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From:   Daniel Drake <drake@endlessm.com>
Date:   Fri, 28 Jun 2019 15:26:07 +0800
Message-ID: <CAD8Lp4577Vd109p2ax22WtXUH=bEXYP8o8Ak5Gk9texCw9+x5Q@mail.gmail.com>
Subject: Re: [PATCH] x86: skip PIT initialization on modern chipsets
To:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>
Cc:     hpa@zytor.com, x86@kernel.org,
        Linux Upstreaming Team <linux@endlessm.com>,
        Linux Kernel <linux-kernel@vger.kernel.org>,
        "Wysocki, Rafael J" <rafael.j.wysocki@intel.com>,
        Hans de Goede <hdegoede@redhat.com>
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Oops, please also add a reference to the main thread:

On Fri, Jun 28, 2019 at 3:23 PM Daniel Drake <drake@endlessm.com> wrote:
> Detect modern setups where we have no need for the PIT (e.g. where
> we already know the TSC and LAPIC timer frequencies, so no need
> to calibrate them against the PIT), and skip initialization PIT in
> such cases.
>
> Skip the IO-APIC timer-checking code when we don't have a PIT
> to test against (this was causing the panic).

Link: https://lore.kernel.org/lkml/CAD8Lp45fedoPLnK=UmUhhtkjy5u2h04sYKrx3U+m04U6FpVZ4A@mail.gmail.com

> Tested-by: Daniel Drake <drake@endlessm.com>