On Mon, Mar 21, 2011 at 3:40 PM, John Lindgren [off-list ref] wrote:

Hi,

I want to report a bug in the Linux kernel 2.6.38.  Loading the radeon
module causes the console to go completely blank (laptop backlight on, but
nothing displayed).  The system still responds to ctrl-alt-del and reboots.
 This is a regression from the previous kernel, 2.6.37.4, where kernel mode
setting works flawlessly.

With radeon.modeset=0, or with the module blacklisted, the system boots
fine, and I can use X, but without the powersaving features available
through KMS.

Please post to dri-devel list, but my first guess is missing fbcon or
something like that.

can't tell without complete dmesg.

Alternative file a bug on kernel bugzilla, with the complete dmesg attached.

Dave.