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Date: Thu, 5 Apr 2007 01:10:21 -0700
From: "Paul Menage" <menage@google.com>
To: vatsa@in.ibm.com
Subject: Re: [PATCH] Fix race between attach_task and cpuset_exit
Cc: "Paul Jackson" <pj@sgi.com>, akpm@linux-foundation.org,
       linux-kernel@vger.kernel.org, "Balbir Singh" <balbir@in.ibm.com>
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On 4/5/07, Srivatsa Vaddagiri <vatsa@in.ibm.com> wrote:
>
> Hmm yes ..I am surprised we arent doing a synhronize_rcu in
> cpuset_rmdir() before dropping the dentry. Did you want to send a patch
> for that?

Currently cpuset_exit() isn't in a rcu section so it wouldn't help.

But this ceases to be a problem if we don't leave the refcount
dropping in cpuset_exit() where it is currently - it doesn't drop the
refcount until it's holding manage_mutex, at which point it's safe to
hold a cpuset reference with a refcount of 0.

Paul