serial: Fix double migration data

After c9808d6028 we have both an object representing the serial-isa
device and a separate object representing the underlying common serial
uart.  Both of these have vmsd's associated with them and thus the
migration stream ends up with two copies of the migration data - the
serial-isa includes the vmstate of the core serial.   Besides
being wrong, it breaks backwards migration compatibility.

Fix this by removing the dc->vmsd from the core device, so it only
gets migrated by any parent devices including it.
Add a vmstate_serial_mm so that any device that uses serial_mm_init
rather than creating a device still gets migrated.
(That doesn't fix backwards migration for serial_mm_init users,
but does seem to work forwards for ppce500).

Fixes: c9808d6028 ('serial: realize the serial device')
Buglink: https://bugs.launchpad.net/qemu/+bug/1869426
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20200330164712.198282-1-dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Dr. David Alan Gilbert 2020-03-30 17:47:12 +01:00 committed by Paolo Bonzini
parent ddd31732a7
commit f602d047ac

View File

@ -1043,7 +1043,6 @@ static void serial_class_init(ObjectClass *klass, void* data)
dc->user_creatable = false;
dc->realize = serial_realize;
dc->unrealize = serial_unrealize;
dc->vmsd = &vmstate_serial;
device_class_set_props(dc, serial_properties);
}
@ -1113,6 +1112,16 @@ static void serial_mm_realize(DeviceState *dev, Error **errp)
sysbus_init_irq(SYS_BUS_DEVICE(smm), &smm->serial.irq);
}
static const VMStateDescription vmstate_serial_mm = {
.name = "serial",
.version_id = 3,
.minimum_version_id = 2,
.fields = (VMStateField[]) {
VMSTATE_STRUCT(serial, SerialMM, 0, vmstate_serial, SerialState),
VMSTATE_END_OF_LIST()
}
};
SerialMM *serial_mm_init(MemoryRegion *address_space,
hwaddr base, int regshift,
qemu_irq irq, int baudbase,
@ -1162,6 +1171,7 @@ static void serial_mm_class_init(ObjectClass *oc, void *data)
device_class_set_props(dc, serial_mm_properties);
dc->realize = serial_mm_realize;
dc->vmsd = &vmstate_serial_mm;
}
static const TypeInfo serial_mm_info = {