mm/memory_hotplug.c: fix return value of online_pages()

online_pages() is called from memory_block_action() when a user requests
to online a memory block via sysfs.  This function needs to return a
proper error value in case of error.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index cd2990f..ca1dd3a 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -914,19 +914,19 @@
 	if ((zone_idx(zone) > ZONE_NORMAL || online_type == ONLINE_MOVABLE) &&
 	    !can_online_high_movable(zone)) {
 		unlock_memory_hotplug();
-		return -1;
+		return -EINVAL;
 	}
 
 	if (online_type == ONLINE_KERNEL && zone_idx(zone) == ZONE_MOVABLE) {
 		if (move_pfn_range_left(zone - 1, zone, pfn, pfn + nr_pages)) {
 			unlock_memory_hotplug();
-			return -1;
+			return -EINVAL;
 		}
 	}
 	if (online_type == ONLINE_MOVABLE && zone_idx(zone) == ZONE_MOVABLE - 1) {
 		if (move_pfn_range_right(zone, zone + 1, pfn, pfn + nr_pages)) {
 			unlock_memory_hotplug();
-			return -1;
+			return -EINVAL;
 		}
 	}