diff --git a/mm/page_owner.c b/mm/page_owner.c
index 65e24fb..3c99874 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -554,11 +554,17 @@
 				continue;
 
 			/*
-			 * We are safe to check buddy flag and order, because
-			 * this is init stage and only single thread runs.
+			 * To avoid having to grab zone->lock, be a little
+			 * careful when reading buddy page order. The only
+			 * danger is that we skip too much and potentially miss
+			 * some early allocated pages, which is better than
+			 * heavy lock contention.
 			 */
 			if (PageBuddy(page)) {
-				pfn += (1UL << page_order(page)) - 1;
+				unsigned long order = page_order_unsafe(page);
+
+				if (order > 0 && order < MAX_ORDER)
+					pfn += (1UL << order) - 1;
 				continue;
 			}
 
@@ -577,6 +583,7 @@
 			set_page_owner(page, 0, 0);
 			count++;
 		}
+		cond_resched();
 	}
 
 	pr_info("Node %d, zone %8s: page owner found early allocated %lu pages\n",
@@ -587,15 +594,12 @@
 {
 	struct zone *zone;
 	struct zone *node_zones = pgdat->node_zones;
-	unsigned long flags;
 
 	for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) {
 		if (!populated_zone(zone))
 			continue;
 
-		spin_lock_irqsave(&zone->lock, flags);
 		init_pages_in_zone(pgdat, zone);
-		spin_unlock_irqrestore(&zone->lock, flags);
 	}
 }