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Subject: Re: RFC [patch 13/34] PID Virtualization Define new task_pid api
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Hubertus Franke <frankeh@watson.ibm.com>,
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       Cedric Le Goater <clg@fr.ibm.com>
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Date: Mon, 23 Jan 2006 21:11:23 +0000
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On Llu, 2006-01-23 at 12:28 -0700, Eric W. Biederman wrote:
> > Yes, that's possible.. In the current patch that is not a problem, because
> > the internal pid (aka kpid) == <vpid,containerid>  mangeled together.
> > So in those cases, the kernel would have to keep <pid, container_id>
> 
> Agreed, and for the internal implementation I think having them mangled
> together make sense, so long as we never export that form to userspace.

You have to refcount the container ids anyway or you may have stale
container references and end up reusing them.