$ git clone -n https://github.com/xcp-ng-rpms/qemu /var/lib/mock/v8.3-u-tae1-9149-27960/root/chroot_tmpdir/scmroot/qemu
Cloning into '/var/lib/mock/v8.3-u-tae1-9149-27960/root/chroot_tmpdir/scmroot/qemu'...
$ git fetch origin eec6a4fb0b075d1a3fc3672c793c5fe80ddfa3e2:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/qemu
 * [new ref]         eec6a4fb0b075d1a3fc3672c793c5fe80ddfa3e2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at eec6a4f bump release for test build