From: Johannes Weiner <hannes@cmpxchg.org>
Date: Sat, 23 Feb 2013 00:35:20 +0000 (-0800)
Subject: mm/mlock.c: document scary-looking stack expansion mlock chain
X-Git-Tag: v3.9-rc1~99^2~38
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4805b02e90187c68d8f4e3305c3482b797e35809;p=pandora-kernel.git

mm/mlock.c: document scary-looking stack expansion mlock chain

The fact that mlock calls get_user_pages, and get_user_pages might call
mlock when expanding a stack looks like a potential recursion.

However, mlock makes sure the requested range is already contained
within a vma, so no stack expansion will actually happen from mlock.

Should this ever change: the stack expansion mlocks only the newly
expanded range and so will not result in recursive expansion.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Hugh Dickins <hughd@google.com>
Acked-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

Reading git-diff-tree failed