From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: [PATCH] net: dont use __netdev_alloc_skb for bounce buffer Date: Mon, 02 Jul 2012 20:36:12 +0200 Message-ID: <1341254172.22621.456.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev , Stefan Bader To: David Miller Return-path: Received: from mail-ey0-f174.google.com ([209.85.215.174]:44530 "EHLO mail-ey0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755752Ab2GBSgQ (ORCPT ); Mon, 2 Jul 2012 14:36:16 -0400 Received: by eaak11 with SMTP id k11so2214056eaa.19 for ; Mon, 02 Jul 2012 11:36:15 -0700 (PDT) Sender: netdev-owner@vger.kernel.org List-ID: From: Eric Dumazet commit a1c7fff7e1 (net: netdev_alloc_skb() use build_skb()) broke b44 on some 64bit machines. It appears b44 and b43 use __netdev_alloc_skb() instead of alloc_skb() for their bounce buffers. There is no need to add an extra NET_SKB_PAD reservation for bounce buffers : - In TX path, NET_SKB_PAD is useless - In RX path in b44, we force a copy of incoming frames if GFP_DMA allocations were needed. Reported-and-bisected-by: Stefan Bader Signed-off-by: Eric Dumazet --- drivers/net/ethernet/broadcom/b44.c | 4 ++-- drivers/net/wireless/b43legacy/dma.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/broadcom/b44.c b/drivers/net/ethernet/broadcom/b44.c index 46b8b7d..d09c6b5 100644 --- a/drivers/net/ethernet/broadcom/b44.c +++ b/drivers/net/ethernet/broadcom/b44.c @@ -656,7 +656,7 @@ static int b44_alloc_rx_skb(struct b44 *bp, int src_idx, u32 dest_idx_unmasked) dma_unmap_single(bp->sdev->dma_dev, mapping, RX_PKT_BUF_SZ, DMA_FROM_DEVICE); dev_kfree_skb_any(skb); - skb = __netdev_alloc_skb(bp->dev, RX_PKT_BUF_SZ, GFP_ATOMIC|GFP_DMA); + skb = alloc_skb(RX_PKT_BUF_SZ, GFP_ATOMIC | GFP_DMA); if (skb == NULL) return -ENOMEM; mapping = dma_map_single(bp->sdev->dma_dev, skb->data, @@ -967,7 +967,7 @@ static netdev_tx_t b44_start_xmit(struct sk_buff *skb, struct net_device *dev) dma_unmap_single(bp->sdev->dma_dev, mapping, len, DMA_TO_DEVICE); - bounce_skb = __netdev_alloc_skb(dev, len, GFP_ATOMIC | GFP_DMA); + bounce_skb = alloc_skb(len, GFP_ATOMIC | GFP_DMA); if (!bounce_skb) goto err_out; diff --git a/drivers/net/wireless/b43legacy/dma.c b/drivers/net/wireless/b43legacy/dma.c index f1f8bd0..c8baf02 100644 --- a/drivers/net/wireless/b43legacy/dma.c +++ b/drivers/net/wireless/b43legacy/dma.c @@ -1072,7 +1072,7 @@ static int dma_tx_fragment(struct b43legacy_dmaring *ring, meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1); /* create a bounce buffer in zone_dma on mapping failure. */ if (b43legacy_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) { - bounce_skb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA); + bounce_skb = alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA); if (!bounce_skb) { ring->current_slot = old_top_slot; ring->used_slots = old_used_slots;