From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: what's parisc execve_wrapper doing in the end?
Date: Fri, 5 Oct 2012 20:21:33 +0100
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Cc: Parisc List <linux-parisc@vger.kernel.org>
To: James Bottomley <James.Bottomley@HansenPartnership.com>
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On Fri, Oct 05, 2012 at 03:55:36PM +0100, James Bottomley wrote:

> But there's not a lot of point.  forking an idle thread actually doesn't
> care about any of the register execution setup because it never really
> uses it to execute.  That's why it was safe for us to use the user
> thread setup ... I suppose the interior of the kernel thread case could
> be conditioned on if (usp).

FWIW, I'm digging through the fork_idle() interplay with copy_thread()
right now and the more I'm looking the less I like having called
copy_thread() at all on that path.  Note that copy_process() can trivially
tell it from the normal (do_fork()) caller, just by checking if pid
is non-NULL.  And it has to check that anyway when it decides to generate
the pid for child...

Hell knows; I wonder how much of copy_thread() work is needed in that case...