status/usage of multiboot2 in grub2 with Xen 4.9+?

[PGNet Dev]

I have grub2 installed on an Opensuse Xen 4.9 Dom0 host,

        grub2-2.02-3.1.x86_64
        grub2-i386-pc-2.02-3.1.x86_64
        grub2-x86_64-efi-2.02-3.1.x86_64
        grub2-x86_64-xen-2.02-3.1.x86_64
        kernel-default-4.11.0-4.1.gcb15206.x86_64
        xen-4.9.0_04-493.2.x86_64
        xen-libs-4.9.0_04-493.2.x86_64
        xen-tools-4.9.0_04-493.2.x86_64

reading @ https://wiki.xenproject.org/wiki/Xen_EFI, multiboot2 is supposedly 
supported

        ...
        Xen as gz binary
                ...
                Xen 4.9 and later implements both multiboot and multiboot2.
                ...

with instructions to

        Inspect the grub.cfg. Make sure that it has 'multiboot2' and 'module2' 
for Xen

Here,

        ls -al /boot/xen*gz
                -rw-r--r-- 1 root root 984K May 12 01:20 
/boot/xen-4.9.0_04-493.gz
                lrwxrwxrwx 1 root root   19 May 12 09:31 /boot/xen-4.9.gz -> 
xen-4.9.0_04-493.gz
                lrwxrwxrwx 1 root root   19 May 12 09:31 /boot/xen-4.gz -> 
xen-4.9.0_04-493.gz
                -rw-r--r-- 1 root root 984K May 12 01:18 
/boot/xen-dbg-4.9.0_04-493.gz
                lrwxrwxrwx 1 root root   23 May 12 09:31 /boot/xen-dbg-4.9.gz 
-> xen-dbg-4.9.0_04-493.gz
                lrwxrwxrwx 1 root root   23 May 12 09:31 /boot/xen-dbg-4.gz -> 
xen-dbg-4.9.0_04-493.gz
                lrwxrwxrwx 1 root root   23 May 12 09:31 /boot/xen-dbg.gz -> 
xen-dbg-4.9.0_04-493.gz
                lrwxrwxrwx 1 root root   19 May 12 09:32 /boot/xen.gz -> 
xen-4.9.0_04-493.gz


but, grub.cfg still appears to use the chainloader mech, with no mention of 
"multiboot2"

        cat /boot/grub2/grub.cfg
                ...
                ### BEGIN /etc/grub.d/20_linux_xen ###
                menuentry 'OpenSUSE, with Xen hypervisor' --class opensuse 
--class gnu-linux --class gnu --class os --class xen $menuentry_id_option 
'xen-gnulinux-simple-4716053b-39da-4cc1-a7ce-72171b862357' {
                        echo    'Loading Xen 4.9.0_04-493 with Linux 
4.11.0-4.gcb15206-default ...'
                        chainloader  $cmdpath/xen-4.9.0_04-493.efi 
xen-4.9.0_04-493.efi  /mapbs config.1
                }
                submenu 'Advanced options for OpenSUSE (with Xen hypervisor)' 
$menuentry_id_option 'gnulinux-advanced-4716053b-39da-4cc1-a7ce-72171b862357' {
                        submenu 'Xen hypervisor, version 4.9.0_04-493' 
$menuentry_id_option 
'xen-hypervisor-4.9.0_04-493-4716053b-39da-4cc1-a7ce-72171b862357' {
                                menuentry 'OpenSUSE, with Xen 4.9.0_04-493 and 
Linux 4.11.0-4.gcb15206-default' --class opensuse --class gnu-linux --class gnu 
--class os --class xen $menuentry_id_option 
'xen-gnulinux-4.11.0-4.gcb15206-default-advanced-4716053b-39da-4cc1-a7ce-72171b862357'
 {
                                        echo    'Loading Xen 4.9.0_04-493 with 
Linux 4.11.0-4.gcb15206-default ...'
                                        chainloader  
$cmdpath/xen-4.9.0_04-493.efi xen-4.9.0_04-493.efi  /mapbs config.2
                                }
                                menuentry 'OpenSUSE, with Xen 4.9.0_04-493 and 
Linux 4.11.0-3.g39615a9-default' --class opensuse --class gnu-linux --class gnu 
--class os --class xen $menuentry_id_option 
'xen-gnulinux-4.11.0-3.g39615a9-default-advanced-4716053b-39da-4cc1-a7ce-72171b862357'
 {
                                        echo    'Loading Xen 4.9.0_04-493 with 
Linux 4.11.0-3.g39615a9-default ...'
                                        chainloader  
$cmdpath/xen-4.9.0_04-493.efi xen-4.9.0_04-493.efi  /mapbs config.3
                                }
                        }
                }

                ### END /etc/grub.d/20_linux_xen ###
                ...

checking, the current grub appears to have multiboot2 modules installed

        ls -al {/usr/lib/grub2,/boot/grub2}/x86_64-efi/multiboot2*
                -rw-r--r-- 1 root root  25K May 12 08:52 
/boot/grub2/x86_64-efi/multiboot2.mod
                -rw-r--r-- 1 root root  25K May 12 00:21 
/usr/lib/grub2/x86_64-efi/multiboot2.mod
                -rw-r--r-- 1 root root 164K May 12 00:21 
/usr/lib/grub2/x86_64-efi/multiboot2.module

So it looks like the pieces are there ...

What needs be done to enable the multiboot2 usage?  Additional/different config 
on my part?   Or, is support -- either from the grub2 or Xen sides -- not yet 
fully implemented?