Build
Download xen: http://www.xen.org/download/
The combined source distribution is a good idea.
Untar it somewhere
$ tar -zxvf xen-3.4.0.tar.gz
Go in there and prep the kernels
$ cd xen-3.4.0 $ make prep-kernels KERNELS="linux-2.6-xen0 linux-2.6-xenU"
If you don't use the prefix "linux-2.6-xen" xen will ignore it.
Do any configuration necessary for those kernels
$ cd build-linux-2.6.18-xen0_x86_32 ...do whatever... $ cd ..
Then build all the parts of xen. Supposedly 'make world' will do this but it usually fails for me.
$ make xen $ make install-xen $ make tools $ make install-tools $ cd build-linux-... $ make $ make modules_install $ make install