[PATCHv3 9/9] net: fec: fix regression on i.MX28 introduced by rx_copybreak support
From: Lothar Waßmann <hidden>
Date: 2014-10-28 13:23:16
Also in:
linux-arm-kernel, lkml
Subsystem:
freescale imx / mxc fec driver, networking drivers, the rest · Maintainers:
Wei Fang, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
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 <redacted>
---
drivers/net/ethernet/freescale/fec_main.c | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index e52864c..5ee4912 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c@@ -294,7 +294,16 @@ static void swap_buffer(void *bufaddr, int len) for (i = 0; i < len; i += 4, buf++) swab32s(buf); +} + +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)
@@ -1292,7 +1301,7 @@ 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;
@@ -1307,7 +1316,10 @@ 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;
@@ -1335,6 +1347,7 @@ 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 = fep->quirks & FEC_QUIRK_SWAP_FRAME; #ifdef CONFIG_M532x flush_cache_all();
@@ -1398,7 +1411,8 @@ 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)) {
@@ -1413,7 +1427,7 @@ 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 (fep->quirks & FEC_QUIRK_SWAP_FRAME) + if (!is_copybreak && need_swap) swap_buffer(data, pkt_len); /* Extract the enhanced buffer descriptor */
--
1.7.10.4
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel