out-of-tree/qemu

out-of-tree/qemu

Qemu wrapper for kernel-related CI tasks. Supports GNU/Linux and macOS.

Features:

• Uses upstream virtualization -- KVM in GNU/Linux and Hypervisor.framework in macOS.
• Run files and kernel modules directly from local filesystem. No need to copy byself!
• Run commands inside qemu virtual machine at the same way as you run in it locally.

Installation

$ go get github.com/jollheef/out-of-tree/qemu

Generate root image

First of all we need to generate rootfs for run qemu.

GNU/Linux

$ sudo apt install -y debootstrap qemu
$ sudo qemu-debian-img generate sid.img

macOS

Note: qemu on macOS since v2.12 (24 April 2018) supports Hypervisor.framework.

$ brew install qemu

Because it's a very complicated to debootstrap qemu images from macOS, preferred way is to use Vagrant with any hypervisor.

$ brew cask install vagrant
$ vagrant plugin install vagrant-vbguest
$ cd $GOPATH/src/github.com/jollheef/out-of-tree/qemu/tools/qemu-debian-image
$ vagrant up && vagrant destroy -f

bionic.img, vmlinuz-bionic and initrd-bionic will be created in current directory.

Fill configuration file

$ $EDITOR $GOPATH/src/github.com/jollheef/out-of-tree/qemu/test.config.go

Run tests

$ go test -v

Usage

$ go get github.com/jollheef/out-of-tree/qemu

Minimal example:

kernel := qemu.Kernel{
	Name:       "Some kernel name",
	KernelPath: "/path/to/vmlinuz",
	InitrdPath: "/path/to/initrd", // if required
}
q, err := qemu.NewQemuSystem(qemu.X86_64, kernel, "/path/to/qcow2")
if err != nil {
	log.Fatal(err)
}

if err = q.Start(); err != nil {
	log.Fatal(err)
}
defer q.Stop()

output, err = q.Command("root", "echo Hello, World!")
if err != nil {
	log.Fatal(err)
}

// output == "Hello, World!\n"

More information and list of all functions see at go documentation project, or just run locally:

$ godoc github.com/jollheef/out-of-tree/qemu