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From: Michael Ellerman <mpe@ellerman.id.au>
To: John Stultz <john.stultz@linaro.org>,
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Cc: John Stultz <john.stultz@linaro.org>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@kernel.org>,
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        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Tony Luck <tony.luck@intel.com>, Fenghua Yu <fenghua.yu@intel.com>
Subject: Re: [RFC][PATCH] time: Add warning about imminent deprecation of CONFIG_GENERIC_TIME_VSYSCALL_OLD
In-Reply-To: <1494613450-4713-1-git-send-email-john.stultz@linaro.org>
References: <1494613450-4713-1-git-send-email-john.stultz@linaro.org>
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Date: Mon, 22 May 2017 10:58:50 +1000
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John Stultz <john.stultz@linaro.org> writes:

> CONFIG_GENERIC_TIME_VSYSCALL_OLD was introduced five years ago
> to allow a transition from the old vsyscall implementations to
> the new method (which simplified internal accounting and made
> timekeeping more precise).

I'm sure it's completely obvious to everyone except me what needs to be
done, but can you spell it out for me? Keeping in mind that I don't know
anything about the time keeping code.

> However, PPC and IA64 have yet to make the transition, despite
> in some cases me sending test patches to try to help it along.
>
> http://patches.linaro.org/patch/30501/
> http://patches.linaro.org/patch/35412/

I've never seen a PPC patch, did you send one?

> If its helpful, my last pass at the patches can be found here:
> https://git.linaro.org/people/john.stultz/linux.git dev/oldvsyscall-cleanup

Looks like it's just a draft for PPC. Do you think that should work and
it just needs testing? The comment about the vdso being "slightly
behind" is a little concerning.

cheers