linux-kernel - [PATCH 21/28] mm, vmscan: Update classzone_idx if buffer_heads_over

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

Message-Id: <1460457904-754-8-git-send-email-mgorman@techsingularity.net>
Date:	Tue, 12 Apr 2016 11:44:57 +0100
From:	Mel Gorman <mgorman@...hsingularity.net>
To:	Andrew Morton <akpm@...ux-foundation.org>,
	Linux-MM <linux-mm@...ck.org>
Cc:	Rik van Riel <riel@...riel.com>, Vlastimil Babka <vbabka@...e.cz>,
	Johannes Weiner <hannes@...xchg.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Mel Gorman <mgorman@...hsingularity.net>
Subject: [PATCH 21/28] mm, vmscan: Update classzone_idx if buffer_heads_over_limit

If buffer heads are over the limit then the direct reclaim gfp_mask
is promoted to __GFP_HIGHMEM so that lowmem is indirectly freed. With
node-based reclaim, it is also required that the classzone_idx be updated
or the pages will be skipped.

Signed-off-by: Mel Gorman <mgorman@...hsingularity.net>
---
 mm/vmscan.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index e2238ab6ae53..9f2376ad4ce3 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2573,8 +2573,10 @@ static bool shrink_zones(struct zonelist *zonelist, struct scan_control *sc,
 	 * highmem pages could be pinning lowmem pages storing buffer_heads
 	 */
 	orig_mask = sc->gfp_mask;
-	if (buffer_heads_over_limit)
+	if (buffer_heads_over_limit) {
 		sc->gfp_mask |= __GFP_HIGHMEM;
+		classzone_idx = gfp_zone(sc->gfp_mask);
+	}
 
 	for_each_zone_zonelist_nodemask(zone, z, zonelist,
 					classzone_idx, sc->nodemask) {
-- 
2.6.4