Re: [Qemu-devel] [PATCH v5 3/3] spapr: fix migration of ICPState objects from/to older QEMU

[David Gibson <david@gibson.dropbear.id.au>]

[-- Attachment #1: Type: text/plain, Size: 1322 bytes --]

On Wed, Jun 14, 2017 at 03:29:19PM +0200, Greg Kurz wrote:
> Commit 5bc8d26de20c ("spapr: allocate the ICPState object from under
> sPAPRCPUCore") moved ICPState objects from the machine to CPU cores.
> This is an improvement since we no longer allocate ICPState objects
> that will never be used. But it has the side-effect of breaking
> migration of older machine types from older QEMU versions.
> 
> This patch allows spapr to register dummy "icp/server" entries to vmstate.
> These entries use a dedicated VMStateDescription that can swallow and
> discard state of an incoming migration stream, and that don't send anything
> on outgoing migration.
> 
> As for real ICPState objects, the instance_id is the cpu_index of the
> corresponding vCPU, which happens to be equal to the generated instance_id
> of older machine types.
> 
> The machine can unregister/register these entries when CPUs are dynamically
> plugged/unplugged.
> 
> This is only available for pseries-2.9 and older machines, thanks to a
> compat property.
> 
> Signed-off-by: Greg Kurz <groug@kaod.org>

Applied to ppc-for-2.10.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 819 bytes --]