From mboxrd@z Thu Jan  1 00:00:00 1970
From: Igor Mammedov <imammedo@redhat.com>
Subject: Re: should KVM or userspace be the one which decides what
 MIPIDR/affinity values to assign to vcpus?
Date: Wed, 10 Jun 2015 11:54:20 +0200
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To: Marc Zyngier <marc.zyngier@arm.com>
Cc: Shlomo Pongratz <shlomo.pongratz@huawei.com>, Shlomo Pongratz <shlomopongratz@gmail.com>, Pavel Fedin <p.fedin@samsung.com>, QEMU Developers <qemu-devel@nongnu.org>, Shannon Zhao <shannon.zhao@linaro.org>, Ashok Kumar <ashoks@broadcom.com>, "kvmarm@lists.cs.columbia.edu" <kvmarm@lists.cs.columbia.edu>
List-Id: kvmarm@lists.cs.columbia.edu

On Tue, 09 Jun 2015 15:35:21 +0100
Marc Zyngier <marc.zyngier@arm.com> wrote:

> On 09/06/15 15:01, Peter Maydell wrote:
> > On 9 June 2015 at 15:00, Marc Zyngier <marc.zyngier@arm.com> wrote:
> >>
> >> Yeah, what I had in mind was something along the lines of:
> >> - kernel computes its "default MPDIR"
> >> - kernel exposes a new capability "KVM_ARM_ALLOW_MPIDR_OVERRIDE" (or
> >> something along those lines)
> >> - userspace does the right thing.
> > 
> > You forgot the "???" step :-)
> 
> Indeed. I also missed the step that says "kernel is able to convert
> arbitrary MPIDR to vcpu_id in an efficient manner...". GICv3 is
> definitely going to require this.
x86 probably already has code that does this for APIC ID -> vcpu_id