Help: problem with X11 / XFree86-DRI ; who to blame?

[Adam Jackson]

On Tue, 2008-01-08 at 23:29 -0800, Rob wrote:
> Hi,
> 
> My OS is an up-to-date version of Fedora 7 on a Intel based PC.
> 
> I use a particular academic/scientific video rendering software VMD
> ( http://www.ks.uiuc.edu/Research/vmd/ ).
> This software uses GLX/Mesa heavily.
> 
> My day-to-day window manager is XFCE. When I use VMD, it immediately
> freezes keyboard/mouse on my console as soon as any video rendering
> activity occurs. The typical error message in /var/log/messages is:
> 
>     kernel: [drm:i915_wait_irq] *ERROR* i915_wait_irq: EBUSY --
>                rec: 147447 emitted: 147473

That would be a bug in either the kernel driver for the 915, or in the
Mesa 3d driver.

> Eventually I solved the problem: I disabled XFree86-DRI in the file
> /etc/X11/xorg.conf.

If disabling DRI fixes it and you still perceive the software to be
usable, it must not be using GL that heavily...

- ajax