$ git clone -n https://github.com/fedora-riscv/mfem.git /var/lib/mock/f40-build-2665974-67104/root/chroot_tmpdir/scmroot/mfem
Cloning into '/var/lib/mock/f40-build-2665974-67104/root/chroot_tmpdir/scmroot/mfem'...
$ git fetch origin aeb6d14f7b91626253958562ebeed012f9e7b4b8:KOJI_FETCH_HEAD
From https://github.com/fedora-riscv/mfem
 * [new ref]         aeb6d14f7b91626253958562ebeed012f9e7b4b8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at aeb6d14 Add support for riscv64