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Date: Fri, 19 Sep 2008 11:21:19 -0700 (PDT)
From: Thomas Gleixner <tglx@linutronix.de>
To: Andreas Herrmann <andreas.herrmann3@amd.com>
cc: Valdis.Kletnieks@vt.edu, Ingo Molnar <mingo@elte.hu>,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86: c1e_idle: don't mark TSC unstable if CPU has
 invariant TSC
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On Fri, 19 Sep 2008, Andreas Herrmann wrote:
> TSC on K8 is not P-state and C-state invariant.
> Thus on K8 you'll have a TSC drift if C1E is entered.
> 
> This means that if C1E is enabled TSC should be marked unstable on
> those CPUs (it shouldn't be used as a clocksource).

Correct. I missed that detail with the newer CPUs when I did the C1E
idle stuff. Thanks for catching it. I'll schedule it for Linus when
I'm back from Portland.

Thanks,

	tglx