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Date: Mon, 26 Feb 2018 11:35:03 +0100
From: Cornelia Huck <cohuck@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v1] numa: s390x has no NUMA
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To: David Hildenbrand <david@redhat.com>
Cc: qemu-s390x@nongnu.org, qemu-devel@nongnu.org, Eduardo Habkost <ehabkost@redhat.com>, Christian Borntraeger <borntraeger@de.ibm.com>

On Mon, 26 Feb 2018 11:28:26 +0100
David Hildenbrand <david@redhat.com> wrote:

> On 26.02.2018 11:19, Cornelia Huck wrote:
> > On Fri, 23 Feb 2018 18:36:57 +0100
> > David Hildenbrand <david@redhat.com> wrote:
> >   
> >> Right now it is possible to crash QEMU for s390x by providing e.g.
> >>     -numa node,nodeid=0,cpus=0-1
> >>
> >> Problem is, that numa.c uses mc->cpu_index_to_instance_props as an
> >> indicator whether NUMA is supported by a machine type. We don't
> >> implement NUMA on s390x (and that concept also doesn't really exist).
> >> We need mc->cpu_index_to_instance_props for query-cpus.  
> > 
> > Is existence of cpu_index_to_instance_probs the correct indicator for
> > numa, then?
> > 
> > OTOH, your patch is straightforward...  
> 
> Maybe it is get_default_cpu_node_id as Christian discovered?

Yes, that seems like a better candidate for checking.