0d7f5bb540
Also moved to a subdirecory of /data/local/tmp, to keep things a litle tidier. Bug: 181869875 Test: ran the commands Change-Id: I9962e5165294c41a02bcc3b72501165dd85b7abe |
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.. | ||
signature | ||
Android.bp | ||
README.md | ||
build.prop | ||
dummy_dtb.img | ||
empty_kernel | ||
fstab | ||
init.rc | ||
linker.config.json | ||
microdroid_cdisk.json | ||
microdroid_cdisk_env.json | ||
microdroid_cdisk_userdata.json | ||
microdroid_file_contexts | ||
microdroid_payload.json | ||
microdroid_vendor_file_contexts | ||
uboot-env-x86_64.txt | ||
uboot-env.txt |
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
Create a config file, microdroid.json
:
{
"bootloader": "/data/local/tmp/microdroid/bootloader",
"disks": [
{
"image": "/data/local/tmp/microdroid/os_composite.img",
"writable": false
},
{
"image": "/data/local/tmp/microdroid/env_composite.img",
"writable": false
},
{
"image": "/data/local/tmp/microdroid/payload.img",
"writable": false
},
{
"image": "/data/local/tmp/microdroid/userdata_composite.qcow2",
"writable": true
}
]
}
Copy the artifacts to the temp directory, create the composite image using
mk_cdisk
, copy the VM config file, and run it via vm
. 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 root
$ adb shell 'mkdir /data/local/tmp/microdroid'
$ adb shell 'cp /apex/com.android.virt/etc/microdroid_bootloader /data/local/tmp/microdroid/bootloader'
$ adb shell 'cp /apex/com.android.virt/etc/fs/*.img /data/local/tmp/microdroid'
$ adb shell 'cp /apex/com.android.virt/etc/uboot_env.img /data/local/tmp/microdroid'
$ adb shell 'dd if=/dev/zero of=/data/local/tmp/microdroid/misc.img bs=4k count=256'
$ adb shell 'dd if=/dev/zero of=/data/local/tmp/microdroid/userdata.img bs=1 count=0 seek=4G'
$ adb shell 'mkfs.ext4 /data/local/tmp/microdroid/userdata.img'
$ adb shell 'cd /data/local/tmp/microdroid; /apex/com.android.virt/bin/mk_cdisk /apex/com.android.virt/etc/microdroid_cdisk.json os_composite.img'
$ adb shell 'cd /data/local/tmp/microdroid; /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/microdroid; /apex/com.android.virt/bin/mk_cdisk /apex/com.android.virt/etc/microdroid_cdisk_userdata.json userdata_composite.img'
$ adb shell '/apex/com.android.virt/bin/crosvm create_qcow2 --backing_file=/data/local/tmp/microdroid/userdata_composite.img /data/local/tmp/microdroid/userdata_composite.$ qcow2'
$ adb shell 'cd /data/local/tmp/microdroid; /apex/com.android.virt/bin/mk_payload /apex/com.android.virt/etc/microdroid_payload.json payload.img'
$ adb shell 'chmod go+r /data/local/tmp/microdroid/*-header.img /data/local/tmp/microdroid/*-footer.img'
$ adb push microdroid.json /data/local/tmp/microdroid/microdroid.json
$ adb shell "start virtmanager"
$ adb shell "RUST_BACKTRACE=1 RUST_LOG=trace /apex/com.android.virt/bin/vm run /data/local/tmp/microdroid/microdroid.json"
ADB
$ CID=10
$ adb forward tcp:8000 vsock:$CID:5555
$ adb connect localhost:8000
CID
should be the CID that vm
reported was assigned to the VM. You can also
check it with adb shell "/apex/com.android.virt/bin/vm list"
. 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