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Message-ID: <83cbd5ce-7f00-9121-44b3-5d1b94d66f02@suse.com>
Date:   Wed, 25 May 2022 10:37:53 +0200
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Subject: Re: [PATCH 2/2] x86/pat: add functions to query specific cache mode
 availability
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To:     Thorsten Leemhuis <regressions@leemhuis.info>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Jani Nikula <jani.nikula@linux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@intel.com>,
        Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        xen-devel@lists.xenproject.org, x86@kernel.org,
        linux-kernel@vger.kernel.org, intel-gfx@lists.freedesktop.org,
        dri-devel@lists.freedesktop.org, Juergen Gross <jgross@suse.com>,
        Chuck Zmudzinski <brchuckz@netscape.net>,
        regressions@lists.linux.dev, stable@vger.kernel.org
References: <20220503132207.17234-1-jgross@suse.com>
 <20220503132207.17234-3-jgross@suse.com>
 <1d86d8ff-6878-5488-e8c4-cbe8a5e8f624@suse.com>
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 <77255e5b-12bf-5390-6910-dafbaff18e96@netscape.net>
 <a2e95587-418b-879f-2468-8699a6df4a6a@suse.com>
 <8b1ebea5-7820-69c4-2e2b-9866d55bc180@netscape.net>
 <c5fa3c3f-e602-ed68-d670-d59b93c012a0@netscape.net>
 <3bff3562-bb1e-04e6-6eca-8d9bc355f2eb@suse.com>
 <3ca084a9-768e-a6f5-ace4-cd347978dec7@netscape.net>
 <9af0181a-e143-4474-acda-adbe72fc6227@suse.com>
 <b2585c19-d38b-9640-64ab-d0c9be24be34@netscape.net>
 <dae4cc45-a1cd-e33f-25ef-c536df9b49e6@leemhuis.info>
 <3fc70595-3dcc-4901-0f3f-193f043b753f@netscape.net>
 <eab9fdb0-11ef-4556-bdd7-f021cc5f10b7@leemhuis.info>
From:   Jan Beulich <jbeulich@suse.com>
In-Reply-To: <eab9fdb0-11ef-4556-bdd7-f021cc5f10b7@leemhuis.info>
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On 25.05.2022 09:45, Thorsten Leemhuis wrote:
> On 24.05.22 20:32, Chuck Zmudzinski wrote:
>> On 5/21/22 6:47 AM, Thorsten Leemhuis wrote:
>>> I'm not a developer and I'm don't known the details of this thread and
>>> the backstory of the regression, but it sounds like that's the approach
>>> that is needed here until someone comes up with a fix for the regression
>>> exposed by bdd8b6c98239.
>>>
>>> But if I'm wrong, please tell me.
>>
>> You are mostly right, I think. Reverting bdd8b6c98239 fixes
>> it. There is another way to fix it, though.
> 
> Yeah, I'm aware of it. But it seems...
> 
>> The patch proposed
>> by Jan Beulich also fixes the regression on my system, so as
>> the person reporting this is a regression, I would also be satisfied
>> with Jan's patch instead of reverting bdd8b6c98239 as a fix. Jan
>> posted his proposed patch here:
>>
>> https://lore.kernel.org/lkml/9385fa60-fa5d-f559-a137-6608408f88b0@suse.com/
> 
> ...that approach is not making any progress either?
> 
> Jan, can could provide a short status update here? I'd really like to
> get this regression fixed one way or another rather sooner than later,
> as this is taken way to long already IMHO.

What kind of status update could I provide? I've not heard back from
anyone of the maintainers, so I have no way to know what (if anything)
I need to do.

Jan