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From:   Thomas Gleixner <tglx@linutronix.de>
To:     Radoslaw Biernacki <biernacki@google.com>,
        Paul Menzel <pmenzel@molgen.mpg.de>
Cc:     x86@kernel.org, Ross Zwisler <zwisler@google.com>,
        Daniel Drake <drake@endlessm.com>,
        Andy Lutomirski <luto@kernel.org>,
        Borislav Petkov <bp@alien8.de>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Len Brown <len.brown@intel.com>,
        Linux Upstreaming Team <linux@endlessm.com>,
        "Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
        Thorsten Leemhuis <regressions@leemhuis.info>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] x86/tsc: Use hard-coded crystal clock for Skylake mobile
In-Reply-To: <CAM4=Rn+7RGHEGa7u33zUA0b-cBehadw4NKN75JtjKjOhxm2Fxg@mail.gmail.com>
References: <20200509113717.9084-1-pmenzel@molgen.mpg.de> <87eerr3ppb.fsf@nanos.tec.linutronix.de> <edc5af47-27e6-753f-c095-bd3087942690@molgen.mpg.de> <CAM4=Rn+7RGHEGa7u33zUA0b-cBehadw4NKN75JtjKjOhxm2Fxg@mail.gmail.com>
Date:   Mon, 11 May 2020 14:34:41 +0200
Message-ID: <87y2py6466.fsf@nanos.tec.linutronix.de>
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Radoslaw Biernacki <biernacki@google.com> writes:
> We found that regression only on specific SKU which was used in one
> model of ChromeBook.
> What's interesting is that some other SKU is fine.
>
> The consequences of this are rather not trivial,
> so this was considered a quickfix and temporary till we develop
> something better.
> In contrast to ChromeOs, I know that there is no way of finding if
> there are in fact regressions on generic kernel in the field (this is
> SKU dependent),
> but we also think that this problem should be addressed in a better
> way (if possible).

Fix the BIOS to setup the CPUID/MSRs correctly?

Thanks,

        tglx