[Bug 31527] DRI locks up the machine when starting X on a Radeon 9250

[ath]

Public bug reported:
https://launchpad.net/malone/bugs/31527

Affects: linux-meta linux-image-2.6-k7 (Ubuntu)
       Severity: Normal
       Priority: (none set)
         Status: Unconfirmed

Description:
I'm running Dapper with the latest upgrades (kernel 2.6.15-14-k7) using a Radeon 9250 256 MB on a VIA KT600 board.
Starting XOrg with the default configuration (the open source radeon + r200_dri driver) results in a complete lockup (no keyboard, no sysrq, I can't even ping the machine). Pretty hard to debug on my side...
It can worked around by disabling DRI in the X configuration (losing 3D acceleration, and probably even EXA).
Installing the latest R200 DRM (only the kernel module) from http://dri.freedesktop.org/snapshots/ fixes the issue.