$ git clone -n https://src.fedoraproject.org/rpms/libvirt.git /var/lib/mock/f40-build-2200240-51765/root/chroot_tmpdir/scmroot/libvirt
Cloning into '/var/lib/mock/f40-build-2200240-51765/root/chroot_tmpdir/scmroot/libvirt'...
$ git fetch origin 6eb56c2e715e7a764fe149f71449d04ab732e8b5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libvirt
 * [new ref]         6eb56c2e715e7a764fe149f71449d04ab732e8b5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6eb56c2 fix regression for default input bus in libvirt >= 9.3