diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 56b758a..4aa313c 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -212,7 +212,7 @@ static void grow_zone_span(struct zone *zone, 
unsigned long start_pfn,
         zone_span_writelock(zone);

         old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
-       if (start_pfn < zone->zone_start_pfn)
+       if (!zone->spanned_pages || start_pfn < zone->zone_start_pfn)
                 zone->zone_start_pfn = start_pfn;