Re: [PATCH net v2 4/4] net: ethernet: cortina: Handle large frames

From: Vladimir Oltean
Date: Mon Nov 06 2023 - 08:43:39 EST


On Mon, Nov 06, 2023 at 03:26:26PM +0200, Vladimir Oltean wrote:
> Gemini should never attempt to provide checksums for DSA-tagged packets
> unless it is able to take skb->csum_start into consideration, otherwise
> it will get it wrong.

Additionally, since Gemini does not put NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM
in vlan_features, DSA won't inherit (thus won't have) them. So,
validate_xmit_skb() should perform the skb checksum during the xmit on
the user port, which is earlier compared to the xmit on the conduit.
So, I guess skb->ip_summed should already be CHECKSUM_NONE here?
I think the only problem for DSA is the lack of the TSS_BYPASS_BIT. The
rest is unrelated.