Re: [RFC PATCH 02/27] containers: Implement containers as kernel objects

From: James Bottomley
Date: Tue Feb 19 2019 - 22:46:11 EST


On Wed, 2019-02-20 at 11:04 +0800, Ian Kent wrote:
> On Tue, 2019-02-19 at 18:20 -0800, James Bottomley wrote:
> > On Tue, 2019-02-19 at 23:06 +0000, David Howells wrote:
> > > James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> wrote:
> > >
> > > > I thought we got agreement years ago that containers don't
> > > > exist in Linux as a single entity: they're currently a
> > > > collection of cgroups and namespaces some of which may and some
> > > > of which may not be local to the entity the orchestration
> > > > system thinks of as a "container".
> > >
> > > I wasn't party to that agreement and don't feel particularly
> > > bound by it.
> >
> > That's not at all relevant, is it? The point is we have widespread
> > uses of namespaces and cgroups that span containers today meaning
> > that a "container id" becomes a problematic concept. What we
> > finally got to with the audit people was an unmodifiable label
> > which the orchestration system can set ... can't you just use that?
>
> Sorry James, I fail to see how assigning an id to a collection of
> objects constitutes a problem or how that could restrict the way a
> container is used.

Rather than rehash the whole argument again, what's the reason you
can't use the audit label? It seems to do what you want in a way that
doesn't cause problems. If you can just use it there's little point
arguing over what is effectively a moot issue.

James


> Isn't the only problem here the current restrictions on the way
> objects need to be combined as a set and the ability to be able add
> or subtract from that set.
>
> Then again the notion of active vs. inactive might not be sufficient
> to allow for the needed flexibility ...
>
> Ian
>