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Subject: Re: RFC [patch 13/34] PID Virtualization Define new task_pid api
From: Arjan van de Ven <arjan@infradead.org>
To: "Eric W. Biederman" <ebiederm@xmission.com>
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> 
> A pointer to a task_struct while it kind of sort of works.  Is not
> a good solution.  The problem is that in a lot of cases we register
> a pid to get a signal or something similar and then we never unregister
> it.  So by using a pointer to a trask_struct you effectively hold the
> process in memory forever.

this is not right. Both the PID and the task struct have the exact same
lifetime rules, they HAVE to, to guard against pid reuse problems.