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+Le Max2 Kernel Build mini-Howto
+===============================
+
+1. Build
+--------
+
+- get toolchain
+    From android git server, codesourcery etc.
+    - `aarch64-linux-android-4.9`
+
+- Unpack kernel source
+    Suppose kernel source has been unpacked to `<kernel>` dir.
+
+- export env variables
+    export correct `CROSS_COMPILE` to use the toolchain path you have downloaded.
+
+```
+$ export CROSS_COMPILE="<android_platform_dir>/prebuilts/gcc/linux-x86/aarch64/aarch64-linux-android-4.9/bin/aarch64-linux-android-"
+```
+
+```
+$ export JOBS=16    # Can be CPU core # x 2
+```
+
+- build kernel
+
+```
+$ cd <kernel>
+```
+
+```
+$ make -C $PWD O=$PWD/out ARCH=arm64 msm-perf_defconfig
+```
+
+```
+$ make -j$JOBS -C $PWD O=$PWD/out ARCH=arm64 KCFLAGS=-mno-android
+```
+
+```
+$ make -j$JOBS -C $PWD O=$PWD/out ARCH=arm64 KCFLAGS=-mno-android modules
+```
+
+2. Output files
+---------------
+
+- Kernel: `out/arch/arm64/boot/Image`
+- Kernel modules: `out/drivers/*/*.ko`
+
+3. Clean up
+-----------
+
+```
+$ rm -rf out
+```