From a564da3964db3256069190c2ae95069143ac37fb Mon Sep 17 00:00:00 2001
From: Oleg Nesterov <oleg@tv-sign.ru>
Date: Wed, 22 Mar 2006 00:08:47 -0800
Subject: [PATCH] [PATCH] readahead: ->prev_page can overrun the ahead window

If get_next_ra_size() does not grow fast enough, ->prev_page can overrun
the ahead window.  This means the caller will read the pages from
->ahead_start + ->ahead_size to ->prev_page synchronously.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Steven Pratt <slpratt@austin.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
Reading git-format-patch failed