Date: Fri, 22 Feb 2008 09:37:52 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: ebiederm@xmission.com (Eric W. Biederman)
Cc: Oleg Nesterov <oleg@tv-sign.ru>, Valdis.Kletnieks@vt.edu,
       Andrew Morton <akpm@linux-foundation.org>, roland@redhat.com,
       linux-kernel@vger.kernel.org, Pavel Emelyanov <xemul@openvz.org>,
       Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Subject: Re: tty && pid problems
Message-ID: <20080222093752.09dbfc53@core>
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> > I've added locks in my test tree and now I've finally got -mm to build
> > will do some testing then push more stuff upstream
> 
> Thanks.  At the tty layer that was probably me.
> Most of the instances already appear to be nested in some other kind of
> locking, but that doesn't make no additional locking correct or ensure
> that it will give a uniform result.

Fortunately your pid struct is ref counted so not too hard to sort out.
Need to look at procfs but at worst tty needs to export a function which
returns a reference bumped pid struct to people who stick their nose in
from outside.

Alan
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