From: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Date: Thu, 22 May 2014 00:42:39 +0000 (+1000)
Subject: mm/pagewalk.c: fix end address calculation in walk_page_range()
X-Git-Tag: next-20140530~2^2~400
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=212ea39814ce0f5f796e7219ca18caa39fdf548e;p=karo-tx-linux.git

mm/pagewalk.c: fix end address calculation in walk_page_range()

When we try to walk over inside a vma, walk_page_range() tries to walk
until vma->vm_end even if a given end is before that point.
So this patch takes the smaller one as an end address.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/mm/pagewalk.c b/mm/pagewalk.c
index 4770558feea8..9f371ff67697 100644
--- a/mm/pagewalk.c
+++ b/mm/pagewalk.c
@@ -321,8 +321,9 @@ int walk_page_range(unsigned long start, unsigned long end,
 			next = vma->vm_start;
 		} else { /* inside the found vma */
 			walk->vma = vma;
-			next = vma->vm_end;
-			err = walk_page_test(start, end, walk);
+			next = min_t(unsigned long, end, vma->vm_end);
+
+			err = walk_page_test(start, next, walk);
 			if (skip_lower_level_walking(walk))
 				continue;
 			if (err)