From patchwork Fri Nov 7 09:02:47 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Lothar_Wa=C3=9Fmann?= X-Patchwork-Id: 408007 Return-Path: X-Original-To: incoming-imx@patchwork.ozlabs.org Delivered-To: patchwork-incoming-imx@bilbo.ozlabs.org Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2001:1868:205::9]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id E739E14008C for ; Fri, 7 Nov 2014 20:08:09 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XmfUT-0003FK-UG; Fri, 07 Nov 2014 09:05:57 +0000 Received: from mail.karo-electronics.de ([81.173.242.67]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XmfUQ-00038J-3x for linux-arm-kernel@lists.infradead.org; Fri, 07 Nov 2014 09:05:54 +0000 From: =?UTF-8?q?Lothar=20Wa=C3=9Fmann?= To: netdev@vger.kernel.org Subject: [PATCHv4 1/1] net: fec: fix regression on i.MX28 introduced by rx_copybreak support Date: Fri, 7 Nov 2014 10:02:47 +0100 Message-Id: <1415350967-2238-2-git-send-email-LW@KARO-electronics.de> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1415350967-2238-1-git-send-email-LW@KARO-electronics.de> References: <1415350967-2238-1-git-send-email-LW@KARO-electronics.de> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20141107_010554_526368_ECE661DC X-CRM114-Status: GOOD ( 14.23 ) X-Spam-Score: -1.3 (-) X-Spam-Report: SpamAssassin version 3.4.0 on bombadil.infradead.org summary: Content analysis details: (-1.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [81.173.242.67 listed in list.dnswl.org] -0.6 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain Cc: Fabio Estevam , Frank Li , linux-kernel@vger.kernel.org, Russell King , "David S. Miller" , linux-arm-kernel@lists.infradead.org, =?UTF-8?q?Lothar=20Wa=C3=9Fmann?= X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+incoming-imx=patchwork.ozlabs.org@lists.infradead.org List-Id: linux-imx-kernel.lists.patchwork.ozlabs.org commit 1b7bde6d659d ("net: fec: implement rx_copybreak to improve rx performance") introduced a regression for i.MX28. The swap_buffer() function doing the endian conversion of the received data on i.MX28 may access memory beyond the actual packet size in the DMA buffer. fec_enet_copybreak() does not copy those bytes, so that the last bytes of a packet may be filled with invalid data after swapping. This will likely lead to checksum errors on received packets. E.g. when trying to mount an NFS rootfs: UDP: bad checksum. From 192.168.1.225:111 to 192.168.100.73:44662 ulen 36 Do the byte swapping and copying to the new skb in one go if necessary. Signed-off-by: Lothar Waßmann Tested-by: Fabio Estevam --- drivers/net/ethernet/freescale/fec_main.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index c27128d..3dca494 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -298,6 +298,16 @@ static void *swap_buffer(void *bufaddr, int len) return bufaddr; } +static void swap_buffer2(void *dst_buf, void *src_buf, int len) +{ + int i; + unsigned int *src = src_buf; + unsigned int *dst = dst_buf; + + for (i = 0; i < len; i += 4, src++, dst++) + *dst = swab32p(src); +} + static void fec_dump(struct net_device *ndev) { struct fec_enet_private *fep = netdev_priv(ndev); @@ -1307,7 +1317,7 @@ fec_enet_new_rxbdp(struct net_device *ndev, struct bufdesc *bdp, struct sk_buff } static bool fec_enet_copybreak(struct net_device *ndev, struct sk_buff **skb, - struct bufdesc *bdp, u32 length) + struct bufdesc *bdp, u32 length, bool swap) { struct fec_enet_private *fep = netdev_priv(ndev); struct sk_buff *new_skb; @@ -1322,7 +1332,10 @@ static bool fec_enet_copybreak(struct net_device *ndev, struct sk_buff **skb, dma_sync_single_for_cpu(&fep->pdev->dev, bdp->cbd_bufaddr, FEC_ENET_RX_FRSIZE - fep->rx_align, DMA_FROM_DEVICE); - memcpy(new_skb->data, (*skb)->data, length); + if (!swap) + memcpy(new_skb->data, (*skb)->data, length); + else + swap_buffer2(new_skb->data, (*skb)->data, length); *skb = new_skb; return true; @@ -1352,6 +1365,7 @@ fec_enet_rx_queue(struct net_device *ndev, int budget, u16 queue_id) u16 vlan_tag; int index = 0; bool is_copybreak; + bool need_swap = id_entry->driver_data & FEC_QUIRK_SWAP_FRAME; #ifdef CONFIG_M532x flush_cache_all(); @@ -1415,7 +1429,8 @@ fec_enet_rx_queue(struct net_device *ndev, int budget, u16 queue_id) * include that when passing upstream as it messes up * bridging applications. */ - is_copybreak = fec_enet_copybreak(ndev, &skb, bdp, pkt_len - 4); + is_copybreak = fec_enet_copybreak(ndev, &skb, bdp, pkt_len - 4, + need_swap); if (!is_copybreak) { skb_new = netdev_alloc_skb(ndev, FEC_ENET_RX_FRSIZE); if (unlikely(!skb_new)) { @@ -1430,7 +1445,7 @@ fec_enet_rx_queue(struct net_device *ndev, int budget, u16 queue_id) prefetch(skb->data - NET_IP_ALIGN); skb_put(skb, pkt_len - 4); data = skb->data; - if (id_entry->driver_data & FEC_QUIRK_SWAP_FRAME) + if (!is_copybreak && need_swap) swap_buffer(data, pkt_len); /* Extract the enhanced buffer descriptor */