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+.. _kernel_docs:
+
+Index of Documentation for People Interested in Writing and/or Understanding the Linux Kernel
+=============================================================================================
+
+ Juan-Mariano de Goyeneche <jmseyas@dit.upm.es>
+
+The need for a document like this one became apparent in the
+linux-kernel mailing list as the same questions, asking for pointers
+to information, appeared again and again.
+
+Fortunately, as more and more people get to GNU/Linux, more and more
+get interested in the Kernel. But reading the sources is not always
+enough. It is easy to understand the code, but miss the concepts, the
+philosophy and design decisions behind this code.
+
+Unfortunately, not many documents are available for beginners to
+start. And, even if they exist, there was no "well-known" place which
+kept track of them. These lines try to cover this lack. All documents
+available on line known by the author are listed, while some reference
+books are also mentioned.
+
+PLEASE, if you know any paper not listed here or write a new document,
+send me an e-mail, and I'll include a reference to it here. Any
+corrections, ideas or comments are also welcomed.
+
+The papers that follow are listed in no particular order. All are
+cataloged with the following fields: the document's "Title", the
+"Author"/s, the "URL" where they can be found, some "Keywords" helpful
+when searching for specific topics, and a brief "Description" of the
+Document.
+
+Enjoy!
+
+.. note::
+
+ The documents on each section of this document are ordered by its
+ published date, from the newest to the oldest.
+
+Docs at the Linux Kernel tree
+-----------------------------
+
+The Sphinx books should be built with ``make {htmldocs | pdfdocs | epubdocs}``.
+
+ * Name: **linux/Documentation**
+
+ :Author: Many.
+ :Location: Documentation/
+ :Keywords: text files, Sphinx.
+ :Description: Documentation that comes with the kernel sources,
+ inside the Documentation directory. Some pages from this document
+ (including this document itself) have been moved there, and might
+ be more up to date than the web version.
+
+On-line docs
+------------
+
+ * Title: **Linux Kernel Mailing List Glossary**
+
+ :Author: various
+ :URL: https://kernelnewbies.org/KernelGlossary
+ :Date: rolling version
+ :Keywords: glossary, terms, linux-kernel.
+ :Description: From the introduction: "This glossary is intended as
+ a brief description of some of the acronyms and terms you may hear
+ during discussion of the Linux kernel".
+
+ * Title: **Tracing the Way of Data in a TCP Connection through the Linux Kernel**
+
+ :Author: Richard Sailer
+ :URL: https://archive.org/details/linux_kernel_data_flow_short_paper
+ :Date: 2016
+ :Keywords: Linux Kernel Networking, TCP, tracing, ftrace
+ :Description: A seminar paper explaining ftrace and how to use it for
+ understanding linux kernel internals,
+ illustrated at tracing the way of a TCP packet through the kernel.
+ :Abstract: *This short paper outlines the usage of ftrace a tracing framework
+ as a tool to understand a running Linux system.
+ Having obtained a trace-log a kernel hacker can read and understand
+ source code more determined and with context.
+ In a detailed example this approach is demonstrated in tracing
+ and the way of data in a TCP Connection through the kernel.
+ Finally this trace-log is used as base for more a exact conceptual
+ exploration and description of the Linux TCP/IP implementation.*
+
+ * Title: **On submitting kernel Patches**
+
+ :Author: Andi Kleen
+ :URL: http://halobates.de/on-submitting-kernel-patches.pdf
+ :Date: 2008
+ :Keywords: patches, review process, types of submissions, basic rules, case studies
+ :Description: This paper gives several experience values on what types of patches
+ there are and how likley they get merged.
+ :Abstract:
+ [...]. This paper examines some common problems for
+ submitting larger changes and some strategies to avoid problems.
+
+ * Title: **Linux Device Drivers, Third Edition**
+
+ :Author: Jonathan Corbet, Alessandro Rubini, Greg Kroah-Hartman
+ :URL: https://lwn.net/Kernel/LDD3/
+ :Date: 2005
+ :Description: A 600-page book covering the (2.6.10) driver
+ programming API and kernel hacking in general. Available under the
+ Creative Commons Attribution-ShareAlike 2.0 license.
+ :note: You can also :ref:`purchase a copy from O'Reilly or elsewhere <ldd3_published>`.
+
+ * Title: **Writing an ALSA Driver**
+
+ :Author: Takashi Iwai <tiwai@suse.de>
+ :URL: http://www.alsa-project.org/~iwai/writing-an-alsa-driver/index.html
+ :Date: 2005
+ :Keywords: ALSA, sound, soundcard, driver, lowlevel, hardware.
+ :Description: Advanced Linux Sound Architecture for developers,
+ both at kernel and user-level sides. ALSA is the Linux kernel
+ sound architecture in the 2.6 kernel version.
+
+ * Title: **Linux PCMCIA Programmer's Guide**
+
+ :Author: David Hinds.
+ :URL: http://pcmcia-cs.sourceforge.net/ftp/doc/PCMCIA-PROG.html
+ :Date: 2003
+ :Keywords: PCMCIA.
+ :Description: "This document describes how to write kernel device
+ drivers for the Linux PCMCIA Card Services interface. It also
+ describes how to write user-mode utilities for communicating with
+ Card Services.
+
+ * Title: **Linux Kernel Module Programming Guide**
+
+ :Author: Ori Pomerantz.
+ :URL: https://tldp.org/LDP/lkmpg/2.6/html/index.html
+ :Date: 2001
+ :Keywords: modules, GPL book, /proc, ioctls, system calls,
+ interrupt handlers .
+ :Description: Very nice 92 pages GPL book on the topic of modules
+ programming. Lots of examples.
+
+ * Title: **Global spinlock list and usage**
+
+ :Author: Rick Lindsley.
+ :URL: http://lse.sourceforge.net/lockhier/global-spin-lock
+ :Date: 2001
+ :Keywords: spinlock.
+ :Description: This is an attempt to document both the existence and
+ usage of the spinlocks in the Linux 2.4.5 kernel. Comprehensive
+ list of spinlocks showing when they are used, which functions
+ access them, how each lock is acquired, under what conditions it
+ is held, whether interrupts can occur or not while it is held...
+
+ * Title: **A Linux vm README**
+
+ :Author: Kanoj Sarcar.
+ :URL: http://kos.enix.org/pub/linux-vmm.html
+ :Date: 2001
+ :Keywords: virtual memory, mm, pgd, vma, page, page flags, page
+ cache, swap cache, kswapd.
+ :Description: Telegraphic, short descriptions and definitions
+ relating the Linux virtual memory implementation.
+
+ * Title: **Video4linux Drivers, Part 1: Video-Capture Device**
+
+ :Author: Alan Cox.
+ :URL: http://www.linux-mag.com/id/406
+ :Date: 2000
+ :Keywords: video4linux, driver, video capture, capture devices,
+ camera driver.
+ :Description: The title says it all.
+
+ * Title: **Video4linux Drivers, Part 2: Video-capture Devices**
+
+ :Author: Alan Cox.
+ :URL: http://www.linux-mag.com/id/429
+ :Date: 2000
+ :Keywords: video4linux, driver, video capture, capture devices,
+ camera driver, control, query capabilities, capability, facility.
+ :Description: The title says it all.
+
+ * Title: **Linux IP Networking. A Guide to the Implementation and Modification of the Linux Protocol Stack.**
+
+ :Author: Glenn Herrin.
+ :URL: http://www.cs.unh.edu/cnrg/gherrin
+ :Date: 2000
+ :Keywords: network, networking, protocol, IP, UDP, TCP, connection,
+ socket, receiving, transmitting, forwarding, routing, packets,
+ modules, /proc, sk_buff, FIB, tags.
+ :Description: Excellent paper devoted to the Linux IP Networking,
+ explaining anything from the kernel's to the user space
+ configuration tools' code. Very good to get a general overview of
+ the kernel networking implementation and understand all steps
+ packets follow from the time they are received at the network
+ device till they are delivered to applications. The studied kernel
+ code is from 2.2.14 version. Provides code for a working packet
+ dropper example.
+
+ * Title: **How To Make Sure Your Driver Will Work On The Power Macintosh**
+
+ :Author: Paul Mackerras.
+ :URL: http://www.linux-mag.com/id/261
+ :Date: 1999
+ :Keywords: Mac, Power Macintosh, porting, drivers, compatibility.
+ :Description: The title says it all.
+
+ * Title: **An Introduction to SCSI Drivers**
+
+ :Author: Alan Cox.
+ :URL: http://www.linux-mag.com/id/284
+ :Date: 1999
+ :Keywords: SCSI, device, driver.
+ :Description: The title says it all.
+
+ * Title: **Advanced SCSI Drivers And Other Tales**
+
+ :Author: Alan Cox.
+ :URL: http://www.linux-mag.com/id/307
+ :Date: 1999
+ :Keywords: SCSI, device, driver, advanced.
+ :Description: The title says it all.
+
+ * Title: **Writing Linux Mouse Drivers**
+
+ :Author: Alan Cox.
+ :URL: http://www.linux-mag.com/id/330
+ :Date: 1999
+ :Keywords: mouse, driver, gpm.
+ :Description: The title says it all.
+
+ * Title: **More on Mouse Drivers**
+
+ :Author: Alan Cox.
+ :URL: http://www.linux-mag.com/id/356
+ :Date: 1999
+ :Keywords: mouse, driver, gpm, races, asynchronous I/O.
+ :Description: The title still says it all.
+
+ * Title: **Writing Video4linux Radio Driver**
+
+ :Author: Alan Cox.
+ :URL: http://www.linux-mag.com/id/381
+ :Date: 1999
+ :Keywords: video4linux, driver, radio, radio devices.
+ :Description: The title says it all.
+
+ * Title: **I/O Event Handling Under Linux**
+
+ :Author: Richard Gooch.
+ :URL: https://web.mit.edu/~yandros/doc/io-events.html
+ :Date: 1999
+ :Keywords: IO, I/O, select(2), poll(2), FDs, aio_read(2), readiness
+ event queues.
+ :Description: From the Introduction: "I/O Event handling is about
+ how your Operating System allows you to manage a large number of
+ open files (file descriptors in UNIX/POSIX, or FDs) in your
+ application. You want the OS to notify you when FDs become active
+ (have data ready to be read or are ready for writing). Ideally you
+ want a mechanism that is scalable. This means a large number of
+ inactive FDs cost very little in memory and CPU time to manage".
+
+ * Title: **(nearly) Complete Linux Loadable Kernel Modules. The definitive guide for hackers, virus coders and system administrators.**
+
+ :Author: pragmatic/THC.
+ :URL: http://packetstormsecurity.org/docs/hack/LKM_HACKING.html
+ :Date: 1999
+ :Keywords: syscalls, intercept, hide, abuse, symbol table.
+ :Description: Interesting paper on how to abuse the Linux kernel in
+ order to intercept and modify syscalls, make
+ files/directories/processes invisible, become root, hijack ttys,
+ write kernel modules based virus... and solutions for admins to
+ avoid all those abuses.
+ :Notes: For 2.0.x kernels. Gives guidances to port it to 2.2.x
+ kernels.
+
+ * Name: **Linux Virtual File System**
+
+ :Author: Peter J. Braam.
+ :URL: http://www.coda.cs.cmu.edu/doc/talks/linuxvfs/
+ :Date: 1998
+ :Keywords: slides, VFS, inode, superblock, dentry, dcache.
+ :Description: Set of slides, presumably from a presentation on the
+ Linux VFS layer. Covers version 2.1.x, with dentries and the
+ dcache.
+
+ * Title: **The Venus kernel interface**
+
+ :Author: Peter J. Braam.
+ :URL: http://www.coda.cs.cmu.edu/doc/html/kernel-venus-protocol.html
+ :Date: 1998
+ :Keywords: coda, filesystem, venus, cache manager.
+ :Description: "This document describes the communication between
+ Venus and kernel level file system code needed for the operation
+ of the Coda filesystem. This version document is meant to describe
+ the current interface (version 1.0) as well as improvements we
+ envisage".
+
+ * Title: **Design and Implementation of the Second Extended Filesystem**
+
+ :Author: Rémy Card, Theodore Ts'o, Stephen Tweedie.
+ :URL: https://web.mit.edu/tytso/www/linux/ext2intro.html
+ :Date: 1998
+ :Keywords: ext2, linux fs history, inode, directory, link, devices,
+ VFS, physical structure, performance, benchmarks, ext2fs library,
+ ext2fs tools, e2fsck.
+ :Description: Paper written by three of the top ext2 hackers.
+ Covers Linux filesystems history, ext2 motivation, ext2 features,
+ design, physical structure on disk, performance, benchmarks,
+ e2fsck's passes description... A must read!
+ :Notes: This paper was first published in the Proceedings of the
+ First Dutch International Symposium on Linux, ISBN 90-367-0385-9.
+
+ * Title: **The Linux RAID-1, 4, 5 Code**
+
+ :Author: Ingo Molnar, Gadi Oxman and Miguel de Icaza.
+ :URL: http://www.linuxjournal.com/article.php?sid=2391
+ :Date: 1997
+ :Keywords: RAID, MD driver.
+ :Description: Linux Journal Kernel Korner article.
+ :Abstract: *A description of the implementation of the RAID-1,
+ RAID-4 and RAID-5 personalities of the MD device driver in the
+ Linux kernel, providing users with high performance and reliable,
+ secondary-storage capability using software*.
+
+ * Title: **Linux Kernel Hackers' Guide**
+
+ :Author: Michael K. Johnson.
+ :URL: https://www.tldp.org/LDP/khg/HyperNews/get/khg.html
+ :Date: 1997
+ :Keywords: device drivers, files, VFS, kernel interface, character vs
+ block devices, hardware interrupts, scsi, DMA, access to user memory,
+ memory allocation, timers.
+ :Description: A guide designed to help you get up to speed on the
+ concepts that are not intuitevly obvious, and to document the internal
+ structures of Linux.
+
+ * Title: **Dynamic Kernels: Modularized Device Drivers**
+
+ :Author: Alessandro Rubini.
+ :URL: http://www.linuxjournal.com/article.php?sid=1219
+ :Date: 1996
+ :Keywords: device driver, module, loading/unloading modules,
+ allocating resources.
+ :Description: Linux Journal Kernel Korner article.
+ :Abstract: *This is the first of a series of four articles
+ co-authored by Alessandro Rubini and Georg Zezchwitz which present
+ a practical approach to writing Linux device drivers as kernel
+ loadable modules. This installment presents an introduction to the
+ topic, preparing the reader to understand next month's
+ installment*.
+
+ * Title: **Dynamic Kernels: Discovery**
+
+ :Author: Alessandro Rubini.
+ :URL: http://www.linuxjournal.com/article.php?sid=1220
+ :Date: 1996
+ :Keywords: character driver, init_module, clean_up module,
+ autodetection, mayor number, minor number, file operations,
+ open(), close().
+ :Description: Linux Journal Kernel Korner article.
+ :Abstract: *This article, the second of four, introduces part of
+ the actual code to create custom module implementing a character
+ device driver. It describes the code for module initialization and
+ cleanup, as well as the open() and close() system calls*.
+
+ * Title: **The Devil's in the Details**
+
+ :Author: Georg v. Zezschwitz and Alessandro Rubini.
+ :URL: http://www.linuxjournal.com/article.php?sid=1221
+ :Date: 1996
+ :Keywords: read(), write(), select(), ioctl(), blocking/non
+ blocking mode, interrupt handler.
+ :Description: Linux Journal Kernel Korner article.
+ :Abstract: *This article, the third of four on writing character
+ device drivers, introduces concepts of reading, writing, and using
+ ioctl-calls*.
+
+ * Title: **Dissecting Interrupts and Browsing DMA**
+
+ :Author: Alessandro Rubini and Georg v. Zezschwitz.
+ :URL: https://www.linuxjournal.com/article.php?sid=1222
+ :Date: 1996
+ :Keywords: interrupts, irqs, DMA, bottom halves, task queues.
+ :Description: Linux Journal Kernel Korner article.
+ :Abstract: *This is the fourth in a series of articles about
+ writing character device drivers as loadable kernel modules. This
+ month, we further investigate the field of interrupt handling.
+ Though it is conceptually simple, practical limitations and
+ constraints make this an ''interesting'' part of device driver
+ writing, and several different facilities have been provided for
+ different situations. We also investigate the complex topic of
+ DMA*.
+
+ * Title: **Device Drivers Concluded**
+
+ :Author: Georg v. Zezschwitz.
+ :URL: https://www.linuxjournal.com/article.php?sid=1287
+ :Date: 1996
+ :Keywords: address spaces, pages, pagination, page management,
+ demand loading, swapping, memory protection, memory mapping, mmap,
+ virtual memory areas (VMAs), vremap, PCI.
+ :Description: Finally, the above turned out into a five articles
+ series. This latest one's introduction reads: "This is the last of
+ five articles about character device drivers. In this final
+ section, Georg deals with memory mapping devices, beginning with
+ an overall description of the Linux memory management concepts".
+
+ * Title: **Network Buffers And Memory Management**
+
+ :Author: Alan Cox.
+ :URL: https://www.linuxjournal.com/article.php?sid=1312
+ :Date: 1996
+ :Keywords: sk_buffs, network devices, protocol/link layer
+ variables, network devices flags, transmit, receive,
+ configuration, multicast.
+ :Description: Linux Journal Kernel Korner.
+ :Abstract: *Writing a network device driver for Linux is fundamentally
+ simple---most of the complexity (other than talking to the
+ hardware) involves managing network packets in memory*.
+
+ * Title: **Analysis of the Ext2fs structure**
+
+ :Author: Louis-Dominique Dubeau.
+ :URL: https://teaching.csse.uwa.edu.au/units/CITS2002/fs-ext2/
+ :Date: 1994
+ :Keywords: ext2, filesystem, ext2fs.
+ :Description: Description of ext2's blocks, directories, inodes,
+ bitmaps, invariants...
+
+Published books
+---------------
+
+ * Title: **Linux Treiber entwickeln**
+
+ :Author: Jürgen Quade, Eva-Katharina Kunst
+ :Publisher: dpunkt.verlag
+ :Date: Oct 2015 (4th edition)
+ :Pages: 688
+ :ISBN: 978-3-86490-288-8
+ :Note: German. The third edition from 2011 is
+ much cheaper and still quite up-to-date.
+
+ * Title: **Linux Kernel Networking: Implementation and Theory**
+
+ :Author: Rami Rosen
+ :Publisher: Apress
+ :Date: December 22, 2013
+ :Pages: 648
+ :ISBN: 978-1430261964
+
+ * Title: **Embedded Linux Primer: A practical Real-World Approach, 2nd Edition**
+
+ :Author: Christopher Hallinan
+ :Publisher: Pearson
+ :Date: November, 2010
+ :Pages: 656
+ :ISBN: 978-0137017836
+
+ * Title: **Linux Kernel Development, 3rd Edition**
+
+ :Author: Robert Love
+ :Publisher: Addison-Wesley
+ :Date: July, 2010
+ :Pages: 440
+ :ISBN: 978-0672329463
+
+ * Title: **Essential Linux Device Drivers**
+
+ :Author: Sreekrishnan Venkateswaran
+ :Published: Prentice Hall
+ :Date: April, 2008
+ :Pages: 744
+ :ISBN: 978-0132396554
+
+.. _ldd3_published:
+
+ * Title: **Linux Device Drivers, 3rd Edition**
+
+ :Authors: Jonathan Corbet, Alessandro Rubini, and Greg Kroah-Hartman
+ :Publisher: O'Reilly & Associates
+ :Date: 2005
+ :Pages: 636
+ :ISBN: 0-596-00590-3
+ :Notes: Further information in
+ http://www.oreilly.com/catalog/linuxdrive3/
+ PDF format, URL: https://lwn.net/Kernel/LDD3/
+
+ * Title: **Linux Kernel Internals**
+
+ :Author: Michael Beck
+ :Publisher: Addison-Wesley
+ :Date: 1997
+ :ISBN: 0-201-33143-8 (second edition)
+
+ * Title: **Programmation Linux 2.0 API systeme et fonctionnement du noyau**
+
+ :Author: Remy Card, Eric Dumas, Franck Mevel
+ :Publisher: Eyrolles
+ :Date: 1997
+ :Pages: 520
+ :ISBN: 2-212-08932-5
+ :Notes: French
+
+ * Title: **The Design and Implementation of the 4.4 BSD UNIX Operating System**
+
+ :Author: Marshall Kirk McKusick, Keith Bostic, Michael J. Karels,
+ John S. Quarterman
+ :Publisher: Addison-Wesley
+ :Date: 1996
+ :ISBN: 0-201-54979-4
+
+ * Title: **Unix internals -- the new frontiers**
+
+ :Author: Uresh Vahalia
+ :Publisher: Prentice Hall
+ :Date: 1996
+ :Pages: 600
+ :ISBN: 0-13-101908-2
+
+ * Title: **Programming for the real world - POSIX.4**
+
+ :Author: Bill O. Gallmeister
+ :Publisher: O'Reilly & Associates, Inc
+ :Date: 1995
+ :Pages: 552
+ :ISBN: I-56592-074-0
+ :Notes: Though not being directly about Linux, Linux aims to be
+ POSIX. Good reference.
+
+ * Title: **UNIX Systems for Modern Architectures: Symmetric Multiprocessing and Caching for Kernel Programmers**
+
+ :Author: Curt Schimmel
+ :Publisher: Addison Wesley
+ :Date: June, 1994
+ :Pages: 432
+ :ISBN: 0-201-63338-8
+
+ * Title: **The Design and Implementation of the 4.3 BSD UNIX Operating System**
+
+ :Author: Samuel J. Leffler, Marshall Kirk McKusick, Michael J
+ Karels, John S. Quarterman
+ :Publisher: Addison-Wesley
+ :Date: 1989 (reprinted with corrections on October, 1990)
+ :ISBN: 0-201-06196-1
+
+ * Title: **The Design of the UNIX Operating System**
+
+ :Author: Maurice J. Bach
+ :Publisher: Prentice Hall
+ :Date: 1986
+ :Pages: 471
+ :ISBN: 0-13-201757-1
+
+Miscellaneous
+-------------
+
+ * Name: **Cross-Referencing Linux**
+
+ :URL: https://elixir.bootlin.com/
+ :Keywords: Browsing source code.
+ :Description: Another web-based Linux kernel source code browser.
+ Lots of cross references to variables and functions. You can see
+ where they are defined and where they are used.
+
+ * Name: **Linux Weekly News**
+
+ :URL: https://lwn.net
+ :Keywords: latest kernel news.
+ :Description: The title says it all. There's a fixed kernel section
+ summarizing developers' work, bug fixes, new features and versions
+ produced during the week. Published every Thursday.
+
+ * Name: **The home page of Linux-MM**
+
+ :Author: The Linux-MM team.
+ :URL: https://linux-mm.org/
+ :Keywords: memory management, Linux-MM, mm patches, TODO, docs,
+ mailing list.
+ :Description: Site devoted to Linux Memory Management development.
+ Memory related patches, HOWTOs, links, mm developers... Don't miss
+ it if you are interested in memory management development!
+
+ * Name: **Kernel Newbies IRC Channel and Website**
+
+ :URL: https://www.kernelnewbies.org
+ :Keywords: IRC, newbies, channel, asking doubts.
+ :Description: #kernelnewbies on irc.oftc.net.
+ #kernelnewbies is an IRC network dedicated to the 'newbie'
+ kernel hacker. The audience mostly consists of people who are
+ learning about the kernel, working on kernel projects or
+ professional kernel hackers that want to help less seasoned kernel
+ people.
+ #kernelnewbies is on the OFTC IRC Network.
+ Try irc.oftc.net as your server and then /join #kernelnewbies.
+ The kernelnewbies website also hosts articles, documents, FAQs...
+
+ * Name: **linux-kernel mailing list archives and search engines**
+
+ :URL: http://vger.kernel.org/vger-lists.html
+ :URL: http://www.uwsg.indiana.edu/hypermail/linux/kernel/index.html
+ :URL: http://groups.google.com/group/mlist.linux.kernel
+ :Keywords: linux-kernel, archives, search.
+ :Description: Some of the linux-kernel mailing list archivers. If
+ you have a better/another one, please let me know.
+
+-------
+
+Document last updated on Tue 2016-Sep-20
+
+This document is based on:
+ https://www.dit.upm.es/~jmseyas/linux/kernel/hackers-docs.html