$ git clone -n https://gitee.com/uestc-cheng/libxml2.git /var/lib/mock/dist-an8.8-build-299469-65890/root/chroot_tmpdir/scmroot/libxml2
Cloning into '/var/lib/mock/dist-an8.8-build-299469-65890/root/chroot_tmpdir/scmroot/libxml2'...
$ git fetch origin 0fa170af01e3643432ea39de85ea31b9af5fe23c:KOJI_FETCH_HEAD
From https://gitee.com/uestc-cheng/libxml2
 * [new ref]         0fa170af01e3643432ea39de85ea31b9af5fe23c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0fa170a update libxml2.spec.