Re: [PATCH v2 1/2] target/ppc: Remove last user of .load_state_old

[Peter Maydell <peter.maydell@linaro.org>]

On Tue, 18 Jan 2022 at 11:18, Matheus K. Ferst
<matheus.ferst@eldorado.org.br> wrote:
>
> On 18/01/2022 07:41, Cédric Le Goater wrote:
> > This breaks migration compatibility from (very) old versions of
> > QEMU. This should not be a problem for the pseries machine for which
> > migration is only supported on recent QEMUs ( > 2.x). There is no
> > clear status on what is supported or not for the other machines. Let's
> > move forward and remove the .load_state_old handler.
> >
> > Signed-off-by: Cédric Le Goater <clg@kaod.org>
> > ---
> >   target/ppc/machine.c | 112 -------------------------------------------
> >   1 file changed, 112 deletions(-)
> >
> > diff --git a/target/ppc/machine.c b/target/ppc/machine.c
> > index 756d8de5d8dd..df547385ff1e 100644
> > --- a/target/ppc/machine.c
> > +++ b/target/ppc/machine.c
> > @@ -23,117 +23,6 @@ static void post_load_update_msr(CPUPPCState *env)
> >       pmu_update_summaries(env);
> >   }
> >
> > -static int cpu_load_old(QEMUFile *f, void *opaque, int version_id)
> > -{
> > -    PowerPCCPU *cpu = opaque;
>
> <snip>
>
> > -
> >   static int get_avr(QEMUFile *f, void *pv, size_t size,
> >                      const VMStateField *field)
> >   {
> > @@ -808,7 +697,6 @@ const VMStateDescription vmstate_ppc_cpu = {
> >       .version_id = 5,
> >       .minimum_version_id = 5,
> >       .minimum_version_id_old = 4,
> > -    .load_state_old = cpu_load_old,
>
> According to docs/devel/migration.rst, .minimum_version_id_old is
> ignored if no load_state_old handler is provided, I think we can drop it
> too.

Yes; the migration code only checks the field if load_state_old is non-NULL.

-- PMM