diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index 912d83d8860a984a938b604f3e2447c3e390ce89..b0b0f448e8434a08ccaf6fc4f75b9b23a2ad6c51 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -413,7 +413,7 @@ xfs_iomap_prealloc_size(
 		 * have a large file on a small filesystem and the above
 		 * lowspace thresholds are smaller than MAXEXTLEN.
 		 */
-		while (alloc_blocks >= freesp)
+		while (alloc_blocks && alloc_blocks >= freesp)
 			alloc_blocks >>= 4;
 	}