Re: [PATCH net-next] selftests: drv-net: hide the devlink port_split test

[Petr Machata <petrm@nvidia.com>]

Jakub Kicinski <kuba@kernel.org> writes:

> The devlink port_split test has limited applicability.
> NICs (as opposed to switches) require at least a re-probe
> to apply the split configuration.

Interesting, apparently some NICs require reboot after devlink port
split. Hmm, should I just move the test to drivers/mlxsw?

> On top of that the test is not compatible with our driver env,
> it just splits all ports on the system, not only what NETIF
> points at.
>
> Long term we may want to add some indication in devlink whether
> the port splitting is runtime (cmode of sorts), and fix the
> test to follow driver env. But since no (known) NIC driver can
> support runtime anyway let's just hide the test from the selftest
> framework by moving it to extra files.

Sure, go for it.

> Having this test randomly break unrelated NICs within the DUT
> makes people implement allow-lists for ksft, which then means
> their setups don't run new tests.

So I'm fine with the patch, but I don't buy this argument. People
presumably understand that allow-listing implies that only the, well,
allowed tests will be run. Presumably there was a history of new stuff
blowing up, or gradual enablement or whatever, otherwise why not just
blacklist the one problematic one? I.e. don't blame the existence of
allow-lists on devlink_port_split.

> Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Reviewed-by: Petr Machata <petrm@nvidia.com>

> ---
> CC: danieller@nvidia.com
> CC: petrm@nvidia.com
> CC: shuah@kernel.org
> CC: linux-kselftest@vger.kernel.org
> ---
>  tools/testing/selftests/drivers/net/hw/Makefile | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/drivers/net/hw/Makefile b/tools/testing/selftests/drivers/net/hw/Makefile
> index 234db5c2c90c..ab13f58d703e 100644
> --- a/tools/testing/selftests/drivers/net/hw/Makefile
> +++ b/tools/testing/selftests/drivers/net/hw/Makefile
> @@ -19,7 +19,6 @@ TEST_GEN_FILES := \
>  
>  TEST_PROGS = \
>  	csum.py \
> -	devlink_port_split.py \
>  	devlink_rate_cross_esw.py \
>  	devlink_rate_tc_bw.py \
>  	devmem.py \
> @@ -55,6 +54,7 @@ TEST_PROGS = \
>  	#
>  
>  TEST_FILES := \
> +	devlink_port_split.py \
>  	devmem_lib.py \
>  	ethtool_lib.sh \
>  	#