Kernel panic with Xorg from git.

[Adam K Kirchhoff]

Hello all,

	I've been experimenting with Xorg from git in order to enjoy
some of the great new features available (particularly for r300 and
newer ATI cards). While it works great on my desktop machines, my
laptop completely locks up if I start Xorg from git (built this past
Sunday).  This includes updated drm, mesa, xserver, and xf86-video-ati
from git.  I'm trying to debug this as best I can, but I'm not quite
sure where to go from here.  It's a HP laptop, with a first generation
radeon mobility.  I've logged in from a serial console, and tailed the
Xorg log file after starting up the X server.  This is what I get from
the tail:


 Connector -- LVDS
 DAC Type  -- None
 TMDS Type -- None
 DDC Type  -- 0x1a0
(II) RADEON(0): Port2:
 Monitor   -- AUTO
 Connector -- STV
 DAC Type  -- TVDAC/ExtDAC
 TMDS Type -- None
 DDC Type  -- 0x0
(II) RADEON(0): I2C device "VGA-0:ddc2" registered at address 0xA0.
(II) RADEON(0): I2C device "VGA-0:ddc2" removed.
(II) RADEON(0): I2C device "VGA-0:ddc2" registered at address 0xA0.
(II) RADEON(0): I2C device "VGA-0:ddc2" removed.
(II) RADEON(0): I2C device "VGA-0:ddc2" registered at address 0xA0.
(II) RADEON(0): I2C device "VGA-0:ddc2" removed.
(II) RADEON(0): Output: VGA-0, Detected Monitor Type: 0
finished output detect: 0
(II) RADEON(0): I2C device "LVDS:ddc2" registered at address 0xA0.
(II) RADEON(0): I2C device "LVDS:ddc2" removed.
(II) RADEON(0): Output: LVDS, Detected Monitor Type: 0
(II) RADEON(0): Detected non-DDC Monitor Type: 2
finished output detect: 1
finished output detect: 2
finished all detect
before xf86InitialConfiguration
(II) RADEON(0): I2C device "VGA-0:ddc2" registered at address 0xA0.
(II) RADEON(0): I2C device "VGA-0:ddc2" removed.
(II) RADEON(0): I2C device "VGA-0:ddc2" registered at address 0xA0.
(II) RADEON(0): I2C device "VGA-0:ddc2" removed.
(II) RADEON(0): I2C device "VGA-0:ddc2" registered at address 0xA0.
(II) RADEON(0): I2C device "VGA-0:ddc2" removed.

And then (obviously not from the Xorg log file, but written to the
serial console by the kernel):

CPU 0: Machine Check Exception: 0000000000000007
Bank 3: b40000000000083b at 00000001fc0003c9
Kernel panic - not syncing: Unable to continue

My first thought was that this is an issue with the DRM, but even if I 
explicitly disable the dri module in my xorg.conf file, the lockup
still happens.

Any ideas on how to track this down further?

Adam