Dynamic Kernel Module Support: From Theory to Practice

DKMS is a framework which allows individual kernel modules to be upgraded without changing your whole kernel. Its primary audience is fourfold: system administrators who want to update a single device driver rather than wait for a new kernel from elsewhere with it included; distribution maintainers, who want to release a single targeted bugfix in between larger scheduled updates; system manufacturers who need single modules changed to support new hardware or to fix bugs, but do not wish to test whole new kernels; and driver developers, who must provide updated device drivers for testing and general use on a wide variety of kernels, as well as submit drivers to kernel.org.

Since OLS2003, DKMS has gone from good idea to deployed and used. Based on end user feedback, additional features have been added: precompiled module tarball support to speed factory installation; driver disks for Red Hat distributions; 2.6 kernel support; SuSE kernel support. Planned features include cross-architecture build support and additional distribution driver disk methods.

In addition to an overview of DKMS and its features, we present case studies of DKMS in action as deployed by Dell in launching Red Hat Enterprise Linux 3, and explain how to make your own dkms.conf file to DKMS-ify your kernel module source.

Authors: Gary Lerhaupt and Matt Domsch