Re: cgroup namespaces - mount root

From: Tejun Heo
Date: Wed Mar 16 2016 - 17:47:07 EST


Hello, Serge.

On Fri, Mar 11, 2016 at 03:50:10PM -0600, Serge E. Hallyn wrote:
> 'mount root' field (field 3) in /proc/self/mountinfo will show the
> same thing, the result of awk -F: '/freezer/ { print $3 }' /proc/self/cgroup.

I see.

> I keep waffling between thinking this is a problem that needs to be
> solved, and thinking "don't do that". But docker at least seems to
> have a problem with it right now, because it uses that field as part
> of its calculation of paths to write to.

Yeah, given that both are used in pretty simliar context, I think
distinguishing them would be a good idea.

> So, do you think it would be worth adding a 'nsroot=' entry in the
> optional fields (next shared:) ? I would've just sent a patch, but

Yeah, I think so.

> it actually isn't quite as simple as it would seem to find a way to
> get the absolute path during mountinfo_read(), so I thought I'd ask
> before spending more time on it.

Thanks.

--
tejun