$ git clone -n https://src.fedoraproject.org/rpms/tvlsim.git /var/lib/mock/f42-build-3272987-41309/root/chroot_tmpdir/scmroot/tvlsim
Cloning into '/var/lib/mock/f42-build-3272987-41309/root/chroot_tmpdir/scmroot/tvlsim'...
$ git fetch origin 06c11d5694e21e7228c01dd3d8437e8f7e9d3b60:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/tvlsim
 * [new ref]         06c11d5694e21e7228c01dd3d8437e8f7e9d3b60 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 06c11d5 Upstream update