$ git clone -n https://github.com/xcp-ng-rpms/qemu /var/lib/mock/v8.3-u-tae1-9145-27960/root/chroot_tmpdir/scmroot/qemu
Cloning into '/var/lib/mock/v8.3-u-tae1-9145-27960/root/chroot_tmpdir/scmroot/qemu'...
$ git fetch origin e41914dc82576b03ee0e8fe160030007a4e9dba8:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/qemu
 * [new ref]         e41914dc82576b03ee0e8fe160030007a4e9dba8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e41914d Add virtio-vga support