This document describes one way to created the rcu-test-image file that contains the filesystem used by the guest-OS kernel. There are probably much better ways of doing this, and this filesystem could no doubt be smaller. It is probably also possible to simply download an appropriate image from any number of places. That said, here are the commands: ------------------------------------------------------------------------ dd if=/dev/zero of=rcu-test-image bs=400M count=1 mkfs.ext3 ./rcu-test-image sudo mount -o loop ./rcu-test-image /mnt # Replace "precise" below with your favorite Ubuntu release. # Empirical evidence says this image will work for 64-bit, but... # Note that debootstrap does take a few minutes to run. Or longer. sudo debootstrap --verbose --arch i386 precise /mnt http://archive.ubuntu.com/ubuntu cat << '___EOF___' | sudo dd of=/mnt/etc/fstab # UNCONFIGURED FSTAB FOR BASE SYSTEM # /dev/vda / ext3 defaults 1 1 dev /dev tmpfs rw 0 0 tmpfs /dev/shm tmpfs defaults 0 0 devpts /dev/pts devpts gid=5,mode=620 0 0 sysfs /sys sysfs defaults 0 0 proc /proc proc defaults 0 0 ___EOF___ sudo umount /mnt ------------------------------------------------------------------------ References: http://sripathikodi.blogspot.com/2010/02/creating-kvm-bootable-fedora-system.html https://help.ubuntu.com/community/KVM/CreateGuests https://help.ubuntu.com/community/JeOSVMBuilder http://wiki.libvirt.org/page/UbuntuKVMWalkthrough http://www.moe.co.uk/2011/01/07/pci_add_option_rom-failed-to-find-romfile-pxe-rtl8139-bin/ -- "apt-get install kvm-pxe" http://www.landley.net/writing/rootfs-howto.html http://en.wikipedia.org/wiki/Initrd http://en.wikipedia.org/wiki/Cpio http://wiki.libvirt.org/page/UbuntuKVMWalkthrough