Pixel3XL 构建自己的内核

1. 找到Pixel 3XL对应的内核版本
   https://source.android.com/docs/setup/build/building-kernels?hl=zh-cn#supported-kernel-branches
   Pixel 3 XL (crosshatch) android-msm-crosshatch-4.9-android12
2. 下载内核源代码

mkdir android-kernel && cd android-kernel
repo init -u https://android.googlesource.com/kernel/manifest -b android-msm-crosshatch-4.9-android12
repo sync -cdj4

3. 删除源码下载的img

cd out/target/product/crosshatch

$rm *.img kernel
rm: remove regular file 'boot-debug.img'? 
rm: remove regular file 'boot.img'? 
rm: remove regular file 'bootloader.img'? 
rm: remove regular file 'boot-test-harness.img'? 
rm: remove regular file 'dtb.img'? 
rm: remove regular file 'dtbo.img'? 
rm: remove regular file 'persist.img'? 
rm: remove regular file 'product.img'? 
rm: remove regular file 'radio.img'? 
rm: remove regular file 'ramdisk-debug.img'? 
rm: remove regular file 'ramdisk.img'? 
rm: remove regular file 'ramdisk-recovery.img'? 
rm: remove regular file 'ramdisk-test-harness.img'? 
rm: remove regular file 'super_empty.img'? 
rm: remove regular file 'system_ext.img'? 
rm: remove regular file 'system.img'? 
rm: remove regular file 'system_other.img'? 
rm: remove regular file 'userdata.img'? 
rm: remove regular file 'vbmeta.img'? 
rm: remove regular file 'vendor.img'? 
rm: remove regular file 'kernel'? 

TODO: 这里是不是删除boot.img和kernel就可以了？

4. 替换Image.lz4

mv Image.lz4 ../../../../android_backup

等待kernel编译完成，编译完成之后：

cp /home/fukaiqiang/work/android-kernel/out/android-msm-pixel-4.9/dist/Image.lz4 /home/fukaiqiang/work/code/device/google/crosshatch-kernel

5. 再次编译android工程

source build/envsetup.sh
lunch aosp_crosshatch-userdebug
make -j16

6. 刷机
   还不知道如何编译下载和编译和刷写android源码的，可以看这篇文章 https://www.jianshu.com/p/8c402a0210d9

参考：https://juejin.cn/post/7250756790240018492#heading-28