From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCHv3 8/8] cgroup: Add documentation for cgroup namespaces
Date: Wed, 11 Feb 2015 00:17:04 -0500
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To: "Eric W. Biederman" <ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
Cc: "Serge E. Hallyn" <serge-A9i7LUbDfNHQT0dZR+AlfA@public.gmane.org>, Richard Weinberger <richard-/L3Ra7n9ekc@public.gmane.org>, Linux API <linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Linux Containers <containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>, Serge Hallyn <serge.hallyn-GeWIH/nMZzLQT0dZR+AlfA@public.gmane.org>, "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Andy Lutomirski <luto-kltTT9wpgjJwATOyAt5JVQ@public.gmane.org>, cgroups mailinglist <cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Ingo Molnar <mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>

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