From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Wed, 01 Feb 2012 14:41:01 +0000
Subject: [patch] mm: compaction: make compact_control order signed
Message-Id: <20120201144101.GA5397@elgon.mountain>
List-Id: <kernel-janitors.vger.kernel.org>
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To: Andrew Morton <akpm@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>, Minchan Kim <minchan@kernel.org>, Rik van Riel <riel@redhat.com>, Andrea Arcangeli <aarcange@redhat.com>, linux-mm@kvack.org, kernel-janitors@vger.kernel.org

"order" is -1 when compacting via /proc/sys/vm/compact_memory.  Making
it unsigned causes a bug in __compact_pgdat() when we test:

	if (cc->order < 0 || !compaction_deferred(zone, cc->order))
		compact_zone(zone, cc);

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/mm/compaction.c b/mm/compaction.c
index 382831e..5f80a11 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -35,7 +35,7 @@ struct compact_control {
 	unsigned long migrate_pfn;	/* isolate_migratepages search base */
 	bool sync;			/* Synchronous migration */
 
-	unsigned int order;		/* order a direct compactor needs */
+	int order;			/* order a direct compactor needs */
 	int migratetype;		/* MOVABLE, RECLAIMABLE etc */
 	struct zone *zone;
 };