Kernel Building

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Note

it is recommended that you build an RPM (Rebuilding OLPC kernel) unless you are already familiar with kernel development!

Building an OLPC kernel

After obtaining the OLPC source (and if desired, making changes), the following steps can be taken to build a kernel on any Fedora Core 6 machine:

make oldconfig
make
make modules_install  # as root
tar zcvf kern.tar.gz arch/i386/boot/bzImage System.map /lib/modules/$VERS

Warning!

this needs root and will trash your /lib/modules, if you happen to already have same version. Use "make INSTALL_MOD_PATH=/somewhere modules_install" if you want to avoid using root).

Note

for current olpc-2.6/master (2.6.26-rcX) x86 must be used instead of i386 in these instructions.

Replace $VERS above with the proper kernel version that has been built.

Assuming everything builds correctly, you will be left with kern.tar.gz. This can be copied over to an XO laptop, and the following steps will install the kernel (again, replacing $VERS with the kernel version):

cd /
tar zxvf .../kern.tar.gz
mv System.map /versions/boot/current/boot/System.map-$VERS
mv arch/i386/boot/bzImage /versions/boot/current/boot/vmlinuz-$VERS
ln -sf /versions/boot/current/boot/vmlinuz-$VERS /versions/boot/current/boot/vmlinuz

If not booting off NAND, you'll probably want to skip the /versions/boot/current/ prefix on the paths above. A limited number of kernel modules are required by the ramdisk during the boot process; if you need to update the ramdisk, these additional steps are also necessary:

# mkdir /tmp/X ; cd /tmp/X
# zcat /versions/boot/current/boot/olpcrd.img | cpio -i
# rm -r lib/modules
# cp -r /lib/modules lib/
# find . -print | cpio -H newc -o | gzip -9 > /versions/boot/current/boot/olpcrd.img