---

yaml
---
r: 194287
b: refs/heads/master
c: fc6055a
h: refs/heads/master
i:
  194285: 72cc227
  194283: b3ce6dc
  194279: 399f210
  194271: 4fe50bb
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9958da0501fced47c1ac5c5a3a7731c87e45472c
+refs/heads/master: fc6055a5ba31e2c14e36e8939f9bf2b6d586a7f5

trunk/net/core/dev.c

@@ -1880,6 +1880,17 @@ static int dev_gso_segment(struct sk_buff *skb)
 	return 0;
 }
 
+/*
+ * Try to orphan skb early, right before transmission by the device.
+ * We cannot orphan skb if tx timestamp is requested, since
+ * drivers need to call skb_tstamp_tx() to send the timestamp.
+ */
+static inline void skb_orphan_try(struct sk_buff *skb)
+{
+	if (!skb_tx(skb)->flags)
+		skb_orphan(skb);
+}
+
 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
 			struct netdev_queue *txq)
 {
@@ -1904,23 +1915,10 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
 		if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
 			skb_dst_drop(skb);
 
+		skb_orphan_try(skb);
 		rc = ops->ndo_start_xmit(skb, dev);
 		if (rc == NETDEV_TX_OK)
 			txq_trans_update(txq);
-		/*
-		 * TODO: if skb_orphan() was called by
-		 * dev->hard_start_xmit() (for example, the unmodified
-		 * igb driver does that; bnx2 doesn't), then
-		 * skb_tx_software_timestamp() will be unable to send
-		 * back the time stamp.
-		 *
-		 * How can this be prevented? Always create another
-		 * reference to the socket before calling
-		 * dev->hard_start_xmit()? Prevent that skb_orphan()
-		 * does anything in dev->hard_start_xmit() by clearing
-		 * the skb destructor before the call and restoring it
-		 * afterwards, then doing the skb_orphan() ourselves?
-		 */
 		return rc;
 	}
 
@@ -1938,6 +1936,7 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
 		if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
 			skb_dst_drop(nskb);
 
+		skb_orphan_try(nskb);
 		rc = ops->ndo_start_xmit(nskb, dev);
 		if (unlikely(rc != NETDEV_TX_OK)) {
 			if (rc & ~NETDEV_TX_MASK)