Description of problem: I have installed both F12 and F13 (alpha) on my Lenovo X100e with an ATI RS780M/RS780MN video card. System hangs during boot, directly after switching to KMS . Removing quiet boot parameter shows up the following error message: Firmware Bug ACPI brightness control misses _BQC function. Setting radeon.modeset=0 solves the problem. Best Regards Marcus
I can confirm this bug on my X100e. As a side note the system boots every 10-15th time it try to boot with kms enabled. Using radeon.modeset=0 always boots fine, albeit this leeds to problems woth KDE if I enable desktop effects.
Improving summary. --- Fedora Bugzappers volunteer triage team https://fedoraproject.org/wiki/BugZappers [This triage is part of collective effort done by students of University of Rijeka Department of Informatics.]
Just as additional information, if I manage to boot with KMS enabled the message "[Firmware Bug] ACPI brightness control misses _BQC function" is also present, so it seems that at random times the system continues, though I have not a found a way to discern when this will happen. Furtheron I noticed that after a hang the display brightness is set to maximum, independent of its previous setting, so it seems to me that really this brightness detection/setting ist causing this hang
This one seems to work for me now (finally) in F14 with the following kernel version: [sebastian@bear ~]$ uname -r 2.6.35.9-64.fc14.i686 Closing. Feel free to reopen if it still affects others. :)