Am 07.05.24 um 13:19 schrieb marcandre.lur...@redhat.com:
> From: Marc-André Lureau <marcandre.lur...@redhat.com>
>
> Hi,
>
> The aforementioned patch breaks virtio-gpu device migrations for versions
> pre-9.0/9.0, both forwards and backwards. Versioning of `VMS_STRUCT` is more
> complex than it may initially appear, as evidenced in the problematic commit
> dfcf74fa68c ("virtio-gpu: fix scanout migration post-load").
>
> To resolve this, we need to propagate the `vmstate` `version_id` through the
> nested structures. Additionally, we should tie specific machine version to a
> corresponding `version_id` to maintain migration compatibility.
>
> `VMS_VSTRUCT` allows specifying the appropriate version of the nested
> structure
> to use.
>
> Marc-André Lureau (4):
> migration: add "exists" info to load-state-field trace
> include/migration: add VMSTATE_VSTRUCT_TEST_VARRAY_UINT32
> virtio-gpu: use a VMState variant for the scanout field
> virtio-gpu: add x-vmstate-version
>
> include/hw/virtio/virtio-gpu.h | 1 +
> include/migration/vmstate.h | 12 ++++++++++++
> hw/core/machine.c | 1 +
> hw/display/virtio-gpu.c | 28 +++++++++++++++++++++-------
> migration/vmstate.c | 5 +++--
> migration/trace-events | 2 +-
> 6 files changed, 39 insertions(+), 10 deletions(-)
>
Tested-by: Fiona Ebner <f.eb...@proxmox.com>
Thank you for the fix! Tested with an Ubuntu 23.10 VM:
Machine type pc-i440fx-8.2:
1. create snapshot with 8.2, load with patched 9.0
2. create snapshot with patched 9.0, load with patched 9.0 and with 8.2
Machine type pc-i440fx-9.0:
1. create snapshot with patched 9.0, load with patched 9.0
No crashes/failures and didn't notice any other issues :)
Best Regards,
Fiona
