Re: [PATCH v4 04/14] vfio-user: define vfio-user-server object

[Jag Raman]

> On Dec 16, 2021, at 4:58 AM, Stefan Hajnoczi <stefanha@redhat.com> wrote:
> 
> On Wed, Dec 15, 2021 at 10:35:28AM -0500, Jagannathan Raman wrote:
>> +static void vfu_object_set_socket(Object *obj, Visitor *v, const char *name,
>> +                                  void *opaque, Error **errp)
>> +{
>> +    VfuObject *o = VFU_OBJECT(obj);
>> +
>> +    qapi_free_SocketAddress(o->socket);
>> +
>> +    o->socket = NULL;
>> +
>> +    visit_type_SocketAddress(v, name, &o->socket, errp);
>> +
>> +    if (o->socket->type != SOCKET_ADDRESS_TYPE_UNIX) {
>> +        qapi_free_SocketAddress(o->socket);
>> +        o->socket = NULL;
>> +        error_setg(errp, "vfu: Unsupported socket type - %s",
>> +                   o->socket->u.q_unix.path);
>> +        return;
>> +    }
>> +
>> +    trace_vfu_prop("socket", o->socket->u.q_unix.path);
>> +}
>> +
>> +static void vfu_object_set_device(Object *obj, const char *str, Error 
>> **errp)
>> +{
>> +    VfuObject *o = VFU_OBJECT(obj);
>> +
>> +    g_free(o->device);
>> +
>> +    o->device = g_strdup(str);
>> +
>> +    trace_vfu_prop("device", str);
>> +}
> 
> It appears "socket" and "device" can be changed after the
> vfio-user server has started. In the best case it just means the
> properties contain values that do not reflect the actual socket/device
> currently in use, which is confusing.

I’m not sure about the scenario in which that would occur, but will add that 
check.

Thank you!
--
Jag

> 
> It's safer to refuse changing these properties once the vfio-user
> server has started.
> 
> Stefan