Re: [PATCH net v5] net: stmmac: remove software VLAN tag stripping

The software VLAN stripping logic in stmmac_rx_vlan() was originally
introduced in 2014 by commit b93819854d6e ("stmmac: Add vlan rx for
better GRO performance.") as a workaround to improve GRO performance,
since at that time GRO could not handle frames with VLAN tags. However,
this limitation was resolved in 2015 by commit 66e5133f19e9 ("vlan: Add
GRO support for non hardware accelerated vlan"), which added GRO support
for non-hardware-accelerated VLAN frames. Keeping a software fallback
path for VLAN stripping is no longer necessary and only adds complexity.

Fixes: b93819854d6e ("stmmac: Add vlan rx for better GRO performance.")
Signed-off-by: Peilin He <redacted>
Reviewed-by: xu xin <redacted>
Reviewed-by: Jiang Kun <redacted>
---
../net/ethernet/stmicro/stmmac/stmmac_main.c | 28 ++-----------------
1 file changed, 2 insertions(+), 26 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index b2b7d0242dd3..2e3b0cf10d66 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -5021,24 +5021,6 @@ static netdev_features_t stmmac_features_check(struct sk_buff *skb,

return vlan_features_check(skb, features);
}

-static void stmmac_rx_vlan(struct net_device *dev, struct sk_buff *skb)
-{
-   struct vlan_ethhdr *veth = skb_vlan_eth_hdr(skb);
-   __be16 vlan_proto = veth->h_vlan_proto;
-   u16 vlanid;
-
-   if ((vlan_proto == htons(ETH_P_8021Q) &&
-        dev->features & NETIF_F_HW_VLAN_CTAG_RX) ||
-       (vlan_proto == htons(ETH_P_8021AD) &&
-        dev->features & NETIF_F_HW_VLAN_STAG_RX)) {
-       /* pop the vlan tag */
-       vlanid = ntohs(veth->h_vlan_TCI);
-       memmove(skb->data + VLAN_HLEN, veth, ETH_ALEN * 2);
-       skb_pull(skb, VLAN_HLEN);
-       __vlan_hwaccel_put_tag(skb, vlan_proto, vlanid);
-   }
-}