1 files changed, 16 insertions, 2 deletions

diff --git a/mm/compaction.c b/mm/compaction.c
index ec74cf0123ef..f9792ba3537c 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -479,6 +479,16 @@ isolate_freepages_range(struct compact_control *cc,
 
                 block_end_pfn = min(block_end_pfn, end_pfn);
 
+                /*
+                 * pfn could pass the block_end_pfn if isolated freepage
+                 * is more than pageblock order. In this case, we adjust
+                 * scanning range to right one.
+                 */
+                if (pfn >= block_end_pfn) {
+                        block_end_pfn = ALIGN(pfn + 1, pageblock_nr_pages);
+                        block_end_pfn = min(block_end_pfn, end_pfn);
+                }
+
                 if (!pageblock_pfn_to_page(pfn, block_end_pfn, cc->zone))
                         break;
 
@@ -1029,8 +1039,12 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
         }
 
         acct_isolated(zone, cc);
-        /* Record where migration scanner will be restarted */
-        cc->migrate_pfn = low_pfn;
+        /*
+         * Record where migration scanner will be restarted. If we end up in
+         * the same pageblock as the free scanner, make the scanners fully
+         * meet so that compact_finished() terminates compaction.
+         */
+        cc->migrate_pfn = (end_pfn <= cc->free_pfn) ? low_pfn : cc->free_pfn;
 
         return cc->nr_migratepages ? ISOLATE_SUCCESS : ISOLATE_NONE;
 }