When dropping a empty tree, walk_down_tree() skips checking extent information for the tree root. This will triggers a BUG_ON in walk_up_proc(). Signed-off-by: Yan Zheng <zheng.yan@oracle.com> --- diff -urp 1/fs/btrfs/extent-tree.c 2/fs/btrfs/extent-tree.c --- 1/fs/btrfs/extent-tree.c 2010-01-22 12:16:34.203525744 +0800 +++ 2/fs/btrfs/extent-tree.c 2010-02-01 10:26:19.865562007 +0800 @@ -5402,10 +5402,6 @@ static noinline int walk_down_tree(struc int ret; while (level >= 0) { - if (path->slots[level] >- btrfs_header_nritems(path->nodes[level])) - break; - ret = walk_down_proc(trans, root, path, wc, lookup_info); if (ret > 0) break; @@ -5413,6 +5409,10 @@ static noinline int walk_down_tree(struc if (level == 0) break; + if (path->slots[level] >+ btrfs_header_nritems(path->nodes[level])) + break; + ret = do_walk_down(trans, root, path, wc, &lookup_info); if (ret > 0) { path->slots[level]++; -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html