This is a note to let you know that I've just added the patch titled bnx2x: fix DMA unmapping of TSO split BDs to the 3.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: bnx2x-fix-dma-unmapping-of-tso-split-bds.patch and it can be found in the queue-3.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Tue Feb 4 09:07:36 PST 2014 From: Michal Schmidt <mschmidt@xxxxxxxxxx> Date: Thu, 9 Jan 2014 14:36:27 +0100 Subject: bnx2x: fix DMA unmapping of TSO split BDs From: Michal Schmidt <mschmidt@xxxxxxxxxx> [ Upstream commit 95e92fd40c967c363ad66b2fd1ce4dcd68132e54 ] bnx2x triggers warnings with CONFIG_DMA_API_DEBUG=y: WARNING: CPU: 0 PID: 2253 at lib/dma-debug.c:887 check_unmap+0xf8/0x920() bnx2x 0000:28:00.0: DMA-API: device driver frees DMA memory with different size [device address=0x00000000da2b389e] [map size=1490 bytes] [unmap size=66 bytes] The reason is that bnx2x splits a TSO BD into two BDs (headers + data) using one DMA mapping for both, but it uses only the length of the first BD when unmapping. This patch fixes the bug by unmapping the whole length of the two BDs. Signed-off-by: Michal Schmidt <mschmidt@xxxxxxxxxx> Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx> Acked-by: Dmitry Kravkov <dmitry@xxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) --- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c +++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c @@ -153,6 +153,7 @@ static u16 bnx2x_free_tx_pkt(struct bnx2 struct sk_buff *skb = tx_buf->skb; u16 bd_idx = TX_BD(tx_buf->first_bd), new_cons; int nbd; + u16 split_bd_len = 0; /* prefetch skb end pointer to speedup dev_kfree_skb() */ prefetch(&skb->end); @@ -160,10 +161,7 @@ static u16 bnx2x_free_tx_pkt(struct bnx2 DP(NETIF_MSG_TX_DONE, "fp[%d]: pkt_idx %d buff @(%p)->skb %p\n", txdata->txq_index, idx, tx_buf, skb); - /* unmap first bd */ tx_start_bd = &txdata->tx_desc_ring[bd_idx].start_bd; - dma_unmap_single(&bp->pdev->dev, BD_UNMAP_ADDR(tx_start_bd), - BD_UNMAP_LEN(tx_start_bd), DMA_TO_DEVICE); nbd = le16_to_cpu(tx_start_bd->nbd) - 1; @@ -182,12 +180,19 @@ static u16 bnx2x_free_tx_pkt(struct bnx2 --nbd; bd_idx = TX_BD(NEXT_TX_IDX(bd_idx)); - /* ...and the TSO split header bd since they have no mapping */ + /* TSO headers+data bds share a common mapping. See bnx2x_tx_split() */ if (tx_buf->flags & BNX2X_TSO_SPLIT_BD) { + tx_data_bd = &txdata->tx_desc_ring[bd_idx].reg_bd; + split_bd_len = BD_UNMAP_LEN(tx_data_bd); --nbd; bd_idx = TX_BD(NEXT_TX_IDX(bd_idx)); } + /* unmap first bd */ + dma_unmap_single(&bp->pdev->dev, BD_UNMAP_ADDR(tx_start_bd), + BD_UNMAP_LEN(tx_start_bd) + split_bd_len, + DMA_TO_DEVICE); + /* now free frags */ while (nbd > 0) { Patches currently in stable-queue which might be from mschmidt@xxxxxxxxxx are queue-3.10/bnx2x-fix-dma-unmapping-of-tso-split-bds.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html