$ git clone -n https://src.fedoraproject.org/rpms/ceph.git /var/lib/mock/f41-build-830888-156775/root/chroot_tmpdir/scmroot/ceph
Cloning into '/var/lib/mock/f41-build-830888-156775/root/chroot_tmpdir/scmroot/ceph'...
remote: warning: refname 'HEAD' is ambiguous.        
$ git reset --hard e75c15b5e1cb19133db3bd844b6d954a431ce9cf
HEAD is now at e75c15b possible fix for ppc64le build, see rhbz 2297744