@Dave, thanks for downgrading all those components to help isolate the change. Can you confirm that you are booting into the old X server?
$ apt-cache policy xserver-xorg-core
If it downgraded correctly it should show version 2:1.10.2-1ubuntu1.
Also post your Xorg.0.log and dmesg from after all the downgrades so we have it, then go ahead and upgrade back to latest if you want.
I notice that some of the changes in udev 171 caused boot failures in earlier versions. Has anyone tried downgrading back to version 167-0ubuntu3? That would probably be what I'd try next.
I took another look through the list of recently upgraded packages, but I don't see any others that strike me as potentially relevant. I think for now concentrate on udev (and xserver, if you find it didn't downgrade).
@Dave, thanks for downgrading all those components to help isolate the change. Can you confirm that you are booting into the old X server?
$ apt-cache policy xserver-xorg-core
If it downgraded correctly it should show version 2:1.10.2-1ubuntu1.
Also post your Xorg.0.log and dmesg from after all the downgrades so we have it, then go ahead and upgrade back to latest if you want.
I notice that some of the changes in udev 171 caused boot failures in earlier versions. Has anyone tried downgrading back to version 167-0ubuntu3? That would probably be what I'd try next.
I took another look through the list of recently upgraded packages, but I don't see any others that strike me as potentially relevant. I think for now concentrate on udev (and xserver, if you find it didn't downgrade).