[REFERENCE] How to compile an Android kernel

[nathanchance]

Hi..Sir Flash,

I want to ask a question for ARM Device. ( Nexus 6 )

This is right method for ARM?

example:

- - - - -
export CROSS_COMPILE=${HOME}/Kernel/Toolchain/bin/arm-eabi-

export ARCH=arm && export SUBARCH=arm

make clean && make mrproper

make shamu_defconfig

make -j$(nproc --all)
- - - - -

I want to know this about.
If this method is wronged, Please teach me Sir.

Thanks.

•••

That's correct.

 

[chevycam94]

You should just be able to copy the whole file (cp .config arch/arm64/configs/marlin_defconfig).

You could run a git bisect on your kernel source and see if there is a commit causing those mismatch errors. Very rarely is that a result of a toolchain or environment configuration.

I got the mismatch errors fixed. It turned out to be this guy:

https://github.com/chevycam94/marlin_kernel/commit/b82627ead81eaca16c547e5517eea24c88ea6f61

Now all I have to do is diagnose my random system crash/ramdumps. Locking up quite a bit. This should be interesting. Not sure how to debug kernel issues. Remember, this is my first time working on a kernel.

Done plenty of ROMs, just never the kernel itself.

 

[D1stRU3T0R]

How can i test my own kernel, how can I make a flashable zip, or how should i make it in boot?

 

[nathanchance]

How can i test my own kernel, how can I make a flashable zip, or how should i make it in boot?

I cover that in step 4 lol; if you are having issues understanding any of it, you need to ask more specific questions so I can clear those up.

 

[ZawZaw]

That's correct.

Thanks The Flash.

•••

Sent from my Google Nexus 5X using XDA Labs

 

[D1stRU3T0R]

Delete

 

[kanjanja]

Introduction

Hello everyone, I will be going over how to compile a kernel from beginning to end!

Prerequisites:
A Linux environment (preferably 64-bit)
Knowledge of how to navigate the command line
Common sense
A learning spirit, there will be no spoonfeeding here


What this guide will cover:
Downloading the source
Building the kernel
Setting up a build environment (plenty of existing Linux installation guides)
Pull your device's boot image from the latest image available for your device (whether it be a ROM or stock)
Run the following with the boot image:

Run the following to repack:

Download the latest AnyKernel2 zip: https://github.com/osm0sis/AnyKernel2/archive/master.zip
Place your kernel image in the root of the file.
kernel.string: your kernel name
block: Your boot image's path in your fstab. The fstab can be opened from the root of your device and it will look something like this:
https://android.googlesource.com/device/huawei/angler/+/master/fstab.angler
The first column is the value you want to set block to.

[*]After that, zip up the kernel and flash it!

[/LIST][/HIDE][/HIDE]


Tips and tricks

1. Remove GCC wrapper

A lot of kernels from CAF include a Python script that will essentially turn on -Werror, causing your build to error at the most benign stuff. This is necessary with higher GCC versions as there are a lot more warnings.

Here is the diff of what you need to change in the Makefile:

2. Using a higher level GCC toolchain

Using a higher GCC toolchain (5.x, 6.x, 7.x or even 8.x) will require you to nuke the GCC wrapper script as above and use a unified GCC header file (pick the following if you have an include/linux/compiler-gcc#.h file):

3.4/3.10: https://git.kernel.org/pub/scm/linu...h?id=a4a4f1cd733fe5b345db4e8cc19bb8868d562a8a
3.18: https://git.kernel.org/pub/scm/linu...h?id=677fa15cd6d5b0843e7b9c58409f67d656b1ec2f

You may get a lot of warnings but they are not entirely necessary to fix.

3. Adding upstream Linux to kernel source

Once you have gotten familiar with git and the compilation process, you should consider upstreaming your kernel. This will allow you to stay on top of CVE and bug fixes by staying up to date with the latest work of the Linux kernel developers.

Receiving help

I am happy to answer anything that I touched on in this guide. I may point you to another thread if it's better suited but I don't mind off topic (within reason) within the thread. I also want this to be a collaborative effort; other developers, if you have something to add, correct, or improve upon, please let me know!

I am particular in how people ask for help. I do NOT respond to posts asking for a hand out ("How do I fix this?", "Please fix this!", etc.). I only respond to posts with clear logs and steps that you have tried. Basically, show me that you have read this guide and have a specific issue. I am not here to hold your hand through this, this is a developers' forum.

This is interesting

 

[kosmitchak]

Hi i'm trying to compile Kernel for P8 lite (emui 4.1 ALE-L21) but i'm getting errors and compiling stops.

https://pastebin.com/pRT4AgMA

I don't know what is wrong can somebody help me?

Source code: https://github.com/kosmitchak/android_kernel_huawei_hi6210sft/tree/android6?files=1

Thanks!

 

[DSA]

Hi i'm trying to compile Kernel for P8 lite (emui 4.1 ALE-L21) but i'm getting errors and compiling stops.

https://pastebin.com/pRT4AgMA

I don't know what is wrong can somebody help me?

Source code: https://github.com/kosmitchak/android_kernel_huawei_hi6210sft/tree/android6?files=1

Thanks!

i would guess this is the part:

aarch64-linux-android-ld: no input files
scripts/Makefile.build:454: polecenia dla obiektu 'init/mounts.o' nie powiodły się
make[1]: *** [init/mounts.o] Błąd 1
  CC      arch/arm64/mm/copypage.o
Makefile:883: polecenia dla obiektu 'init' nie powiodły się
make: *** [init] Błąd 2
make: *** Oczekiwanie na niezakończone zadania....

 

[kosmitchak]

i would guess this is the part:

Yes i know but i don't know what is wrong with it.

 

[D1stRU3T0R]

Hi i'm trying to compile Kernel for P8 lite (emui 4.1 ALE-L21) but i'm getting errors and compiling stops.

https://pastebin.com/pRT4AgMA

I don't know what is wrong can somebody help me?

Source code: https://github.com/kosmitchak/android_kernel_huawei_hi6210sft/tree/android6?files=1

Thanks!

Hi, no reason why to compile emui 4.1bif you're not Vodafone user..

 

[kosmitchak]

Hi, no reason why to compile emui 4.1bif you're not Vodafone user..

Emui 4.0 Kernel source is outdated

 

[D1stRU3T0R]

Emui 4.0 Kernel source is outdated

I know, but emui 4.1 Kernel won't boot on emui 4.0.3 :/ i think latest and best is Esal...but at first upstream i got 4 commits to resolve.

 

[kosmitchak]

Now i started working on emui 4.0 Kernel source, maybe we can cooperate xD

 

[Mandy $ingh]

https://pastebin.com/dDc3aiqs got error while compiling plz help and source link is https://github.com/jcadduono/android_kernel_samsung_exynos7870

 

[Gingernut78]

Thank you for the detailed tutorial on kernel building.

I've followed this guide and successfully built the lineageos Mi5s kernel without errors using Google's 4.9 prebuilt cross compiler.

The only modifications to the source code I made were to resolve building errors, nothing else, but unfortunately it doesn't boot.

I kindly asked the developers for some enlightening as to why but was told that they don't build the standalone kernel so can't help.

Would it have anything to do with no dt.img and not using dtbTool?

My zImage.gz-dtb image was repacked with the latest lineageos boot.img and also tried with Anykernel2.

Any help is kindly appreciated and sorry if this is way off topic :angel: .

 

[Jleeblanch]

Thanks for this, glad to see someone made an updated kernel compilation guide. A while back, I had done some extensive searching trying to learn how to build and compile a kernel. As there was no updated info, it was quite a learning experience to say the least! I had to use bits a pieces of guides here on xda, info from GitHub, info from within the kernel source documentation and various other Google searches to finally be able to successfully build a kernel.

Point is, thank you for an updated reference guide, you the man [emoji6]

 

[D1stRU3T0R]

Delete lol

 

[D1stRU3T0R]

What I should do?

 

[zhaozihanzzh]

What I should do?

It seems that there are errors, so you can check the information and find errors which cause sub-make failed. Sorry, I am a noob.

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