Build a User Mode Linux kernel with your current toolchain.

  Get current kernel source, configure (I'm using miniconfig), build UML:

    wget http://kernel.org/pub/linux/kernel/v2.6/linux-2.6.17.tar.bz2
    tar xjvf linux-2.6.17.tar.bz2
    patch -p1 -i ../miniconfig.patch
    make miniconfig MINICONFIG=../linux-miniconfig-uml ARCH=um
      optional: make ARCH=um menuconfig (general setup->small systems->load all)
    make ARCH=um

      note: CONFIG_HZ error means it's distclean time.  You have leftover
      ARCH=i386 symlinks in your build directory.  Try again.

  Boot User Mode Linux with hostfs, demonstrate basic User Mode Linux.
    ./linux rootfstype=hostfs rw init=/bin/sh
      whoami
      mount -t procfs /proc /proc
      cat /proc/cpuinfo
      ps
      cat/proc/mounts
    exit - panics the kernel when PID 1 exits, but who cares?