I want to add GRUB boot entries for Xen on Arch Linux using grub-mkconfig
My distribution does not package or install any linux kernel config file in /boot,
so 20_linux_xen does not function for me.

I work around this by or-testing to continue with zero length config file name in 20_linux_xen

http://git.savannah.gnu.org/cgit/grub.git/tree/util/grub.d/20_linux_xen.in#n169

-if (grep -qx "CONFIG_XEN_DOM0=y" "${config}" 2> /dev/null || grep -qx "CONFIG_XEN_PRIVILEGED_GUEST=y" "${config}" 2> /dev/null); then linux_list="$linux_list $i" ; fi
+if (grep -qx "CONFIG_XEN_DOM0=y" "${config}" 2> /dev/null || grep -qx "CONFIG_XEN_PRIVILEGED_GUEST=y" "${config}" 2> /dev/null || [ -z ${config} ]); then linux_list="$linux_list $i" ; fi

• If this would be appropriate for upstream, I can submit the patch?
• I do not know of any other simple way of checking for kernel xen support, such as parsing and testing the vmlinuz-linux file?
• https://stuff.mit.edu/afs/sipb/contrib/linux/scripts/extract-ikconfig does work to get a CONFIG for me, but I am guessing this parse vmlinuz functionality should not be a part of GRUB?

Otherwise, please let me know if this is more appropriate for distribution-level, where I could try to get implemented:

• This change in their shipped GRUB, or
• Install a dummy /boot/config-${version} with only CONFIG_XEN_DOM0=y as part of their Xen package

Cheers,
John