Documentation Kernel Beat

Linux Kernel

Fedora 25 includes the following kernel builds:

• Native kernel, for use in most systems. Configured sources are available in the kernel-devel package.

• The kernel-PAE, for use in 32-bit x86 systems with more than 4GB of RAM, or with CPUs that have a NX (No eXecute) feature. This kernel support both uniprocessor and multi-processor systems. Configured sources are available in the kernel-PAE-devel package.

• Debugging kernel, for use in debugging some kernel issues. Configured sources are available in the kernel-debug-devel package.

You may install kernel headers for all four kernel flavors at the same time. The files are installed in the /usr/src/kernels/<version>[-PAE|-xen|-kdump] -<arch>/ tree. Use the following command:

su -c 'yum install kernel{,-PAE,-xen,-kdump}-devel'

Select one or more of these flavors, separated by commas and no spaces, as appropriate. Enter the root password when prompted.

x86 Kernel Includes Kdump
Both the x86_64 and the i686 kernels are relocatable, so they no longer require a separate kernel for kdump capability. PPC64 still requires a separate kdump kernel.

x86 Kernel Includes Paravirtualization
Both the x86_64 and the i686 kernels contain paravirt_ops support, so they no longer require a separate kernel for running under a Xen hypervisor.

Default Kernel Provides SMP
There is no separate SMP kernel available for Fedora on i386, x86_64, and ppc64. Multiprocessor support is provided by the native kernel.

PowerPC Kernel Support
There is no support for Xen or kdump for the PowerPC architecture in Fedora. 32-bit PowerPC still has a separate SMP kernel.

Preparing for Kernel Development

Fedora 25 does not include the kernel-source package provided by older versions since only the kernel-devel package is required now to build external modules. Configured sources are available, as described above.

Custom Kernel Building
For information on kernel development and working with custom kernels, refer to http://fedoraproject.org/wiki/Building_a_custom_kernel.

Reporting Bugs

Refer to http://kernel.org/pub/linux/docs/lkml/reporting-bugs.html for information on reporting bugs in the Linux kernel. You may also use http://bugzilla.redhat.com for reporting bugs that are specific to Fedora. -->