Chapter 36. Manually Upgrading the Kernel330Notekernel-hugemem is required for memory configurations higher than 16 GB.• PAE (Physical Address Extension) or 3 level paging on x86 processors that support PAE• Support for multiple processors• 4GB/4GB split — 4GB of virtual address space for the kernel and almost 4GB for each userprocess on x86 systems• kernel-hugemem-devel — Contains the kernel headers and makefiles sufficient to build modulesagainst the kernel-hugemem package.• kernel-smp — Contains the kernel for multi-processor systems. The following are the keyfeatures:• Multi-processor support• Support for more than 4 GB of RAM (up to 16 GB for x86)• PAE (Physical Address Extension) or 3 level paging on x86 processors that support PAE• kernel-smp-devel — Contains the kernel headers and makefiles sufficient to build modulesagainst the kernel-smp package.• kernel-utils — Contains utilities that can be used to control the kernel or system hardware.• kernel-doc — Contains documentation files from the kernel source. Various portions of theLinux kernel and the device drivers shipped with it are documented in these files. Installation of thispackage provides a reference to the options that can be passed to Linux kernel modules at loadtime.By default, these files are placed in the /usr/share/doc/kernel-doc-/ directory.NoteThe kernel-source package has been removed and replaced with an RPM that canonly be retrieved from Red Hat Network. This *.src.rpm must then be rebuilt locallyusing the rpmbuild command. Refer to the latest distribution Release Notes, includingall updates, at https://www.redhat.com/docs/manuals/enterprise/ for more information onobtaining and installing the kernel source package.36.2. Preparing to UpgradeBefore upgrading the kernel, take a few precautionary steps. The first step is to make sure workingboot media exists for the system in case a problem occurs. If the boot loader is not configured properlyto boot the new kernel, the system cannot be booted into Red Hat Enterprise Linux without workingboot media.
