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Date: Tue, 12 Mar 2013 17:21:19 +0100
From: Michal Hocko <mhocko@suse.cz>
Subject: [PATCH -v2] device: separate all subsys mutexes (was: Re: [BUG]
 potential deadlock led by cpu_hotplug lock (memcg involved))
Message-ID: <20130312162119.GB5963@dhcp22.suse.cz>
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To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Li Zefan <lizefan@huawei.com>, LKML <linux-kernel@vger.kernel.org>, cgroups <cgroups@vger.kernel.org>, linux-mm@kvack.org, KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>, Johannes Weiner <hannes@cmpxchg.org>, Andrew Morton <akpm@linux-foundation.org>, Jiri Kosina <jkosina@suse.cz>, Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@redhat.com>, Kay Sievers <kay.sievers@vrfy.org>

On Tue 12-03-13 06:34:46, Greg Kroah-Hartman wrote:
> On Tue, Mar 12, 2013 at 02:05:04PM +0100, Michal Hocko wrote:
> > The fix is quite simple. We can pull the key inside bus_type structure
> > because they are defined per device so the pointer will be unique as
> > well. bus_register doesn't need to be a macro anymore so change it
> > to the inline. We could get rid of __bus_register as there is no other
> > caller but maybe somebody will want to use a different key so keep it
> > around for now.
> 
> Nice work, but just drop __bus_register(), no one should need to use a
> new key for this type of thing, now that you have added a per-bus_type
> variable.

OK v2 below. I have also ranamed __key to lock_key. Who is going to take
the patch?
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