[PATCH net-next v2 02/15] net: ethernet: mtk_eth_soc: unmap RX data before calling build_skb

From: Ilya Lipnitskiy
Date: Fri Apr 23 2021 - 01:21:25 EST


From: Felix Fietkau <nbd@xxxxxxxx>

Since build_skb accesses the data area (for initializing shinfo), dma unmap
needs to happen before that call

Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
[Ilya: split build_skb cleanup fix into a separate commit]
Signed-off-by: Ilya Lipnitskiy <ilya.lipnitskiy@xxxxxxxxx>
---
drivers/net/ethernet/mediatek/mtk_eth_soc.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index b2175ec451ab..540003f3fcb8 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -1298,6 +1298,9 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget,
goto release_desc;
}

+ dma_unmap_single(eth->dev, trxd.rxd1,
+ ring->buf_size, DMA_FROM_DEVICE);
+
/* receive data */
skb = build_skb(data, ring->frag_size);
if (unlikely(!skb)) {
@@ -1307,8 +1310,6 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget,
}
skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);

- dma_unmap_single(eth->dev, trxd.rxd1,
- ring->buf_size, DMA_FROM_DEVICE);
pktlen = RX_DMA_GET_PLEN0(trxd.rxd2);
skb->dev = netdev;
skb_put(skb, pktlen);
--
2.31.1