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Date: Wed, 2 Dec 2015 08:34:20 +0530
From: Bharata B Rao <bharata@linux.vnet.ibm.com>
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Subject: Re: [Qemu-devel] [PATCH v5 01/10] vl: Don't allow CPU toplogies
 with partially filled cores
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To: David Gibson <david@gibson.dropbear.id.au>
Cc: mdroth@linux.vnet.ibm.com, aik@ozlabs.ru, agraf@suse.de, qemu-devel@nongnu.org, pbonzini@redhat.com, qemu-ppc@nongnu.org, tyreld@linux.vnet.ibm.com, nfont@linux.vnet.ibm.com, imammedo@redhat.com, afaerber@suse.de

On Tue, Dec 01, 2015 at 11:37:03AM +1100, David Gibson wrote:
> On Fri, Nov 20, 2015 at 06:24:30PM +0530, Bharata B Rao wrote:
> > Prevent guests from booting with CPU topologies that have partially
> > filled CPU cores or can result in partially filled CPU cores after
> > CPU hotplug like
> > 
> > -smp 15,sockets=1,cores=4,threads=4,maxcpus=16 or
> > -smp 15,sockets=1,cores=4,threads=4,maxcpus=17.
> > 
> > Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
> 
> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> 
> I may have missed a bit of the discussion leading up to this.  What
> was the rationale for still allowing partially filled sockets (and
> otherwise doing things at core rather than socket level?)

This is generic parsing code. I don't remember an explicit discussion
around allowing or dis-allowing paritialy filled sockets. I thought
disallowing partially filled cores from generic smp parsing code would
be an acceptable first step for all archs.

Regards,
Bharata.