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Date: Wed, 17 Feb 2016 15:20:05 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>,
        Intel graphics driver community testing & development 
	<intel-gfx@lists.freedesktop.org>,
        Linux kernel development <linux-kernel@vger.kernel.org>,
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        "Gautham R. Shenoy" <ego@linux.vnet.ibm.com>,
        Chris Wilson <chris@chris-wilson.co.uk>,
        Daniel Vetter <daniel@ffwll.ch>
Subject: Re: [PATCH] [RFC] kernel/cpu: Use lockref for online CPU reference
 counting
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On Wed, Feb 17, 2016 at 02:47:31PM +0200, Joonas Lahtinen wrote:
> On ti, 2016-02-16 at 12:07 +0100, Peter Zijlstra wrote:
> > On Tue, Feb 16, 2016 at 12:51:03PM +0200, Joonas Lahtinen wrote:
> > > Quoting my original patch;
> > > 
> > > "See the Bugzilla link for more details.
> > 
> > If its not in the Changelog it doesn't exist. Patches should be self
> > contained and not refer to external sources for critical information.
> 
> The exact locking case in CPUfreq drivers causing a splat is described
> in the patch. Details were already included, that's why term "more
> details" was used.

Barely. What was not described was why you went to tinker with the
hotplug lock instead of sanitizing cpufreq. Nor why your chosen solution
is good.

> This is not exactly taking us closer to a fix, 

Why you think we can discuss fixes if you've not actually described your
problem is beyond me.