As I read it, it installs on an LVM volume when left unattended (with default answers during the installation)?
It seems to be the default option of all modern installers when you leave partitioning to them; for some reason they think it's a good idea, and maybe for a number of reasons it really is...
But I've never seen any good from it, only running into problems every now and then. So generally I never use LVM unless there are weighty reasons for it (software RAID or something). Reasonably, I understand it to be a software layer on top of another software layer (LVM on top of partition table), so double the chance of it getting corrupted...
Anyway, did you try to boot with kernel parameter 'selinux=0'? Maybe that will resolve it and no more bothering about device dm-2?
And what I do on my computers is convert the whole disk to GPT as that partition table seems to be better protected. No XP installation possible with that, alas. But (maybe out of ignorance?) this seems to me a better option than LVM.
Maybe I'm mistaken?
All the best,