$ git clone -n https://src.fedoraproject.org/rpms/java-1.8.0-openjdk-portable.git /var/lib/mock/f38-build-side-42-init-devel-1014287-29465/root/chroot_tmpdir/scmroot/java-1.8.0-openjdk-portable
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1014287-29465/root/chroot_tmpdir/scmroot/java-1.8.0-openjdk-portable'...
$ git fetch origin 72b008f6ead293ee029aa54965f6553684622be1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/java-1.8.0-openjdk-portable
 * [new ref]         72b008f6ead293ee029aa54965f6553684622be1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 72b008f excluding ix86 arch