Re: [PATCH v1 02/27] xen/riscv: Implement construct_domain()

[Julien Grall <julien@xxxxxxx>]

Hi,

On 09/04/2026 22:39, Oleksii Kurochko wrote:
> > > > > +    BUG_ON(v->is_initialised);
> > > > > +
> > > > > +    kernel_load(kinfo);
> > > > > +    initrd_load(kinfo, copy_to_guest_phys);
> > > > > +    dtb_load(kinfo, copy_to_guest_phys);
> > > > These all return void, despite this also being used for non-Dom0. Is it
> > > > really fatal to a dom0less system if one out of many domains fail to be
> > > > built?
> > > For a dom0less system, my opinion is that it should not be fatal, it
> > > should simply ignore a domain that fails to build and continue with the
> > > rest. However, with the current common dom0less code it will just
> > > panic(). This is a behavior I would like to change and it is on my TODO
> > > list.
> > >
> > > Regarding the functions returning void, this is because all of them
> > > currently call panic() on failure, which I expect will need to change in
> > > order to ignore a domain that fails to build in dom0less mode.
> > >
> > > For the current implementation of the common dom0less code this is fine,
> > > but I agree it should be addressed in a separate patch series.
> > >
> > >    Especially when, despite the name, there is a Dom0?
> > >
> > > For this case, a failure there should indeed be fatal, so panic() is
> > > appropriate.
> > I think you misunderstood. I wasn't referring to the building of Dom0
> > failing. Was rather emphasizing that when there is a Dom0, failure to
> > create a DomU likely should even less so be fatal, as Dom0 could later
> > rectify the situation.
> Oh, okay, then it is really less fatal if DomU creation will fail in the 
> case of Dom0.
I am not sure I agree with this statement. The goal of dom0less is to 
not have a dom0 at all. So there is no way to rectify after the fact.
At least on Arm, we took the stance that boot failures are fatal because 
this is a clear signal that something went wrong. It may be more 
difficult to notice if you continue to boot.
Cheers,

--
Julien Grall