Re: [PATCH 2/5] selftests/resctrl: Remove duplicate feature check from CMT test

From: Ilpo Järvinen
Date: Thu Sep 14 2023 - 05:58:38 EST


On Wed, 13 Sep 2023, Reinette Chatre wrote:
> On 9/13/2023 4:11 AM, Ilpo Järvinen wrote:
> > On Tue, 12 Sep 2023, Reinette Chatre wrote:
> >> On 9/11/2023 4:19 AM, Ilpo Järvinen wrote:
> >>> The test runner run_cmt_test() in resctrl_tests.c checks for CMT
> >>> feature and does not run cmt_resctrl_val() if CMT is not supported.
> >>> Then cmt_resctrl_val() also check is CMT is supported.
> >>>
> >>> Remove the duplicated feature check for CMT from cmt_resctrl_val().
> >>>
> >>> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
> >>> Cc: <stable@xxxxxxxxxxxxxxx>
> >>
> >> This does not look like stable material to me.
> >
> > I know but when constructing this series I had 2 options:
> >
> > Either convert also this when changing validate_resctrl_feature_request()
> > or remove this call entirely.
> >
> > Given it's duplicate of the other CMT check, I chose to just remove it
> > (which I'd do anyway). As patch 4/5 requires 3/5 which in turn requires
> > this, this has to go stable if 4/5 goes too.
> >
>
> Understood. This makes it a dependency of an actual fix, which is addressed
> in 4/5's sign-off area. This notation is new to me but it is not clear to me
> that the dependency should also be tagged as stable material (without a
> fixes tag). Since it is not an actual fix by itself yet is sent to @stable
> I think it may cause confusion. Is just listing it as a dependency of the
> actual fix not sufficient (as you already do in 4/5)? Perhaps as compromise
> this patch can also get a note to the stable team. Something like:
>
> Cc: <stable@xxxxxxxxxxxxxxx> # dependency of "selftests/resctrl: Fix feature checks"
>
> I am not sure though - I would like to avoid confusion and not burden
> the stable team. If this is a flow you have used before successfully I'd
> defer to your experience.

I came across that dependency format when Greg KH replied to somebody how
to deal with the cases where there isn't yet a commit id
(the cases mentioned in Documentation/process/stable-kernel-rules.rst
assumes there is already a commit id). Unfortunately it's long time ago
so I cannot easily find the link.

Documentation/process/stable-kernel-rules.rst doesn't state that the
stable address should be only used for the patches with Fixes. In general,
I believe this doesn't matter much because whether something is Cc'ed or
not to stable@xxxxxxxxxxxxxxx doesn't seems to impact the decision if a
patch goes into stable or not (even if even some maintainers seem to
pretend leaving it out makes a difference so I tend to play along and
smile myself how incorrect that assumption is :-)).


--
i.