diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index defb1cd8d2e1..18a72da759a0 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -1082,6 +1082,9 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway)
 	if (ubi->bgt_thread)
 		kthread_stop(ubi->bgt_thread);
 
+#ifdef CONFIG_MTD_UBI_FASTMAP
+	cancel_work_sync(&ubi->fm_work);
+#endif
 	ubi_debugfs_exit_dev(ubi);
 	uif_close(ubi);
 
diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index 668b46202507..23a6986d512b 100644
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -1505,6 +1505,7 @@ int ubi_thread(void *u)
 	}
 
 	dbg_wl("background thread \"%s\" is killed", ubi->bgt_name);
+	ubi->thread_enabled = 0;
 	return 0;
 }
 
@@ -1514,9 +1515,6 @@ int ubi_thread(void *u)
  */
 static void shutdown_work(struct ubi_device *ubi)
 {
-#ifdef CONFIG_MTD_UBI_FASTMAP
-	flush_work(&ubi->fm_work);
-#endif
 	while (!list_empty(&ubi->works)) {
 		struct ubi_work *wrk;