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Date: Fri, 17 Dec 2010 10:17:00 -0600
From: Serge Hallyn <serge.hallyn@canonical.com>
To: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>,
        LSM <linux-security-module@vger.kernel.org>,
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        kernel list <linux-kernel@vger.kernel.org>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Michael Kerrisk <michael.kerrisk@gmail.com>
Subject: Re: [RFC 1/5] user namespaces: Add a user_namespace as
 creator/owner of uts_namespace
Message-ID: <20101217161700.GA5926@peq>
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Quoting Alexey Dobriyan (adobriyan@gmail.com):
> On Fri, Dec 17, 2010 at 5:56 PM, Alexey Dobriyan <adobriyan@gmail.com> wrote:
> > On Fri, Dec 17, 2010 at 5:24 PM, Serge E. Hallyn <serge@hallyn.com> wrote:
> >> +/*
> >> + * userns count is 1 for root user, 1 for init_uts_ns,
> >> + * and 1 for... ?
> >> + */
> >>  struct user_namespace init_user_ns = {
> >>        .kref = {
> >> -               .refcount       = ATOMIC_INIT(2),
> >> +               .refcount       = ATOMIC_INIT(3),
> >
> > +1 is for init_nsproxy ;-)
> 
> Err, no.
> 
> +1 is to ensure it's never freed, but since allocator will BUG_ON (?) if fed
> with static object, maybe it's completely bogus.

Right.  On the one hand so long as it's high enough it doesn't really matter.
But I think it's worth getting the # exactly right in order to help document
what's going on.  So I'll try dropping it back down to 2.

thanks,
-serge