Re: [Qemu-devel] [PATCH v2] pc: drop external DSDT loading

[Michael S. Tsirkin]

On Mon, Aug 12, 2013 at 10:20:41AM -0500, Anthony Liguori wrote:
> "Michael S. Tsirkin" <address@hidden> writes:
> 
> > On Mon, Aug 12, 2013 at 09:01:44AM -0500, Anthony Liguori wrote:
> >> This breaks migration and is unneeded with modern SeaBIOS.
> >> 
> >> Signed-off-by: Anthony Liguori <address@hidden>
> >
> > Hmm don't we want to keep it around for machine types
> > 1.4.0 and 1.5.0?
> 
> Hrm, why?

Well this modifies the contents of ROM which
is loaded from FW CFG and isn't migrated, correct?
If guest is migrated from 1.6 to 1.5
while it is loading the ROM,
it will likely get a corrupted table.


> Regards,
> 
> Anthony Liguori
> 
> >
> > By the way, copy stable as well?
> > Loading it unconditonally is a cross
> > version migration bug that we probably want to fix
> > on stable branch - disabling for 1.3.0 and older.
> >
> >> ---
> >> v1 -> v2
> >>  - Still load external DSDT for q35
> >> ---
> >>  hw/i386/pc_piix.c | 1 -
> >>  1 file changed, 1 deletion(-)
> >> 
> >> diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
> >> index 95c45b8..311574a 100644
> >> --- a/hw/i386/pc_piix.c
> >> +++ b/hw/i386/pc_piix.c
> >> @@ -103,7 +103,6 @@ static void pc_init1(MemoryRegion *system_memory,
> >>                                OBJECT(icc_bridge), NULL);
> >>  
> >>      pc_cpus_init(cpu_model, icc_bridge);
> >> -    pc_acpi_init("acpi-dsdt.aml");
> >>  
> >>      if (kvm_enabled() && kvmclock_enabled) {
> >>          kvmclock_create();
> >> -- 
> >> 1.8.0