Several people have reported in the past that during installation the system hangs "forever" (see bug bnc#722858) starting udev. The problem was that this did not appear reproduceable. It appeared once on my machine and when I brought the machine to Steffen to help debugging, I couldn't reproduce it. After some more tries, it was reproduceable but not everytime. Steffen initially thought it was a kernel race with module loading and thus we added "maxcpus=1" to the kernel command line. This made the bug less likely but it still happened. But now Christian, Coolo and myself had each a machine for reproduction and figured out that udevadm was waiting for some events and timing out after 10 minutes as that was the timeout in the installation system. So, one idea was to use the normal 30s as timeout so that fewer people noticed. In the end Coolo found the culprit: A bug in udev that got fixed in upstream udev a month ago that we got with a udev update a couple of months ago. Coolo fixed this with a new udev package that has been updated for 12.1 now. So, these hangs might have not only happened during installation but also at normal booting and I'm glad that Coolo decided to hunt down this bug.
Yeah, it's fun to debug bugs (if you're successfull) - especially if they are tricky and kind of
Heisenbugs. My test machines did 30+ reboots for testing - and will do
more tomorrow to check that the issues is really fixed.
Btw. besides this, a lot of other bugs have been fixed since openSUSE 12.1 RC2, see the list of checkins for 12.1 on the opensuse-commit mailing list.