From 773235f4e1cc41ea98f520a0cfe0a51a58b2d411 Mon Sep 17 00:00:00 2001 From: Heiner Kallweit Date: Sat, 18 Apr 2020 23:11:32 +0200 Subject: [PATCH] r8169: add workaround for RTL8168evl TSO hw issues Add workaround for hw issues with TSO on RTL8168evl. This workaround is based on information I got from Realtek, and *should* allow to safely enable TSO on this chip version. Signed-off-by: Heiner Kallweit Signed-off-by: David S. Miller --- drivers/net/ethernet/realtek/r8169_main.c | 34 +++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c index 2cd2b03..a8696d9 100644 --- a/drivers/net/ethernet/realtek/r8169_main.c +++ b/drivers/net/ethernet/realtek/r8169_main.c @@ -4306,6 +4306,37 @@ err_stop_0: return NETDEV_TX_BUSY; } +static unsigned int rtl_last_frag_len(struct sk_buff *skb) +{ + struct skb_shared_info *info = skb_shinfo(skb); + unsigned int nr_frags = info->nr_frags; + + if (!nr_frags) + return UINT_MAX; + + return skb_frag_size(info->frags + nr_frags - 1); +} + +/* Workaround for hw issues with TSO on RTL8168evl */ +static netdev_features_t rtl8168evl_fix_tso(struct sk_buff *skb, + netdev_features_t features) +{ + /* IPv4 header has options field */ + if (vlan_get_protocol(skb) == htons(ETH_P_IP) && + ip_hdrlen(skb) > sizeof(struct iphdr)) + features &= ~NETIF_F_ALL_TSO; + + /* IPv4 TCP header has options field */ + else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4 && + tcp_hdrlen(skb) > sizeof(struct tcphdr)) + features &= ~NETIF_F_ALL_TSO; + + else if (rtl_last_frag_len(skb) <= 6) + features &= ~NETIF_F_ALL_TSO; + + return features; +} + static netdev_features_t rtl8169_features_check(struct sk_buff *skb, struct net_device *dev, netdev_features_t features) @@ -4314,6 +4345,9 @@ static netdev_features_t rtl8169_features_check(struct sk_buff *skb, struct rtl8169_private *tp = netdev_priv(dev); if (skb_is_gso(skb)) { + if (tp->mac_version == RTL_GIGA_MAC_VER_34) + features = rtl8168evl_fix_tso(skb, features); + if (transport_offset > GTTCPHO_MAX && rtl_chip_supports_csum_v2(tp)) features &= ~NETIF_F_ALL_TSO; -- 2.7.4