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Date:   Fri, 23 Sep 2022 18:30:13 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     K Prateek Nayak <kprateek.nayak@amd.com>
Cc:     linux-kernel@vger.kernel.org, rafael@kernel.org, lenb@kernel.org,
        linux-acpi@vger.kernel.org, linux-pm@vger.kernel.org,
        dave.hansen@linux.intel.com, tglx@linutronix.de, andi@lisas.de,
        puwen@hygon.cn, mario.limonciello@amd.com, peterz@infradead.org,
        rui.zhang@intel.com, gpiccoli@igalia.com,
        daniel.lezcano@linaro.org, ananth.narayan@amd.com,
        gautham.shenoy@amd.com, Calvin Ong <calvin.ong@amd.com>,
        "Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
        stable@vger.kernel.org
Subject: Re: [PATCH v2] x86,acpi: Limit "Dummy wait" workaround to older AMD
 and Intel processors
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On Fri, Sep 23, 2022 at 09:55:02PM +0530, K Prateek Nayak wrote:
> Yes, I did see the patch, but Andreas replied to Dave's patch attached
> in v1 saying that he had seen this issue with AMD Athlon on a VIA
> chipset back in 2006. (https://lore.kernel.org/lkml/Yyy6l94G0O2B7Yh1@rhlx01.hs-esslingen.de/)
> Therefore, Dave's patch is not sufficient.

Well, AFAICT, that box is old and dead. And I'm being told that the AMD
machines which we care for and which are still alive should not need the
dummy read.

Which means, we could try the simple fix first and see who complains.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette