Re: [PATCH net-next V2 11/11] net/mlx5e: Support ethtool tcp-data-split settings

From: Gal Pressman
Date: Wed May 28 2025 - 01:11:14 EST


On 27/05/2025 19:10, Jakub Kicinski wrote:
> On Thu, 22 May 2025 16:19:28 -0700 Saeed Mahameed wrote:
>>> Why are you modifying wanted_features? wanted_features is what
>>> *user space* wanted! You should probably operate on hw_features ?
>>> Tho, may be cleaner to return an error and an extack if the user
>>> tries to set HDS and GRO to conflicting values.
>>>
>>
>> hw_features is hw capabilities, it doesn't mean on/off.. so no we can't
>> rely on that.
>>
>> To enable TCP_DATA_SPLIT we tie it to GRO_HW, so we enable GRO_HW when
>> TCP_DATA_SPLIT is set to on and vise-versa. I agree not the cleanest..
>> But it is good for user-visibility as you would see both ON if you query
>> from user, which is the actual state. This is the only way to set HW_GRO
>> to on by driver and not lose previous state when we turn the other bit
>> on/off.
>
> features = on
> hw_features = off
>
> is how we indicate the feature is "on [fixed]"
> Tho, I'm not sure how much precedent there is for making things fixed
> at runtime.

Isn't this something that should be handled through fix_features?