Jerome Glisse had been working on Radeon GPU recovery support for some time, which should allow the graphics card / driver to (ideally) recover itself when it's locked-up. This new feature is coming after the Linux 2.6.34 kernel merge window has already been closed, but hopefully it will still be pulled by Linus Torvalds. Linus may not be happy about this code -- judging from his tirades in the past when David Airlie has called for larger pull requests later into the development cycle. However, this GPU recovery support should only be hit when the GPU is indeed locked up and it should not exacerbate any lock-ups.
Also coming as part of this pull request is working ATI R700 series HDMI KMS audio support.
This newest DRM pull request for the Linux 2.6.34 kernel can be found on the DRI mailing list. The Linux 2.6.34 kernel already features the GPU hybrid switching support, initial Evergreen KMS support for the Radeon HD 5000 series (but that goes without any form of 2D/3D/video acceleration support), hardware I2C engine support for Radeon DRM, a Nouveau interface break, Intel Sandy Bridge support, the R600 command stream checker, and various other improvements to the open-source Linux graphics stack.