diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 3ea3bbd..e5e0972 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -856,18 +856,15 @@
 	return bdi;
 }
 
-int bdi_register(struct backing_dev_info *bdi, struct device *parent,
-		const char *fmt, ...)
+int bdi_register_va(struct backing_dev_info *bdi, struct device *parent,
+		const char *fmt, va_list args)
 {
-	va_list args;
 	struct device *dev;
 
 	if (bdi->dev)	/* The driver needs to use separate queues per device */
 		return 0;
 
-	va_start(args, fmt);
 	dev = device_create_vargs(bdi_class, parent, MKDEV(0, 0), bdi, fmt, args);
-	va_end(args);
 	if (IS_ERR(dev))
 		return PTR_ERR(dev);
 
@@ -884,6 +881,19 @@
 	trace_writeback_bdi_register(bdi);
 	return 0;
 }
+EXPORT_SYMBOL(bdi_register_va);
+
+int bdi_register(struct backing_dev_info *bdi, struct device *parent,
+		const char *fmt, ...)
+{
+	va_list args;
+	int ret;
+
+	va_start(args, fmt);
+	ret = bdi_register_va(bdi, parent, fmt, args);
+	va_end(args);
+	return ret;
+}
 EXPORT_SYMBOL(bdi_register);
 
 int bdi_register_dev(struct backing_dev_info *bdi, dev_t dev)