[Spice-devel] Windows QXL driver - low pixel depth, low resolution, laggard mouse

Damien Churchill damoxc at gmail.com
Wed Jun 15 13:35:57 PDT 2011

On 15 June 2011 21:11, --[ UxBoD ]-- <uxbod at splatnix.net> wrote:
> ----- Original Message -----
>> Hello, all.  We have recently jumped into SPICE with both hands and
>> feet
>> as we are intrigued with the possibilities.  But, we've hit a few
>> rocks
>> along the way!
>> The immediate problems with our two test Windows installations
>> (Windows7
>> and Windows Server 2008 running as KVM guests in Fedora 15) using the
>> QXL driver is that the pixel depth appears to be 4-bits, the only
>> available resolutions are 640x480 and 800x600, and the mouse is
>> unusably
>> lagged.
>> Here are the details.
>> Spice client compiled from
>> http://www.spice-space.org/download/releases/spice-0.8.1.tar.bz2 on
>> Debian Squeeze.
>> I believe the Windows QXL driver and vdagent were compiled from the
>> same.  Phil, could you please confirm that.
>> KVM is from Fedora 15 yum repositories.
>> Our first attempt on Windows 7 yielded a screen with appropriate
>> pixel
>> depth and quite responsive video however the mouse was nearly
>> unusable.
>> We checked the video driver and it appeared to be using VGA rather
>> than
>> QXL despite:
>>     'spicevmc'>
>>       'virtio' name='com.redhat.spice.0'/>
>>     'tablet' bus='usb'/>
>>     'mouse' bus='ps2'/>
>>     'spice' port='5800' tlsPort='5801' autoport='no'
>>     listen=''/>
>>       'qxl' vram='65536' heads='1'/>
>>       'pci' domain='0x0000' bus='0x00' slot='0x02'
>>       function='0x0'/>
>> This seemed to be due to the QXL driver being unsigned.  We next put
>> up
>> a Windows Server 2008 wondering if the mouse problem was a Windows 7
>> issue.  We were able to test sign the driver.  Anticipating splendid
>> success, we were deeply disappointed when we still had not only the
>> mouse problem but now saw the pixel depth and resolution problem.
>> We then test signed the QXL driver on Windows 7 and, lo and behold,
>> the
>> same pixel depth and resolution issues appeared now that we were
>> indeed
>> using the QXL driver.
>> What did we do wrong? We would dearly love for this to work and we
>> are
>> sure it must be working for someone if it is being used in
>> production.
>> Thanks - John
> John,
> Alon (Redhat Dev) has a patch for QEMU which should hopefully fix the 4bpp issue but the binary and necessary libraries he sent me would not run successfully on our server. It was execute and then hang and eventually time out. Perhaps, as discussed, we could build from source though I wonder why that patch has not been fully committed yet?
> --

Is the patch available to try anywhere? I'd like to give it a test and
see what happens.

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