From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cornelia Huck <cornelia.huck@de.ibm.com>
Subject: Re: [PATCH v4 2/2] KVM: move vcpu id checking to archs
Date: Fri, 22 Apr 2016 12:22:10 +0200
Message-ID: <20160422122210.50450345.cornelia.huck@de.ibm.com>
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Cc: Radim =?UTF-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>,
	Paolo Bonzini <pbonzini@redhat.com>, james.hogan@imgtec.com,
	mingo@redhat.com, linux-mips@linux-mips.org, kvm@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	David Hildenbrand <dahi@linux.vnet.ibm.com>,
	qemu-ppc@nongnu.org, Paul Mackerras <paulus@samba.org>,
	David Gibson <david@gibson.dropbear.id.au>
To: Greg Kurz <gkurz@linux.vnet.ibm.com>
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On Fri, 22 Apr 2016 11:25:38 +0200
Greg Kurz <gkurz@linux.vnet.ibm.com> wrote:

> On Thu, 21 Apr 2016 19:36:11 +0200
> Radim Kr=C4=8Dm=C3=A1=C5=99 <rkrcmar@redhat.com> wrote:

> > > For other architectures, it is simply KVM_MAX_VCPUS. =20
> >=20
> > (Other architectures would not implement the capability.)
> >=20
>=20
> So this would be KVM_CAP_PPC_MAX_VCPU_ID ?
>=20
> > >> I think this would also clarify the connection between VCPU limi=
t and
> > >> VCPU_ID limit.  Or is a boolean cap better?
> > >>  =20
> > >=20
> > > Well, I'm not fan of adding a generic API to handle a corner case=
=2E.. =20
> >=20
> > I don't like it either, but I think that introducing the capability=
 is
> > worth avoided problems.
> >=20
>=20
> 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.