Hypervisor

The Zircon hypervisor can be used to run a guest operating system. It is a work in progress.

These instructions will guide you through creating minimal Zircon and Linux guests. For instructions on building a more comprehensive linux guest system see Hypervisor Benchmarking.

Running a guest

To run a guest using the hypervisor, you must create a bootfs image containing the guest and use the guest app to launch it.

Note: guest only supports the Zircon and Linux kernels.

On your host device, from the Zircon directory, run:

scripts/build-zircon-x86-64

# Optional: Build Linux, an initial RAM disk, and an EXT2 file-system.
system/uapp/guest/scripts/mklinux.sh
system/uapp/guest/scripts/mksysroot.sh -ri

# Optional: Build a GPT disk image for Zircon guests.
system/uapp/guest/scripts/mkgpt.sh

system/uapp/guest/scripts/mkbootfs.sh zircon-pc-x86-64
build-zircon-pc-x86-64/tools/bootserver \
    build-zircon-pc-x86-64/zircon.bin \
    build-zircon-pc-x86-64/bootdata-with-guest.bin

Zircon guest

After netbooting the target device, to run Zircon:

/boot/bin/guest -r /boot/data/bootdata.bin /boot/data/zircon.bin

To run Zircon using a GPT disk image:

/boot/bin/guest \
    -b /boot/data/zircon.gpt \
    -r /boot/data/bootdata.bin \
    /boot/data/zircon.bin

Linux guest

After netbooting the target device, to run Linux using an initial RAM disk:

/boot/bin/guest -r /boot/data/initrd /boot/data/bzImage

To run Linux using a read-only EXT2 root file-system:

/boot/bin/guest \
    -b /boot/data/rootfs.ext2 \
    -c 'root=/dev/vda ro init=/init' \
    /boot/data/bzImage

To run Linux using a writable EXT2 root file-system:

cp /boot/data/rootfs.ext2 /boot/data/rootfs-rw.ext2

/boot/bin/guest \
    -b /boot/data/rootfs-rw.ext2 \
    -c 'root=/dev/vda rw init=/init' \
    /boot/data/bzImage

Linux also supports an interactive graphical framebuffer:

/boot/bin/guest \
    -g \
    -r /boot/data/initrd \
    -c 'console=tty0' \
    /boot/data/bzImage

This will cause the guest to gain control of the framebuffer. Keyboard HID events will be passed through to the guest using a virito-input device (automatically enabled when the GPU is enaled with -g). You can toggle back to the host virtcon by pressing Alt+Esc.