From: Brice Goglin <Brice.Goglin@inria.fr>
Date: Tue, 9 Dec 2008 21:14:23 +0000 (-0800)
Subject: mm: no get_user/put_user while holding mmap_sem in do_pages_stat?
X-Git-Tag: v2.6.28-rc8~20
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=80bba1290ab5122c60cdb73332b26d288dc8aedd;p=pandora-kernel.git

mm: no get_user/put_user while holding mmap_sem in do_pages_stat?

Since commit 2f007e74bb85b9fc4eab28524052161703300f1a, do_pages_stat()
gets the page address from user-space and puts the corresponding status
back while holding the mmap_sem for read.  There is no need to hold
mmap_sem there while some page-faults may occur.

This patch adds a temporary address and status buffer so as to only
hold mmap_sem while working on these kernel buffers.  This is
implemented by extracting do_pages_stat_array() out of do_pages_stat().

Signed-off-by: Brice Goglin <Brice.Goglin@inria.fr>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

Reading git-diff-tree failed