From 3361dc9538832a2a9150a8c722374ca844bf8dc8 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Fri, 20 Sep 2013 13:53:22 -0400 Subject: [PATCH] skge: fix invalid value passed to pci_unmap_sigle In my patch c194992cbe71c20bb3623a566af8d11b0bfaa721 ("skge: fix broken driver") I didn't fix the skge bug correctly. The value of the new mapping (not old) was passed to pci_unmap_single. If we enable CONFIG_DMA_API_DEBUG, it results in this warning: WARNING: CPU: 0 PID: 0 at lib/dma-debug.c:986 check_sync+0x4c4/0x580() skge 0000:02:07.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x000000023a0096c0] [size=1536 bytes] This patch makes the skge driver pass the correct value to pci_unmap_single and fixes the warning. It copies the old descriptor to on-stack variable "ee" and unmaps it if mapping of the new descriptor succeeded. This patch should be backported to 3.11-stable. Signed-off-by: Mikulas Patocka Reported-by: Francois Romieu Tested-by: Mikulas Patocka Signed-off-by: David S. Miller --- drivers/net/ethernet/marvell/skge.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/marvell/skge.c b/drivers/net/ethernet/marvell/skge.c index 1a9c4f6269ea..ecc7f7b696b8 100644 --- a/drivers/net/ethernet/marvell/skge.c +++ b/drivers/net/ethernet/marvell/skge.c @@ -3086,13 +3086,16 @@ static struct sk_buff *skge_rx_get(struct net_device *dev, PCI_DMA_FROMDEVICE); skge_rx_reuse(e, skge->rx_buf_size); } else { + struct skge_element ee; struct sk_buff *nskb; nskb = netdev_alloc_skb_ip_align(dev, skge->rx_buf_size); if (!nskb) goto resubmit; - skb = e->skb; + ee = *e; + + skb = ee.skb; prefetch(skb->data); if (skge_rx_setup(skge, e, nskb, skge->rx_buf_size) < 0) { @@ -3101,8 +3104,8 @@ static struct sk_buff *skge_rx_get(struct net_device *dev, } pci_unmap_single(skge->hw->pdev, - dma_unmap_addr(e, mapaddr), - dma_unmap_len(e, maplen), + dma_unmap_addr(&ee, mapaddr), + dma_unmap_len(&ee, maplen), PCI_DMA_FROMDEVICE); }