Radeon 9550 + R300 DRM + Xorg 6.9 = freeze

Not my lucky day :)

After upgrading my Xorg port to 6.9.0, my -CURRENT freezes at launch of kdm. 
I'm able to do nothing with the system (can't exit to debugger, can't ssh to 
it).  Running top in another tty while loading X at the same time shows that 
Xorg uses 99.9% of WCPU.  

Checking around, I found that the actual freeze was due to Xorg using the R300 
microcode (commenting out the Load "glx" and Load "dri" in xorg.conf makes X 
work again).  

I'm lost as to where to start debugging this as I cannot ssh, 
Ctrl-Alt-Backspace or get a dump during that freeze. Since it causes a crash, 
anything logged on the harddrive is lost (no sync done...)

I tried running xorgcfg (graphic mode) to see if it would record something 
useful in Xorg.8.log and I have it attached. For some reason, X detects my 
lcd as having a max res of 1280x1024, but tries to open a display for 
1600x1200 which only makes my screen show an "Out of Resolution" message. My 
console shows a message similar to "R300 Microcode loaded". I can 
Ctrl-Alt-Backspace out of X.

I've tried both dri and dri-devel with no luck.

So I resume:
  1. Xorg 6.9.0 + R300 DRM + dri causes freeze
  2. Disable dri+glx in Xorg.conf makes X work again (without drm)
  3. xorgcfg tries to start in 1600x1200 for a screen capable of only 
1280x1024, rendering it useless.

Anyone using a R300 powered card (Radeon 9550/9600) with DRM+Xorg 6.9.0 out 
there?

dmesg:
vgapci0: <VGA-compatible display> port 0xe000-0xe0ff mem 
0xe8000000-0xefffffff,0xfbe00000-0xfbe0ffff irq 16 at device 0.0 on pci1
drm0: <ATI Radeon AS 9600 AS> on vgapci0
info: [drm] AGP at 0xe0000000 64MB
info: [drm] Initialized radeon 1.19.0 20050911
vgapci1: <VGA-compatible display> mem 
0xf0000000-0xf7ffffff,0xfbf00000-0xfbf0ffff at device 0.1 on pci1

Thanks,
Nicolas
-- 
FreeBSD 7.0-CURRENT #0: Sat Jan 21 11:33:22 EST 2006     
root_at_clk01a:/usr/obj/usr/src/sys/CLK01A 
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