Date: Wed, 16 Mar 2016 14:46:54 -0700
From: Tejun Heo <tj@kernel.org>
To: "Serge E. Hallyn" <serge@hallyn.com>
Cc: lkml <linux-kernel@vger.kernel.org>, cgroups@vger.kernel.org
Subject: Re: cgroup namespaces - mount root
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References: <20160311215010.GA5844@mail.hallyn.com>
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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