I was going to post this in "breakages" but I can't be sure.
Until yesterday I was quite happy running my system with all updates, using a patched 2.6.38-7 kernel with ATI propriety drivers, and no problems. I did yesterday's updates, and after the next reboot, no accelerated graphics drivers any more. I usually install using sgfxi, so fired it up and it reported a DKMS problem.
No problem, I thought, rebooted to a vanilla 2.6.38 kernel, and same problem. Restored a backup from a month ago, same problem.
I wiped and installed fresh, and tried the propriety driver again. Lo and behold, same problem. Tried the fglrx driver from the repos and that installed and worked (something which it has never done before for me).
So, wiped the new installation and restored my backup again, removed the old driver remnants and installed fglrx from the repository. Installed but left with a none-bootable system (behaviour I'm used to).
Removed the fglrx drivers and purged, but I left the fglrx-dkms-module in place and tried again with fglrx, but still no go. As a last report, switched to an older kernel (2.6.36-dmz3-liqourix) and tried sgfxi again. Drivers installed and working. So I'm back to a fully running system, but I'm completely baffled as to why the drivers suddenly refuse with 2.6.38 having been working happily for the past month. The ATI drivers haven't changed, so I can only assume something in an update broke it, and since I've completely wiped the system in order to fix it, I'm further assuming something in the grub updates, but I've tried reinstalling grub, pinning the grub version and even installing grub legacy with no luck.
Any ideas what may suddenly make a driver and kernel incompatible when they were compatible two days ago?