From: Ben Hutchings <ben.hutchings@codethink.co.uk>
Date: Tue, 27 Jan 2015 00:49:47 +0000 (+0000)
Subject: sh_eth: Check for DMA mapping errors on transmit
X-Git-Tag: v3.19-rc7~23^2~5^2~1
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=aa3933b87309c61b4fa4bb93c1ad4c3f08afb1b8;p=users%2Fjedix%2Flinux-maple.git

sh_eth: Check for DMA mapping errors on transmit

dma_map_single() may fail if an IOMMU or swiotlb is in use, so
we need to check for this.

Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c
index 245166bbccfd..4a085da57188 100644
--- a/drivers/net/ethernet/renesas/sh_eth.c
+++ b/drivers/net/ethernet/renesas/sh_eth.c
@@ -2174,6 +2174,10 @@ static int sh_eth_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 				 skb->len + 2);
 	txdesc->addr = dma_map_single(&ndev->dev, skb->data, skb->len,
 				      DMA_TO_DEVICE);
+	if (dma_mapping_error(&ndev->dev, txdesc->addr)) {
+		kfree_skb(skb);
+		return NETDEV_TX_OK;
+	}
 	txdesc->buffer_length = skb->len;
 
 	if (entry >= mdp->num_tx_ring - 1)