| commit | ed3b1ca12caf596e879feb4bc71568d482c64649 | [log] [tgz] |
|---|---|---|
| author | Bowgo Tsai <bowgotsai@google.com> | Mon Mar 26 22:10:57 2018 +0800 |
| committer | Bowgo Tsai <bowgotsai@google.com> | Mon Mar 26 23:16:06 2018 +0800 |
| tree | d54546d5951990db8c4bbd5f2e69c3844534a281 | |
| parent | 3cf75cf2bb9f61f27e74af91c1811a92b7aa4982 [diff] |
Products launching with API 28 needs system-as-root
With project Treble, it's possible to only update system.img across
Android major releases without changing other partitions. However,
for non-A/B devices, ramdisk cannot be updated via a system-only OTA
because it resides in /boot partition.
This leads to two major incompatibility issues:
- The older /init in ramdisk might not be able to parse the *.rc files
on /system.
- The ramdisk contains /init.rc, which also may be out of date compared to
what is required for the new /system.
Therefore, for new devices launched in P with full Treble support, ramdisk
should be merged into system.img by setting
BOARD_BUILD_SYSTEM_ROOT_IMAGE := True.
Upgrading devices can keep using non-system-as-root configuration.
Bug: 64194858
Test: manual makefile prodding
Change-Id: Ic04c63bd2aac3afa686a6f5cb124beebbcd6a5ee
This is the Makefile-based portion of the Android Build System.
For documentation on how to run a build, see Usage.txt
For a list of behavioral changes useful for Android.mk writers see Changes.md
For an outdated reference on Android.mk files, see build-system.html. Our Android.mk files look similar, but are entirely different from the Android.mk files used by the NDK build system. When searching for documentation elsewhere, ensure that it is for the platform build system -- most are not.
This Makefile-based system is in the process of being replaced with Soong, a new build system written in Go. During the transition, all of these makefiles are read by Kati, and generate a ninja file instead of being executed directly. That's combined with a ninja file read by Soong so that the build graph of the two systems can be combined and run as one.