aarch64qemu

Setting up a Ubuntu 14.04 or Debian 8 (jessie) arm64 VM

This is mainly a notes dump and should be used for reference. This guide assumes:

*Ubuntu 14.04 (or Debian 8) hypervisor/host with bridge networking
*Knowledge of qemu
*Knowledge of debootstrap

Limitations of the qemu-system-aarch64 emulator on x86 include only being able to emulate one CPU and no KVM support.

#Install required packages
sudo apt-get install debootstrap qemu-utils qemu

#Install build deps for qemu (apt-src must be enabled in sources.list)
sudo apt-get build-dep qemu

#Download the latest qemu source and build for a target of aarch64
git clone git://git.qemu.org/qemu.git qemu.git
cd qemu.git
./configure --target-list=aarch64-softmmu
make -j4
sudo make install

#Binary installs to
/usr/local/bin/qemu-system-aarch64

#Create a 60GB qcow2 image that the VM will use as /
qemu-img create -f qcow2 /srv/chroots/trusty.qcow2 60G

#Mount qcow as nbd device so we can use deboostrap on it and as a chroot later
modprobe -av nbd
qemu-nbd -c /dev/nbd0 /srv/chroots/trusty.qcow2

#Create partition on ndb0 and set the type to linux. Optionally you can also setup a swap partition.
fdisk /dev/nbd0

#Create an ext4 filesystem on new partition
mkfs.ext4 /dev/nbd0p1

#Mount partition on /mnt
mount -t ext4 /dev/nbd0p1 /mnt

#Run first-stage debootstrap for arm64
debootstrap --arch=arm64 --keyring=/usr/share/keyrings/ubuntu-archive-keyring.gpg --verbose --foreign trusty /mnt/

#Copy arm64 qemu binary into chroot
cp /usr/bin/qemu-aarch64-static /mnt/usr/bin/

#Go into chroot
chroot /mnt/ /bin/bash

#Run second stage of debootstrap while in chroot
/debootstrap/debootstrap --second-stage

#Add trusty arm64 ports to sources.list to install kernel in chroot
deb http://ports.ubuntu.com/ubuntu-ports/ trusty main universe multiverse restricted
deb http://ports.ubuntu.com/ubuntu-ports/ trusty-updates main universe multiverse restricted
deb http://ports.ubuntu.com/ubuntu-ports/ trusty-security main universe multiverse restricted
deb http://ports.ubuntu.com/ubuntu-ports/ trusty-proposed main universe multiverse restricted

deb-src http://ports.ubuntu.com/ubuntu-ports/ trusty main universe multiverse restricted
deb-src http://ports.ubuntu.com/ubuntu-ports/ trusty-updates main universe multiverse restricted
deb-src http://ports.ubuntu.com/ubuntu-ports/ trusty-security main universe multiverse restricted
deb-src http://ports.ubuntu.com/ubuntu-ports/ trusty-proposed main universe multiverse restricted

#If installing Debian Jessie, the steps are similar
qemu-img create -f qcow2 /srv/chroots/jessie.qcow2 60G
modprobe -av nbd
qemu-nbd -c /dev/nbd0 /srv/chroots/jessie.qcow2
mkfs.ext4 /dev/nbd0p1
mount -t ext4 /dev/nbd0p1 /mnt
apt-get install debian-archive-keyring
apt-key add /usr/share/keyrings/debian-archive-keyring.gpg
mkdir -p /mnt/usr/bin
cp /usr/bin/qemu-aarch64-static /mnt/usr/bin/
debootstrap  --arch=arm64 --keyring /usr/share/keyrings/debian-archive-keyring.gpg  --exclude=debfoster jessie /mnt/ http://ftp.debian.org/debian
chroot /mnt/ /bin/bash

#Add jessie arm64 ports to sources.list to install kernel in chroot
deb http://ftp.debian.org/debian/ jessie main contrib non-free
deb http://ftp.debian.org/debian/ jessie-updates main contrib non-free

deb-src http://ftp.debian.org/debian/ jessie main contrib non-free
deb-src http://ftp.debian.org/debian/ jessie-updates main contrib non-free

#Continue here for both Ubuntu and Debian
#update apt sources
apt-get update

#Install kernel and headers
##Ubuntu
apt-get install linux-generic linux-generic-headers
##Debian
apt-get install linux-image-arm64 linux-headers-arm64

#Exit chroot

#Copy linux kernel and initrd from chroot to /srv/chroots/ on hypervisor
cp /mnt/boot/vmlinux* /srv/chroots/
cp /mnt/boot/initrd* /srv/chroots/

#Umount chroot
umount /mnt

#Start up the VM in ro mode first without an initrd so we can get to a rescue shell to finish configuration
/usr/local/bin/qemu-system-aarch64 -cpu cortex-a57 -machine type=virt -nographic -smp 1 -m 8192 -kernel /srv/chroots/vmlinuz-3.13.0-34-generic -drive file=/srv/chroots/trusty.qcow2,if=none,id=blk -device virtio-blk-device,drive=blk -device virtio-net-device,netdev=net0,mac=00:00:00:00:00:00 -netdev tap,id=net0 --append "root=/dev/vda1 ro console=ttyAMA0 --"

#The boot will halt with an error about not being about to mount filesystems, choose continue to drop to a rescue shell and remount / as rw
mount -o remount,rw /

#Set hostname to something unique
hostname NEWHOSTNAME

#Setup networking with DHCP
dhclient eth0

#Setup a swap file so we don't run out of memory
dd if=/dev/zero of=/swapfile bs=1M count=4096
chmod 600 /swapfile
mkswap /swapfile
swapon /swapfile

#Install ssh and other packages
#Ubuntu
apt-get install ssh openssh-server perl netcat netcat6 bind9utils dnsutils libio-socket-ssl-perl libnet-ssleay-perl ldap-utils libtime-modules-perl lsb sysv-rc-conf dkms linux-headers-generic make bzip2 git curl build-essential

#Debian
apt-get install ssh openssh-server perl netcat netcat6 bind9utils dnsutils libio-socket-ssl-perl libnet-ssleay-perl ldap-utils libtime-modules-perl lsb sysv-rc-conf dkms linux-headers-arm64 make bzip2 git curl build-essential

#Test sshd starts and enable on boot
sudo service ssh start
update-rc.d ssh defaults

#Additional Configuration
*add swap to /etc/fstab if desired
*set root password and user if desired
*set networking to static if desired

#halt VM
halt -p

#Start VM with 8GB of memory, bridge networking, initrd, and rw / which will fully boot
/usr/local/bin/qemu-system-aarch64 -cpu cortex-a57 -machine type=virt -nographic -smp 1 -m 8192 -kernel /srv/chroots/vmlinuz-3.13.0-34-generic -initrd /srv/chroots/initrd.img-3.13.0-34-generic -drive file=/srv/chroots/trusty.qcow2,if=none,id=blk -device virtio-blk-device,drive=blk -device virtio-net-device,netdev=net0,mac=00:00:00:00:00:00 -netdev tap,id=net0 --append "root=/dev/vda1 rw console=ttyAMA0 --"

#Log in via ssh as root or user and use system normally

#References
http://www.bennee.com/~alex/blog/2014/05/09/running-linux-in-qemus-aarch64-system-emulation-mode/
https://gmplib.org/~tege/qemu.html