black screen when starting DRI

[Jacek P. <jac...@gm...>]

I have strange problem with DRI.
My hardware is ATI Radeon 9800PRO NH (AGP), Asus K8V-X SE and Athlon 64
3000+.

I use Arch Linux, I update my packages almost every day.
Few days ago i tried to update from xorg-server-1.1.1 to 1.2.0, but I
realized that X process uses 100% CPU all the time, so I submitted bug and
returned to 1.1.1.
In the last two days there was a new version of glibc, new version of kernel
2.6.20 and new gcc.

Yesterday after reboot I realized that I can't run X anymore. I see only
black screen after startx.
But system is not crashing, I can login via ssh and notice X taking almost
100% CPU.
I removed 'Load "dri"' from xorg.conf and it worked, so the problem is
DRI-related.

I tried to install older version of packages, I reinstalled xf86-video-ati,
libgl-dri, mesa, etc... But still have this problem.
I can't back to safe version of the system.
Currently I have no idea what to do, I will try with LiveCD or I will
temporarly install different version of distro.

But the point is, that it happened before. Suddenly I got black screen after
starting X.
And I started to analyze xorg.conf, chaning settings and I was able to make
it work.
Then I submitted this bug report:

https://bugs.freedesktop.org/show_bug.cgi?id=9232

I haven't wrote that in the report, but problem appeared without changing
xorg.conf!
Now I understand what does it mean. For some reason this value was enabled
by default!
Maybe now after I updated some packages something changed in the libraries
and now another DRI option is enabled by default?

Are default values safe?
Are they set intentionally or randomly (.i.e. not initialized at all)?

-- 
Free Software - find interesting programs and change them
NetHack - meet interesting creatures, kill them and eat their bodies
Usenet - meet interesting people from all over the world and flame them
Decopter - unrealistic helicopter simulator, get it from
http://decopter.sf.net