Re: [LTP] [PATCH 1/1] doc/ground_rules: Add Kernel features check rules

Li Wang via ltp
2026-01-28T09:01:15Z

Hi Petr,

Generally looks good, just a few comments to polish it.

Reviewed-by: Li Wang <liwang@redhat.com>

On Wed, Jan 28, 2026 at 4:01 PM Petr Vorel <pvorel@suse.cz> wrote:

> Signed-off-by: Petr Vorel <pvorel@suse.cz>
> ---
> Based on a discussion various discussions:
> https://lore.kernel.org/ltp/20260123122545.GA122331@pevik/
> https://lore.kernel.org/ltp/20260128072445.GB13495@pevik/
>
> Kind regards,
> Petr
>
> doc/developers/ground_rules.rst | 17 +++++++++++++++++
> 1 file changed, 17 insertions(+)
>
> diff --git a/doc/developers/ground_rules.rst
> b/doc/developers/ground_rules.rst
> index 05e473cad5..90fe7a64ee 100644
> --- a/doc/developers/ground_rules.rst
> +++ b/doc/developers/ground_rules.rst
> @@ -174,3 +174,20 @@ These patches should also add a [STAGING] keyword
> into the patch subject, e.g.
> In a case that a test for unreleased kernel is really needed to be merged
> we do
> not add it to the list of test executed by default and keep it in
> :master:`runtest/staging` file until the kernel code is finalized.
> +
> +Kernel features check
> +---------------------
> +
> +We prefer to use :c:type:`.needs_kconfigs <tst_test>` (kernel kconfig
> check).
> +But do *not* use it when there is another way to detect the functionality
> (e.g.
> +via detecting functionality via ``/proc|sys``) *and* any of these rules
> applies:
>

Perhaps replace "detect" with "impact"?

> +- Kernel allows to disable functionality via `kernel’s command-line
> parameter
> + <
> https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html
> >`_
> + (it can be disabled in runtime).
>

- Runtime-disable possible: kernel exposes a command-line parameter
(or runtime knob) that can enable/disable the functionality, so a
build-time
kconfig does not reflect runtime availability.

+- It's a check for a functionality which can be compiled as module
> + (`tristate
> + <https://docs.kernel.org/kbuild/kconfig-language.html#menu-attributes
> >`_,
> + modul might not be available).
>

- Tristate/module feature: The functionality is controlled by a
`tristate <
https://docs.kernel.org/kbuild/kconfig-language.html#menu-attributes>`_
option (i.e. it may be built as a module), and the module might not be
present
or loaded at runtime.

> +- New kernel functionality which is unlikely to be backported (use
> + :c:type:`.min_kver <tst_test>` instead).

- New non-backported functionality: The test targets a new upstream kernel
feature
that is unlikely to be backported. Prefer :c:type:`.min_kver <tst_test>`
for gating
instead of Kconfig symbols.

--
Regards,
Li Wang