Hi Michael
On Fri, May 10, 2024 at 2:26 PM Michael S. Tsirkin <m...@redhat.com> wrote:
>
> On Tue, May 07, 2024 at 03:19:19PM +0400, marcandre.lur...@redhat.com wrote:
> > From: Marc-André Lureau <marcandre.lur...@redhat.com>
> >
> > Depending on the version, use v1 or v2 of the scanout VM state.
> >
> > Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com>
> > ---
> > hw/display/virtio-gpu.c | 22 +++++++++++++++++-----
> > 1 file changed, 17 insertions(+), 5 deletions(-)
> >
> > diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c
> > index ae831b6b3e..4fd72caf3f 100644
> > --- a/hw/display/virtio-gpu.c
> > +++ b/hw/display/virtio-gpu.c
> > @@ -1191,17 +1191,29 @@ static const VMStateDescription
> > vmstate_virtio_gpu_scanout = {
> > },
> > };
> >
> > +static bool vmstate_before_v2(void *opaque, int version)
> > +{
> > + return version <= 1;
> > +}
> > +
> > static const VMStateDescription vmstate_virtio_gpu_scanouts = {
> > .name = "virtio-gpu-scanouts",
> > - .version_id = 1,
> > + .version_id = 2,
> > + .minimum_version_id = 1,
> > .fields = (const VMStateField[]) {
> > VMSTATE_INT32(parent_obj.enable, struct VirtIOGPU),
> > VMSTATE_UINT32_EQUAL(parent_obj.conf.max_outputs,
> > struct VirtIOGPU, NULL),
> > - VMSTATE_STRUCT_VARRAY_UINT32(parent_obj.scanout, struct VirtIOGPU,
> > - parent_obj.conf.max_outputs, 1,
> > - vmstate_virtio_gpu_scanout,
> > - struct virtio_gpu_scanout),
> > + VMSTATE_VSTRUCT_TEST_VARRAY_UINT32(parent_obj.scanout, struct
> > VirtIOGPU,
> > + vmstate_before_v2,
> > + parent_obj.conf.max_outputs, 1,
> > + vmstate_virtio_gpu_scanout,
> > + struct virtio_gpu_scanout, 1),
> > + VMSTATE_VSTRUCT_TEST_VARRAY_UINT32(parent_obj.scanout, struct
> > VirtIOGPU,
> > + NULL,
> > + parent_obj.conf.max_outputs, 2,
> > + vmstate_virtio_gpu_scanout,
> > + struct virtio_gpu_scanout, 2),
> > VMSTATE_END_OF_LIST()
> > },
>
>
> Just don't, please.
> Add a property and add a conditional field based on property, set
> from the compat machinery.
>
The version isn't propagated through the nested VMSDs, so
vmstate_virtio_gpu_scanout would only have v1, whether we have a field
test or not.
Can you be more explicit what alternative solution you propose?
thanks
--
Marc-André Lureau
