Re: [PATCH] Add a choosepid() syscall as a simpler alternative to clone_with_pids()

["Serge E. Hallyn" <serue-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>]

Quoting Oren Laadan (orenl-RdfvBDnrOixBDgjK7y7TUQ@public.gmane.org):
> Hi Dan,
> 
> Two comments:
> 
> 1. We already tried a similar approach over a year ago - selecting pids
> using a /proc interface instead of a dedicated syscall - and received
> chilling reactions. (IIRC posted by Nadia Derbey).

The chilling reactions were due to (1) general objections to the functionality
of clone_with_pids() itself, (2) new procfiles, the way alloc_pid() was being
extended (i.e. that was solved by Suka as well as (1)) and especially (3) using
a generic, multiplexed 'next_id' file.

I don't think we can extrapolate from those objections to this patchset
being objectionable.

> 2. What do you expect to gain by splitting the work into two separate
> system calls ?

Two very simple syscalls which are both trivially correct and trivial
for userspace to use.

-serge