Re: [Qemu-ppc] [PATCH 0/8] spapr: fix IOMMU and XICS/IRQs migration

[Paolo Bonzini]

Il 04/05/2014 15:56, Alexey Kardashevskiy ha scritto:
> On 03/14/2014 03:18 PM, Alexey Kardashevskiy wrote:
> > This initial problem came form libvirt - it does not preserve
> > the device order when running QEMU. So it is easy to get source QEMU with:
> > -device spapr-vscsi,id=scsi1,reg=0x2000 -device spapr-vscsi,id=scsi0,reg=0x3000
> > and destination QEMU with:
> > -device spapr-vscsi,id=scsi0,reg=0x3000 -device spapr-vscsi,id=scsi1,reg=0x2000
> >
> > Since SPAPR IOMMU device does not have a bus, it is identified in
> > the migration stream as "spapr-iommu" and @instance_id which is assigned
> > as IOMMUs are created. This results in broken migration as @reg does not match.
> > The first patch fixes this issue by adding a bus device and a bridge.
> >
> > However just 1/8 does not fix the migration as device creation order also
> > affects IRQs assigned to the devices, for both PCI and VIO.
> > 2/7..8/8 fix that by moving XICS IRQ management from SPAPR to XICS and
> > implementing migration support for the entire XICS IRQ map.
> >
> > As we are here, the patchset also prepares XICS to support multiple ICS
> > (interrupt servers).
> >
> > This is a bugfix patchset but it feels too big to go to 2.0, right? :)
>
>
> I understand that the first and last patches of the series are wrong but I
> would still like others to get in upstream. How to proceed now? Repost them
> all again? Thanks.

You are working around a libvirt problem caused by a missing QEMU feature.

At least patch 4 is probably unnecessary too.  2/3/5/6/7 (aka what's 
left) seem sane and likely to remain useful in order to implement the 
QEMU feature correctly.

Paolo