Btrfs: Fix BUG_ON for fs converted from extN

Tree blocks can live in data block groups in FS converted from extN.
So it's easy to trigger the BUG_ON.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 6c14101506e1..a46b64de8f02 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4360,7 +4360,8 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
 
         block_rsv = get_block_rsv(trans, root);
         cache = btrfs_lookup_block_group(root->fs_info, buf->start);
-        BUG_ON(block_rsv->space_info != cache->space_info);
+        if (block_rsv->space_info != cache->space_info)
+                goto out;
 
         if (btrfs_header_generation(buf) == trans->transid) {
                 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {