Re: [PATCH v4 1/8] xen/domain: introduce common emulation flags

[Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>]

On 8/5/25 2:54 AM, dmkhn@xxxxxxxxx wrote:

> + Cc: Oleskii
>
> On Mon, Aug 04, 2025 at 11:46:36AM +0200, Jan Beulich wrote:
> > On 31.07.2025 21:21, dmkhn@xxxxxxxxx wrote:
> > > --- a/xen/include/xen/sched.h
> > > +++ b/xen/include/xen/sched.h
> > > @@ -652,6 +652,8 @@ struct domain
> > >      unsigned int *llc_colors;
> > >  #endif
> > >
> > > +    uint32_t emulation_flags;
> > >         
> > Just one further remark: The field probably never should have been of this
> > type; unsigned int will do, and imo will want switching to while the field
> > is being moved. (Before giving an x86 ack, I want to convince myself though
> > that this is moving us in the right direction.)
> >       
> Hi Jan,
>
> I can definitely use different mechanism for virt ns16550: add a new field in
> xen_arch_domainconfig. That will also simplify some of the emulation_flags
> checks on x86 and will be more flexible wrt emulator configuration (e.g. I can
> allow passing I/O ports ranges).
>
> Hi Arm/RISC-V maintainers,
>
> Do you foresee any need in bubbling up emulation_flags to the common `struct
> domain`?
>     
At the moment, in RISC-V's downstream branches emulation_flags isn't used. And,
for now, I am not really sure that it's going to be used in the nearest future.

~ Oleksii