From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH v5] cgroup: Add new capability to allow a process to
 migrate other tasks between cgroups
Date: Tue, 13 Dec 2016 13:40:57 -0500
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To: John Stultz <john.stultz-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Cc: Michael Kerrisk <mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, lkml <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>, Jonathan Corbet <corbet-T1hC0tSOHrs@public.gmane.org>, "open list:CONTROL GROUP (CGROUP)" <cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Android Kernel Team <kernel-team-z5hGa2qSFaRBDgjK7y7TUQ@public.gmane.org>, Rom Lemarchand <romlem-z5hGa2qSFaRBDgjK7y7TUQ@public.gmane.org>, Colin Cross <ccross-z5hGa2qSFaRBDgjK7y7TUQ@public.gmane.org>, Dmitry Shmidt <dimitrysh-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, Todd Kjos <tkjos-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, Christian Poetzsch <christian.potzsch-1AXoQHu6uovQT0dZR+AlfA@public.gmane.org>, Amit Pundir <amit.pundir-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, Dmitry Torokhov <dmitry.torokhov-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Kees Cook <keescook-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>, "Serge E . Hallyn" <serge-A9i7LUbDfNHQT0dZR+AlfA@public.gmane.org>, Andy Lutomirski <luto-kltTT9wpgjJwATOyAt5JVQ@public.gmane.org>, Linux API <linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
List-Id: linux-api@vger.kernel.org

Hello,

On Tue, Dec 13, 2016 at 08:08:16AM -0800, John Stultz wrote:
> On Tue, Dec 13, 2016 at 1:47 AM, Michael Kerrisk (man-pages)
> <mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> > On 13 December 2016 at 02:39, John Stultz <john.stultz-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> wrote:
> > So, back to the discussion of silos. I understand the argument for
> > wanting a new silo. But, in that case can we at least try not to make
> > it a single-use silo?
> >
> > How about CAP_CGROUP_CONTROL or some such, with the idea that this
> > might be a capability that allows the holder to step outside usual
> > cgroup rules? At the moment, that capability would allow only one such
> > step, but maybe there would be others in the future.
> 
> This sounds reasonable to me. Tejun/Andy: Objections?

Control group control?  The word control has a specific meaning for
cgroups and that second control doesn't make much sense to me.  Given
how this is mostly to patch up a hole in v1's delegation model and how
migration operations are different from others, I doubt that we will
end up overloading it.  Maybe just CAP_CGROUP?

Thanks.

-- 
tejun