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+# How to build KernelSU?
+
+First, you should read the Android Official docs for kernel build:
+
+1. [Building Kernels](https://source.android.com/docs/setup/build/building-kernels)
+2. [GKI Release Builds](https://source.android.com/docs/core/architecture/kernel/gki-release-builds)
+
+## Build Kernel
+
+### Sync the kernel source code
+
+```sh
+repo init -u https://android.googlesource.com/kernel/manifest
+mv <kernel_manifest.xml> .repo/manifests
+repo init -m manifest.xml
+repo sync
+```
+
+The `<kernel_manifest.xml>` is a manifest file which can determine a build uniquely, you can use the manifest to do a re-preducable build. You should download the manifest file from [Google GKI release builds](https://source.android.com/docs/core/architecture/kernel/gki-release-builds)
+
+### Build
+
+Please check the [official docs](https://source.android.com/docs/setup/build/building-kernels) first.
+
+For example, we need to build aarch64 kernel image:
+
+```sh
+LTO=thin BUILD_CONFIG=common/build.config.gki.aarch64 build/build.sh
+```
+
+Don't forget to add the `LTO=thin` flag, otherwise the build may fail if your computer's memory is less then 24Gb.
+
+Starting from Android 13, the kernel is built by `bazel`:
+
+```sh
+tools/bazel build --config=fast //common:kernel_aarch64_dist
+```
+
+## Build Kernel with KernelSU
+
+If you can build the kernel successfully, then build KernelSU is so easy, run this command in Kernel source root dir:
+
+```sh
+curl -LSs "https://raw.githubusercontent.com/tiann/KernelSU/main/kernel/setup.sh" | bash -
+```
+
+And then rebuild the kernel and you will get a kernel image with KernelSU!