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Subject: Re: [PATCH] Close small window for vsyscall time inconsistencies
From: John Stultz <johnstul@us.ibm.com>
To: Andi Kleen <andi@firstfloor.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, Paul Mackerras <paulus@samba.org>,
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Date: Mon, 07 Apr 2008 09:32:42 -0700
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On Mon, 2008-04-07 at 13:27 +0200, Andi Kleen wrote:
> john stultz <johnstul@us.ibm.com> writes:
> >
> > The update_vsyscall then runs, and updates the clocksource frequency
> > with a slower frequency.
> 
> In the new code TSC should be only used on fixed-pstate TSC systems
> (cpufreq always marks it unstable), so that cannot really happen.

Sorry for being confusing here. This is not about hardware (TSC or
other) frequency changes, but the modification of the software's
representation of the frequency (as done w/ NTP adjustments).

thanks
-john