Re: [PATCH V1 net-next 0/5] Add devlink support to ena

[Jakub Kicinski <kuba@kernel.org>]

On Wed, 11 Jan 2023 21:21:16 +0000 Arinzon, David wrote:
> I'll note again that this is not a configurable value, meaning, the only option is
> to have 128B (standard) or 256B (large) LLQ, there's no option to set other values,
> but only choose between the modes, therefore, I don't see how having such an
> option through ethtool, as you suggested (setting the max length) can be
> beneficial in our use-case (might be good overall, as you noted, it's a more
> generic concept). Will put more thought into it.

FWIW you can just return an error via extack if user tries to set an
unsupported value, like:

	NL_SET_ERR_MSG(extack, "only X and Y are supported");

and it will pop up as part of the error in ethtool CLI. Or do some
rounding up - a lot of drivers does that for ring params already.