On 11/23/2016 11:48 AM, Dawid Zamirski wrote:
> On Wed, 2016-11-23 at 11:33 -0500, Dawid Zamirski wrote:
>> On Wed, 2016-11-23 at 11:00 -0500, Dawid Zamirski wrote:
>>> On Wed, 2016-11-23 at 08:55 -0500, John Ferlan wrote:
>>>> [...]
>>>>> +
>>>>> +static vboxDriverPtr
>>>>> +vboxGetDriverConnection(void)
>>>>> +{
>>>>> + virMutexLock(&vbox_driver_lock);
>>>>> +
>>>>> + if (vbox_driver) {
>>>>> + virObjectRef(vbox_driver);
>>>>> + } else {
>>>>> + vbox_driver = vboxDriverObjNew();
>>>>> +
>>>>> + if (!vbox_driver) {
>>>>> + virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
>>>>> + _("Failed to create vbox driver
>>>>> object."));
>>>>> + return NULL;
>>>>> + }
>>>>> + }
>>>>> +
>>>>> + if (vboxSdkInitialize() < 0 || vboxExtractVersion() < 0) {
>>>>
>>>> In this path should vboxSdkUninitialize be called (since it
>>>> wouldn't
>>>> be
>>>> called in the destroy path)?
>>>
>>> If vboxSdkUnintialize fails, VBoxSVC is not started so it does not
>>> need
>>> to be unintialized - which is in line with the sample code included
>>> SDK
>>> where it returns with EXIT_FAILUE in main if pfnClientInifialize
>>> fails.
>>> However, if vboxExtractVersion fails (unlikely) we might want to
>>> call
>>> gVBoxAPI.UPFN.Unintialize(vbox_driver) directly (not via
>>> vboxSdkUninitialize as it checks connectionCount > 0 which on
>>> failure
>>> would be 0). I've just tested both cases with
>>> gVBoxAPI.UPFN.Unintialize
>>> in the failure path, and calling it does not do any harm in both
>>> cases,
>>> so I guess it would be a good idea to put it there.
>>>
>>
>> Actually, I was wrong in that it's safe to call
>> gVBoxAPI.UPFN.Unintialize when vboxSdkInitialize fails - I got
>> segfault
>> when attempting to connect twice in VBOX_RELEASE(data->vboxObject).
>> It's safe to do this though:
>>
>> if (vboxSdkInitialize() < 0) {
>> virObjectUnref(vbox_driver);
>> virMutexUnlock(&vbox_driver_lock);
>>
>> return NULL;
>> }
>>
>> if (vboxExtractVersion() < 0) {
>> gVBoxAPI.UPFN.Uninitialize(vbox_driver);
>> virObjectUnref(vbox_driver);
>> virMutexUnlock(&vbox_driver_lock);
>>
>> return NULL;
>> }
>>
>> i.e do not uninitalize on initialize failure, but do unintialize on
>> vboxExractVersion failure.
>>
>
> Sigh, it segfaults even in this case as well... :-( Calling
> VBOX_RELEASE(data->vboxObj) more than once will trigger a segfault on
> that call in both cases. The only way to address this would be to
> change _pfnUnitilize in src/vbox/vbox_tmpl.c to check:
>
> if (data->vboxObj)
> VBOX_RELEASE(data->vboxObj);
>
> if (data->vboxSession)
> VBOX_RELEASE(data->vboxSession);
>
> if (data->vboxClient)
> VBOX_RELEASE(data->vboxClient);
>
>
> only then it's safe to do this in src/vbox/vbox_common.c
>
> if (vboxSdkInitialize() < 0 || vboxExtractVersion() < 0) {
> gVBoxAPI.UPFN.Uninitialize(vbox_driver);
> virObjectUnref(vbox_driver);
> virMutexUnlock(&vbox_driver_lock);
>
> return NULL;
> }
>
> I can send v3 with those changes applied if needed.
Seems our responses crossed paths... Maybe it'd be best to send a v3...
A couple of other nits I noted were the 2nd-4th arguments to virClassNew
for vboxDriverOnceInit weren't placed under the "virClass" first
argument (off by a space or two)
Also the finger twister uninitialize was typed as unintialize in a
comment and in the commit message as unitialize
John
>
> Regards,
> Dawid
>
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