Ok, seems I have been running into the wrong direction. LVM+Xen works on x86, but fails on AMD64. I now think this has nothing to do with LVM at all (seems logical as Xen uses 254 as character device, and LVM as block device), but rather with blktapctl that does some weird stuff.
-- Problem with blktap and LVM (device numbers) https://launchpad.net/bugs/89133 -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
