Date: Wed, 13 Apr 2016 14:50:33 -0400
From: Tejun Heo <tj@kernel.org>
To: "Serge E. Hallyn" <serge@hallyn.com>
Cc: linux-api@vger.kernel.org, adityakali@google.com,
        Linux Containers <containers@lists.osdl.org>,
        "Eric W. Biederman" <ebiederm@xmission.com>, cgroups@vger.kernel.org,
        lkml <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH] cgroup namespaces: add a 'nsroot=' mountinfo field
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 <20160413184639.GA29483@mail.hallyn.com>
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Hello, Serge.

On Wed, Apr 13, 2016 at 01:46:39PM -0500, Serge E. Hallyn wrote:
> It's not a leak of any information we're trying to hide.  I realize
> something like 8 years have passed, but I still basically go by the
> ksummit guidance that containers are ok but the kernel's first priority
> is to facilitate containers but not trick containers into thinking
> they're not containerized.  So long as the container is properly set
> up, I don't think there's anything the workload could do with the
> nsroot= info other than *know* that it is in a ns cgroup.
> 
> If we did change that guidance, there's a slew of proc info that we
> could better virtualize :)

I see.  I'm just wondering because the information here seems a bit
gratuituous.  Isn't the only thing necessary telling whether the root
is bind mounted or namescoped?  Wouldn't simple "nsroot" work for that
purpose?

Thanks.

-- 
tejun