diff --git a/block/genhd.c b/block/genhd.c
index 817c67c9e45e..82bc52cad1c1 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -831,6 +831,7 @@ static void disk_seqf_stop(struct seq_file *seqf, void *v)
 	if (iter) {
 		class_dev_iter_exit(iter);
 		kfree(iter);
+		seqf->private = NULL;
 	}
 }