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Date: Tue, 22 Jul 2014 10:00:16 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>, Thomas Gleixner <tglx@linutronix.de>,
        x86-ml <x86@kernel.org>, lkml <linux-kernel@vger.kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [PATCH] x86, TSC: Add a software TSC offset
Message-ID: <20140722080016.GY3935@laptop>
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On Mon, Jul 21, 2014 at 03:13:33PM -0700, Andy Lutomirski wrote:
> >> I actually own one of these systems.  It's a Sandy Bridge Core-i7
> >> Extreme or something like that.
> >
> > Ha, cool, so I've got my tester! :-)
> 
> Ha.  Ha ha.  Muahaha.  Because IIRC this box is synced until the first
> time it suspends.

Oh cute, one of those :-) Yes some BIOSes write 'random' crap into the
TSC when doing the S states jig. We have some tsc suspend/resume hooks
to correct the worst of that, but yeah screwy that.