diff --git a/module/bdev/raid/bdev_raid.c b/module/bdev/raid/bdev_raid.c
index 9015aa0a2..8c037a7df 100644
--- a/module/bdev/raid/bdev_raid.c
+++ b/module/bdev/raid/bdev_raid.c
@@ -488,6 +488,13 @@ _raid_bdev_io_type_supported(struct raid_bdev *raid_bdev, enum spdk_bdev_io_type
 {
 	struct raid_base_bdev_info *base_info;
 
+	if (io_type == SPDK_BDEV_IO_TYPE_FLUSH ||
+	    io_type == SPDK_BDEV_IO_TYPE_UNMAP) {
+		if (raid_bdev->module->submit_null_payload_request == NULL) {
+			return false;
+		}
+	}
+
 	RAID_FOR_EACH_BASE_BDEV(raid_bdev, base_info) {
 		if (base_info->bdev == NULL) {
 			assert(false);
diff --git a/module/bdev/raid/bdev_raid.h b/module/bdev/raid/bdev_raid.h
index 125229947..0b5ee4bda 100644
--- a/module/bdev/raid/bdev_raid.h
+++ b/module/bdev/raid/bdev_raid.h
@@ -277,7 +277,7 @@ struct raid_bdev_module {
 	/* Handler for R/W requests */
 	void (*submit_rw_request)(struct raid_bdev_io *raid_io);
 
-	/* Handler for requests without payload (flush, unmap) */
+	/* Handler for requests without payload (flush, unmap). Optional. */
 	void (*submit_null_payload_request)(struct raid_bdev_io *raid_io);
 
 	TAILQ_ENTRY(raid_bdev_module) link;