From: Cyrill Gorcunov <gorcunov@openvz.org>
Date: Thu, 22 May 2014 00:42:44 +0000 (+1000)
Subject: mm: softdirty: don't forget to save file map softdiry bit on unmap
X-Git-Tag: next-20140530~2^2~383
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=edab7a7e7be320fabec6ecbecee1d7b5ffdf926f;p=karo-tx-linux.git

mm: softdirty: don't forget to save file map softdiry bit on unmap

pte_file_mksoft_dirty operates with argument passed by a value and returns
modified result thus we need to assign @ptfile here, otherwise itis a no-op
which may lead to loss of the softdirty bit.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/mm/rmap.c b/mm/rmap.c
index 79f21809a9ec..1c08cbdf40de 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1355,7 +1355,7 @@ static int try_to_unmap_cluster(unsigned long cursor, unsigned int *mapcount,
 		if (page->index != linear_page_index(vma, address)) {
 			pte_t ptfile = pgoff_to_pte(page->index);
 			if (pte_soft_dirty(pteval))
-				pte_file_mksoft_dirty(ptfile);
+				ptfile = pte_file_mksoft_dirty(ptfile);
 			set_pte_at(mm, address, pte, ptfile);
 		}