[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-users] VGA passthru troubleshooting


My experience with Windows is that you have to restart the physical system before passing the card to install drivers.

If you restart the system you may have to eject it from the system tray icon for safe device ejection.

When you pass the card to a DomU, the card is initialized.  However, Windows does not reset the card.  So after that DomU is shutdown the card remains initialized.

When a Windows 7 DomU boots if the card is already in an initialized state, and driver installation, removal, and 3D applications will fail.

I attached a diagram as a visual aid to depict what is happening.


On Sat, Jun 23, 2012 at 3:30 PM, Chris <kavefish@xxxxxxxxx> wrote:
Thanks for the suggestion. It's taking me down a weird path.

I attempted installation of the fglrx Linux driver, which failed
(while building the module for my domU kernel). At first I thought
perhaps it failed because an instance of X was running as the Nvidia
driver does, so I switched the Fedora VM to run level 3... and then my
monitor lit up... the one that the Fedora VM was supposed to control.
Never mind there's supposed to be no X11 in run level 3.

As far as I can tell there's no driver bound to the device. The
/sys/bus/pci/device/<BFD>/ directory contains no driver symlink. Also,
the lsmod listing doesn't include anything that's obviously a video
driver. So I'm guessing that's what happens when it's just pure
software rendering, but I don't really know.  In any case, it's
definitely not either of the radeon or fglrx drivers.

The configuration that produces the effect closest to what I was
aiming for has 'gfx_passthru=0', which allows me to watch boot via VNC
and then the secondary adapter takes over when gdm starts. However,  I
use 'gfx_passthru=1' then I get the same behaviour as before where the
guest starts without error, but appears to hang shortly after

The Win7 VM behaviour is unchanged: 'gfx_passthru=0' starts booting
until the ATI driver loads and bluescreens; 'gfx_passthru=1'  hangs
very early after power-on. The result is the same whether using the
latest official release driver or the latest beta driver.

Any other ideas greatly appreciated

Xen-users mailing list

Attachment: Diagrams.pdf
Description: Adobe PDF document

Xen-users mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.