GNU Mach: in user-mode?

[Ivan Shmakov]

        I wonder, is there a chance of getting GNU Mach to run as an
        user-mode application under a different (e. g., GNU/Linux, or
        Mach-based GNU/Hurd itself) system?  Is there any significant
        issues, beyond of simply severing all the ties to the real
        hardware (and providing the replacements deemed necessary)?

        NB:

        * The time and qualification necessary to deploy one or more
          GNU/Linux systems on a single host using User-Mode Linux is
          (to my experience) significantly lower than for the other
          solutions (KVM, Xen) known to me (indeed, two commands and a
          less-than-a-screen long configuration file, for Debian
          GNU/Linux host and guest.)  Perhaps the same would stand for
          GNU/Hurd and User-Mode Mach as well.

        * Running User-Mode Linux doesn't imply any privileged user
          intervention (contrary to both KVM and Xen) and thus gives
          more confidence in ``harmlessness'' of the solution.  Would
          the same hold true for Mach, it would, hopefully, attract more
          users to trying it.

        * ... And then, what about having GNU/Mach supplied with Debian
          GNU/Linux, at your service and fully ready to host one or more
          GNU/Hurd instances you've just wished for?