linux-kernel - [PATCH] mm: vmscan: ensure reclaiming pages on the lru lists of zone

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:	Sun, 22 Jan 2012 11:08:20 +0800
From:	Hillf Danton <dhillf@...il.com>
To:	linux-mm@...ck.org
Cc:	Michal Hocko <mhocko@...e.cz>,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	Ying Han <yinghan@...gle.com>, Hugh Dickins <hughd@...gle.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Hillf Danton <dhillf@...il.com>
Subject: [PATCH] mm: vmscan: ensure reclaiming pages on the lru lists of zone

It is possible that the memcg input into shrink_mem_cgroup_zone() in
each round is not NULL, and the loop terminates at NULL case. And there
is chance that pages on the lru lists of zone are not reclaimed.

Mem cgroup iteration is refactored a bit to ensure the NULL case is also
input into the function.

Signed-off-by: Hillf Danton <dhillf@...il.com>
---

--- a/mm/vmscan.c	Sat Jan 14 14:02:20 2012
+++ b/mm/vmscan.c	Sun Jan 22 10:09:32 2012
@@ -2142,14 +2142,14 @@ static void shrink_zone(int priority, st
 		.zone = zone,
 		.priority = priority,
 	};
-	struct mem_cgroup *memcg;
+	struct mem_cgroup_zone mz = {
+		.zone = zone,
+	};
+	struct mem_cgroup *memcg = NULL;

-	memcg = mem_cgroup_iter(root, NULL, &reclaim);
 	do {
-		struct mem_cgroup_zone mz = {
-			.mem_cgroup = memcg,
-			.zone = zone,
-		};
+		memcg = mem_cgroup_iter(root, memcg, &reclaim);
+		mz.mem_cgroup = memcg,

 		shrink_mem_cgroup_zone(priority, &mz, sc);
 		/*
@@ -2166,7 +2166,6 @@ static void shrink_zone(int priority, st
 			mem_cgroup_iter_break(root, memcg);
 			break;
 		}
-		memcg = mem_cgroup_iter(root, memcg, &reclaim);
 	} while (memcg);
 }
--
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/