[vbox-dev] Windows 10 guest additions video driver problem

[Anna Fischer]

Am 25.02.2016 um 20:38 schrieb Frank Mehnert:
> Anna,
>
> On Thursday 25 February 2016 19:26:08 Anna Fischer wrote:
>>> Betreff: Re: [vbox-dev] Windows 10 guest additions video driver problem
>>>
>>> Hi,
>>>
>>> On Monday 04 January 2016 17:21:33 Anna Fischer wrote:
>>>>> Betreff: Re: [vbox-dev] Windows 10 guest additions video driver
>>>>>
>>>>> problem On Tuesday 29 December 2015 12:54:01 Anna Fischer wrote:
>>>>>> I run Virtualbox 5.0.10 on Gentoo Linux. I run different guest
>>>>>> operating systems, one of them Windows 10 64-bit. All my guests
>>>>>> have
>>>>>> 5.0.10 guest additions installed. All guests work fine except the
>>>>>> Windows 10 guest: when I suspend the system (e.g. the host OS goes
>>>>>> into hibernation / suspend to RAM mode) while the VM is running,
>>>>>> and then resume the system, it seems as if the guest graphics
>>>>>> driver crashes. Initially when the VM comes back on the screen
>>>>>> after resume, it seems as if the resolution is switched to a lower
>>>>>> resolution, and then I get a message in the guest saying video
>>>>>> driver crashed. Has anyone else ever seen this? I only seem to
>>>>>> have the problem with Windows 10 as guest. All other guests still
>>>>>> work after resume, and their
>>>>>
>>>>> resolution does not change.
>>>>>
>>>>> do you see the same problem if you suspend + resume the VM? I'm
>>>>> asking because basically this is the same what happens when you
>>>>> hibernate or suspend your host: All VMs are suspended before the
>>>>> host suspends and all VMs which were suspended before are resumed
>>>
>>> after the host resumed.
>>>
>>>> No, I don't see the same behavior, and I was expecting that it is a
>>>> different mechanism. Does VBOX actually detect that the host is trying
>>>> to hibernate, and then it will suspend all the VMs automatically? Is
>>>> that really how it works?
>>>
>>> yes, at least if dbus works as expected, see here:
>>>
>>> https://www.virtualbox.org/browser/vbox/trunk/src/VBox/Main/src-> > server/linux/HostPowerLinux.cpp#L134
>>>
>>> and here:
>>>
>>> https://www.virtualbox.org/browser/vbox/trunk/src/VBox/Main/src-> > server/HostPower.cpp#L74
>>>
>>> and later we will arrive Main/src/client/ConsoleImpl.cpp line 6195.
>>>
>>> The VBox.log file of running VMs should indicate if they are suspended/
>>> resumed on host suspend/resume.
>>
>> To me the code looks as if the VM is actually paused, not suspended (e.g.
>> saved). Is that so?
>
> Yes. VBox terminology:
>
> suspend(pause)/resume:
>    stop/continue the execution of the VM. The VM process remains.
>
> savestate:
>    save the VM state to disk and terminate the VM process
>
> restorestate:
>    start a new VM process and load the state from disk
>
>> It does not make sense to actually really suspend a VM (e.g. save state),
>> because for Windows 10 with 4-8 GB of RAM, this will take up to 30 seconds!
>
> Of course. Therefore we only pause/resume the VM in that case.

I can confirm now that when I manually pause the VM before host suspend, 
it does not break the guest. So the problem seems to be that for 
whatever reason, VirtualBox does not get to pause the VM before host 
suspend.

I have checked the logs, but I do not see any errors. Is there a way to 
increase logging of the VirtualBox service somehow? How can I debug this?

Cheers,
Anna