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Date: Wed, 9 Sep 2015 11:26:21 +0530
From: Bharata B Rao <bharata@linux.vnet.ibm.com>
Message-ID: <20150909055620.GE17433@in.ibm.com>
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Subject: Re: [Qemu-devel] [RFC PATCH v4 02/11] exec: Do vmstate
 unregistration from cpu_exec_exit()
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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, qemu-ppc@nongnu.org, tyreld@linux.vnet.ibm.com, nfont@linux.vnet.ibm.com, imammedo@redhat.com, afaerber@suse.de

On Fri, Sep 04, 2015 at 04:03:43PM +1000, David Gibson wrote:
> On Thu, Aug 06, 2015 at 10:57:08AM +0530, Bharata B Rao wrote:
> > cpu_exec_init() does vmstate_register and register_savevm for the CPU device.
> > These need to be undone from cpu_exec_exit(). These changes are needed to
> > support CPU hot removal and also to correctly fail hotplug attempts
> > beyond max_cpus.
> > 
> > Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
> 
> As with 1/2, looks reasonable, but I'm wondering how x86 hotplug is
> getting away without this.

x86 does this explicitly in CPU's unrealizefn. Since registration is
done from cpu_exec_init(), I though un-registration could be done
in cpu_exec_init() instead of each arch doing it separately.

As said earlier, I will probably pursue these changes separately from
this series.

Regards,
Bharata.