Re: [PATCH] failover: unregister ram on unplug

[Philippe Mathieu-Daudé]

On 7/21/21 12:49 PM, Laurent Vivier wrote:
> On 21/07/2021 12:41, Michael S. Tsirkin wrote:
>> On Wed, Jul 21, 2021 at 10:58:17AM +0200, Igor Mammedov wrote:
>>> On Tue, 20 Jul 2021 20:16:44 +0200
>>> Laurent Vivier <lvivier@redhat.com> wrote:
>>>
>>>> This simple change allows to test failover with a simulated device
>>>> like e1000e rather than a vfio device.
>>>>
>>>> This is interesting to developers that want to test failover on
>>>> a system with no vfio device. Moreover it simplifies host networking
>>>> configuration as we can use the same bridge for virtio-net and
>>>> the other failover networking device.
>>>>
>>>> Without this change the migration of a system configured with failover
>>>> fails with:
>>>>
>>>>   Unknown ramblock "0000:00:01.1:00.0/e1000e.rom", cannot accept migration
>>>>   error while loading state for instance 0x0 of device 'ram'
>>>>   load of migration failed: Invalid argument
>>>>
>>>> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
>>>
>>> Reviewed-by: Igor Mammedov <imammedo@redhat.com>
>>>
>>>> ---
>>>>  hw/net/virtio-net.c | 3 +++
>>>>  1 file changed, 3 insertions(+)
>>>>
>>>> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
>>>> index 16d20cdee52a..8f7735bad4f2 100644
>>>> --- a/hw/net/virtio-net.c
>>>> +++ b/hw/net/virtio-net.c
>>>> @@ -3256,6 +3256,9 @@ static void 
>>>> virtio_net_handle_migration_primary(VirtIONet *n, MigrationState *s)
>>>>      if (migration_in_setup(s) && !should_be_hidden) {
>>>>          if (failover_unplug_primary(n, dev)) {
>>>>              vmstate_unregister(VMSTATE_IF(dev), qdev_get_vmsd(dev), dev);
>>>> +            if (PCI_DEVICE(dev)->has_rom) {
>>
>>
>> Hmm. Any way to hide this behind an interface so
>> we don't need to poke at pci device internals?
> 
> There is the pci_del_option_rom() but it's not exported.
> 
> Do you want I export and use it?

Looks cleaner indeed.