Install Ubuntu on QEMU (RISC-V)

Prerequisites

To boot a RISC-V virtual machine you will need the following packages installed:

  • opensbi – OpenSBI implements the RISC-V SBI

  • qemu-system-misc (from qemu) – QEMU is used to emulate a RISC-V machine

  • u-boot-qemu (from u-boot) – U-Boot is the firmware implementing the UEFI API and loads GRUB

The packages can be installed with the following commands:

sudo apt update
sudo apt install opensbi qemu-system-misc u-boot-qemu

Using the pre-installed server image

  1. Download one of the supported images:

  2. Unpack the image:

    xz -dk ubuntu-24.04.1-preinstalled-server-riscv64.img.xz

  3. Optionally, if you want a larger disk, you can expand the disk (the file-system will be automatically resized too):

    qemu-img resize -f raw ubuntu-24.04-preinstalled-server-riscv64.img +5G

  4. Next use u-boot-qemu to boot the virtual machine. A working example with all the options is:

    qemu-system-riscv64 \
    -machine virt -nographic -m 2048 -smp 4 \
    -kernel /usr/lib/u-boot/qemu-riscv64_smode/uboot.elf \
    -device virtio-net-device,netdev=eth0 -netdev user,id=eth0 \
    -device virtio-rng-pci \
    -drive file=ubuntu-24.04-preinstalled-server-riscv64.img,format=raw,if=virtio

    The important options to use are:

    • QEMU’s generic virtual platform is selected by -machine virt

    • The first stage firmware booted by QEMU is OpenSBI. Before QEMU 7.0 this had to be specified by the -bios option. This option is not needed with QEMU 7.0 or higher. It cannot be used with KVM.

    • The second stage firmware U-Boot is loaded into memory via -kernel /usr/lib/u-boot/qemu-riscv64_smode/uboot.elf

    One can use pass through networking, adjust memory (-m) and CPU counts (-smp) as needed.

  5. Watch the serial console output and wait for cloud-init to complete. It will show a line with the text ‘Cloud-init finished’:

    [   68.346028] cloud-init[703]: Cloud-init v. 22.2-0ubuntu1~20.04.3 finished at Thu, 22 Sep 2022 11:35:28 +0000. Datasource DataSourceNoCloud [seed=/var/lib/cloud/seed/nocloud-net][dsmode=net].  Up 68.26 seconds

  6. Login with the user ubuntu and the default password ubuntu; you will be asked to choose a new password

cloud-init integration

The image provides a CIDATA partition as fallback data-source for cloud-init. It configures sudo user ubuntu with password ubuntu and uses DHCP to set up networking. You will be asked to change the password on first login.

If you wish to customize the user password, networking information, or add SSH keys, etc., please, mount the CIDATA partition, and adjust the meta-data and user-data files as needed. In a cloud setup you can rename or delete the files to ensure that only data provided via the network is used.

Using the live server image

Installing live server image

  1. Download one of the supported images:

  2. Unpack the disk image:

    gzip -d ubuntu-22.04.5-live-server-riscv64.img.gz

  3. Create the disk image on which you will install Ubuntu; 16 GiB should be enough

    fallocate -l 16G disk

  4. Start the installer with:

    qemu-system-riscv64 -machine virt -m 4G -smp cpus=2 -nographic \
    -kernel /usr/lib/u-boot/qemu-riscv64_smode/u-boot.bin \
    -netdev user,id=net0 \
    -device virtio-net-device,netdev=net0 \
    -drive file=ubuntu-22.04.5-live-server-riscv64.img,format=raw,if=virtio \
    -drive file=disk,format=raw,if=virtio \
    -device virtio-rng-pci

  5. Follow the installation steps in Ubuntu Server installation tutorial

When rebooting we have to remove the installer image. Otherwise the installer will restart.

U-Boot gives you a 2 second time window to press the Enter key to reach the U-Boot console. In U-Boot’s console you can use the poweroff command to stop QEMU. Another option to exit QEMU is pressing keys CTRL-a followed by key x.

Running Ubuntu

To run your installed Ubuntu image use:

qemu-system-riscv64 -machine virt -m 4G -smp cpus=2 -nographic \
    -kernel /usr/lib/u-boot/qemu-riscv64_smode/u-boot.bin \
    -netdev user,id=net0 \
    -device virtio-net-device,netdev=net0 \
    -drive file=disk,format=raw,if=virtio \
    -device virtio-rng-pci

Cloud-init seed

Sample files for a cloud-init seed are present on the FAT partition labeled “CIDATA”. See Configure your board for headless use for more information.

Limitations

  • The number of virtual CPUs was limited to 8 before QEMU 7.0. The limit was raised in QEMU 7.0 to 512.