Comment 8 for bug 906358

I did some more research on this problem and it's udevd itself. Activating the debug output gives me the following message after 60 seconds:

timeout, giving up waiting for workers to finish

This message comes from udevd.c:1626 when epoll_wait times out. After this message udevd will immediately exit without waiting for the other worker threads. I'm not sure why the kernel doesn't signal udevd.
I've also tested this with the recent kernel 3.0.0-15 from oneiric-propsed with the same result.
Maybe we should raise this bug as critical because Ubuntu is currently not really usable on a lvm partition.