* Greg Kurz (gr...@kaod.org) wrote:
> On Sun, 10 Sep 2017 15:37:33 +0100
> Mark Cave-Ayland <mark.cave-ayl...@ilande.co.uk> wrote:
>
> > Commit a90db15 "target-ppc: Convert ppc cpu savevm to VMStateDescription"
> > appears to drop the internal CPU IRQ state from the migration stream. Whilst
> > testing migration on g3beige/mac99 machines, test images would randomly
> > fail to
> > resume unless a key was pressed on the VGA console.
> >
> > Further investigation suggests that internal CPU IRQ state isn't being
> > preserved and so interrupts asserted at the time of migration are lost.
> > Adding
> > the pending_interrupts and irq_input_state fields back into the migration
> > stream appears to fix the problem here during local tests.
> >
> > As part of this commit we bump the vmstate_ppc version from 5 to 6 to handle
> > the additional fields.
> >
>
> And so this unconditionally breaks backward migration... what about adding
> a subsection for this ?
and wiring it to a flag on the machine type so that older machine types
don't send it.
Dave
> > Signed-off-by: Mark Cave-Ayland <mark.cave-ayl...@ilande.co.uk>
> > ---
> > target/ppc/machine.c | 6 +++++-
> > 1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/target/ppc/machine.c b/target/ppc/machine.c
> > index e59049f..8fec1a4 100644
> > --- a/target/ppc/machine.c
> > +++ b/target/ppc/machine.c
> > @@ -647,7 +647,7 @@ static const VMStateDescription vmstate_compat = {
> >
> > const VMStateDescription vmstate_ppc_cpu = {
> > .name = "cpu",
> > - .version_id = 5,
> > + .version_id = 6,
> > .minimum_version_id = 5,
> > .minimum_version_id_old = 4,
> > .load_state_old = cpu_load_old,
> > @@ -678,6 +678,10 @@ const VMStateDescription vmstate_ppc_cpu = {
> > VMSTATE_UINTTL(env.hflags_nmsr, PowerPCCPU),
> > /* FIXME: access_type? */
> >
> > + /* Interrupt state */
> > + VMSTATE_UINT32_V(env.pending_interrupts, PowerPCCPU, 6),
> > + VMSTATE_UINT32_V(env.irq_input_state, PowerPCCPU, 6),
> > +
> > /* Sanity checking */
> > VMSTATE_UINTTL_TEST(mig_msr_mask, PowerPCCPU,
> > cpu_pre_2_8_migration),
> > VMSTATE_UINT64_TEST(mig_insns_flags, PowerPCCPU,
> > cpu_pre_2_8_migration),
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
