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Date: Wed, 17 May 2017 17:03:02 +0200
From: Miroslav Lichvar <mlichvar@redhat.com>
To: John Stultz <john.stultz@linaro.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
        Richard Cochran <richardcochran@gmail.com>,
        Prarit Bhargava <prarit@redhat.com>,
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        Paul Mackerras <paulus@samba.org>, Anton Blanchard <anton@samba.org>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Tony Luck <tony.luck@intel.com>, Michael Ellerman <mpe@ellerman.id.au>,
        Fenghua Yu <fenghua.yu@intel.com>
Subject: Re: [PATCH 0/3] timekeeping: Improved NOHZ frequency steering (v2)
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On Fri, May 12, 2017 at 10:26:12AM -0700, John Stultz wrote:
> On Fri, May 12, 2017 at 8:14 AM, Miroslav Lichvar <mlichvar@redhat.com> wrote:
> > I see this with real PHCs and PTP/NTP synchronization too. It's very
> > confusing when the timekeeping changes so much for no apparent reason.
> > If we can't remove the old vsyscalls yet, I was thinking maybe a new
> > flag could be added to adjtimex to report the error, so applications
> > can at least detect this problem and consider stepping the clock in
> > order to reset the error?
> >
> > Thoughts?
> 
> I'd rather not have short-term hacks that applications have to adapt.
> So I think we should drop the old vsyscall method in the near term.
> Sorry this sort of fell off my radar.

Ok. Sounds good.

> Do you have an updated set of patches you want to get ready to address
> the issue? We can get those reviewed while we increase the pressure on
> dropping the OLD_VSYSCALL implementations.

I'll send an RFC series shortly.

Thanks,

-- 
Miroslav Lichvar