Re: [PATCH v2 33/35] x86/domain: implement domain_has_vuart()

[Denis Mukhin <dmkhn@xxxxxxxxx>]

On Monday, December 16th, 2024 at 7:11 AM, Jan Beulich <jbeulich@xxxxxxxx> 
wrote:

>
>
> On 06.12.2024 05:42, Denis Mukhin via B4 Relay wrote:
>
> > --- a/tools/libs/light/libxl_x86.c
> > +++ b/tools/libs/light/libxl_x86.c
> > @@ -8,7 +8,11 @@ int libxl__arch_domain_prepare_config(libxl__gc gc,
> > {
> > switch(d_config->c_info.type) {
> > case LIBXL_DOMAIN_TYPE_HVM:
> > - config->arch.emulation_flags = (XEN_X86_EMU_ALL & ~XEN_X86_EMU_VPCI);
> > + config->arch.emulation_flags = XEN_X86_EMU_ALL;
> > + config->arch.emulation_flags &= ~XEN_X86_EMU_VPCI;
> > + / Virtual UART is selected at Xen build time */
> > + config->arch.emulation_flags &= ~XEN_X86_EMU_VUART;
>
>
> That is all domains, even post-boot created ones, only ever get the same
> setting?

Toolstack cannot control vUART configuration yet. vUART can be enabled for
HVM domains only at this point and only globally, which seemed enough for the
initial implementation.
PVH needs some more work because PVH does not have vPIC.

I did not plan to enable per-domain configuration in this patch series (plan
to address in the follow on series). The emulator is disabled in default Xen
configuration, so it should not affect the existing default behavior.

>
> Jan