Introduction
okLinux is a Linux distribution, specifically a fork of ChromiumOS.
oklinux.dev docs <- You are here
License
Architecture
🚧 Work In Progress 🚧
okLinux is a rootless Linux distribution. okLinux is meant to be run
inside a virtual machine. The virtual machine is managed by a fork of
crosvm called bldy.
Bldy uses JetStream for efficient transport of 9p over Quic for remote connections. As shown in the diagram below, the host machine runs the guest VM, which runs the bldy VM. The bldy VM mounts a remote file server (pangea) over 9p.
┌────────────────────────────────────────────────┐
│ remote file server (pangea) │
│ │
│ │
│ │
│ │
│ │
│ │
│ │
│ │
│ │
│ │
└────────────────────────────────────────────────┘
▲
│
│
│ ┌──────────────────────────────────────────────┐
│ │ │
│ │ host machine ┌────────────────────┐ │
│ │ │ guest VM │ │
│ │ │ │ │
│ │ │ │ │
│ │ │ │ │
│ │ │ │ │
│ │ ┌─────────────────┐ │ │ │
│ │ │ bldy │ │ │ │
│ │ │ │ │ │ │
│ │ │ │ │ │ │
│ │ │ │ │ │ │
│ │ │ │ │ │ │
│ │ │ │ │ │ │
└──────────────┼──┼────────┐ │ │ │ │
JetStream │ │ │ │ │ │ │
9p over Quic │ │ │ │ │ │ │
│ │ │ │ │ │ │
│ │ │ │ │ │ │
│ │ │ │ │ │ │
│ │ │ │ │ │ │
│ │ 9p over│virtio │ │ │ │
│ │ └◄───────┼──┤ │ │
│ │ │ │ │ │
│ │ │ │ │ │
│ └─────────────────┘ └────────────────────┘ │
│ │
└──────────────────────────────────────────────┘
Build script
🚧 Work In Progress 🚧
#!/bin/bash
# Read kernel version from kernel-version.txx to KERNEL_VERSION
KERNEL_VERSION=$(cat kernel-version.txt)
# Update the package list
apt-get update -y
# Install build dependencies
apt-get install \
libguestfs-tools \
-y
From kernel docs
In 2020, a better way to delay the mount until the time when we have access to the 9p modules from /lib/modules is to add _netdev as a mount parameter:
/data /data 9p trans=virtio,rw,_netdev 0 0
From CrosVM
Build a rootfs disk
This stage enjoys the most flexibility. There aren't any special requirements for a rootfs in crosvm, but you will at a minimum need an init binary. This could even be /bin/bash if that is enough for your purposes. To get you started, a Debian rootfs can be created with debootstrap. Make sure to define $CHROOT_PATH.
truncate -s 20G debian.ext4
mkfs.ext4 debian.ext4
mkdir -p "${CHROOT_PATH}"
sudo mount debian.ext4 "${CHROOT_PATH}"
sudo debootstrap stable "${CHROOT_PATH}" http://deb.debian.org/debian/
sudo chroot "${CHROOT_PATH}"
passwd
echo "tmpfs /tmp tmpfs defaults 0 0" >> /etc/fstab
echo "tmpfs /var/log tmpfs defaults 0 0" >> /etc/fstab
echo "tmpfs /root tmpfs defaults 0 0" >> /etc/fstab
echo "sysfs /sys sysfs defaults 0 0" >> /etc/fstab
echo "proc /proc proc defaults 0 0" >> /etc/fstab
exit
sudo umount "${CHROOT_PATH}"
CrosVM Notes
🚧 Work In Progress 🚧