$ git clone -n https://src.fedoraproject.org/rpms/ceph.git /var/lib/mock/f41-build-815633-149642/root/chroot_tmpdir/scmroot/ceph
Cloning into '/var/lib/mock/f41-build-815633-149642/root/chroot_tmpdir/scmroot/ceph'...
remote: warning: refname 'HEAD' is ambiguous.        
$ git fetch origin d43cb58ea8d4d3787ac0ef528abf426dfe25d448:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ceph
 * [new ref]         d43cb58ea8d4d3787ac0ef528abf426dfe25d448 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d43cb58 install libtacopie.so