Re: [PATCH net] selftests: drv-net: pause: Skip support tests without link autonegotiation

[Maxime Chevallier <maxime.chevallier@bootlin.com>]

Hi,

On 10/30/26 18:35, Mohsin Bashir wrote:
> From: Mohsin Bashir <hmohsin@meta.com>
> 
> Devices without link autonegotiation support may reject both link-setting
> requests in pause_test_support(). On fbnic, all four variants then fail
> in cleanup when the deferred restore of unchanged link settings returns
> EOPNOTSUPP. Removing the restore alone would report PASS without running
> any pause checks.
> 
> Fix this by calling require_link_autoneg() before pause_setup() to skip
> the test when either interface lacks link autonegotiation support. This
> also skips devices that support only forced link configuration.
> 
> The issue was observed in the fbnic CI/CD pipeline. It was reproduced and
> the fix was tested on a local fbnic device.
> 
> Fixes: cbd8a536cd6d ("selftests: drv-net: Introduce a selftest for ethtool flow control")
> Signed-off-by: Mohsin Bashir <hmohsin@meta.com>
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> ---
>  tools/testing/selftests/drivers/net/hw/pause.py | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/tools/testing/selftests/drivers/net/hw/pause.py b/tools/testing/selftests/drivers/net/hw/pause.py
> index ca4a55e59c30..1537f88e0e77 100755
> --- a/tools/testing/selftests/drivers/net/hw/pause.py
> +++ b/tools/testing/selftests/drivers/net/hw/pause.py
> @@ -466,6 +466,7 @@ def pause_test_support(cfg, pauseparams):
>      supported fields.
>      """
>  
> +    require_link_autoneg(cfg)

This helper checks if the remote supports aneg too, so it's too restrictive.

The goal of this test is to check the local device's behaviour, without too
much dependencies on the remote, so that we can at least have it test some of
the local driver behaviour even when it's connected to a dumb remote or a switch.

Maybe the sane thing to do is to allows the defer() calls in pause_setup() to
fail silently with "fail=False" ?

Or maybe a bit more clever, have a quick check to see if the device accepts
an ethtool -s XXX command ? looks like fbnic will refuse all of'em as it
doesn't have a .set_link_ksettings.

Maxime