Re: [PATCH 2/2] x86: generalise vcpu0 creation for a domain

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Fri, 18 Jul 2025, Alejandro Vallejo wrote:
> Some arguments do want to be adjusted one way or the other spec_ctrl.c makes
> heavy assumptions about there not being any hwdom/ctldom separation, and both
> having domain_id == 0. There are other cases.
> 
> Yet another option is to single-out the Hyperlaunch/dom0less case and never
> apply dom0 commandline overrides there (dom0_*=). It'd be a flag in
> boot_domain. Might even allow us to compile them out altogether for
> dom0less-only configurations (e.g: CONFIG_DOM0LESS_BOOT && !CONFIG_DOM0_BOOT, 
> or
> something like that).
> 
> Thoughts?

I have been reviewing this in more detail, including the WIP draft that
Alejandro has not yet submitted to xen-devel, which completes the
hyperlaunch/dom0less enablement on x86. I think we should apply all
dom0 command line arguments exactly as they are to both classic Dom0 and
the hardware domain (and only to the hardware domain).

This is the simplest approach and the only one that would work with the
current code.