History

Jooyung Han c36b18a443 Apexd runs in microdroid Previously, we ran only 'apexd-bootstrap' because 'apexd' crashes due to the lack of /data/apex in microdroid. Now apexd runs in "vm" mode. In vm mode, apexd only activates built-in apexes and block apexes. No data apexes, no session handling. Bug: 179342589 Test: MicrodroidTestCase Change-Id: I8c6a16c3b08010fcb008d822d0ba0e311c0a9985		2021-04-21 23:19:04 +09:00
..
signature	Add lib_microdroid_signature_proto with proto-full	2021-04-21 23:19:03 +09:00
Android.bp	Remove unused module	2021-04-21 21:34:20 +09:00
README.md	Move uboot_env.img to a new composite disk	2021-04-13 17:44:44 +09:00
build.prop	Add build.prop for microdroid	2021-04-06 21:25:57 +09:00
dummy_dtb.img	Build vendor_boot image for microdroid	2021-02-04 23:39:09 +09:00
empty_kernel	Add MicrodroidHostTestCases	2021-03-12 13:36:15 +09:00
fstab	Reland "Add microdroid_vendor"	2021-03-03 14:56:18 +00:00
init.rc	Apexd runs in microdroid	2021-04-21 23:19:04 +09:00
linker.config.json	Microdroid is built using android_system_image module type	2021-04-20 13:23:37 +09:00
microdroid_cdisk.json	Partitions are by default read-only.	2021-04-13 17:46:54 +09:00
microdroid_cdisk_env.json	Partitions are by default read-only.	2021-04-13 17:46:54 +09:00
microdroid_file_contexts	Add microdroid_file_contexts to build image	2021-02-03 14:50:28 +09:00
microdroid_vendor_file_contexts	Reland "Add microdroid_vendor"	2021-03-03 14:56:18 +00:00
plat_sepolicy_vers.txt	Reland "Add microdroid_vendor"	2021-03-03 14:56:18 +00:00
uboot-env-x86_64.txt	Enable verified boot for microdroid	2021-04-14 16:48:27 +09:00
uboot-env.txt	Enable verified boot for microdroid	2021-04-14 16:48:27 +09:00

README.md

Microdroid

Microdroid is a (very) lightweight version of Android that is intended to run on on-device virtual machines. It is built from the same source code as the regular Android, but it is much smaller; no system server, no HALs, no GUI, etc. It is intended to host headless & native workloads only.

Building

You need a VIM3L board. Instructions for building Android for the target, and flashing the image can be found here.

Then you install com.android.virt APEX. All files needed to run microdroid are included in the APEX, which is already in the yukawa (VIM3L) target. You can of course build and install the APEX manually.

$ source build/envsetup.sh
$ choosecombo 1 aosp_arm64 userdebug // actually, any arm64-based target is ok
$ m com.android.virt
$ adb install $ANDROID_PRODUCT_OUT/system/apex/com.android.virt.apex
$ adb reboot

Running

Copy the artifacts to the temp directory, create the composite image using mk_cdisk, and run it via crosvm. For now, some other files have to be manually created. In the future, you won't need these, and this shall be done via virtmanager.

$ adb shell 'cp /apex/com.android.virt/etc/microdroid_bootloader /data/local/tmp/bootloader'
$ adb shell 'cp /apex/com.android.virt/etc/fs/*.img /data/local/tmp'
$ adb shell 'cp /apex/com.android.virt/etc/uboot_env.img /data/local/tmp'
$ adb shell 'dd if=/dev/zero of=/data/local/tmp/misc.img bs=4k count=256'
$ adb shell 'cd /data/local/tmp; /apex/com.android.virt/bin/mk_cdisk /apex/com.android.virt/etc/microdroid_cdisk.json os_composite.img'
$ adb shell 'cd /data/local/tmp; /apex/com.android.virt/bin/mk_cdisk /apex/com.android.virt/etc/microdroid_cdisk_env.json env_composite.img'
$ adb shell 'cd /data/local/tmp; /apex/com.android.virt/bin/crosvm run --cid=5 --disable-sandbox --bios=bootloader --serial=type=stdout --disk=os_composite.img --disk=env_composite.img'

The CID in --cid parameter can be anything greater than 2 (VMADDR_CID_HOST).

ADB

$ adb forward tcp:8000 vsock:5:5555
$ adb connect localhost:8000

5 in vsock:5 should match with the CID number that was given to crosvm. 5555 must be the value. 8000 however can be any port in the development machine.

Done. Now you can log into microdroid. Have fun!

$ adb -s localhost:8000 shell