$ git clone -n https://gitee.com/src-opencloudos-rpms/grub2.git /var/lib/mock/dist-oc9-build-246719-83496/root/chroot_tmpdir/scmroot/grub2
Cloning into '/var/lib/mock/dist-oc9-build-246719-83496/root/chroot_tmpdir/scmroot/grub2'...
$ git fetch origin c50f6841ad76f46565eb3dd8988eaeac1b7e7787:KOJI_FETCH_HEAD
From https://gitee.com/src-opencloudos-rpms/grub2
 * [new ref]         c50f6841ad76f46565eb3dd8988eaeac1b7e7787 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c50f684 import grub2-2.12-20.tl4.ap.3