| Message ID | 1381145893-20930-3-git-send-email-amirv@mellanox.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On Mon, 2013-10-07 at 13:38 +0200, Amir Vadai wrote: > This patch fixes a bug introduced by commit 51151a16 (mlx4: allow > order-0 memory allocations in RX path). > > dma_unmap_page never reached because condition to detect last fragment > in page is wrong. offset+frag_stride can't be greater than size, need to > make sure no additional frag will fit in page => compare offset + > frag_stride + next_frag_size instead. > next_frag_size is the same as the current one, since page is shared only > with frags of the same size. > > CC: Eric Dumazet <edumazet@google.com> > Signed-off-by: Amir Vadai <amirv@mellanox.com> > --- > After looking at the code again, need to use 2*frag_stride and not to look at > size of next frag in skb. Changed it accordingly Yes indeed this looks much better, thanks ! Acked-by: Eric Dumazet <edumazet@google.com> -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c index 066fc27..afe2efa 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c @@ -135,9 +135,10 @@ static void mlx4_en_free_frag(struct mlx4_en_priv *priv, int i) { const struct mlx4_en_frag_info *frag_info = &priv->frag_info[i]; + u32 next_frag_end = frags[i].page_offset + 2 * frag_info->frag_stride; - if (frags[i].page_offset + frag_info->frag_stride > - frags[i].page_size) + + if (next_frag_end > frags[i].page_size) dma_unmap_page(priv->ddev, frags[i].dma, frags[i].page_size, PCI_DMA_FROMDEVICE);
This patch fixes a bug introduced by commit 51151a16 (mlx4: allow order-0 memory allocations in RX path). dma_unmap_page never reached because condition to detect last fragment in page is wrong. offset+frag_stride can't be greater than size, need to make sure no additional frag will fit in page => compare offset + frag_stride + next_frag_size instead. next_frag_size is the same as the current one, since page is shared only with frags of the same size. CC: Eric Dumazet <edumazet@google.com> Signed-off-by: Amir Vadai <amirv@mellanox.com> --- After looking at the code again, need to use 2*frag_stride and not to look at size of next frag in skb. Changed it accordingly drivers/net/ethernet/mellanox/mlx4/en_rx.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)