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Date: Thu, 18 Feb 2016 10:46:52 +0100
From: David Hildenbrand <dahi@linux.vnet.ibm.com>
Message-ID: <20160218104652.3cfd35ad@thinkpad-w530>
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Subject: Re: [Qemu-devel] [PATCH v4 5/5] s390x/cpu: Allow hotplug of CPUs
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To: Igor Mammedov <imammedo@redhat.com>
Cc: Matthew Rosato <mjrosato@linux.vnet.ibm.com>, qemu-devel@nongnu.org, agraf@suse.de, borntraeger@de.ibm.com, bharata@linux.vnet.ibm.com, cornelia.huck@de.ibm.com, pbonzini@redhat.com, afaerber@suse.de, rth@twiddle.net


> >  #if !defined(CONFIG_USER_ONLY)
> > +void s390_hot_add_cpu(const int64_t id, Error **errp)
> > +{  
> to make it future-proof wrt migration it could be better to
> enforce here that 'id' grows in +1 steps so user
> won't be able create cpus with gaps.

That should be already covered by:

if (id != next_cpu_id)
...

or am I missing something?

David