Re: [RFC PATCH] spapr/xive: Allocate vCPU IPIs from local context

[Cédric Le Goater]

> > > Maybe it would be simpler to call xive_source_is_initialized() instead of
> > > xive_eas_is_valid() in cases like this, e.g. hcall code since it is shared
> > > between emulation and KVM ?
> >
> > Yes but we need a better check than :
> >
> >       if (lisn < SPAPR_XIRQ_BASE) {
> >           return !!xive_get_field64(EAS_END_INDEX, xive->eat[lisn].w);
> >       }
> >
> > This is more an heuristic than a precise test on the "validity" of
> > a source at the KVM level.
>
> I guess we should be able to get kvmppc_xive_irq_state::valid from
> KVM by making the KVM_DEV_XIVE_GRP_SOURCE attribute readable. Would
> that be enough ?

A bit slow may be. Or an extra bit in the XiveSource 'status' field
to reflect KVM initialization.

C.