diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index f22e00dfec6c4..96369c44863a1 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1455,7 +1455,8 @@ static int btrfs_init_fs_root(struct btrfs_root *root, dev_t anon_dev)
 		goto fail;
 
 	if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID &&
-	    !btrfs_is_data_reloc_root(root)) {
+	    !btrfs_is_data_reloc_root(root) &&
+	    is_fstree(root->root_key.objectid)) {
 		set_bit(BTRFS_ROOT_SHAREABLE, &root->state);
 		btrfs_check_and_init_root_item(&root->root_item);
 	}
diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c
index 43f905ab0a18d..2b39c7f9226fe 100644
--- a/fs/btrfs/tree-checker.c
+++ b/fs/btrfs/tree-checker.c
@@ -442,6 +442,20 @@ static int check_root_key(struct extent_buffer *leaf, struct btrfs_key *key,
 	btrfs_item_key_to_cpu(leaf, &item_key, slot);
 	is_root_item = (item_key.type == BTRFS_ROOT_ITEM_KEY);
 
+	/*
+	 * Bad rootid for reloc trees.
+	 *
+	 * Reloc trees are only for subvolume trees, other trees only need
+	 * to be COWed to be relocated.
+	 */
+	if (unlikely(is_root_item && key->objectid == BTRFS_TREE_RELOC_OBJECTID &&
+		     !is_fstree(key->offset))) {
+		generic_err(leaf, slot,
+		"invalid reloc tree for root %lld, root id is not a subvolume tree",
+			    key->offset);
+		return -EUCLEAN;
+	}
+
 	/* No such tree id */
 	if (unlikely(key->objectid == 0)) {
 		if (is_root_item)