Is it by any means possible for me to get remote access to that system to do some more try&error? Otherwise I can just ask to to try to re-do the same steps setup-storage makes, manually. It's too strange.
I would be happy to give you a remote access but... can't reproduce the problem today, although I did 2 days ago. Same hardware, same setup-storage configuration, but quite a few packages have been updated, including experimental FAI. I just found out that a similar error message has also shown up during several successful installations, until 2 days ago, for example http://paste.debian.net/69022/
Today I've got twice the same result with preserve_lazy, where setup-storage claims that it will preserve volumes, nevertheless removes them, and then fails because it can't find them. But no kernel error.
http://paste.debian.net/69021/ -- Nicolas
