KMS support was new in 2.6.31, with 'stable' support for i915 based drivers, and unstable support for 2.6.32. 2.6.32 should bring Radeon 'stable' support. Nvidia support is expected to only be available via the Nouveau driver, which is currently not slated for inclusion currently.

We need to consider which of those technologies will be appropriate for Lucid.

Release Note



We want to provide the best user experience, and be able to use KMS for Radeon and NVidia machines.

User stories

Andy wants a pretty boot on his Radeon based machine. Simon wants suspend/resume to be reliable and fast.


Radeon KMS support is stable in time for release. Radeon mesa must be ready for KMS to be enabled.


Radeon KMS support should be available in 2.6.32 and later covering the kernel versions which Lucid is likely to have. To enable testing we should enable Radeon KMS by default as early as possible in the cycle. Interlock with X required.

Nouveau support is not likely to be in .32 or .33. We may wish to look at nouveau patches for Lucid, if they are independant enough they may be worth providing test images for the X-edgers team against the lucid kernel early in the cycle to allow stability and card support to be evaluated. We should be skeptical of enabling this for release by default.

Unresolved issues

  • Potential for Legal encomberance on the Nouveau patches needs legal review before inclusion in a shipping product.
  • Determination of which branch to pull from for Nouveau has to be made. Nouveau does not have a "release" branch.
  • Nouveau developers recommend taking the entire drm stack from the nouveau tree, and there are apparently some incompatibilities with other drivers when this is done. We may have to craft a solution for this.

BoF agenda and discussion



specs/KernelLucidKMS (last edited 2009-11-24 15:35:47 by sconklin)