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Date: Wed, 11 Feb 2015 00:17:04 -0500
From: Tejun Heo <tj@kernel.org>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>, Richard Weinberger <richard@nod.at>,
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        Andy Lutomirski <luto@amacapital.net>,
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        Ingo Molnar <mingo@redhat.com>
Subject: Re: [PATCHv3 8/8] cgroup: Add documentation for cgroup namespaces
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Hey,

On Tue, Feb 10, 2015 at 11:02:40PM -0600, Eric W. Biederman wrote:
> A slightly off topic comment, for where this thread has gone but
> relevant if we are talking about cgroup namespaces.
> 
> If don't implement compatibility with existing userspace, they get a
> nack.  A backwards-incompatible change should figure out how to remove
> the need for any namespaces.
>
> Because that is what namespaces are about backwards compatibility.

Are you claiming that namespaces are soley about backwards
compatibility?  ie. to trick userland into scoping without letting it
notice?  That's a very restricted view and namespaces do provide
further isolation capabilties in addition to what can be achieved
otherwise and it is logical to collect simliar funtionalities there.

Thanks.

-- 
tejun