next_skip_queue:
 		frags++;
 	}
 	*list = m0;
-
-	if (unlikely(frags > max)) {
-		if (net_ratelimit())
-			WPRINTK("Too many frags\n");
-		printf("%s: too many frags %d > max %d\n", __func__, frags,
-		       max);
-		err = E2BIG;
-	}
-
 	*cons += frags;
-
 	*pages_flipped_p = pages_flipped;
 
-	return err;
+	return (err);
 }
 
 static void