Further research:

I disabled KMS using radeon.modeset=0 at the kernel cmdline. This leads to GNOME 3 Fallback mode. With this setup, the issue does not appear. Re-enabling KMS and forcing GNOME 3 Fallback mode shows the original issue.

+++ This bug was initially created as a clone of Bug #711215 +++

Created attachment 503321 [details]
Xorg.0.log

Description of problem:

I'm using a Thinkpad T60p with an ATI FireGL V5250 (RV530) with the radeon driver. The internal display (LVDS-0) is 1400x1050, the external display (DVI-0) is 1920x1200. If I disable the internal display, then after a VT switch or suspend/resume, the external display resolution is at 962x1200, and the internal display shows a screen, where the screen boundary seems to be in the middle of the display (see screenshots). After resetting the resolution in the System Config -> Display, the screen becomes readable again.


Version-Release number of selected component (if applicable):
kernel 2.6.38.7-30.fc15.x86_64 (only this package is from updates-testing)
xorg-x11-drv-ati-6.14.1-1.20110504gita6d2dba6.fc15.x86_64

How reproducible:
Every VT switch or suspend/resume

Steps to Reproduce:
1. Configure as above
2. Ctrl-Alt-F2, then Ctrl-Alt-F1 --> screen is garbled


Expected results:
Readable screen, resolution as before, internal screen turned of.

Additional info:

--- Additional comment from stefan on 2011-06-06 16:38:51 EDT ---

Created attachment 503322 [details]
dmesg with drm.debug=14

--- Additional comment from stefan on 2011-06-06 16:39:16 EDT ---

Created attachment 503323 [details]
Smolt Profile

--- Additional comment from stefan on 2011-06-06 16:40:12 EDT ---

Created attachment 503324 [details]
Screens (DVI-0 top, LVDS-0 bottom)