| Message ID | 1415350967-2238-2-git-send-email-LW@KARO-electronics.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Nov 7, 2014 at 7:02 AM, Lothar Waßmann <LW@karo-electronics.de> wrote: > 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 <LW@KARO-electronics.de> With this patch I am able to NFS mount on mx28 again. Thanks, Lothar! Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
From: Fabio Estevam <festevam@gmail.com> Date: Fri, 7 Nov 2014 10:26:15 -0200 > On Fri, Nov 7, 2014 at 7:02 AM, Lothar Waßmann <LW@karo-electronics.de> wrote: >> 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 <LW@KARO-electronics.de> > > With this patch I am able to NFS mount on mx28 again. Thanks, Lothar! > > Tested-by: Fabio Estevam <fabio.estevam@freescale.com> Applied, thanks everyone.
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 */
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 <LW@KARO-electronics.de> --- drivers/net/ethernet/freescale/fec_main.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-)