[GUIDE][HACK]Cross Compiling for OSX on Linux with AOSP - Android Software/Hacking General [Developers Only]

Hi Folks
I wasn't sure where this should belong but as it is a bit of an Hack this forum is probably the most appropriate
Introduction
This short tutorial will show you how to patch the Android Build System to allow you to cross-compile Android AOSP host tools ( adb, fastboot etc ) for OSX using a linux based machine. This is something Google said was impossible or at the very least unsupported.
Assumptions
You have a linux based machine and working copy of the AOSP source tree.
You can/have successfully compile(d) a full Android Release from this tree.
A basic idea of how the Android Build System works is beneficial.
Getting Started
I've set-up a git repository which contains a binary copy of the OSX SDK 10.6 and the apple-darwin10-gcc cross compiler. So first things first. open a terminal and set the root of the AOSP sources tree to the current directory.
STAGE 1: Copy the OSX SDK
Step 1.
Clone the repo with the SDK and toolchain
Code:
git clone https://github.com/trevd/android_platform_build2.git build2
Step 2.
Create /Developer directory at your filesystem root, this is a known location for the SDKs
Code:
sudo mkdir /Developer
sudo chown $USER.$USER /Developer
Step 3.
Copy and unpack the SDK package
Code:
cp build2/osxsdks10.6.tar.gz /Developer
cd /Developer
tar -zxvf osxsdks10.6.tar.gz
rm osxsdks10.6.tar.gz
cd - # back to aosp root
STAGE 2 : Swapping the Toolchain
This is where the fun begins :laugh:
The Android Build system has the majority of the infrastructure in place already to build for OSX, the only problem is that you need OSX to build for OSX. However we can remedy that with a couple of dirty hacks :laugh:.
The prebuilts/gcc/darwin-x86 directory contains a toolchain compatible with osx ( mach-o binaries ). We are going to swap this for a linux compatible ( elf ) executables.
Step 4:
Copy and unpack the elf compatible darwin cross toolchain
Code:
cp build2/i686-apple-darwin-4.2.1.tar.gz prebuilts/gcc/linux-x86/host
cd prebuilts/gcc/linux-x86/host
tar -zxvf i686-apple-darwin-4.2.1.tar.gz
cd - # back to aosp root
Step 5:
Remove the mach-o binaries and symlink the elf binaries in it's place
Code:
cd prebuilts/gcc
rm -rf darwin-x86
ln -s linux-x86 darwin-x86
cd - # back to aosp root
Step 6:
We also need to replace the mach-o version of the ccache executable which live in the prebuilt/misc directory
Code:
cd prebuilts/misc
rm -rf darwin-x86
ln -s linux-x86 darwin-x86
cd - # back to aosp root
STAGE 3: Patching the build system .mk files
We need to patch a couple of files in the build directory namely the build/core/combo/HOST_darwin-x86.mk the main crux of this is swapping the ar tool for libtool so static libraries can be created without error.
Code:
patch -p1 < build2/build.patch
If the patch has been applied successfully you should see the following
Code:
patching file system/core/adb/Android.mk
patching file build/core/combo/HOST_darwin-x86.mk
patching file build/core/combo/select.mk
patching file build/core/envsetup.mk
patching file build/envsetup.sh
You are now ready to cross compile!! :good: ..... well not quite, but nearly.... here's why!
The Android Build System will attempt to build both the Target and Host files for most modules so I'd advise using a lunch option which already has a full target built for it or alternatively you can build the generic sdk using the following commands at the AOSP source tree root.
Code:
. build/envsetup.sh
lunch sdk-eng
make sdk
This will stop target dependency errors occurring when you build individual modules.
NOW we're ready to cross compile.
STAGE 4: Building Modules
At present module build is very much a piecemeal process. To build adb for example we need to build the dependencies first. This is not too onerous as most host modules have very few dependencies.
Building adb
adb has dependencies on the following libraries
Code:
external/zlib
external/openssl
system/core/liblog
system/core/libcutils
system/core/libzipfile
I've found the easiest way to compile the dependencies is to navigate to each directory in turn an use to "mm" build system command to compile the individual module. the commands I run to compile adb are as follows.
From AOSP Source Root
Code:
cd external/zlib
USE_DARWIN=true mm -j8
cd ../openssl
USE_DARWIN=true mm -j8
croot # go back to the AOSP root
cd system/core/liblog
USE_DARWIN=true mm -j8
cd ../libcutils
USE_DARWIN=true mm -j8
cd ../libzipfile/
USE_DARWIN=true mm -j8
cd ../adb
USE_DARWIN=true mm -j8
All being well you should now have and adb binary located at out/host/darwin-x86/bin/adb. running the file command on this binary should produce the following output
Code:
adb: Mach-O executable i386
Conclusion
Although this method is a little rough and ready, it should produce the desired results if you need to cross compile for OSX. The eventual goal would be to compile a full OSX Android SDK on linux in a similar manner to the way the windows-sdk is currently compiled. This requires more investigation as compiling the windows sdk on linux employs a little bit of trickery on the part of the build system.
Final Notes and FAQs:
Why can't I just type make <module> from the root?
Doing this triggers building of additional modules such as LLVM and clang which are to deployed out/host/darwin-x86/bin the build system then attempts to use binary later on. These are obviously built for the Mach-o architecture and as such are incompatible with the linux. This results in a build error which can and would be resolved by the above mentioned trickery ( see conclusion )

I use OSX binaries (along with Windows and my native Linux) in one of my projects. Thanks, I have always relied on finding compiled binaries elsewhere. Lack of an OSX aapt held up an update at one point.
One of those things that you don't really use until you need it, but I will try to remember to give it a shot. I don't have any doubt that it works.

mateorod said:
I use OSX binaries (along with Windows and my native Linux) in one of my projects. Thanks, I have always relied on finding compiled binaries elsewhere. Lack of an OSX aapt held up an update at one point.
One of those things that you don't really use until you need it, but I will try to remember to give it a shot. I don't have any doubt that it works.
Click to expand...
Click to collapse
Thanks. Yes this really is an edge case. Hopefully It will help some folks out.
Regarding aapt in particular.... It's perfectly possible to build aapt, however, we need to do some slight of hand with the clang and clang++ executables as libpng on which aapt depends uses these 2 binaries as part of it's build process.
Here's the build list and the clang trick if you want to try it some time.
Code:
build/libs/host
external/expat
external/zlib
system/core/liblog
system/core/libcutils
mkdir out/host/darwin-x86/bin
cp out/host/linux-x86/bin/clang out/host/darwin-x86/bin
cp out/host/linux-x86/bin/clang++ out/host/darwin-x86/bin
external/libpng
frameworks/base/libs/androidfw
frameworks/native/libs/utils
frameworks/base/tools/aapt
I started off with a clean out/host/darwin-x86 directory so I didn't miss any dependencies.
like I mentioned the clang "swap out" is something the make win_sdk option does automatically so with it a little more research I should be able to get the mac build to do the same but you'll have to "fill yer boots" with the ghetto method for now
For reference here's a link to the sdk building instructions http://tools.android.com/build which describes how to cross compile the windows sdk on linux ( in case anyone was wondering what the hell i'm on about)

My use case has come up
I will be cross-compiling for OSX today...specifically with aapt in mind. I will report back, but I fully expect it to work as described.

mateorod said:
My use case has come up
I will be cross-compiling for OSX today...specifically with aapt in mind. I will report back, but I fully expect it to work as described.
Click to expand...
Click to collapse
Cheers Man!
Hopefully no bitrot has crept in since april and now. I know I've changed my OS version since to Lubuntu 13.04, not like the OS version really matters any.
mateorod said:
but I fully expect it to work as described.
Click to expand...
Click to collapse
Then you Sir, are either Drunk or a Fool! LOL Keep expectations Quantum and only decided when the result is observed a'la Schrodinger Cat

okay...So I was trying to compile SlimRom (so as to get an OSX aapt binary with the SlimRom changes) and things did not necessarily go as planned. There were enough changes to the SlimRom android_build that your build/build.patch does not apply cleanly. I spent some time and tried to modify the patch so that it would work for both SlimRom, AOSP and probably others, but each android_build repo has some differences in surrounding the HOST_AR line, so commenting that just was not portable between flavors. Not cool.
Anyway, turns out that this method does not quite work out of the box for non-AOSP versions (not that you claimed that it did). I got some unfamiliar errors related to (I believe) some OSX toolchains. But in both times I tried this, I actually had to pretty immediately swap out of that flavor and so I was unable to do much debugging. (I keep all the flavors I build {CM, AOKP, SlimRom, PAC, PA, OpenPDroid, etc, etc, etc} all layered in one android/system/jellybean directory. It saves a ton of space, but only allows me to do one thing at a time.)
So the only feedback I have is nothing...I even formatted my hard drive in-between and forgot to put up a paste, so the errors are currently lost to history.
Things that I noticed, for better or worse
You recommend putting the SDKs in the root dir. I believe the documentation is recommending the Developer be placed in home (as per the SDK/ADT bundle docs).
You might want a
Code:
mv android_platform_build2 build2
line. I normally wouldn't bother, but it looks like you are trying to post a line-by-line guide.
I would put the recommendation that a full build be available to the out folder (or a built generic sdk) right at the top, since it is a preliminary step. I had to revert my handwritten changes, then build, then reapply the changes and rebuild since I thought it needed a clean out dir.
Did you have any trouble with git reverting the toolchain swap? On two separate machines, I had to go so far as to delete .repo/projects/prebuilts/gcc/* and prebuilts/gcc/darwin-x86/arm/arm-eabi-4.6. It kept complaining of that the project in the .repo folder was a bad match. No amount of git trickery (which I am not terrible at) let me back out more easily.
I am willing to try again...but I have some other small things to attend to first. It is an admirable hack you have here sir. I will return to it soon and report back once more.

mateorod said:
okay...So I was trying to compile SlimRom (so as to get an OSX aapt binary with the SlimRom changes) and things did not necessarily go as planned. There were enough changes to the SlimRom android_build that your build/build.patch does not apply cleanly. I spent some time and tried to modify the patch so that it would work for both SlimRom, AOSP and probably others, but each android_build repo has some differences in surrounding the HOST_AR line, so commenting that just was not portable between flavors. Not cool.
Anyway, turns out that this method does not quite work out of the box for non-AOSP versions (not that you claimed that it did). I got some unfamiliar errors related to (I believe) some OSX toolchains. But in both times I tried this, I actually had to pretty immediately swap out of that flavor and so I was unable to do much debugging. (I keep all the flavors I build {CM, AOKP, SlimRom, PAC, PA, OpenPDroid, etc, etc, etc} all layered in one android/system/jellybean directory. It saves a ton of space, but only allows me to do one thing at a time.)
So the only feedback I have is nothing...I even formatted my hard drive in-between and forgot to put up a paste, so the errors are currently lost to history.
Things that I noticed, for better or worse
You recommend putting the SDKs in the root dir. I believe the documentation is recommending the Developer be placed in home (as per the SDK/ADT bundle docs).
You might want a
Code:
mv android_platform_build2 build2
line. I normally wouldn't bother, but it looks like you are trying to post a line-by-line guide.
I would put the recommendation that a full build be available to the out folder (or a built generic sdk) right at the top, since it is a preliminary step. I had to revert my handwritten changes, then build, then reapply the changes and rebuild since I thought it needed a clean out dir.
Did you have any trouble with git reverting the toolchain swap? On two separate machines, I had to go so far as to delete .repo/projects/prebuilts/gcc/* and prebuilts/gcc/darwin-x86/arm/arm-eabi-4.6. It kept complaining of that the project in the .repo folder was a bad match. No amount of git trickery (which I am not terrible at) let me back out more easily.
I am willing to try again...but I have some other small things to attend to first. It is an admirable hack you have here sir. I will return to it soon and report back once more.
Click to expand...
Click to collapse
Hi
Thanks for this, It sounds like you've suffered an exercise in frustration there. I wasn't aware that "SlimRom" had a different aapt ( just out of general ignorance and not having paid any attention )
SDK - My Tree last time I used this was /Developer directory in the root - I think It comes from what the toolchain is expecting, I just gave it what it wants
mv android_platform_build2 build2 - Yep I did mean that it's the git clone line which wants changing
Code:
git clone https://github.com/trevd/android_platform_build2.git build2
SDK Recommendation - I shall move that to the top, even though it is already in there, It should probably be highlighted better and possible it's own "Stage"
Reverting the toolchain - Ahh , It appears I work slightly different from most in this respect. I have a general mistrust of SCM's ( I lost too much code on too many different SCM's, Probably through my own inability to use them correctly but ) what I do to revert to change is
Code:
cd prebuilts/gcc/darwin-x86/host/
rm -rf i686-apple-darwin-4.2.1
repo sync i686-apple-darwin-4.2.1
You can do this "trick" on any project in the source tree it's only on rare occasions where I screwed up badly that I have to delete anything in .repo/projects but I also have my distro in their own individual directories with there own full git trees, which is a massive waste of space and has a ton of redundancy due to the AOSP repositories being mirror by every single one but switching between them is a lot easier
If SlimRom's changes are localized to aapt, I'd be more inclined to drop it into the AOSP build and try that... If you have a link to slimrom's frameworks/base repository I'll grab it and try it myself.
On a final note there's a "full version" of the HOST_darwin make file in the build2/core/combo directory the changes to envsetup.mk and select.mk are minimal and can easily be applied manually. You don't need to patch the adb makefile if your not building it.
Again Thanks for the feedback

Related

[Q] Cross compiling C software for my android

Hi,
I've download the Android source with "repo", and it includes cross compiler toolchains for various architectures.
I want to build a package (for now, mtd-utils) for my android phone (a htc hero), but I'm having limited success understanding how to get this working. I was thinking there was something I could do, like change my $PATH and set up some other environment variables, that would use the tools from the toolchain instead of the system default ones, so that the binaries would be built for the phone instead of for my computer. But it certainly doesn't seem to be that easy...
I've reverted to attempting a "Hello world" program, but when I try to compile even that using the included toolchain tools, I run into trouble:
Code:
$ $HOME/src/mydroid/prebuilt/linux-x86/toolchain/arm-eabi-4.4.0/bin/arm-eabi-gcc -static -o hello hello.c
hello.c:1:19: error: stdio.h: No such file or directory
hello.c: In function 'main':
hello.c:5: warning: incompatible implicit declaration of built-in function 'printf'
so I tried a couple of other variants:
Code:
$ $HOME/src/mydroid/prebuilt/linux-x86/toolchain/arm-eabi-4.4.0/bin/arm-eabi-gcc -static -I $HOME/src/mydroid/bionic/libc/include -o hello hello.c
$ $HOME/src/mydroid/prebuilt/linux-x86/toolchain/arm-eabi-4.4.0/bin/arm-eabi-gcc -static -I $HOME/src/mydroid/ndk/build/platforms/android-8/arch-x86/usr/include/ -o hello hello.c
but they both give (different) errors about what other include files are missing when referenced from somewhere.
Is there some "easy" way to android-ify a source tree, so that I can build sources using the cross compiler toolchains? Or should I fetch a different cross compiler toolchain to use, like benno did in his document from 2007? He uses a codesourcery toolchain and builds with that instead (as referenced in other articles here on the subject).
Would much appreciate any shared tips or experiences on how to accomplish this.
The tool chain is fine the problem is non of the include/lib are set up correctly to find the needed version of the includes. Remember the default includes under linux depend on glibc and android only supplies bionic.
Have a look here for more info on setting up bionic:
http://android-dls.com/wiki/index.php?title=Compiling_for_Android
Though if you get the full source for glibc (or precompiled arm binaries) you could compile a dependant program staticly (I think that's what busybox does)
Building for older versions of Android
I was actually able to compile a program manually today, specifically one of the programs in the mtd-utils package. After lots of jumping back and forth, I have found out that the 64 bit version of Ubuntu is what I needed, and also sun-java-1.6, contrary to almost all information I found out there. Then I was able to build AOSP, and then I was able to get "agcc" working, the wrapper that sets environment variables automatically as needed.
So I compiled the app, but it didn't work on my Android. Trying to run it in an adb shell gave approximately this error (from memory):
/bin/sh: ./program: No such file or directory
though the program was there. I didn't use strace, but concluded that this is because of a missing shared library. I have a very recent version of AOSP, while the phone is running Android 2.0 or something like that, so that's a plausable reason why this is happening.
I tried to rebuild the program using "agcc -static ...", but that doesn't work because I don't have the static version of libc after building AOSP, so it just dies with a linker error complaining that it can't find -lc.
So now I need to figure out how to build for old Android version using my checked out version of AOSP, or I need to figure out how to check out an old version of AOSP using repo.
Any tips would be much appreciated.

[TUTORIAL/DEV]Build AOSP Android 2.3.7 for Allwinner A10 tablets (Teclast P76Ti)

Hi!
I haven't really found any kind of guides on how to build a complete AOSP android build from source (kernel and software) for Allwinner A10 tablets like the Ainol Novo 7 Advanced or the Teclast P76Ti.
I have a Teclast P76TI (rev4), and the following guide is only tested on such a device. As it's mostly based on the source drop of the Ainol Novo 7 Advanced, it should also work on that too.
Part 1
Part 1: Preparations
A: Preconditions
For building and creating a LiveSuite flashable package you will need the following:
For building the kernel and android you will need a 64 bit Linux machine. Ubuntu 10.04 64 bit is preferred for Gingerbread builds
For creating the LiveSuite flashable images, and actually flashing you will need a Windows machine. Windows 7 x64 works fine, as should Windows XP 32 bit too.
You will also need a working LiveSuite image file, for your tablet. Make sure that you can flash it to your device without problems!
Virtual machines are fine, if you have enough memory available. To build Android in a VM, you should give it at least 2GB of RAM. Alternatively if you're using Linux, you can create a Windows VM for the image creation or flashing part.
For the rest of the tutorial I will assume you are using a Linux Virtual Machine on a Windows box.
For building the kernel and AOSP you will need at least 35GB of free space in your linux machine (the more the better). To create the images you will need an additional 2GB of space on your Windows machine.
B: Getting the kernel and AOSP sources
First initialize your Linux machine according to this page: http://source.android.com/source/initializing.html
Here are the most important commands:
Code:
$ sudo add-apt-repository "deb http://archive.canonical.com/ lucid partner"
$ sudo apt-get update
$ sudo apt-get install sun-java6-jdk
$ sudo apt-get install git-core gnupg flex bison gperf build-essential \
zip curl zlib1g-dev libc6-dev lib32ncurses5-dev ia32-libs \
x11proto-core-dev libx11-dev lib32readline5-dev lib32z-dev \
libgl1-mesa-dev g++-multilib mingw32 tofrodos python-markdown \
libxml2-utils xsltproc
$ mkdir ~/bin
$ PATH=~/bin:$PATH
$ curl https://dl-ssl.google.com/dl/googlesource/git-repo/repo > ~/bin/repo
$ chmod a+x ~/bin/repo
// Additonal commands for Ubuntu 10.10:
$ sudo ln -s /usr/lib32/mesa/libGL.so.1 /usr/lib32/mesa/libGL.so
// Additonal commands for Ubuntu 11.10:
$ sudo apt-get install libx11-dev:i386
Now create a directory on your linux machine. The path should contain no spaces in it. Inside this directory first pull the kernel source from the allwinner github page:
Code:
$ git clone https://github.com/allwinner/linux-2.6.36 lichee
Make sure that the kernel resides in the lichee directory
Now download AOSP Android. We will use Gingerbread version 2.3.7:
Code:
$ mkdir android
$ cd android
$ repo init -u https://android.googlesource.com/platform/manifest -b android-2.3.7_r1
$ repo sync
Allwinner uses a special init, which has a few additional commands that you have to download too:
Code:
$ cd system/core
$ git pull git://github.com/sztupy/allwinner_android_system_core.git
$ cd ../..
You will also need the device descriptors for the tablets:
Code:
$ cd device
$ git clone git://github.com/sztupy/android_device_softwinner.git softwinner
$ cd ..
C: ARM compiler
You might simply use a compiler that is supplied for AOSP, they are inside the android/prebuilt/linux-x86/toolchain/arm-eabi-4.4.3/ directory. Alternatively you can also download the ARM compiler of CodeSourcery. Get the arm-2009q3 / arm-none-linux-gnueabi version, and unpack it inside a directory.
If ready, go on to next step: building the kernel
Part 2: Building the kernel
Change to the directory of the kernel. Now edit the file scripts/build_sun4i_crane.sh
Change the line "export CROSS_COMPILE=" to point to the ARM compiler. For example if you extracted the CodeSourcery files to /opt then use:
Code:
export CROSS_COMPILE=/opt/arm-2009q3/bin/arm-none-linux-gnueabi-
The default .config file is more or less the same that is supplied with your tablet. On the Teclast P76TI you can actually extract the .config file used from /proc using "adb pull /proc/config.gz" Not sure about other vendors.
Now you have to compile. Issue the command:
Code:
./build.sh -p sun4i_crane
This will build the kernel and modules inside the the "output" directory.
Next step is to compile Android
Part3
Part 3: Building Android
Go to the android directory. Now setup android using:
Code:
$ source build/envsetup.sh
$ lunch
You will get simething like this:
Code:
You're building on Linux
Lunch menu... pick a combo:
1. generic-eng
2. simulator
3. full_passion-userdebug
4. full_crespo4g-userdebug
5. full_crespo-userdebug
6. crane_Ainol_Novo7A-eng
7. crane_Teclast_P76TI_REV4-eng
Which would you like? [generic-eng]
Here select your device (option 6 or 7 depending on your tablet)
After you have selected it issue a make command:
Code:
$ make
This will take a while. If you're using ubuntu 11.10 make might fail, but you can fix it using these fixes: http://groups.google.com/group/android-building/browse_thread/thread/3484e7797909d014
After the building is complete you have to create the image files. Run the following command:
Code:
$ ./device/softwinner/crane-tcp76ti_r4/mkfs.sh
(substitute tcp76ti_r4 with ainovo7a if you're using the other tablet)
The image files will be ready in the directory "out/target/product/crane-tcp76ti_r4/images/" or "out/target/product/crane-ainovo7a/images/"
Copy the three files from here (root.img, recovery.img, system.img), and the "bImage" file from the "output" directory of the kernel to your Windows machine.
The next step is creating the flashable image, and flashing your build
Part 4: Flashing
A: Initialize kitchen
First download my A10 flash kitchen from this site: http://android.sztupy.hu/dl/a10/a10_flash_kitchen_v1.zip
This is based on the ainol novo 7 soruce drop, but only contains the nescessary files, and has a few batch scripts to automate the process.
There is also a v2, wich also supports ICS firmwares: http://android.sztupy.hu/dl/a10/a10_flash_kitchen_v2.zip
First unzip the files to a directory. You will see a few directories and to commands here: extract_image.bat and create_image.bat
First we have to extract an official image for your tablet. Simply comply the image file to this directory, and rename it to "original.img". If done, run extract_image.bat. This command should extract your image to the _extract directory.
Next you need to extract the bootfs inside the _bootfs directory. You have multiple options on how to do this:
1. Get the bootfs from your device on-line using adb:
Code:
> cd _bootfs
> adb shell
$ cd /
$ mount -o remount,rw -t ext4 /dev/root /
$ mkdir bootfs
$ mount -t vfat /dev/block/nanda /bootfs
(Control-C: exit adb shell)
> adb pull /bootfs
2. Get the bootfs from the extracted image file using Linux:
A. Copy the RFSFAT16_BOOTFS_000000000.fex file to linux
B.
Code:
$ mkdir bootfs
$ sudo mount -o loop RFSFAT16_BOOTFS_000000000.fex bootfs
$ cp -a bootfs b2
$ sudo umount bootfs
C. Copy the contents of the b2 directory to Windows, inside the _bootfs directory of the kitchen
B: Create image
If you have initialized the kitchen, you have to copy the four files from linux (system.img, root.img, recovery.img and bImage) inside the _input directory. You will also need to rename the .img files to .fex (so they should be system.fex, root.fex, recovery.fex).
If you are done with this, then run create_image.bat. It will create an output.img file, that can be flashed to the device using LiveSuite.
Additional information for developers:
1. Difference between AOSP 2.3.4 and Novo7 android 2.3.4
Download the diff file from here: http://android.sztupy.hu/dl/a10/diff_ainovo_aosp.gz
Filelist of differences: http://android.sztupy.hu/dl/a10/diff_ainovo_aosp_filelist.txt
sztupy, did you figure out why eDragonEx and FSBuild have an apparently unused Lua library next to each? I was interested by it, as it might be possible that some parts of the apps are actually written in Lua (would it be possible? Lua in a native DLL?), what would help reversing it.
fonix232 said:
sztupy, did you figure out why eDragonEx and FSBuild have an apparently unused Lua library next to each? I was interested by it, as it might be possible that some parts of the apps are actually written in Lua (would it be possible? Lua in a native DLL?), what would help reversing it.
Click to expand...
Click to collapse
Yeah, saw that. Also their build script used "convert" on the image.cfg, but that file wasn't in lua anyway (except for the image parts part which seems to be a lua hash).
There are also a lot of compiled files that are compiled inside the image file and which are neither the bootfs nor android or the kernel. I don't yet know what they are for, but I think they are used by LiveSuite during the flashing.
sztupy said:
Yeah, saw that. Also their build script used "convert" on the image.cfg, but that file wasn't in lua anyway (except for the image parts part which seems to be a lua hash).
There are also a lot of compiled files that are compiled inside the image file and which are neither the bootfs nor android or the kernel. I don't yet know what they are for, but I think they are used by LiveSuite during the flashing.
Click to expand...
Click to collapse
I know most of the files from the flashing, they are the following:
- SYS_CONFIG is used as a command bunch for LiveSuite. It tells the app how to flash, what to flash, where, and it configures the device too (screen size, ram info, cpu info, etc)
- Boot0 and Boot1 bins are NAND bootloaders
- FED FES and FET tools are NAND flashing utilities, checksums, hardware scanner, and other tools used during flashing.
- '12345678' files are bootloaders, config files, and tools for SDMMC flashing, if there's a device with SDMMC internal instead of NAND, these are used
- Split seems to be some kind of ID string, I had no luck retrieving it's usage and meaning.
So you say, that the actual Lua parts are the image encryption parts of eDragonEx? Interesting, maybe I've missed that spot with my tool...
Might I ask if you have tried disassembling (and decompiling) unimg.exe? I had several problems with it, but that would greatly help understanding how the images are created. I've got a C# framework, with image config parser, etcetera etcetera, to be able to read and create images in a much more advanced environment (filtering user errors, having tools for everything (bootfs modding, script.bin reversal, etcetera), and creating a working image as a final result), and it only needs the image file format (and some of my work, to create a parser).
The problems with unimg were all about positive sp values, and as I'm not a big assembly programmer, I couldn't make out anything from that. Maybe you understand it a bit more
Illetve beszélhetünk egy kicsit magyarul is. Tabletrepublic-on írtam hogy vegyél fel MSNre és részletezem a különböző Crane SDK elemek funkcióit, működését, egyebeket, amit eddig sikerült kiderítenem az egészről.
Sajnos elég zavaros, mivel vagy négyféle csomagoló rendszer készíti a fileokat, és ezek közül csak egy működött rendesen (crane_pack.exe). Jó lenne megérteni ezt a file formátumot, hogy egy kicsit normálisabb módon hozhassam létre, különféle vacakolások nélkül.
fonix232 said:
I know most of the files from the flashing, they are the following:
- SYS_CONFIG is used as a command bunch for LiveSuite. It tells the app how to flash, what to flash, where, and it configures the device too (screen size, ram info, cpu info, etc)
- Boot0 and Boot1 bins are NAND bootloaders
- FED FES and FET tools are NAND flashing utilities, checksums, hardware scanner, and other tools used during flashing.
- '12345678' files are bootloaders, config files, and tools for SDMMC flashing, if there's a device with SDMMC internal instead of NAND, these are used
- Split seems to be some kind of ID string, I had no luck retrieving it's usage and meaning.
Click to expand...
Click to collapse
Thanks for these. Seems I was mostly right
So you say, that the actual Lua parts are the image encryption parts of eDragonEx? Interesting, maybe I've missed that spot with my tool...
Click to expand...
Click to collapse
I think lua is not really used anymore. It probably had more relevance back in the past.
Might I ask if you have tried disassembling (and decompiling) unimg.exe? I had several problems with it, but that would greatly help understanding how the images are created. I've got a C# framework, with image config parser, etcetera etcetera, to be able to read and create images in a much more advanced environment (filtering user errors, having tools for everything (bootfs modding, script.bin reversal, etcetera), and creating a working image as a final result), and it only needs the image file format (and some of my work, to create a parser).
The problems with unimg were all about positive sp values, and as I'm not a big assembly programmer, I couldn't make out anything from that. Maybe you understand it a bit more
Click to expand...
Click to collapse
No, haven't tried disassembling it yet. I was very glad that it worked, and that I could create a whole working build just from the sources. I know there are a lot of quirks, like if the extension of the file is not .fex, then it will encrypt(?) it, etc. I might try it, but currently I'm more interested in getting a working AOSP ICS on my tablet. Besides for disassembly I need to be in a special mood, which I'm not really in now
Illetve beszélhetünk egy kicsit magyarul is. Tabletrepublic-on írtam hogy vegyél fel MSNre és részletezem a különböző Crane SDK elemek funkcióit, működését, egyebeket, amit eddig sikerült kiderítenem az egészről.
Sajnos elég zavaros, mivel vagy négyféle csomagoló rendszer készíti a fileokat, és ezek közül csak egy működött rendesen (crane_pack.exe). Jó lenne megérteni ezt a file formátumot, hogy egy kicsit normálisabb módon hozhassam létre, különféle vacakolások nélkül.
Click to expand...
Click to collapse
Már egy jó ideje nem használok MSN-t. Skype/GTalk/email viszont van. Ha nem használsz olyanokat, akkor azért majd felrakom.
Made a diff between AOSP android 2.3.4 and the Novo 7 2.3.4 source drop. The list can be found at post 6: http://forum.xda-developers.com/showpost.php?p=22397984&postcount=6
Nice tutorial! Do you mind if I fork your Github repo and add the device tree for the Bmorn V11 to the lunch list?
sztupy said:
Made a diff between AOSP android 2.3.4 and the Novo 7 2.3.4 source drop. The list can be found at post 6: http://forum.xda-developers.com/showpost.php?p=22397984&postcount=6
Click to expand...
Click to collapse
Most of the things changed aren't even needed for the device - ril can be replaced with a local one (and suggested by Google to do so), just like recovery changes, in ICS we already have USB BT support enabler, so BT changes can be dropped, just like framework changes (they are for the softbuttons on the notification bar), camera and mediaplayer changes should be local too (in the device tree), so 99% of changes can be dropped.
Additions are different, some can be totally erased, and some are needed. From your github, I see that you've already began making a cleaned up, generic A10 tree, but I miss a few things - libsensor for one, stagefright, camera, and audio. The AOSP stock ALSA should work, if the proper audio config is placed in a ROM, but I have bad feelings about the missing libsensors source, and camera. Stagefright has a chance too to work, but camera definitely won't, and the used sensors aren't the common ones to be included.
Használok GTalk-ot is, ott is ugyanez a nicknevem, gmail utótaggal, szóval a szokásos
FezzFest said:
Nice tutorial! Do you mind if I fork your Github repo and add the device tree for the Bmorn V11 to the lunch list?
Click to expand...
Click to collapse
That's what github is for
fonix232 said:
Most of the things changed aren't even needed for the device - ril can be replaced with a local one (and suggested by Google to do so), just like recovery changes, in ICS we already have USB BT support enabler, so BT changes can be dropped, just like framework changes (they are for the softbuttons on the notification bar), camera and mediaplayer changes should be local too (in the device tree), so 99% of changes can be dropped.
Additions are different, some can be totally erased, and some are needed. From your github, I see that you've already began making a cleaned up, generic A10 tree, but I miss a few things - libsensor for one, stagefright, camera, and audio. The AOSP stock ALSA should work, if the proper audio config is placed in a ROM, but I have bad feelings about the missing libsensors source, and camera. Stagefright has a chance too to work, but camera definitely won't, and the used sensors aren't the common ones to be included.
Használok GTalk-ot is, ott is ugyanez a nicknevem, gmail utótaggal, szóval a szokásos
Click to expand...
Click to collapse
libsensor and stagefright are still there, as I could manage them to get compiled. Not that they work though. For the libcamera it depends on CedarX, which I couldn't manage to compile, that's why I removed it (for now). Besides CedarX unfortunately not "open-source", so in theory we couldn't use it either (well... not that I actually care about licence violations).
I'm still compiling ICS. Will put back libcamera and try to get the other hardware libs to work after I managed to get ICS to boot.
sztupy said:
libsensor and stagefright are still there, as I could manage them to get compiled. Not that they work though. For the libcamera it depends on CedarX, which I couldn't manage to compile, that's why I removed it (for now). Besides CedarX unfortunately not "open-source", so in theory we couldn't use it either (well... not that I actually care about licence violations).
I'm still compiling ICS. Will put back libcamera and try to get the other hardware libs to work after I managed to get ICS to boot.
Click to expand...
Click to collapse
Please be noted that ICS requires new stagefright, camera HAL, new GPU drivers, and so on.
ICS also should have some differences in the build tree, make a new branch for sure (as an example, it requires a device.mk and device_base.mk, both being the base containers without target definition, full_[devicename].mk for the actual full target, and cm.mk for CyanogenMod, what I'd suggest you to build).
I couldn't find any of the sources, but must have overlooked something. Will check it further.
hi, I'm the author of unimg(esxgx).
and your unimg is not up-to-date(the version still have bugs to lead to fail the packing process.
Here is the latest version (fix bugs but no virus alarm[compared with the former version]), and you can use it in the same way.
please update your file.
PS. yes, the unimg can unpack and pack all allwinner's firewares without diffculty, good luck.
sorry for my english.
fonix232 said:
Might I ask if you have tried disassembling (and decompiling) unimg.exe? I had several problems with it, but that would greatly help understanding how the images are created. I've got a C# framework, with image config parser, etcetera etcetera, to be able to read and create images in a much more advanced environment (filtering user errors, having tools for everything (bootfs modding, script.bin reversal, etcetera), and creating a working image as a final result), and it only needs the image file format (and some of my work, to create a parser).
The problems with unimg were all about positive sp values, and as I'm not a big assembly programmer, I couldn't make out anything from that. Maybe you understand it a bit more
Click to expand...
Click to collapse
I think you should use unimg.exe.
unimg is the only tool to unpack it correctly.
you know, allwinner didn't want me to release the tool in public last year(the tool is for sc9800[the former chip]). for some commercial reason, the offical toolchain of a10 only contains pack_tool.
so I released the tool with other tools(rootcr, rootpk,etc..) in a small group.
but some person posted it on the internet. so....
I developed the analysis tools in the form of many files(unimg, rootcr, rootpk, unimg2), because I want to keep each of the packing stages simple.
you can use a "bat" file / a GUI shell to communicate with each other, and that is what I expected.
I can't smoothly speak english, so I modified several times.
Thank you very much!
If I may ask, would it be possible to release the source code too?
fonix232 said:
Thank you very much!
If I may ask, would it be possible to release the source code too?
Click to expand...
Click to collapse
I cannot released yet, but I will release it in a proper time on github (I have been touching with allwinner company, so I have to consider many factors).

[GUIDE] How to Build and Package a Kernel [D2]

This thread aims to be a comprehensive guide to building and packaging kernels for US Variant Samsung Galaxy SIIIs
In my opinion, a kernel is a great way to get into building things for your device and its pretty easy to do too.
Intro
What is a kernel?
http://en.wikipedia.org/wiki/Kernel_(computing)
This guide is for US SGSIII's (d2att,d2cri,d2mtr,d2spr,d2tmo,d2usc,d2vzw,others?)
It may be possible to adapt this to other devices, but I am not responsible for anything that happens should you try to do this.
This guide assumes you have a general knowledge of the Linux operating system. If you've never used it, you might consider playing around
with it for awhile before attempting this guide.
Click to expand...
Click to collapse
Prerequisites
On all devices you must be rooted, on Verizon SGS3 (d2vzw) you must also have the unlocked (VRALE6) bootloader installed.
This is not the thread for figuring out how to do this. You can use the forum's search function to figure out how to do this on your device.
You'll need a computer or a virtual machine running ubuntu. You may be able to figure out how to get this working on other distributions,
but since ubuntu is generally the most accepted distribution to use for building android things, I'll stick to using that here.
At the time of this writing, I'm using ubuntu 12.10, 64-bit.
You'll need to install some packages on your ubuntu machine:
Code:
sudo apt-get install build-essential git zip unzip
On 64-bit you'll also need some multilib and 32-bit compatibility packages:
Code:
sudo apt-get install gcc-multilib g++-multilib lib32z1-dev
Click to expand...
Click to collapse
Setting up the Build Environment
Next, you'll need a toolchain which is used to actually build the kernel. You may download one of these:
GCC 4.4.3: Download || Mirror
GCC 4.6: Download || Mirror
GCC 4.7: Download || Mirror
If you aren't sure, go for 4.4.3 or 4.6.
4.7 requires some code changes to work. The original kernel developer may or may not have made these changes.
Here is what I needed to do in order for 4.7 to build, boot and have wifi work:
https://github.com/invisiblek/linux-msm-d2/commit/f8d7199d37cfbfa1bcb6b4bcae3fc15ae71fbdea
https://github.com/invisiblek/linux-msm-d2/commit/ea58076501e5874db7b934c215c4dae81ddfd0a6
The toolchains are also available in the android NDK.
*** There are many toolchains out there, some of you may know of the Linaro toolchain which is aimed to optimize your binary even further ***
*** If you choose to use a different toolchain, that is fine. Keep in mind that you may run into issues depending on the toolchain you use ***
You can check what your currently running kernel was built with by issuing these commands:
Code:
adb root
adb shell cat /proc/version
It should return something like:
Linux version 3.4.0-cyanogenmod-gc4f332c-00230-g93fb4aa-dirty ([email protected]) (gcc version 4.7 (GCC) ) #134 SMP PREEMPT Thu Feb 28 00:22:41 CST 2013
Click to expand...
Click to collapse
This shows my particular kernel here was built with GCC 4.7
You can use wget to download one of the links from above, in this instance we'll download version 4.4.3 from the first link:
Code:
wget http://invisiblek.org/arm-eabi-4.4.3.tar.bz2
Extract this to somewhere you will remember, probably your home directory.
Code:
mkdir arm-eabi-4.4.3
tar -xf arm-eabi-4.4.3.tar.bz2 -C arm-eabi-4.4.3/
Click to expand...
Click to collapse
Obtaining Source
Find someone's source to use as a base. This can be a source archive from Samsung, a kernel tree from CyanogenMod, or any other developer around that makes kernels for your device.
TIMEOUT
This is a good spot to stop and take note that the Linux kernel is licensed under the GNU General Public License (GPL): http://www.gnu.org/licenses/gpl-2.0.html
What does this mean you ask? It means that if you plan to share your kernel with the community (if it's good, please do so!) then you MUST share your
source code as well. I am not liable for what you choose to do once you start building kernels, but know this: if you share your kernel and do not
provide source code for it, you will get warnings from XDA for a determined amount of time, after that you may have your threads closed, deleted and
possibly your user account terminated. This is extremely important!
Also, you may run into more problems than just XDA. There are organizations out there that do take action if you consistently refuse to comply with the GPL.
I recommend you read this: http://www.gnu.org/licenses/gpl-2.0.html so that you are familiar with what legalities you are getting yourself into.
The main thing to remember is to share your source code if you decide to share your built kernel.
Click to expand...
Click to collapse
In this instance, we will use CyanogenMod's kernel source for the US Galaxy S3's. You may browse the source code here:
https://github.com/CyanogenMod/android_kernel_samsung_d2
You'll notice that the branch there is cm-10.1
This is the default branch of this repository on github. This means that if you intend to build this branch, you'll need to use it on CM version 10.1. Most
likely it will not function on another version.
To obtain the source code:
Code:
git clone https://github.com/CyanogenMod/android_kernel_samsung_d2
This will take a little while, be patient.
When done, you'll have a directory called android_kernel_samsung_d2, cd into this directory.
Code:
cd android_kernel_samsung_d2
Next, you'll need to set up a couple environment variables. These tell the system two things:
1. What CPU architecture to build for, in this case arm
2. Where to find the toolchain we downloaded earlier, so that the system can cross compile for arm
Code:
export ARCH=arm
export CROSS_COMPILE=~/arm-eabi-4.4.3/bin/arm-eabi-
You'll need to set these variables on each new session. You can modify your Makefile in the root of your kernel tree in order to have these set permanently.
Click to expand...
Click to collapse
Building
At this point you can make any changes to the source code that you want. If this is your first time, I recommend not making any changes and make sure you have a
sane build environment before adding any complications.
When you build a kernel, you need to choose a defconfig. This is a specialized configuration file, specifically tailored for your device.
CyanogenMod names their defconfigs for their devices like so: cyanogen_<device>_defconfig and they are located in arch/arm/configs/
Code:
ls arch/arm/configs/cyanogen*
In this example, we will build for d2vzw.
Set up your tree to build for the d2vzw:
Code:
make cyanogen_d2vzw_defconfig
(do this in your kernel's root directory, in this example it was android_kernel_samsung_d2/ )
Now you are ready to build:
First, determine how many cpu's your computer has. You'll use this number to determine how many jobs the compiler command will use. The more jobs you can use, the more
cpu threads the compile will take advantage of, thus you'll get faster builds. If you don't know, just assume you'll use the number 2. We'll use 2 as an example here.
Code:
make -j2
Where 2 is the number of CPU cores your build system has.
And now we wait...until it's done compiling...
You'll know it successfully compiled when you have this line when it stops:
Kernel: arch/arm/boot/zImage is ready
Click to expand...
Click to collapse
PROTIP:
If it stops somewhere other than "zImage is ready" then you had build errors. Try running the 'make' command with no options after it. This will run the compile on a single thread
and will cause it to stop compiling as soon as it hits an error. When you run it on multiple threads, it definitely goes much faster, but if an error occurs, the console doesn't stop
until it finishes all of its threads. Causing you to have to scroll up and search around for an error
Click to expand...
Click to collapse
Now, assuming the build completed successfully, you have two things you are concerned with: A zImage (the kernel binary itself) and your kernel modules, which get built based
on what was configured in your defconfig.
You'll find your zImage at: arch/arm/boot/zImage
Code:
ls arch/arm/boot/zImage
The modules are scattered all over the place, depending on where the source existed that they were compiled from. We can easily search for them using this command:
Code:
find . -name "*.ko"
If both of the previous commands completed, you are now ready to package your kernel up for testing.
Move up a directory before continuing.
Code:
cd ..
Click to expand...
Click to collapse
Packaging
You may know of an awesome developer by the name of koush.
Well, once upon a time, koush created a rather simple zip, called AnyKernel, that would flash a kernel on a device, regardless of what ramdisk the kernel has on it.
I've taken his zip and modified it for d2 devices and to work with the newer recoveries out there.
This has a script in it that will dump your current boot.img (kernel+ramdisk), unpack it, replace the kernel, repack it and flash it.
It'll also copy any modules to the proper directory (/system/lib/modules) and set permissions appropriately.
You can get a zip here: Download || Mirror
(You can get it here as well: https://github.com/invisiblek/AnyKernel )
(Everyone is invited to use this zip, it'll probably make your life easier to not have to worry about the ramdisk. Enjoy!)
IMPORTANT
This AnyKernel package is for US variations of the Galaxy S3.
NOT the international (I9300) or any other device.
There are checks in the updater-script that will ensure you are running a d2 device before it does anything.
If you were to remove these checks, and not modify the partition that it flashes to later, you could end up with a brick.
If you intend to adapt this package for another device (please, do this! its a very handy script!), make sure you know it well, or ask someone to help you determine your device's
partition scheme before using it.
The risk here is due to the fact that the script doesn't know your device's partition scheme. It is configured specifically for the d2 devices. Flashing it on something else, who's boot
partition is somewhere else, might cause a bad flash to the bootloader partition (bad bad news if this happens).
Just be careful if you want to use this on another device. You won't run into problems if you use this on a d2 device.
EDIT: I made modifications that should make this less likely, but please, if you intend to use this on a different device (which is completely fine!) make sure you configure
the scripts to flash to the proper partitions.
Click to expand...
Click to collapse
Download and extract one of the above, we'll again use the first link for this example:
Code:
wget http://invisiblek.org/AnyKernel_samsung-d2.zip
unzip AnyKernel_samsung-d2.zip -d AnyKernel/
Now we'll copy our newly compiled zImage (still referring to the same kernel directory we used above, your repo might be called something different)
Code:
cp android_kernel_samsung_d2/arch/arm/boot/zImage AnyKernel/kernel/
cp `find android_kernel_samsung_d2 -name "*.ko"` AnyKernel/modules/
Finally we are ready to zip this up and test out flashing it.
Code:
cd AnyKernel
zip ../MyAwesomeKernel.zip -r *
cd ..
You'll now have a file named MyAwesomeKernel.zip which you should be able to flash via custom recovery (TWRP or CWM)
Click to expand...
Click to collapse
Extra Credit/Protips
Learn to use git. It's very powerful and great way to store your code.
Learn to use adb. It's an invaluable tool for any android developer.
Touchwiz and AOSP-based kernels are different. This means you cannot take CyanogenMod's source, build a kernel and expect it to work on a Touchwiz-based ROM.
Build a ROM next: http://wiki.cyanogenmod.org/w/Build_for_d2vzw
Crackflash your own stuff!
ALWAYS NANDROID!
Click to expand...
Click to collapse
Source code for all of my projects can be found here: http://github.com/invisiblek
FAQ
Q: How do I update my source tree to the latest that is available from where I downloaded it?
A: This can be handy if, for instance, you are building a CyanogenMod kernel and they added some patches, after you downloaded the source, that you want to include in your next build. You'll want to cd to your kernel tree and issue a git pull:
Code:
cd android_kernel_samsung_d2
git pull
You may then continue with the building instructions.
This may, however, have other problems if you've made changes to files. You might run into conflicts. I won't cover fixing any of this here, its not in the scope of this thread.
Q: I'm using X as a kernel base, but Y has a patch that I really like. How do I get it in my kernel easily?
A: I'll let you check Google for this answer, but I'll give you a hint use: git cherry-pick
Nice tutorial bro! Always good to learn something new everyday
Really is a good thread,thanks
This guide would have made things too easy for me.
Too easy, indeed. haha
Great job, invisiblek! AnyKernel is the beez neez.
Ok so this is a noob question but I gotta ask anyway lol. Ok so I cloned the kernel source, I made my edits, now how do I push all this to my github?
I already have a github account, I already made a new repo for the kernel. Here's a link to my github if you need it...
https://github.com/ghicks12/d2vzw_kernel.git
spc_hicks09 said:
Ok so this is a noob question but I gotta ask anyway lol. Ok so I cloned the kernel source, I made my edits, now how do I push all this to my github?
I already have a github account, I already made a new repo for the kernel. Here's a link to my github if you need it...
https://github.com/ghicks12/d2vzw_kernel.git
Click to expand...
Click to collapse
git remote add origin git_location_you_created_on_github.git
git push -u origin somebranch
The -u is for first time run only, you can just git push afterwards.
Sent from my SCH-I535
GideonX said:
git remote add origin git_location_you_created_on_github.git
git push -u origin somebranch
The -u is for first time run only, you can just git push afterwards.
Sent from my SCH-I535
Click to expand...
Click to collapse
Thanks! When I run
Code:
git remote add origin https://github.com/ghicks12/d2vzw_kernel.git
I get this back:
Code:
fatal: remote origin already exists.
I'm editing a CM based kernel, not sure if that matters or not?
That just means you added the remote already. Just issue the push command then.
Sent from my SCH-I535
Why is this happening? I don't know what i did wrong
[email protected]:~/cm$ make VARIANT_DEFCONFIG=cyanogen_d2att_defconfig
scripts/kconfig/conf --silentoldconfig Kconfig
drivers/media/video/msm/Kconfig:123:warning: choice value used outside its choice group
drivers/media/video/msm/Kconfig:128:warning: choice value used outside its choice group
***
*** Configuration file ".config" not found!
***
*** Please run some configurator (e.g. "make oldconfig" or
*** "make menuconfig" or "make xconfig").
***
make[2]: *** [silentoldconfig] Error 1
make[1]: *** [silentoldconfig] Error 2
make: *** No rule to make target `include/config/auto.conf', needed by `include/config/kernel.release'. Stop.
[email protected]:~/cm$
Hey. I'm having some problems with some GIT terminology and procedures. I'm a .NET developer and I use TFS and SVN on a daily basis. Forgive me if this is complete off basis from what you'd do with GIT.
What I want to do is merge one branch into another branch. In other words I want to take the latest kernel source from my favorite dev and merge in the latest from cyanogen's 4.3 d2 branch. Is this a rebase thing? It doesn't seem like cherrypicking to me.
I have successfully compiled kernel and made modules.I inserted zImage and modules inside any kernel updater,flashed via TWRP.When reboot stuck in odin and it says could not do normal boot.

[GUIDE] [BIN] Compile busybox on Linux

About Busybox: busybox.net/about.html
More on Busybox: busybox.net
This is just for anyone who wants to try, and especially those without access to a PC.
:
: --------------- BUILD STEPS --------------
:
Things we'll need besides your phone:
- "Android Terminal Emulator" app
- "Complete Linux Installer" app , I also recommend trying "linux deploy" for more advanced usage
- internet/wifi
- latest "busybox" source
1) We need to get Ubuntu or Debian booted for a sufficient build environment (kali linux works well too). I've used them all on Android but I like the better stocked terminal in the Ubuntu images. I used the app "Complete Linux Installer" which is free and works beautifully, very simple and easy. In the app you want to follow the short instructions to download an Ubuntu image, rename it to ubuntu.img, and place it in a folder named ubuntu in /sdcard. Then hit menu in the app and click the terminal screen icon that says "Launch". An Ubuntu terminal will now open in Android Terminal Emulator. Super quick and easy.
2) Let's download some crucial build environment tools.
Code:
apt-get install -y gcc build-essential libncurses5-dev libpam0g-dev libsepol1-dev libselinux1-dev
--EDIT-(30AUG2014)--
For Selinux compatibility and loginutils, we need to also download a few extra packages. Already included in the code above.
3) Now the cool thing about this chroot Ubuntu environment is that we still have access to the sdcard to transfer files between Android environment and the chroot jail. Extract your downloaded busybox source to your Ubuntu home with something like:
Code:
cd
tar -xf /sdcard/Download/busybox*bz2
cd busybox*
4) Now we can build busybox statically. The first thing we do is generate a Makefile by running "make" with a "defconfig" (default configuration file) Usually you will run "./configure" with other programs, but busybox compiles more like a kernel, so it uses a config which has a huge checklist of options.
(After successfully compiling busybox, we can go back and customize the .config; this entails that for each "CONFIG ..." line we see, we can uncomment it and mark it "y" or "n" to configure some option... This can be more easily done from a terminal busybox menu interface with "make menuconfig". You just need to crank font down to 7 or use telnet/ssh)
Skip "make defconfig" if you use a customized ".config" file such as one I've attached.
Code:
make defconfig
If all goes well, we now have a Makefile and are ready to compile:
Code:
make clean && make LDFLAGS=-static
Let "make" crank out the binary for a couple minutes. The extra variable we set after make is to compile statically. When compiling is complete we'll have a few different busybox binaries at the root of the source directory. We use the one named "busybox" since we're not debugging.
5) Now let's copy it to /system/usr/bin to install for test usage.
Code:
cp ./busybox /android/data/media/0
(Open a new terminal tab to get into Android Environment)
mount -o remount,rw /system
mkdir -p /system/usr/bin
cp -f /sdcard/busybox /system/usr/bin
chmod 0555 /system/usr/bin/busybox
/system/usr/bin/busybox --install -s /system/usr/bin
mount -o remount,ro /system
PATH+=:/system/usr/bin
.. and done. Run some scripts and enjoy your static busybox!
:
: Extra steps for SELinux-enabled busybox
:
Here are the extra steps you need to take to compile busybox with SELinux features. Sorry it took so long to get this added to this first post.
First we need to download the source for libselinux and libsepol and compile it. (This is for use with the standard glibc toolchain.)
Code:
cd
apt-get source libselinux libsepol
cd libselinux*
make
cd
cd libsepol*
make
Now that we have those libraries compiled, we can proceed to the busybox compilation.
Code:
cd
cd busybox*
make clean && make LDFLAGS='-static -L ../libselinux*/src -L ../libsepol*/src' CFLAGS='-Os -I ../libselinux*/include -I ../libsepol*/include'
That's pretty much it. It initially seems more complicated than it actually is, but all we're really doing is including the libraries for libselinux and libsepol into the busybox compilation.
edit:
**Commands to run if you have compile errors:
Code:
apt-get build-dep busybox
apt-get install -y build-essential
apt-get -f update
dpkg --configure -a
:
: --------------- DOWNLOADS --------------
:
***** Attached are flash installers for busybox (v1.23.1 stable, non-SELinux, 374 applets included!, ~1.1MB size) or busybox (v1.23.1 stable, SELinux, 386 applets included!, ~1.6MB size) *****
Since it's up-to-date it has some nice extras most people haven't seen like a "-I" option for xargs! Yes, that is correct, busybox xargs has its testicles back.
Code:
e.g.
$ echo Hello | xargs -I{} echo {} world!
> Hello world!
: ---------- UPDATES ----------
-------------------EDIT-2-(30AUG2014)----------------------
Got a Selinux-enabled busybox attached now. This means Selinux flags are integrated into applets like ls, id, ps, etc, and there are now 12 extra Selinux applets to give a total of 386 applets, ~1.6MB in size. The previous one is more portable, but this one can completely replace toolbox and gives you Selinux control for Android 4.4+. Plus it's pure maxed-out awesomeness.
***I've also attached the .config files for each busybox I've compiled, so anybody can remake them (from their phone!) as I've posted. You just need to download and extract the .config file to the root of your busybox source directory and type "make".***
-------------------EDIT-3----------------------
YashdSaraf has made some very useful flash zips to install either the non-selinux- or selinux-enabled busybox 1.23.1 via recovery. Installation replaces the stock busybox in /system/xbin. I've attached the zips he made to the end of this OP.
(**Note: Thought I'd mention that there will be a handful of applets that don't work in "Android" environment such as su(don't worry this isn't linked with the installer) Part of this is because of the way Android's default file structure is an amputated modified version of linux. With almost all of them, slight modifications to environment and file structure can be made to get them to work. This is just normal behaviour of busybox in android. The su and init applets shouldn't be used in Android though. I keep them compiled into the binary anyway for completeness of the build and because they work and are needed for a root.gz initrd or some chroot environments. It also doesn't hurt keeping them compiled in. You just have to remember not to link them when installing busybox.
-------------------EDIT-4-(06SEPT2014)----------------------
:
: How to compile against(using) uclibc for a smaller binary!!
:
Download the attached arm-linux-uclibcgnueabi toolchain package that I pre-compiled. Extract to /data/media:
Code:
cd /data/media
zip='/sdcard/Download/2014-09-06__arm-buildroot-linux-uclibcgnueabi.tar.lz.zip'
unzip -op "$zip" | lzip -d | tar -xf -
Then let's open up the "Complete Linux Installer" or "Linux Deploy" terminal.
To use the toolchain with a busybox build, we just need to specify the parameter CROSS_COMPILE which is a prefix to the compiler tools. So if you extracted the toolchain to /data/media, you will use:
Code:
make clean && make LDFLAGS=-static CROSS_COMPILE=/android/data/media/arm-buildroot-linux-uclibcgnueabi/bin/arm-buildroot-linux-uclibcgnueabi-
When you're done you should have a busybox binary with 374 functions with size around 1.1MB. That's a 20% decrease in size from using the standard glibc toolchain!
**IMPORTANT Notes
- The toolchain can't be used with lollipop since it's not compiled with -fPIC. I'll fix this later. Busybox is fine since it's static, it's just the toolchain I uploaded.
- Selinux-enabled busybox .config errors out when building using the uclibc toolchain; I think this is a lack of support issue. In the "Complete Linux Installer" app you'll need to add the mount "/data/media" in options. This gives you access to it as "/android/data/media", very very useful for extra space needs.
Difference between SELinux and non-SELinux busybox
The SELinux (NSA security enhanced Linux) binary comes with the following extra utilities: chcon, getenforce, getsebool, load_policy, matchpathcon, restorecon, runcon, selinuxenabled, setenforce, setfiles, setsebool, and sestatus. There are also some selinux flags enabled for applets such as "ps" and "ls", e.g. "ps -Z" and "ls -Z" to show the context for processes or files. If you are using Android 4.3 or newer, then you probably want to use the SELinux-enabled busybox since Android 4.3 is when SELinux was introduced to Android. Using the SELinux busybox on older version of Android without SELinux file structure should probably work besides the SELinux applets, but I haven't tested this. The non-SELinux binary can be used on any version of Android. When it comes down to it, the system actually uses "/system/bin/toolbox" SELinux applets for SELinux operations, so unless you specifically want to use busybox's SELinux tools for personal use, the safest option is to go with the non-SELinux busybox. I use Android 4.3.1 and 5.x, so I use busybox's better featured SELinux tools.
Latest updates see post 2
Busybox 1.23.1 (2015-02-06) below
Busybox compilation on Linux
reserved
Great Info here!
But I would be interested to know how well this method works on Samsung Stock devices running AOS 4.2 and above? Any experience?
Awesome info, this thread came up #1 while googling busybox 1.23
I made a flashable zip of the attached binary in the op to clean the old one(if any) and install the new busybox in xbin, just in case if anyone needs it. :good:
Is it work on xperia sp on 4.3 fw yes ?
YashdSaraf said:
Awesome info, this thread came up #1 while googling busybox 1.23
I made a flashable zip of the attached binary in the op to clean the old one(if any) and install the new busybox in xbin, just in case if anyone needs it. :good:
Click to expand...
Click to collapse
Thanx,worx fine with Carbon 4.4.4 on my LG.
GREETZ FROM TEAM-OPTIMA!!!
E:V:A said:
Great Info here!
But I would be interested to know how well this method works on Samsung Stock devices running AOS 4.2 and above? Any experience?
Click to expand...
Click to collapse
Thanks man. I've been compiling tons of stuff with Debian and Ubuntu chroot no problem on top of 4.3.1 Vanir and also 4.4.4 Carbon, both are my daily drivers. "Complete Linux Installer" is pretty fast compared to some other chroot apps like GNUroot (no offense to GNUroot, it works but is way too slow). It runs real-time compared to non-chroot. When compared to my dual-core 2007 Pentium M laptop, it's about 2-3 times as slow which isn't too bad for compiling something like mksh or even busybox which takes up to 5 mins I'd say.
In terms of binary size, compiling natively is better than cross-compiling it seems. I used gcc with no size optimizations here, so 1.37MB is pretty nice compared to some others around 2MB with full configs. With this method and klcc (gcc wrapper) I got mksh compiled to 192KB. I'm currently trying to build a uclibc toolchain on my laptop that will give me a mksh binary under 300KB..
YashdSaraf said:
Awesome info, this thread came up #1 while googling busybox 1.23
I made a flashable zip of the attached binary in the op to clean the old one(if any) and install the new busybox in xbin, just in case if anyone needs it. :good:
Click to expand...
Click to collapse
Cool thanks man! That is really useful, glad to hear from CALIBAN that it works. Could I add this to the OP with credit to you?
Hamidreza2010 said:
Is it work on xperia sp on 4.3 fw yes ?
Click to expand...
Click to collapse
Yes, xperia sp uses armv7 so you should be good to go.
7175 said:
Cool thanks man! That is really useful, glad to hear from CALIBAN that it works. Could I add this to the OP with credit to you?
Click to expand...
Click to collapse
Sure bro go ahead
Edit: Went ahead and made one for selinux enabled busybox :silly: , you can add this one in the op too.
Hey guys I was able to get an entire uClibc toolchain built the other day (using buildroot). I tested it and it makes some nice small binaries with about 20%+ smaller size than the standard glibc. Man that took hours to compile but was well worth it. It really put the stability of Android OS to the test as well. Kitkat absolutely couldn't finish compiling with multiple oom's and oops's, but Vanir 4.3.1 stuck it out real nice. Once I had the huge amount of required buildroot packages downloaded, I was able to compile in TWRP as well with good stability. (I have the "Complete Linux Installer" startup chroot script aliased in my mkshrc so I can pull up an ubuntu terminal without starting the app. )
So I got 3 new attachments to OP:
- arm-linux-uclibc toolchain for anyone who wants to compile stuff with it (host=arm AND target=arm)
- busybox (374 fcns, non-selinux) 1116KB
- lzip binary (in case you need it to unzip the toolchain, which is highly compressed from 64MB to 14MB with lzip's lzma)
**As I mentioned in the updated OP, I wasn't able to get selinux-enabled busybox compiled with uclibc. This may be something unsupported, or there may be a patch fix. I'll check it out. I'll try with musl libc and musl-gcc as well.
I have another approach, I try aboriginal cross compiler toolchain in archLinux it produced small binary, but I can't compile busybox for android. For Linux it work. Maybe need bionic lib?
ndrancs said:
I have another approach, I try aboriginal cross compiler toolchain in archLinux it produced small binary, but I can't compile busybox for android. For Linux it work. Maybe need bionic lib?
Click to expand...
Click to collapse
Sounds interesting. I honestly haven't given this a try yet, but I'm very interested in taking a look at it. At this point I'm pretty much addicted to making the smallest binaries I can and testing out different toolchains. I'll give it a good search on duckduckgo, and if you have any insightful links that would be great.
Edit: Alright cool I found the source for Aboriginal Linux at landley.net/aboriginal and am building on Android now. I'm also trying this on my x86_64 laptop so that I can compare the differences like I have with glibc, uclibc, musl, klibc binary builds in a native environment and a cross-compile environment.
I see from my laptop's build that a busybox was generated, but it was dynamic and has a libc.so.6 dependency. @ndrancs : this might be what you were talking about. Did you try compiling static? Also see if "make allnoconfig && make clean && make LDFLAGS=-static" works for compiling busybox with Aboriginal Linux.
7175 said:
Edit: Alright cool I found the source for Aboriginal Linux at landley.net/aboriginal and am building on Android now. I'm also trying this on my x86_64 laptop so that I can compare the differences like I have with glibc, uclibc, musl, klibc binary builds in a native environment and a cross-compile environment.
I see from my laptop's build that a busybox was generated, but it was dynamic and has a libc.so.6 dependency. @ndrancs : this might be what you were talking about. Did you try compiling static? Also see if "make allnoconfig && make clean && make LDFLAGS=-static" works for compiling busybox with Aboriginal Linux.
Click to expand...
Click to collapse
I preferred to use uclibc I think it easy to setup and produced small binary.. Aboriginal cross-compiler use uclibc as default. Btw I don't use cmd : LDFLAGS=-static instead I set it in .config.. Maybe I try this later..
ndrancs said:
I preferred to use uclibc mk it easy to setup and produced small binary.. Aboriginal cross-compiler use uclibc as default. Btw I don't use cmd : LDFLAGS=-static instead I set it in .config.. Maybe I try this later..
Click to expand...
Click to collapse
Ok yeah I like how aboriginal set up with uclibc, and it has scripts for each build stage, so you can stop at the toolchain. I'll be interested to see their future releases with the musl libc as well.
Also for anyone interested, I figured out how to run dynamic binaries in android:
- make the directories "/lib" and "/lib/arm-linux-gnueabihf"
Code:
mkdir -p /lib/arm-linux-gnueabihf
- copy the linker "ld-linux-armhf.so.3" to "/lib"
- find a specific binary's dependencies: e.g. for dynamic mksh do:
Code:
strings mksh | grep \\.so
- copy the listed libs to "/lib/arm-linux-gnueabihf": e.g. for mksh that would be libc.so.6. The libs/linker you copy over will come from the mounted ubuntu/debian/... image you have mounted like with "Complete Linux Installer".
- adjust your LD_LIBRARY_PATH:
Code:
LD_LIBRARY_PATH=/lib:/lib/arm-linux-gnueabihf:$LD_LIBRARY_PATH
Any plan to update the busybox to current version. Thanks.
@7175 can you update flashable zip to 1.23.0 stable ?
@ndrancs @exodius48 : Thanks for notifying me guys, I needed to get around to updating to 1.23.0 stable. I updated the original post with no-edify installers for busybox 1.23.0 stable. There's a non-SELinux uclibc compiled version and a full 386-applet SELinux glibc compiled version. They're included in this post too for ease.
7175 said:
@ndrancs @exodius48 : Thanks for notifying me guys, I needed to get around to updating to 1.23.0 stable. I updated the original post with no-edify installers for busybox 1.23.0 stable. There's a non-SELinux uclibc compiled version and a full 386-applet SELinux glibc compiled version. They're included in this post too for ease.
Click to expand...
Click to collapse
Great..been waiting for this release.. :good:
Btw, can i use busybox_full_selinux.zip on android 4.2.2 MIUI rom?
exodius48 said:
Great..been waiting for this release.. :good:
Btw, can i use busybox_full_selinux.zip on android 4.2.2 MIUI rom?
Click to expand...
Click to collapse
Yeah that should work just fine. I'm pretty sure any SELinux tools or applet flags should work since 4.2 introduced SELinux to its filesystem. Let me know if there are any issues.
7175 said:
Yeah that should work just fine. I'm pretty sure any SELinux tools or applet flags should work since 4.2 introduced SELinux to its filesystem. Let me know if there are any issues.
Click to expand...
Click to collapse
Great release..busybox_full_selinux.zip working fine so far on MIUI rom V5 android 4.2.2. :victory:
7175 said:
@ndrancs @exodius48 : Thanks for notifying me guys, I needed to get around to updating to 1.23.0 stable. I updated the original post with no-edify installers for busybox 1.23.0 stable. There's a non-SELinux uclibc compiled version and a full 386-applet SELinux glibc compiled version. They're included in this post too for ease.
Click to expand...
Click to collapse
Hey @7175
Great guide. I am able to compile just fine on my device using your guide. However, is there any way to compile the selinux applets support using a Linux PC (or NDK)? I am not able to find a selinux supported toolchain. May be you can help.

[Guide] Building post 2017 android kernel from source

About this guide
I have been building kernels for many machine types and have been fiddling around with custom android kernels for my own phone but to my great frustration the rules changed quite a lot for my new phone. It seems every kernel after 2017 is A LOT harder to build and needs quite some fiddling around te get it to boot. The documentation is terrible the least on the steps and all howtos are all outdated by now. This guide shares with you the secrets to build yourself a modern post 2017 kernel from source. I only own a op7 at this moment but I am pretty sure the rules apply to all devices.
So why do we need to build our own kernel? Well that's simple. I have scrolled through many custom kernels missing a simple module that I need. In my case binfmt. Perhaps you need a specific device driver compiled into your kernel or you want to hack in/patch in some special functions that are only needed by you. Or you love a certain kernel but need that one little adjustment in the configs that this kernel doesn’t have and so on.
Lets get through it step by step but I do assume you know something about Linux, you know how to use the terminal and that you have some knowledge on building binaries from source. Ready? Ok lets get started.
These steps are required to be followed to be successful:
1. Set up a building environment
2. Obtain the kernel source
3. Download the proper tool-chain
4. Adjust configuration files to match your needs
5. Build the actual kernel image
6. Backup your current boot.img!!!
7. Trow the image into a anykernel zip and flash it.
8. Close your eyes prey and run the kernel.
Prerequisites
You will need:
A fairly fast computer with lets say 4 gigs of RAM and a decent CPU.
A workable linux distribution that you can boot into (I prefer ubuntu bionic at this moment).
The kernel sources for your device.
ROOT!!
Lots of spare time.
A attitude that makes you unstoppable.
1. Setting up the building environment
Ok lets first open a terminal. You will need the terminal a lot. As a matter of fact it will be your friend through this guide so better get used to it. Assuming you are on a ubuntu like distribution lets fetch the important packages first
Code:
$sudo apt install build-essential bizon flex git
This command will install some of the prerequisites you need to do anything. More packages will need to be installed on the way but at least you will be able to type $make
Now lets create a working directory. Go into your home folder and create a working directory which will later on contain your kernel sources and tool chain.
Code:
$cd
$mkdir [COLOR="MediumTurquoise"]name-of-your-working-folder[/COLOR]
2. Obtain the kernel source
This one is tricky as my experience have learned me the kernel sources supplied by my own vendor are usually badly documented and contain a few bugs here and there resulting in either build errors or a unbootable kernel. So usually I grab a custom kernel that has minimal changes to the stock kernel and boots by only using a single kernel file without extra kernel modules attached. The custom kernels usually have the nasty building bugs flawed out and thus your chances for success are higher. I used the exkernel in my case and out of respect for the hard work of flang2 I bought the app that came along.
To get the sources google around and find the sources on for example git and click the download or clone button there and copy the link of the depository.
Then simply clone the depository to your working directory so after changing to your working directory type
Code:
$git clone link-you-just-copied
Git will now automatically clone the entire kernel source into the source sub-directory. You can change the name of this directory to make you life easier.
3. Download the proper tool-chain
This is where I lost many days and weeks of my life. Where do we find the proper tool-chain for our kernel?
You basically need 3 compilers
clang
GCC
device-tree-compiler
There are many versions of clang and GCC and you will need to find the one that matches your kernel and builds for your cpu architecture. I will assume in this guide that your CPU is aarch64 or arm64 (both names are used at the same time).
To obtain clang head over to the following address:
"https://android.googlesource.com/platform/prebuilts/clang/host/linux-x86/"
now in the tags and branches you can find the version of android you are looking for. If your kernel is for android 9 then use the android 9 tag. Click on it and then click tgz which will provide you with a huge tarball.
Create a folder in your working directory named toolchain en extract the contents of the tarball into the sub-folder clang.
You can try any subversion of clang there is but I recommend to simply peek into the build.config files located in the root of your kernel source directory which usually specify the exact subversion of clang used.
Time to get GCC which is easier since there is only one version right now.
Head over to
"https://android.googlesource.com/platform/prebuilts/gcc/linux-x86/arm/arm-linux-androideabi-4.9/"
and use the correct version here as well. In my case I picked the latest build. Then do the same as for clang but name the sub-folder GCC or whatever you please to do.
And then finally get yourself the device-tree-compiler
Head over to
"https://github.com/dgibson/dtc/tree/v1.4.4"
and clone this depository into ~/your-working-directory/toolchain/
and navigate to the subdir you cloned it into
then build by typing
Code:
$make
any missing package errors will need you to install them using
Code:
$sudo apt install missing-package-name
and do make again until the build completes.
If all went well your tool-chain and working directory will look like this:
Code:
/[COLOR="mediumturquoise"]current-working-dir[/COLOR]/[COLOR="mediumturquoise"]kernel-source-dir[/COLOR]/
|
/toolchain/
|
/clang/
/gcc/
/dtc/
4. Adjust configuration files to match your needs
Lets first grab the correct defconfig file and setup the build directory. This defconfig file contains the default kernel configuration parameters which you propably want to adjust.
Head over to ~/working-directory/kernel-source-dir/arch/arm64/configs/
see what you can find there. I found the elementalX_defconfig file which is the file I needed to build the Exkernel from scratch. If you are trying a stock kernel dive a little bit deeper into the vendor folder and see if you can find a good config file there.
Alternatively sometimes the config is hidden on your device itself. Have a look at
/proc/config.gz
the file inside the archive contains a valid defconfig for your device but beware your may need to open it with menuconfig first and save it again to make it workable for the compiler script.
Place the defconfig file you like to use into the configs folder.
(Skip the following step if your are going to build your kernel for the first time because we first want to see it work.)
Now head over to your kernel source dir and type the following command
Code:
$PATH="~/[COLOR="mediumturquoise"]working-dir[/COLOR]/toolchain/clang/[COLOR="mediumturquoise"]clang-r353983c[/COLOR]/bin:~/[COLOR="mediumturquoise"]working-dir[/COLOR]/toolchain/gcc/a[COLOR="mediumturquoise"]arch64-linux-android-4.9[/COLOR]/bin:${PATH}" \
make menuconfig O=out \
ARCH=arm64 \
CC=clang \
CLANG_TRIPLE=aarch64-linux-gnu- \
CROSS_COMPILE=aarch64-linux-android-
now remember to use the correct paths to your tool-chain. In this command I use clang-r353983c but you may use a different version. The same applies for linux-android-4.9.
I would like to thank Nathan Chance for supplying documentation on the clang tool-chain on his github.
If all well you will be presented with a menu in which you can adjust things. First open the defconfig file you wish to use and then save the file after you are done. Now REMEMBER! With this command the menuconfig will save your new file into the /kernel-source-dir/out folder.
(end of the skipped step)
Now it is time to prepare our kernel build using the following command (do this from your kernel source dir) and remember that this command will look in the /kernel-source-dir/arch/arm64/configs/ directory
$make O=out ARCH=arm64 name-of-your-defconfig
If all goes well you will see something like configuration written to .config
Everything is up and ready to go. Your hart will start pounding from this moment on
5. Build the actual kernel image
This is where things get complicated. I hope you have many years to live because this part consumes time, a lot of it.
type
Code:
$PATH="~/[COLOR="mediumturquoise"]working-dir[/COLOR]/toolchain/clang/[COLOR="mediumturquoise"]clang-r353983c[/COLOR]/bin:~/[COLOR="mediumturquoise"]working-dir[/COLOR]/toolchain/gcc/[COLOR="mediumturquoise"]aarch64-linux-android-4.9[/COLOR]/bin:${PATH}" \
make -j$(nproc --all) O=out \
ARCH=arm64 \
CC=clang \
DTC=~/[COLOR="mediumturquoise"]working-directory[/COLOR]/toolchain/dtc/dtc \
CLANG_TRIPLE=aarch64-linux-gnu- \
CROSS_COMPILE=aarch64-linux-android-
ready set GO!
This will depending on your machine take between forever and eternally. You will witness many warnings on the DTC build seems normal these days and a few warnings on the CC part. Most important is that no errors are thrown at you.
If all goes well you will see a normal exit status and you will have a “working” kernel image.
“Error?: Well that happens. Try a different build of clang check your command line. And if all that fails try to find out what is wrong in the source and that means digging through thousands of forum pages until you find out whats wrong. But using the google tools usually goes well.”
Almost there go and check
kernel-source-dir/out/arch/arm64/boot
and there should be a image-dtb or image.gz-dtb file depending on you settings.
That is your kernel image right there. The difference in size between image and image-dtb should not be huge. 10Megs in difference usually means your dtb is not good but trying is the only way to find out if it works.
6. Backup your current boot.img!!!
You know what to do here right? Do not skip this step unless you like bricked devices or want to reflash and lose your data and all that kind of stuff. Not sure what you are doing stop here or backup your entire device including system vendor etc.
7. Trow the image into a anykernel zip and flash it.
Ok something changed in the last few years. Unpacking repacking and booting using fastboot somehow gives me problems. Dm-verity errors and all kind of red screens. Signing the boot image results into new errors. Well this is how I did it.
Get yourself a anykernel zip file. I used the Exkernel.zip because it only contains a kernel image which I like. Open the zip in a good zip tool (I used ark) and replace the image-dtb file with the one you created. Place this new zip you created on a memory stick and then….
Flash it using twrp or any tool of choice.
8. Close your eyes prey and run the kernel.
Two things can happen.
1. Blank screen nothing happens. Only god can help you, repeat all the steps.
2. Your android starts booting. Start crying of joy
Check in your android if this is indeed the kernel you build. If so time to make some adjustments to your configs or happily enjoy your boosted phone.
Now please remember. If you plan to distribute your kernel that you do the correct steps of accrediting the original programmer and trow the source online. If you use a already custom kernel please respect the hard work of the maker and communicate your plans with him/her.

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