First you will need a device that is capable of running virtual machines. On arm64, this means a device which boots the kernel in EL2 and the kernel was built with KVM enabled. Unfortunately at the moment, we don't have an arm64 device in AOSP which does that. Instead, use cuttlefish which provides the same functionalities except that the virtual machines are not protected from the host (i.e. Android). This however should be enough for functional testing.
We support the following device:
Building Cuttlefish
source build/envsetup.sh lunch aosp_cf_x86_64_phone-userdebug m
Run Cuttlefish locally by
acloud create --local-instance --local-image
The instruction is here.
There are various tests that spawn guest VMs and check different aspects of the architecture. They all can run via atest.
atest VirtualizationTestCases.64 atest MicrodroidHostTestCases atest MicrodroidTestApp
If you run into problems, inspect the logs produced by atest. Their location is printed at the end. The host_log_*.zip file should contain the output of individual commands as well as VM logs.
You can spawn your own VMs by passing a JSON config file to the VirtualizationService via the vm tool on a rooted KVM-enabled device. If your device is attached over ADB, you can run:
cat > vm_config.json { "kernel": "/data/local/tmp/kernel", "initrd": "/data/local/tmp/ramdisk", "params": "rdinit=/bin/init" } adb root adb push <kernel> /data/local/tmp/kernel adb push <ramdisk> /data/local/tmp/ramdisk adb push vm_config.json /data/local/tmp/vm_config.json adb shell "start virtualizationservice" adb shell "/apex/com.android.virt/bin/vm run /data/local/tmp/vm_config.json"
The vm command also has other subcommands for debugging; run /apex/com.android.virt/bin/vm help for details.
Microdroid is a lightweight version of Android that is intended to run on pVM. You can manually run the demo app on top of Microdroid as follows:
TARGET_BUILD_APPS=MicrodroidDemoApp m apps_only dist adb shell mkdir -p /data/local/tmp/virt adb push out/dist/MicrodroidDemoApp.apk /data/local/tmp/virt/ adb shell /apex/com.android.virt/bin/vm run-app \ --debug full \ /data/local/tmp/virt/MicrodroidDemoApp.apk \ /data/local/tmp/virt/MicrodroidDemoApp.apk.idsig \ /data/local/tmp/virt/instance.img assets/vm_config.json
You can update CrosVM and the VirtualizationService by updating the com.android.virt APEX instead of rebuilding the entire image.
banchan com.android.virt aosp_arm64 // or aosp_x86_64 if the device is cuttlefish UNBUNDLED_BUILD_SDKS_FROM_SOURCE=true m apps_only dist adb install out/dist/com.android.virt.apex adb reboot
Checkout the Android common kernel and build it following the official guideline.
mkdir android-kernel && cd android-kernel repo init -u https://android.googlesource.com/kernel/manifest -b common-android12-5.10 repo sync FAST_BUILD=1 DIST_DIR=out/dist BUILD_CONFIG=common/build.config.gki.aarch64 build/build.sh -j80
Replace build.config.gki.aarch64 with build.config.gki.x86_64 if building for x86.
Then copy the built kernel to the Android source tree.
cp out/dist/Image <android_root>/kernel/prebuilts/5.10/arm64/kernel-5.10
Finally rebuild the com.android.virt APEX and install it by following the steps shown in Building and updating Crosvm and Virtualization.