Re: [PATCH net-next 1/3] selftests: drv-net: Introduce a selftest for ethtool flow control

[Jakub Kicinski <kuba@kernel.org>]

On Sun, 20 Sep 2026 18:47:27 +0200 Maxime Chevallier (Netdev
Foundation) wrote:
> Future ethtool selftests are expected to use the same, these helpers
> are put in the net selftest lib.

Please resist the urge to create libraries.

If you're doing this I suspect you didn't even read the README and 
you expect people to search around for libraries?

Put the code in your test, the duplication doesn't matter.
If you _absolutely have to_ you can create a local lib under
tools/testing/selftests/drivers/net/hw/ but please think really 
hard before you do.

> +    :param cfg: test config

If you have nothing to say - don't say anything 🤷️

> +    :returns: tuple containing :
> +              - return code of the ethtool command,
> +              - rx status,
> +              - tx status,
> +              - aneg status

Have you seen much code in netdev selftests using this style 
of comments?

> +        defer(cmd, f"ethtool -s {cfg.ifname} autoneg on", fail=False)

Why are you putting fail=False on the defers? IIRC defer errors are
logged and ignored. Is ethtool reporting an error when there's nothing
to change?

Those are just some things that immediately jump out :)
Please also fix the pylint --disable=R issues?