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>

1 files changed, 4 insertions, 0 deletions

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)