If you run into this error message while booting a Xen DomU which does not have encrypted devices and your Dom0 is on an encrypted partition, then you'll be as puzzled as I am and these people. So far, the only workaround I know is to start the DomU with serial console attached (xm create -c domuname.cfg) and hit return a couple times until it gives up to mount the seemingly encrypted root device and continues to boot the DomU.

This issue is, however, very annoying and breaks any attempts of automation of DomU startups. The problem seems to be a combination of two facts:

* the DomU uses the same initrd image as the DomO

* cryptsetup-root (as contained in the initrd) does not actually test whether the target device it is to mount is actually a compatible device but dumbly expects that it must be one if it is configured as such and thus keeps trying to mount it.

A better workaround or even a fix would be greatly appreciated. I know of at least three other parties who are running into the same issue but have not yet found a better solution. I guess I should file a bug but I'm not sure which package to file it against.