[PATCH 5.9 042/133] r8169: work around short packet hw bug on RTL8125

From: Greg Kroah-Hartman
Date: Mon Nov 09 2020 - 08:17:33 EST


From: Heiner Kallweit <hkallweit1@xxxxxxxxx>

[ Upstream commit 2aaf09a0e7842b3ac7be6e0b8fb1888b3daeb3b3 ]

Network problems with RTL8125B have been reported [0] and with help
from Realtek it turned out that this chip version has a hw problem
with short packets (similar to RTL8168evl). Having said that activate
the same workaround as for RTL8168evl.
Realtek suggested to activate the workaround for RTL8125A too, even
though they're not 100% sure yet which RTL8125 versions are affected.

[0] https://bugzilla.kernel.org/show_bug.cgi?id=209839

Fixes: 0439297be951 ("r8169: add support for RTL8125B")
Reported-by: Maxim Plotnikov <wgh@xxxxxxxxx>
Tested-by: Maxim Plotnikov <wgh@xxxxxxxxx>
Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
Link: https://lore.kernel.org/r/8002c31a-60b9-58f1-f0dd-8fd07239917f@xxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/realtek/r8169_main.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)

--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -4062,9 +4062,17 @@ err_out:
return -EIO;
}

-static bool rtl_test_hw_pad_bug(struct rtl8169_private *tp, struct sk_buff *skb)
+static bool rtl_test_hw_pad_bug(struct rtl8169_private *tp)
{
- return skb->len < ETH_ZLEN && tp->mac_version == RTL_GIGA_MAC_VER_34;
+ switch (tp->mac_version) {
+ case RTL_GIGA_MAC_VER_34:
+ case RTL_GIGA_MAC_VER_60:
+ case RTL_GIGA_MAC_VER_61:
+ case RTL_GIGA_MAC_VER_63:
+ return true;
+ default:
+ return false;
+ }
}

static void rtl8169_tso_csum_v1(struct sk_buff *skb, u32 *opts)
@@ -4136,7 +4144,7 @@ static bool rtl8169_tso_csum_v2(struct r

opts[1] |= transport_offset << TCPHO_SHIFT;
} else {
- if (unlikely(rtl_test_hw_pad_bug(tp, skb)))
+ if (unlikely(skb->len < ETH_ZLEN && rtl_test_hw_pad_bug(tp)))
return !eth_skb_pad(skb);
}