$ git clone -n https://src.fedoraproject.org/rpms/qemu.git /var/lib/mock/f41-build-side-1-2674975-29291/root/chroot_tmpdir/scmroot/qemu
Cloning into '/var/lib/mock/f41-build-side-1-2674975-29291/root/chroot_tmpdir/scmroot/qemu'...
$ git fetch origin 85461760741078b8bdb0d1f3e0d0738c7094a36e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/qemu
 * [new ref]         85461760741078b8bdb0d1f3e0d0738c7094a36e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8546176 Replace qemu --blacklist option with -b (related: RHBZ#2258100)