---

yaml
---
r: 27317
b: refs/heads/master
c: 96f9c2e
h: refs/heads/master
i:
  27315: d6e002e
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 4e3ceac609cce39cb96e0eb8604934592371ed8c
+refs/heads/master: 96f9c2e277768099479fbed7c3b69c294b1fadef

trunk/drivers/net/ixgb/ixgb_main.c

@@ -1266,6 +1266,7 @@ ixgb_tx_map(struct ixgb_adapter *adapter, struct sk_buff *skb,
 	struct ixgb_buffer *buffer_info;
 	int len = skb->len;
 	unsigned int offset = 0, size, count = 0, i;
+	unsigned int mss = skb_shinfo(skb)->tso_size;
 
 	unsigned int nr_frags = skb_shinfo(skb)->nr_frags;
 	unsigned int f;
@@ -1277,6 +1278,11 @@ ixgb_tx_map(struct ixgb_adapter *adapter, struct sk_buff *skb,
 	while(len) {
 		buffer_info = &tx_ring->buffer_info[i];
 		size = min(len, IXGB_MAX_JUMBO_FRAME_SIZE);
+		/* Workaround for premature desc write-backs
+		 * in TSO mode.  Append 4-byte sentinel desc */
+		if(unlikely(mss && !nr_frags && size == len && size > 8))
+			size -= 4;
+
 		buffer_info->length = size;
 		buffer_info->dma =
 			pci_map_single(adapter->pdev,
@@ -1301,6 +1307,12 @@ ixgb_tx_map(struct ixgb_adapter *adapter, struct sk_buff *skb,
 		while(len) {
 			buffer_info = &tx_ring->buffer_info[i];
 			size = min(len, IXGB_MAX_JUMBO_FRAME_SIZE);
+			/* Workaround for premature desc write-backs
+			 * in TSO mode.  Append 4-byte sentinel desc */
+			if(unlikely(mss && (f == (nr_frags-1)) && (size == len)
+			            && (size > 8)))
+				size -= 4;
+
 			buffer_info->length = size;
 			buffer_info->dma =
 				pci_map_page(adapter->pdev,
@@ -1378,7 +1390,8 @@ ixgb_tx_queue(struct ixgb_adapter *adapter, int count, int vlan_id,int tx_flags)
 #define TXD_USE_COUNT(S) (((S) >> IXGB_MAX_TXD_PWR) + \
 			 (((S) & (IXGB_MAX_DATA_PER_TXD - 1)) ? 1 : 0))
 #define DESC_NEEDED TXD_USE_COUNT(IXGB_MAX_DATA_PER_TXD) + \
-	MAX_SKB_FRAGS * TXD_USE_COUNT(PAGE_SIZE) + 1
+	MAX_SKB_FRAGS * TXD_USE_COUNT(PAGE_SIZE) + 1 \
+	/* one more for TSO workaround */ + 1
 
 static int
 ixgb_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
@@ -1416,7 +1429,7 @@ ixgb_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
 		return NETDEV_TX_OK;
 	}
 
-	if (tso)
+	if (likely(tso))
 		tx_flags |= IXGB_TX_FLAGS_TSO;
 	else if(ixgb_tx_csum(adapter, skb))
 		tx_flags |= IXGB_TX_FLAGS_CSUM;