linux-kernel - [PATCH] memcg: fix mapcount check in move charge code for anonymous page

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Fri,  2 Mar 2012 15:35:08 -0500
From:	Naoya Horiguchi <n-horiguchi@...jp.nec.com>
To:	linux-mm@...ck.org
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Andrea Arcangeli <aarcange@...hat.com>,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	Daisuke Nishimura <nishimura@....nes.nec.co.jp>,
	Hillf Danton <dhillf@...il.com>, linux-kernel@...r.kernel.org,
	Naoya Horiguchi <n-horiguchi@...jp.nec.com>
Subject: [PATCH] memcg: fix mapcount check in move charge code for anonymous page

Currently charge on shared anonyous pages is supposed not to moved
in task migration. To implement this, we need to check that mapcount > 1,
instread of > 2. So this patch fixes it.

Signed-off-by: Naoya Horiguchi <n-horiguchi@...jp.nec.com>
---
 mm/memcontrol.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git linux-next-20120228.orig/mm/memcontrol.c linux-next-20120228/mm/memcontrol.c
index b6d1bab..785f6d3 100644
--- linux-next-20120228.orig/mm/memcontrol.c
+++ linux-next-20120228/mm/memcontrol.c
@@ -5102,7 +5102,7 @@ static struct page *mc_handle_present_pte(struct vm_area_struct *vma,
 		return NULL;
 	if (PageAnon(page)) {
 		/* we don't move shared anon */
-		if (!move_anon() || page_mapcount(page) > 2)
+		if (!move_anon() || page_mapcount(page) > 1)
 			return NULL;
 	} else if (!move_file())
 		/* we ignore mapcount for file pages */
-- 
1.7.7.6

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/