From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: [PATCH v2] r8169: fix rx checksum offload Date: Sun, 05 Sep 2010 22:45:01 +0200 Message-ID: <1283719501.3402.393.camel@edumazet-laptop> References: <1283716996.3402.342.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev , Francois Romieu , Neil Horman To: David Miller Return-path: Received: from mail-fx0-f46.google.com ([209.85.161.46]:61428 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754502Ab0IEUpJ (ORCPT ); Sun, 5 Sep 2010 16:45:09 -0400 Received: by fxm13 with SMTP id 13so2200302fxm.19 for ; Sun, 05 Sep 2010 13:45:07 -0700 (PDT) In-Reply-To: <1283716996.3402.342.camel@edumazet-laptop> Sender: netdev-owner@vger.kernel.org List-ID: While porting GRO to r8169, I found this driver has a bug in its rx path. All skbs given to network stack had their ip_summed set to CHECKSUM_NONE, while hardware said they had correct TCP/UDP checksums. The reason is driver sets skb->ip_summed on the original skb before the copy eventually done by copybreak. The fresh skb gets the ip_summed = CHECKSUM_NONE value, forcing network stack to recompute checksum, and preventing my GRO patch to work. Fix is to make the ip_summed setting after skb copy. Note : rx_copybreak current value is 16383, so all frames are copied... Signed-off-by: Eric Dumazet --- v2: reuse 'status' variable drivers/net/r8169.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c index 3554041..792eccb 100644 --- a/drivers/net/r8169.c +++ b/drivers/net/r8169.c @@ -4458,9 +4458,8 @@ static inline int rtl8169_fragmented_frame(u32 status) return (status & (FirstFrag | LastFrag)) != (FirstFrag | LastFrag); } -static inline void rtl8169_rx_csum(struct sk_buff *skb, struct RxDesc *desc) +static inline void rtl8169_rx_csum(struct sk_buff *skb, u32 opts1) { - u32 opts1 = le32_to_cpu(desc->opts1); u32 status = opts1 & RxProtoMask; if (((status == RxProtoTCP) && !(opts1 & TCPFail)) || @@ -4554,8 +4553,6 @@ static int rtl8169_rx_interrupt(struct net_device *dev, continue; } - rtl8169_rx_csum(skb, desc); - if (rtl8169_try_rx_copy(&skb, tp, pkt_size, addr)) { pci_dma_sync_single_for_device(pdev, addr, pkt_size, PCI_DMA_FROMDEVICE); @@ -4566,6 +4563,7 @@ static int rtl8169_rx_interrupt(struct net_device *dev, tp->Rx_skbuff[entry] = NULL; } + rtl8169_rx_csum(skb, status); skb_put(skb, pkt_size); skb->protocol = eth_type_trans(skb, dev);