RTE_ETH_RSS_IP support by Intel NIC drivers

[Bruce Richardson]

On Fri, Jun 20, 2025 at 12:24:24PM +0200, Morten Brørup wrote:
> Don't the Intel i40e and e1000 drivers support RSS on IP addresses [1]?
> It looks like they do, but don't report it.
> 
> For i40e:
> Accepted: 0x2288 FRAG_IPV4 NONFRAG_IPV4_OTHER FRAG_IPV6 NONFRAG_IPV6_OTHER
> Unsupported: 0x8104 IPV4 IPV6 IPV6_EX
> 

That looks like a miss on our part. I'll log an internal bug and we can
investigate.

> For e1000:
> Accepted: 0x8104 IPV4 IPV6 IPV6_EX
> Unsupported: 0x2288 FRAG_IPV4 NONFRAG_IPV4_OTHER FRAG_IPV6 NONFRAG_IPV6_OTHER
> 

The e1000 driver, is actually a small collection of slightly different, but
related drivers for 1G HW - some of which are quite basic. I'm not sure
what the specific capabilities of the various HW NICs are, but again, we'll
take a look and see if we are missing some things.

> The RSS offload types [2] have no descriptions, so it's hard to guess which alternatives would be viable.
> 
> [1]: https://elixir.bootlin.com/dpdk/v25.03/source/lib/ethdev/rte_ethdev.h#L783
> [2]: https://elixir.bootlin.com/dpdk/v25.03/source/lib/ethdev/rte_ethdev.h#L553
> 
> -Morten
>