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Date:   Tue, 31 Oct 2023 12:41:16 -0400
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Subject: Re: [PATCH] drm/amd/display: remove redundant check
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To:     =?UTF-8?Q?Jos=C3=A9_Pekkarinen?= <jose.pekkarinen@foxhound.fi>,
        Greg KH <gregkh@linuxfoundation.org>
Cc:     harry.wentland@amd.com, sunpeng.li@amd.com,
        Rodrigo.Siqueira@amd.com, skhan@linuxfoundation.org,
        dillon.varone@amd.com,
        linux-kernel-mentees@lists.linuxfoundation.org,
        dri-devel@lists.freedesktop.org, Xinhui.Pan@amd.com,
        linux-kernel@vger.kernel.org, samson.tam@amd.com,
        SyedSaaem.Rizvi@amd.com, stable@vger.kernel.org, daniel@ffwll.ch,
        george.shen@amd.com, alexander.deucher@amd.com, Jun.Lei@amd.com,
        airlied@gmail.com, christian.koenig@amd.com
References: <20231030171748.35482-1-jose.pekkarinen@foxhound.fi>
 <2023103115-obstruct-smudgy-6cc6@gregkh>
 <3ab58c1e48447798d7525e7d2f42f1a2@foxhound.fi>
 <2023103141-clear-scale-897a@gregkh>
 <1175edcbdf0d0a55d39a87f220259528@foxhound.fi>
From:   Aurabindo Pillai <aurabindo.pillai@amd.com>
In-Reply-To: <1175edcbdf0d0a55d39a87f220259528@foxhound.fi>
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On 2023-10-31 08:32, José Pekkarinen wrote:
> On 2023-10-31 14:20, Greg KH wrote:
>> On Tue, Oct 31, 2023 at 01:42:17PM +0200, José Pekkarinen wrote:
>>> On 2023-10-31 07:48, Greg KH wrote:
>>> > On Mon, Oct 30, 2023 at 07:17:48PM +0200, José Pekkarinen wrote:
>>> > > This patch addresses the following warning spotted by
>>> > > using coccinelle where the case checked does the same
>>> > > than the else case.
>>> > >
>>> > > 
>>> drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_util_32.c:4664:8-10:
>>> > > WARNING: possible condition with no effect (if == else)
>>> > >
>>> > > Fixes: 974ce181 ("drm/amd/display: Add check for PState change in
>>> > > DCN32")
>>> > >
>>> > > Cc: stable@vger.kernel.org
>>> >
>>> > Why is this relevant for stable?
>>>
>>>     Hi,
>>>
>>>     I was asked to send it for stable because this code
>>> looks different in amd-staging-drm-next, see here.
>>>
>>> https://gitlab.freedesktop.org/agd5f/linux/-/blob/amd-staging-drm-next/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_util_32.c#L4661
>>
>> I don't know what I am looking at, sorry.
>>
>>>     Feel free to let me know if this is wrong, or if I
>>> need to review some other guidelines I may have missed.
>>
>> Please see the list of rules for stable patches:
>> https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
>>
>> Does "remove code that does nothing" fit here?
> 
>      Yep, it is a trivial fix which compilers should be able
> to optimize, so no real benefit to the user. Sorry Greg!
> 
>      José.

Hi Greg,

Sorry, I asked José to send it to stable because I realized the patch 
listed in the fixes tag wasnt quite needed on stable. Patch from José 
effectively removes it.

I hope that clears the context. But there is no impact whether you apply 
José's patch or not, so we're good either way.