Re: [RFC PATCH] xen/kconfig: allow LATE_HWDOM config for ARM

["Daniel P. Smith" <dpsmith@xxxxxxxxxxxxxxxxxxxx>]

On 12/18/24 05:04, Sergiy Kibrik wrote:
> 18.12.24 03:17, Daniel P. Smith:
> > > On 17/12/2024 11:47, Sergiy Kibrik wrote:
> > > > Allow to build ARM configuration with support for initializing 
> > > > hardware domain.
> > > > On ARM it is only possible to start hardware domain in multiboot 
> > > > mode, so
> > > > dom0less support is required. This is reflected by dependency on 
> > > > DOM0LESS_BOOT
> > > > instead of directly depending on ARM config option.
> >
> > Just to make sure my assumption is correct, you are looking to do a 
> > multi-domain construction at boot time, with at least two domains. One 
> > of those two domains is the "control domain" and one is the "hardware 
> > domain", aka late hwdom except it's not constructed "late".
> yes, you're correct
>
> > If you want such a configuration, I would highly recommend you first 
> > enable setting flask labels via dom0less (assuming it is not there) 
> > before lighting this feature up. This is because the dummy/base policy 
> > has no support for differentiating between a "control domain" and a 
> > "hardware domain". What you really would end up with is two control 
> > domains, with one also having control over hardware.
> will check this out, thank you for suggestion!
Apologies, one minor correction. You would get a control domain and a 
domU with the hardware mapped into its address space, not two control 
domains. I was not thinking about the fact that dom0less builds a single 
dom0, if defined, and all the domain definitions are built as domU.
v/r,
dps