Re: VGA passthrough on unstable

[Liwei <xieliwei@gmail.com>]

>Date: Tue, 10 May 2011 13:55:04 -0400
>From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
>Subject: Re: [Xen-devel] Re: VGA passthrough on unstable
>To: JavMV <javiapple@hotmail.com>
>Cc: xen-devel@lists.xensource.com
>Message-ID: <20110510175504.GA15697@dumpdata.com>
>Content-Type: text/plain; charset=us-ascii
>
>> How can i fix this?
>> Is the patch hvmloader already applied in xen-unstable4.2?
>> Is there any difference between using pci-stub instead of pciback?
>
>Not for HVM guests.
>>
>> With these 2 patches applied I cannot run the virtual machine neither with
>> gfx_passthru = 0, but without those patches i was able to do it and was able
>> to see the Nvidia Card inside Windows but with error code43 and a yellow
>> exclamation symbol...
>
>Hmm, Does the error code show up anything on Google?

Whoops, I didn't notice there was a response to my post.

I did do a search but that is a pretty generic error Windows gives
when the driver decides something is wrong. No way of knowing
precisely what unless the driver spews some information somewhere
(which I think is unlikely).

However come to think of it, I did encounter that message twice
before. Once when I tested with PCI passthrough in ESXi and the other
time when the stock xen corrupted my card's firmware (I think, had to
reflash the backup firmware with nvflash for the card to work again).

So I guess in this case it may be due to the card being in an unknown
state when the driver is loaded? What if I made a change in xen to
execute card firmware even if gfx_passthrough = 0, without all the
modifications required for VGA passthrough? Though I suspect the
firmware expects some of the special VGA address mapping?