$ git clone -n https://src.fedoraproject.org/rpms/libfabric.git /var/lib/mock/f40-build-2007266-45241/root/chroot_tmpdir/scmroot/libfabric
Cloning into '/var/lib/mock/f40-build-2007266-45241/root/chroot_tmpdir/scmroot/libfabric'...
$ git fetch origin dae1201bcebb5aa15822c5ff21581d6d93500d79:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libfabric
 * [new ref]         dae1201bcebb5aa15822c5ff21581d6d93500d79 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at dae1201 Upload source