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Date: Tue, 17 Jul 2012 00:05:15 +0300
From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
To: Andrew Morton <akpm@linux-foundation.org>,
        Pavel Emelyanov <xemul@openvz.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>,
        KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        "Dmitry V. Levin" <ldv@altlinux.org>,
        "Kirill A. Shutemov" <kirill@shutemov.name>,
        Doug Ledford <dledford@redhat.com>, linux-kernel@vger.kernel.org,
        containers@lists.linux-foundation.org
Subject: Re: [PATCH v2] ns: do not block exit_task_namespaces() for a long
 time
Message-ID: <20120716210515.GA17813@otc-wbsnb-06>
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On Mon, Jul 16, 2012 at 06:09:24PM +0300, Kirill A. Shutemov wrote:
> I also move synchronize_rcu() inside free_nsproxy(). It fixes racy
> put_nsproxy() which calls free_nsproxy() without synchronize_rcu().
> I guess it was missed during switch to RCU (see cf7b708).

I was wrong here. No races. RCU protects task->ns_proxy, not ns_proxy
itself.
Sorry for misleading.

--=20
 Kirill A. Shutemov

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