From mboxrd@z Thu Jan  1 00:00:00 1970
From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Mon, 09 May 2011 22:58:02 +0000
Subject: Re: [PATCH] Don't mlock guardpage if the stack is growing up
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To: Tony Luck <tony.luck@gmail.com>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>, Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>, Fenghua Yu <fenghua.yu@intel.com>, Hugh Dickins <hughd@google.com>, linux-kernel@vger.kernel.org, linux-parisc@vger.kernel.org, Michel Lespinasse <walken@google.com>, Oleg Nesterov <oleg@redhat.com>, linux-ia64@vger.kernel.org

On Mon, May 9, 2011 at 3:53 PM, Tony Luck <tony.luck@gmail.com> wrote:
>
> P.S. while we could start both stacks on the same page and have the grow
> away from the start point, ia64 actually starts them out a fair distance apart
> and lets them run into each other (if you have enough memory to let them
> grow that far, and if ulimit -s doesn't stop them earlier)

Ahh, so you never actually have one single mapping that has both flags set?

In that case, I won't even worry about it.

One thing I did want to verify: did the mlockall() actually change the
stack size without that patch? Just to double-check that the patch
actually did change semantics visibly.

                 Linus