en/setup/build/building-kernels.html - platform/docs/source.android.com - Git at Google

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 <p>
   This page details how to build only the
   <a href="/devices/architecture/kernel/">kernel</a>. The following instructions
   assume you have not downloaded all of AOSP; if you have already done so, you
   can skip the <code>git clone</code> steps except the step that downloads the
   kernel sources.
 </p>

 <p>All examples in this section use the
 <a href="devices.html#hikey-boards">hikey</a> kernel.</p>

 <h2 id="figuring-out-which-kernel-to-build">Selecting a kernel</h2>
 <p>This table lists the name and locations of the kernel sources and binaries:
 <table>
   <tr>
     <th>Device</th>
     <th>Binary location</th>
     <th>Source location</th>
     <th>Build configuration</th>
   </tr>
   <tr>
     <td>blueline</td>
     <td>device/google/crosshatch-kernel</td>
     <td><a href="#building-b1c1">instructions</a></td>
     <td>b1c1_defconfig</td>
   </tr>
   <tr>
     <td>crosshatch</td>
     <td>device/google/crosshatch-kernel</td>
     <td><a href="#building-b1c1">instructions</a></td>
     <td>b1c1_defconfig</td>
   </tr>
   <tr>
     <td>taimen</td>
     <td>device/google/wahoo-kernel</td>
     <td>kernel/msm</td>
     <td>wahoo_defconfig</td>
   </tr>
   <tr>
     <td>walleye</td>
     <td>device/google/wahoo-kernel</td>
     <td>kernel/msm</td>
     <td>wahoo_defconfig</td>
   </tr>
   <tr>
     <td>easel</td>
     <td>N/A</td>
     <td>kernel/arm64</td>
     <td>mnh_prod_defconfig</td>
   </tr>
   <tr>
     <td>marlin</td>
     <td>device/google/marlin-kernel</td>
     <td>kernel/msm</td>
     <td>marlin_defconfig</td>
   </tr>
   <tr>
     <td>sailfish</td>
     <td>device/google/marlin-kernel</td>
     <td>kernel/msm</td>
     <td>marlin_defconfig</td>
   </tr>
   <tr>
     <td>hikey</td>
     <td>device/linaro/hikey-kernel</td>
     <td>kernel/hikey-linaro</td>
     <td>hikey_defconfig</td>
   </tr>
   <tr>
     <td>angler</td>
     <td>device/huawei/angler-kernel</td>
     <td>kernel/msm</td>
     <td>angler_defconfig</td>
   </tr>
   <tr>
     <td>bullhead</td>
     <td>device/lge/bullhead-kernel</td>
     <td>kernel/msm</td>
     <td>bullhead_defconfig</td>
   </tr>
   <tr>
     <td>shamu</td>
     <td>device/moto/shamu-kernel</td>
     <td>kernel/msm</td>
     <td>shamu_defconfig</td>
   </tr>
   <tr>
     <td>fugu</td>
     <td>device/asus/fugu-kernel</td>
     <td>kernel/x86_64</td>
     <td>fugu_defconfig</td>
   </tr>
   <tr>
     <td>volantis</td>
     <td>device/htc/flounder-kernel</td>
     <td>kernel/tegra</td>
     <td>flounder_defconfig</td>
   </tr>
   <tr>
     <td>hammerhead</td>
     <td>device/lge/hammerhead-kernel</td>
     <td>kernel/msm</td>
     <td>hammerhead_defconfig</td>
   </tr>
   <tr>
     <td>flo</td>
     <td>device/asus/flo-kernel/kernel</td>
     <td>kernel/msm</td>
     <td>flo_defconfig</td>
   </tr>
   <tr>
     <td>deb</td>
     <td>device/asus/flo-kernel/kernel</td>
     <td>kernel/msm</td>
     <td>flo_defconfig</td>
   </tr>
   <tr>
     <td>manta</td>
     <td>device/samsung/manta/kernel</td>
     <td>kernel/exynos</td>
     <td>manta_defconfig</td>
   </tr>
   <tr>
     <td>mako</td>
     <td>device/lge/mako-kernel/kernel</td>
     <td>kernel/msm</td>
     <td>mako_defconfig</td>
   </tr>
   <tr>
     <td>grouper</td>
     <td>device/asus/grouper/kernel</td>
     <td>kernel/tegra</td>
     <td>tegra3_android_defconfig</td>
   </tr>
   <tr>
     <td>tilapia</td>
     <td>device/asus/grouper/kernel</td>
     <td>kernel/tegra</td>
     <td>tegra3_android_defconfig</td>
   </tr>
   <tr>
     <td>maguro</td>
     <td>device/samsung/tuna/kernel</td>
     <td>kernel/omap</td>
     <td>tuna_defconfig</td>
   </tr>
   <tr>
     <td>toro</td>
     <td>device/samsung/tuna/kernel</td>
     <td>kernel/omap</td>
     <td>tuna_defconfig</td>
   </tr>
   <tr>
     <td>panda</td>
     <td>device/ti/panda/kernel</td>
     <td>kernel/omap</td>
     <td>panda_defconfig</td>
   </tr>
   <tr>
     <td>stingray</td>
     <td>device/moto/wingray/kernel</td>
     <td>kernel/tegra</td>
     <td>stingray_defconfig</td>
   </tr>
   <tr>
     <td>wingray</td>
     <td>device/moto/wingray/kernel </td>
     <td>kernel/tegra</td>
     <td>stingray_defconfig</td>
   </tr>
   <tr>
     <td>crespo</td>
     <td>device/samsung/crespo/kernel</td>
     <td>kernel/samsung</td>
     <td>herring_defconfig</td>
   </tr>
   <tr>
     <td>crespo4g</td>
     <td>device/samsung/crespo/kernel</td>
     <td>kernel/samsung</td>
     <td>herring_defconfig</td>
   </tr>
 </table>

 <p>After determining the device project you want to work with, view the git log
 for the kernel binary. Device projects use the form
 <code>device/<var>VENDOR</var>/<var>NAME</var></code>.</p>

 <pre class="devsite-click-to-copy">
 <code class="devsite-terminal">git clone https://android.googlesource.com/kernel/hikey-linaro</code>
 <code class="devsite-terminal">cd hikey-linaro</code>
 <code class="devsite-terminal">git log --max-count=1 kernel</code>
 </pre>

 <p>The commit message for the kernel binary contains a partial git log of the
 kernel sources used to build the binary. The first entry in the log is the most
 recent (the one used to build the kernel). Make a note of the commit message
 as you will need it in a later step.</p>

 <h2 id="id-version">Identifying kernel version</h2>

 <p>To determine the kernel version used in a system image, run the following
 command against the kernel file:</p>

 <pre class="devsite-terminal devsite-click-to-copy">
 dd if=kernel bs=1 skip=$(LC_ALL=C grep -a -b -o $'\x1f\x8b\x08\x00\x00\x00\x00\x00' kernel | cut -d ':' -f 1) | zgrep -a 'Linux version'
 </pre>

 <p>For Nexus 5 (hammerhead), the command is:</p>
 <pre class="devsite-terminal devsite-click-to-copy">
 dd if=zImage-dtb bs=1 skip=$(LC_ALL=C od -Ad -x -w2 zImage-dtb | grep 8b1f | cut -d ' ' -f1 | head -1) | zgrep -a 'Linux version'
 </pre>


 <h2 id="downloading-sources">Downloading sources</h2>
 <p>Download the source for the kernel you want to build using the appropriate
 <code>git clone</code> command. For example, the following command clones the
 <code>common</code> kernel, a generic, customizable kernel:</p>
 <pre class="devsite-terminal devsite-click-to-copy">
 git clone https://android.googlesource.com/kernel/common
 </pre>

 <p>A full list of the kernel projects can be found in the
 <a href="https://android.googlesource.com/kernel">Kernel</a> directory. Below
 are some of the commonly used kernels and their respective <code>git clone</code>
 commands.</p>

 <p>The <code>exynos</code> project has the kernel sources for Nexus 10, and can
 be used as a starting point for work on Samsung Exynos chipsets.</p>
 <pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/exynos</pre>

 <p>The <code>goldfish</code> project contains the kernel sources for the
 emulated platforms.</p>
 <pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/goldfish</pre>

 <p>The <code>hikey-linaro</code> project is used for HiKey reference boards,
 and can be used as a starting point for work on HiSilicon 620 chipsets.</p>
 <pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/hikey-linaro</pre>

 <p>The <code>msm</code> project has the sources for ADP1, ADP2, Nexus One,
 Nexus 4, Nexus 5, Nexus 6, Nexus 5X, Nexus 6P, Nexus 7 (2013), Pixel, and
 Pixel XL, and can be used as a starting point for work on Qualcomm MSM chipsets.</p>
 <pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/msm</pre>

 <p>The <code>omap</code> project is used for PandaBoard and Galaxy Nexus, and
 can be used as a starting point for work on TI OMAP chipsets.</p>
 <pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/omap</pre>

 <p>The <code>samsung</code> project is used for Nexus S, and can be used as a
 starting point for work on Samsung Hummingbird chipsets.</p>
 <pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/samsung</pre>

 <p>The <code>tegra</code> project is for Xoom, Nexus 7 (2012), Nexus 9, and can
 be used as a starting point for work on NVIDIA Tegra chipsets.</p>
 <pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/tegra</pre>

 <p>The <code>x86_64</code> project has the kernel sources for Nexus Player, and
 can be used as a starting point for work on Intel x86_64 chipsets.</p>
 <pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/x86_64</pre>

 <h2 id="building">Building the kernel manually</h2>
 <p>When you know the last commit message for a kernel and have successfully
 downloaded the kernel source and prebuilt gcc, you are ready to build the
 kernel. The following build commands use the hikey kernel:</p>
 <pre class="devsite-click-to-copy">
 <code class="devsite-terminal">export ARCH=arm64</code>
 <code class="devsite-terminal">export CROSS_COMPILE=aarch64-linux-android-</code>
 <code class="devsite-terminal">cd hikey-linaro</code>
 <code class="devsite-terminal">git checkout -b android-hikey-linaro-4.1 origin/android-hikey-linaro-4.1</code>
 <code class="devsite-terminal">make hikey_defconfig</code>
 <code class="devsite-terminal">make</code>
 </pre>

 <p>To build a different kernel, simply replace <code>hikey-linaro</code> with
 the name of the kernel you want to build.</p>

 <p>The image outputs to the <code>arch/arm64/boot/Image</code> directory; the
 kernel binary outputs to the
 <code>arch/arm64/boot/dts/hisilicon/hi6220-hikey.dtb</code> fle. Copy the
 <code>Image</code> directory and the <code>hi6220-hikey.dtb</code> file to the
 <code>hikey-kernel</code> directory.</p>

 <p>Alternatively, you can include the <code>TARGET_PREBUILT_KERNEL</code>
 variable while using <code>make bootimage</code> (or any other <code>make</code>
 command line that builds a boot image). This variable is supported by all
 devices as it is set up via <code>device/common/populate-new-device.sh</code>.
 For example:</p>

 <pre class="devsite-terminal devsite-click-to-copy">
 export TARGET_PREBUILT_KERNEL=$your_kernel_path/arch/arm/boot/zImage-dtb
 </pre>

 <p class="note"><strong>Note:</strong> Kernel names differ by device. To locate
 the correct filename for your kernel, refer to
 <code>device/<var>VENDOR</var>/<var>NAME</var></code> in the kernel source.</p>


 <h2 id="building-b1c1">Building Pixel 3 (blueline) and Pixel 3 XL (crosshatch) kernels</h2>

 <p>For Pixel 3 and Pixel 3 XL, the kernel source is separated into multiple
 projects. Use <a href="/setup/develop/repo#init">repo</a> to download the
 kernel source for the appropriate branch (as of this writing, <code><var>VERSION</var></code> should be
 <code>4.9-pie-qpr1</code>):</p>

 <pre class="devsite-terminal devsite-click-to-copy">repo init -u https://android.googlesource.com/platform/manifest -b android-msm-bluecross-$<var>VERSION</var></pre>
 <pre class="devsite-terminal devsite-click-to-copy">repo sync</pre>

 <p>Then build the kernel with:</p>

 <pre class="devsite-terminal devsite-click-to-copy">sh build/build.sh</pre>
   </body>
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	Copyright 2017 The Android Open Source Project

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	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	See the License for the specific language governing permissions and
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	<p>
	This page details how to build only the
	<a href="/devices/architecture/kernel/">kernel</a>. The following instructions
	assume you have not downloaded all of AOSP; if you have already done so, you
	can skip the <code>git clone</code> steps except the step that downloads the
	kernel sources.
	</p>

	<p>All examples in this section use the
	<a href="devices.html#hikey-boards">hikey</a> kernel.</p>

	<h2 id="figuring-out-which-kernel-to-build">Selecting a kernel</h2>
	<p>This table lists the name and locations of the kernel sources and binaries:
	<table>
	<tr>
	<th>Device</th>
	<th>Binary location</th>
	<th>Source location</th>
	<th>Build configuration</th>
	</tr>
	<tr>
	<td>blueline</td>
	<td>device/google/crosshatch-kernel</td>
	<td><a href="#building-b1c1">instructions</a></td>
	<td>b1c1_defconfig</td>
	</tr>
	<tr>
	<td>crosshatch</td>
	<td>device/google/crosshatch-kernel</td>
	<td><a href="#building-b1c1">instructions</a></td>
	<td>b1c1_defconfig</td>
	</tr>
	<tr>
	<td>taimen</td>
	<td>device/google/wahoo-kernel</td>
	<td>kernel/msm</td>
	<td>wahoo_defconfig</td>
	</tr>
	<tr>
	<td>walleye</td>
	<td>device/google/wahoo-kernel</td>
	<td>kernel/msm</td>
	<td>wahoo_defconfig</td>
	</tr>
	<tr>
	<td>easel</td>
	<td>N/A</td>
	<td>kernel/arm64</td>
	<td>mnh_prod_defconfig</td>
	</tr>
	<tr>
	<td>marlin</td>
	<td>device/google/marlin-kernel</td>
	<td>kernel/msm</td>
	<td>marlin_defconfig</td>
	</tr>
	<tr>
	<td>sailfish</td>
	<td>device/google/marlin-kernel</td>
	<td>kernel/msm</td>
	<td>marlin_defconfig</td>
	</tr>
	<tr>
	<td>hikey</td>
	<td>device/linaro/hikey-kernel</td>
	<td>kernel/hikey-linaro</td>
	<td>hikey_defconfig</td>
	</tr>
	<tr>
	<td>angler</td>
	<td>device/huawei/angler-kernel</td>
	<td>kernel/msm</td>
	<td>angler_defconfig</td>
	</tr>
	<tr>
	<td>bullhead</td>
	<td>device/lge/bullhead-kernel</td>
	<td>kernel/msm</td>
	<td>bullhead_defconfig</td>
	</tr>
	<tr>
	<td>shamu</td>
	<td>device/moto/shamu-kernel</td>
	<td>kernel/msm</td>
	<td>shamu_defconfig</td>
	</tr>
	<tr>
	<td>fugu</td>
	<td>device/asus/fugu-kernel</td>
	<td>kernel/x86_64</td>
	<td>fugu_defconfig</td>
	</tr>
	<tr>
	<td>volantis</td>
	<td>device/htc/flounder-kernel</td>
	<td>kernel/tegra</td>
	<td>flounder_defconfig</td>
	</tr>
	<tr>
	<td>hammerhead</td>
	<td>device/lge/hammerhead-kernel</td>
	<td>kernel/msm</td>
	<td>hammerhead_defconfig</td>
	</tr>
	<tr>
	<td>flo</td>
	<td>device/asus/flo-kernel/kernel</td>
	<td>kernel/msm</td>
	<td>flo_defconfig</td>
	</tr>
	<tr>
	<td>deb</td>
	<td>device/asus/flo-kernel/kernel</td>
	<td>kernel/msm</td>
	<td>flo_defconfig</td>
	</tr>
	<tr>
	<td>manta</td>
	<td>device/samsung/manta/kernel</td>
	<td>kernel/exynos</td>
	<td>manta_defconfig</td>
	</tr>
	<tr>
	<td>mako</td>
	<td>device/lge/mako-kernel/kernel</td>
	<td>kernel/msm</td>
	<td>mako_defconfig</td>
	</tr>
	<tr>
	<td>grouper</td>
	<td>device/asus/grouper/kernel</td>
	<td>kernel/tegra</td>
	<td>tegra3_android_defconfig</td>
	</tr>
	<tr>
	<td>tilapia</td>
	<td>device/asus/grouper/kernel</td>
	<td>kernel/tegra</td>
	<td>tegra3_android_defconfig</td>
	</tr>
	<tr>
	<td>maguro</td>
	<td>device/samsung/tuna/kernel</td>
	<td>kernel/omap</td>
	<td>tuna_defconfig</td>
	</tr>
	<tr>
	<td>toro</td>
	<td>device/samsung/tuna/kernel</td>
	<td>kernel/omap</td>
	<td>tuna_defconfig</td>
	</tr>
	<tr>
	<td>panda</td>
	<td>device/ti/panda/kernel</td>
	<td>kernel/omap</td>
	<td>panda_defconfig</td>
	</tr>
	<tr>
	<td>stingray</td>
	<td>device/moto/wingray/kernel</td>
	<td>kernel/tegra</td>
	<td>stingray_defconfig</td>
	</tr>
	<tr>
	<td>wingray</td>
	<td>device/moto/wingray/kernel </td>
	<td>kernel/tegra</td>
	<td>stingray_defconfig</td>
	</tr>
	<tr>
	<td>crespo</td>
	<td>device/samsung/crespo/kernel</td>
	<td>kernel/samsung</td>
	<td>herring_defconfig</td>
	</tr>
	<tr>
	<td>crespo4g</td>
	<td>device/samsung/crespo/kernel</td>
	<td>kernel/samsung</td>
	<td>herring_defconfig</td>
	</tr>
	</table>

	<p>After determining the device project you want to work with, view the git log
	for the kernel binary. Device projects use the form
	<code>device/<var>VENDOR</var>/<var>NAME</var></code>.</p>

	<pre class="devsite-click-to-copy">
	<code class="devsite-terminal">git clone https://android.googlesource.com/kernel/hikey-linaro</code>
	<code class="devsite-terminal">cd hikey-linaro</code>
	<code class="devsite-terminal">git log --max-count=1 kernel</code>
	</pre>

	<p>The commit message for the kernel binary contains a partial git log of the
	kernel sources used to build the binary. The first entry in the log is the most
	recent (the one used to build the kernel). Make a note of the commit message
	as you will need it in a later step.</p>

	<h2 id="id-version">Identifying kernel version</h2>

	<p>To determine the kernel version used in a system image, run the following
	command against the kernel file:</p>

	<pre class="devsite-terminal devsite-click-to-copy">
	dd if=kernel bs=1 skip=$(LC_ALL=C grep -a -b -o $'\x1f\x8b\x08\x00\x00\x00\x00\x00' kernel \| cut -d ':' -f 1) \| zgrep -a 'Linux version'
	</pre>

	<p>For Nexus 5 (hammerhead), the command is:</p>
	<pre class="devsite-terminal devsite-click-to-copy">
	dd if=zImage-dtb bs=1 skip=$(LC_ALL=C od -Ad -x -w2 zImage-dtb \| grep 8b1f \| cut -d ' ' -f1 \| head -1) \| zgrep -a 'Linux version'
	</pre>


	<h2 id="downloading-sources">Downloading sources</h2>
	<p>Download the source for the kernel you want to build using the appropriate
	<code>git clone</code> command. For example, the following command clones the
	<code>common</code> kernel, a generic, customizable kernel:</p>
	<pre class="devsite-terminal devsite-click-to-copy">
	git clone https://android.googlesource.com/kernel/common
	</pre>

	<p>A full list of the kernel projects can be found in the
	<a href="https://android.googlesource.com/kernel">Kernel</a> directory. Below
	are some of the commonly used kernels and their respective <code>git clone</code>
	commands.</p>

	<p>The <code>exynos</code> project has the kernel sources for Nexus 10, and can
	be used as a starting point for work on Samsung Exynos chipsets.</p>
	<pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/exynos</pre>

	<p>The <code>goldfish</code> project contains the kernel sources for the
	emulated platforms.</p>
	<pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/goldfish</pre>

	<p>The <code>hikey-linaro</code> project is used for HiKey reference boards,
	and can be used as a starting point for work on HiSilicon 620 chipsets.</p>
	<pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/hikey-linaro</pre>

	<p>The <code>msm</code> project has the sources for ADP1, ADP2, Nexus One,
	Nexus 4, Nexus 5, Nexus 6, Nexus 5X, Nexus 6P, Nexus 7 (2013), Pixel, and
	Pixel XL, and can be used as a starting point for work on Qualcomm MSM chipsets.</p>
	<pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/msm</pre>

	<p>The <code>omap</code> project is used for PandaBoard and Galaxy Nexus, and
	can be used as a starting point for work on TI OMAP chipsets.</p>
	<pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/omap</pre>

	<p>The <code>samsung</code> project is used for Nexus S, and can be used as a
	starting point for work on Samsung Hummingbird chipsets.</p>
	<pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/samsung</pre>

	<p>The <code>tegra</code> project is for Xoom, Nexus 7 (2012), Nexus 9, and can
	be used as a starting point for work on NVIDIA Tegra chipsets.</p>
	<pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/tegra</pre>

	<p>The <code>x86_64</code> project has the kernel sources for Nexus Player, and
	can be used as a starting point for work on Intel x86_64 chipsets.</p>
	<pre class="devsite-terminal devsite-click-to-copy">git clone https://android.googlesource.com/kernel/x86_64</pre>

	<h2 id="building">Building the kernel manually</h2>
	<p>When you know the last commit message for a kernel and have successfully
	downloaded the kernel source and prebuilt gcc, you are ready to build the
	kernel. The following build commands use the hikey kernel:</p>
	<pre class="devsite-click-to-copy">
	<code class="devsite-terminal">export ARCH=arm64</code>
	<code class="devsite-terminal">export CROSS_COMPILE=aarch64-linux-android-</code>
	<code class="devsite-terminal">cd hikey-linaro</code>
	<code class="devsite-terminal">git checkout -b android-hikey-linaro-4.1 origin/android-hikey-linaro-4.1</code>
	<code class="devsite-terminal">make hikey_defconfig</code>
	<code class="devsite-terminal">make</code>
	</pre>

	<p>To build a different kernel, simply replace <code>hikey-linaro</code> with
	the name of the kernel you want to build.</p>

	<p>The image outputs to the <code>arch/arm64/boot/Image</code> directory; the
	kernel binary outputs to the
	<code>arch/arm64/boot/dts/hisilicon/hi6220-hikey.dtb</code> fle. Copy the
	<code>Image</code> directory and the <code>hi6220-hikey.dtb</code> file to the
	<code>hikey-kernel</code> directory.</p>

	<p>Alternatively, you can include the <code>TARGET_PREBUILT_KERNEL</code>
	variable while using <code>make bootimage</code> (or any other <code>make</code>
	command line that builds a boot image). This variable is supported by all
	devices as it is set up via <code>device/common/populate-new-device.sh</code>.
	For example:</p>

	<pre class="devsite-terminal devsite-click-to-copy">
	export TARGET_PREBUILT_KERNEL=$your_kernel_path/arch/arm/boot/zImage-dtb
	</pre>

	<p class="note"><strong>Note:</strong> Kernel names differ by device. To locate
	the correct filename for your kernel, refer to
	<code>device/<var>VENDOR</var>/<var>NAME</var></code> in the kernel source.</p>


	<h2 id="building-b1c1">Building Pixel 3 (blueline) and Pixel 3 XL (crosshatch) kernels</h2>

	<p>For Pixel 3 and Pixel 3 XL, the kernel source is separated into multiple
	projects. Use <a href="/setup/develop/repo#init">repo</a> to download the
	kernel source for the appropriate branch (as of this writing, <code><var>VERSION</var></code> should be
	<code>4.9-pie-qpr1</code>):</p>

	<pre class="devsite-terminal devsite-click-to-copy">repo init -u https://android.googlesource.com/platform/manifest -b android-msm-bluecross-$<var>VERSION</var></pre>
	<pre class="devsite-terminal devsite-click-to-copy">repo sync</pre>

	<p>Then build the kernel with:</p>

	<pre class="devsite-terminal devsite-click-to-copy">sh build/build.sh</pre>
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