From 4520d5b3104970a7b916bb0a92311e77fec9c3b6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?= <arve@android.com>
Date: Tue, 24 May 2011 17:12:24 -0700
Subject: [PATCH] --- yaml --- r: 250911 b: refs/heads/master c:
 6d3163ce86dd386b4f7bda80241d7fea2bc0bb1d h: refs/heads/master i:   250909:
 6b25d0a8e5c6c2ecb78590111895e6aee1906393   250907:
 44ebf0e6ef819103de324e13c3e052cc6b38b43e   250903:
 bab40a45e03a4b4832d0a98b2fff6f9ff52baeee   250895:
 3e161ab6c8cf88a49a0d418644c82d034bc3e8b9   250879:
 8f06f45f87f73e4995ebd5b68e21f11e9228bb60 v: v3

---
 [refs]                |  2 +-
 trunk/mm/page_alloc.c | 19 +++++++++++++++++--
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 152effe48aba..c8c91f3d3f4f 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 0091a47da0b720ca39511c7d90dcc768cafcaf58
+refs/heads/master: 6d3163ce86dd386b4f7bda80241d7fea2bc0bb1d
diff --git a/trunk/mm/page_alloc.c b/trunk/mm/page_alloc.c
index 44019da9632e..01e6b614839d 100644
--- a/trunk/mm/page_alloc.c
+++ b/trunk/mm/page_alloc.c
@@ -3328,6 +3328,20 @@ static inline unsigned long wait_table_bits(unsigned long size)
 
 #define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
 
+/*
+ * Check if a pageblock contains reserved pages
+ */
+static int pageblock_is_reserved(unsigned long start_pfn, unsigned long end_pfn)
+{
+	unsigned long pfn;
+
+	for (pfn = start_pfn; pfn < end_pfn; pfn++) {
+		if (!pfn_valid_within(pfn) || PageReserved(pfn_to_page(pfn)))
+			return 1;
+	}
+	return 0;
+}
+
 /*
  * Mark a number of pageblocks as MIGRATE_RESERVE. The number
  * of blocks reserved is based on min_wmark_pages(zone). The memory within
@@ -3337,7 +3351,7 @@ static inline unsigned long wait_table_bits(unsigned long size)
  */
 static void setup_zone_migrate_reserve(struct zone *zone)
 {
-	unsigned long start_pfn, pfn, end_pfn;
+	unsigned long start_pfn, pfn, end_pfn, block_end_pfn;
 	struct page *page;
 	unsigned long block_migratetype;
 	int reserve;
@@ -3367,7 +3381,8 @@ static void setup_zone_migrate_reserve(struct zone *zone)
 			continue;
 
 		/* Blocks with reserved pages will never free, skip them. */
-		if (PageReserved(page))
+		block_end_pfn = min(pfn + pageblock_nr_pages, end_pfn);
+		if (pageblock_is_reserved(pfn, block_end_pfn))
 			continue;
 
 		block_migratetype = get_pageblock_migratetype(page);