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Message-ID: <fb32abc8-4381-00bf-c07e-b28066f51cdb@intel.com>
Date:   Wed, 13 Sep 2023 13:58:24 -0700
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Subject: Re: [PATCH 2/5] selftests/resctrl: Remove duplicate feature check
 from CMT test
Content-Language: en-US
To:     =?UTF-8?Q?Ilpo_J=c3=a4rvinen?= <ilpo.jarvinen@linux.intel.com>
CC:     Shuah Khan <shuah@kernel.org>,
        Shuah Khan <skhan@linuxfoundation.org>,
        <linux-kselftest@vger.kernel.org>,
        =?UTF-8?Q?Maciej_Wiecz=c3=b3r-Retman?= 
        <maciej.wieczor-retman@intel.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>,
        <stable@vger.kernel.org>
References: <20230911111930.16088-1-ilpo.jarvinen@linux.intel.com>
 <20230911111930.16088-3-ilpo.jarvinen@linux.intel.com>
 <40ba8890-32d1-e440-29fd-b8f8db69acc5@intel.com>
 <80695068-4a6-b8e9-107f-8d29ab3543be@linux.intel.com>
From:   Reinette Chatre <reinette.chatre@intel.com>
In-Reply-To: <80695068-4a6-b8e9-107f-8d29ab3543be@linux.intel.com>
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Hi Ilpo,

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@linux.intel.com>
>>> Cc: <stable@vger.kernel.org>
>>
>> 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@vger.kernel.org> # 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.

Reinette