releases/4.14.117/net-stmmac-don-t-overwrite-discard_frame-status.patch

   1 From 4cf6345dd90f3c3d69f6971768224453d1cf0e14 Mon Sep 17 00:00:00 2001
   2 From: Aaro Koskinen <aaro.koskinen@nokia.com>
   3 Date: Wed, 27 Mar 2019 22:35:38 +0200
   4 Subject: net: stmmac: don't overwrite discard_frame status
   5
   6 [ Upstream commit 1b746ce8b397e58f9e40ce5c63b7198de6930482 ]
   7
   8 If we have error bits set, the discard_frame status will get overwritten
   9 by checksum bit checks, which might set the status back to good one.
  10 Fix by checking the COE status only if the frame is good.
  11
  12 Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
  13 Signed-off-by: David S. Miller <davem@davemloft.net>
  14 Signed-off-by: Sasha Levin <sashal@kernel.org>
  15 ---
  16  drivers/net/ethernet/stmicro/stmmac/enh_desc.c | 7 ++++---
  17  1 file changed, 4 insertions(+), 3 deletions(-)
  18
  19 diff --git a/drivers/net/ethernet/stmicro/stmmac/enh_desc.c b/drivers/net/ethernet/stmicro/stmmac/enh_desc.c
  20 index acd65a4f94d4..cdfe9a350ac0 100644
  21 --- a/drivers/net/ethernet/stmicro/stmmac/enh_desc.c
  22 +++ b/drivers/net/ethernet/stmicro/stmmac/enh_desc.c
  23 @@ -231,9 +231,10 @@ static int enh_desc_get_rx_status(void *data, struct stmmac_extra_stats *x,
  24          * It doesn't match with the information reported into the databook.
  25          * At any rate, we need to understand if the CSUM hw computation is ok
  26          * and report this info to the upper layers. */
  27 -       ret = enh_desc_coe_rdes0(!!(rdes0 & RDES0_IPC_CSUM_ERROR),
  28 -                                !!(rdes0 & RDES0_FRAME_TYPE),
  29 -                                !!(rdes0 & ERDES0_RX_MAC_ADDR));
  30 +       if (likely(ret == good_frame))
  31 +               ret = enh_desc_coe_rdes0(!!(rdes0 & RDES0_IPC_CSUM_ERROR),
  32 +                                        !!(rdes0 & RDES0_FRAME_TYPE),
  33 +                                        !!(rdes0 & ERDES0_RX_MAC_ADDR));
  34
  35         if (unlikely(rdes0 & RDES0_DRIBBLING))
  36                 x->dribbling_bit++;
  37 --
  38 2.20.1
  39