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Message-ID: <1455713251.5622.9.camel@linux.intel.com>
Subject: Re: [PATCH] [RFC] kernel/cpu: Use lockref for online CPU reference
 counting
From: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
To: Peter Zijlstra <peterz@infradead.org>, Oleg Nesterov <oleg@redhat.com>
Cc: Intel graphics driver community testing & development 
	<intel-gfx@lists.freedesktop.org>,
        Linux kernel development <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        David Hildenbrand <dahi@linux.vnet.ibm.com>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        "Gautham R. Shenoy" <ego@linux.vnet.ibm.com>,
        Chris Wilson <chris@chris-wilson.co.uk>,
        Daniel Vetter <daniel@ffwll.ch>
Date: Wed, 17 Feb 2016 14:47:31 +0200
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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.

This is not exactly taking us closer to a fix, so I'd rather like to
discuss about the possibility of adding one more member to task_struct.
I added Oleg as CC to catch his attention to re-evaluate based on the
previous discussion in this thread.

Regards, Joonas

-- 
Joonas Lahtinen
Open Source Technology Center
Intel Corporation