$ git clone -n https://gitee.com/uestc-cheng/libxml2.git /var/lib/mock/dist-an8.8-build-299361-65890/root/chroot_tmpdir/scmroot/libxml2
Cloning into '/var/lib/mock/dist-an8.8-build-299361-65890/root/chroot_tmpdir/scmroot/libxml2'...
$ git reset --hard fa139acbaf7a72ce836ce984122be435d1deb8ad
HEAD is now at fa139ac update libxml2.spec.