Re: [PATCH v4 2/2] KVM: move vcpu id checking to archs

From: Cornelia Huck
Date: Fri Apr 22 2016 - 06:22:25 EST


On Fri, 22 Apr 2016 11:25:38 +0200
Greg Kurz <gkurz@xxxxxxxxxxxxxxxxxx> wrote:

> On Thu, 21 Apr 2016 19:36:11 +0200
> Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx> wrote:

> > > For other architectures, it is simply KVM_MAX_VCPUS.
> >
> > (Other architectures would not implement the capability.)
> >
>
> So this would be KVM_CAP_PPC_MAX_VCPU_ID ?
>
> > >> I think this would also clarify the connection between VCPU limit and
> > >> VCPU_ID limit. Or is a boolean cap better?
> > >>
> > >
> > > Well, I'm not fan of adding a generic API to handle a corner case...
> >
> > I don't like it either, but I think that introducing the capability is
> > worth avoided problems.
> >
>
> I admit that having separate capabilities for the number of vcpus and the
> maximum vcpu id fixes the confusion once and for all.

Yes, and I think that the new max_vpcu_id cap should be generic for
that reason.