lfs-book/chapter05/kernel-exp.xml

<sect2>
<title>Command explanations</title>

<para><userinput>make mrproper:</userinput> This will ensure that the kernel
tree is absolutely clean.  We do this because the kernel team recommend
that this is done prior to <emphasis>each</emphasis> kernel compilation,
and that we shouldn't rely on the source tree being automatically clean
after untarring.</para>

<para><userinput>yes "" | make config:</userinput> This runs make config and
answers with the default answer to every question the config script asks 
the user (it does this by simply doing the equivalent of hitting the
Enter key, thus accepting the default Y and N answers to the questions). 
We're not configuring the real kernel here, we just need to have some sort 
of configure file created so that we can run make dep next that will 
create a few header files in <filename>include/linux</filename>, like
version.h, among others, that we will need to compile Glibc and other
packages later in chroot.</para>

<para><userinput>make dep:</userinput> make dep checks dependencies and sets
up the dependencies file. We don't really care about the dependency
checks, but what we do care about is that make dep creates those
aforementioned files in <filename>include/linux</filename> we will be
needing later on.</para>

<para><userinput>mkdir $LFS/usr/include/asm</userinput>
and <userinput>cp include/asm/* $LFS/usr/include/asm</userinput>:
This copies the platform-specific assembler kernel header files to
<filename>$LFS/usr/include/asm</filename>.</para>

<para><userinput>cp -R include/linux $LFS/usr/include</userinput>:
This command copies the cross-platform kernel header files to
<filename>$LFS/usr/include</filename>.</para>

</sect2>