Somewhere between the debut of Ubuntu 9.10 (Karmic Koala for those into animal names) and today, the developers/maintainers/overlords of what many consider the leading Linux distribution have fixed the dreaded "kernel mode setting bug" that rendered the X Window system on many computers using Intel video hardware unusable until kernel mode setting was turned off.

I've been writing about such cockle-warming subjects as how Ubuntu 10.04 Lucid Lynx beta 2 and its 2.6.32 kernel handles such things as turning off kernel mode setting for Intel video that can't deal with said mode-setting, as well as the ever-moving buttons on application windows, and how the new gthumb is the best damn Linux/Unix photo-editing program for journalists.

Kernel mode setting hasn't been "fixed" for older Intel video, but at least the kernel knows not to turn it on when you're running an i915-type chipset (of which i810 is seemingly a subset). This is how things should have been handled from the beginning. Better late than never.

Kernel mode-setting for Intel graphics hardware can already be found in the mainline Linux kernel and will be included by default in the release of Ubuntu 9.10 later this year.

Kernel mode setting will be enabled by default for Intel-based video cards on Ubuntu 9.10, set to be released in October.  I recently played around with this new feature on a Karmic Koala live CD, and share my results below.

While the Intel stack may be improved in Constantine, the ATI support has taken a hit, as users were quick to point out in response to last week's article. In particular, when using the ATI kernel mode-setting driver in Fedora 12 (which is the default for pre-R600 hardware), there is a large performance discrepancy.

Just three days ago we shared that Nouveau will become the default NVIDIA driver in Fedora 11 to replace the obfuscated xf86-video-nv mess. Now proposed for Fedora 11 is to also integrate the Nouveau kernel mode-setting driver.

Last week we published benchmarks looking at the ATI Radeon KMS vs. UMS performance and found the user-space mode-setting support with the ATI driver to perform significantly faster than the newer kernel mode-setting routes in most instances. To see how the performance difference is on the Intel we ran a set of benchmarks on this side.

There was a talk last week at LinuxTag in Berlin by Egbert Eich about kernel mode-setting and the DRM (Direct Rendering Manager) graphics stack on Linux. Egbert is, of course, a long-time X developer and openSUSE developer at Novell who was one of the masterminds behind the RadeonHD graphics driver and has worked on various pieces of X over the years.