diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index ea45112a98be..24a04cd757d6 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3153,6 +3153,7 @@ retry_root_backup:
 	if (IS_ERR(fs_info->fs_root)) {
 		err = PTR_ERR(fs_info->fs_root);
 		btrfs_warn(fs_info, "failed to read fs tree: %d", err);
+		fs_info->fs_root = NULL;
 		goto fail_qgroup;
 	}