kernel-source package provides patch applied source code:
rpm2cpio kernel-source-2.4.21-27.0.2.1.7.EL.i386.rpm | cpio -idmv
The src rpm does provide the base source and patches:
rpm -i kernel-2.4.21-27.0.2.1.7.EL.src.rpm
/>> This installs the base kernel and the *.patch separately
cd /usr/src/redhat/SPECS/
rpmbuild -bp kernel-2.4.ora-27.1.7.EL.spec
If Architecture is not included: i386
rpmbuild -bp –target i686 kernel-2.4.ora-27.1.7.EL.spec
/>> This installs the patches and provides the actual kernel tree
cd ../BUILD/kernel-2.4.21/linux-2.4.21