$ git clone -n https://src.fedoraproject.org/rpms/userspace-rcu.git /var/lib/mock/f42-build-864522-172396/root/chroot_tmpdir/scmroot/userspace-rcu
Cloning into '/var/lib/mock/f42-build-864522-172396/root/chroot_tmpdir/scmroot/userspace-rcu'...
$ git fetch origin ca810f1cd13230cacfcf66895a9aa0d42eca2bc3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/userspace-rcu
 * [new ref]         ca810f1cd13230cacfcf66895a9aa0d42eca2bc3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ca810f1 New upstream release 0.14.1