$ git clone -n https://src.fedoraproject.org/rpms/xreader.git /var/lib/mock/f41-build-846703-163186/root/chroot_tmpdir/scmroot/xreader
Cloning into '/var/lib/mock/f41-build-846703-163186/root/chroot_tmpdir/scmroot/xreader'...
$ git fetch origin b017447d52e61eb2af9e171254f7705b1bec8167:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/xreader
 * [new ref]         b017447d52e61eb2af9e171254f7705b1bec8167 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b017447 Update to 4.2.2