Linux kernel interfaces - Revision history

Stevebroshar: Describe classifications up front and consistently

2025-04-27T20:59:30Z

Describe classifications up front and consistently

← Previous revision		Revision as of 20:59, 27 April 2025
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	{{Short description\|~~An overview and comparison of the~~ Linux kernel ~~API~~ and ~~ABI.~~}}		{{Short description\|Linux kernel APIs and ABIs}}
	{{essay-like\|date=July 2014}}		{{essay-like\|date=July 2014}}

	[[File:Linux kernel interfaces.svg\|thumb\|upright=1.5\|Linux API, Linux ABI, and in-kernel APIs and ABIs]]		[[File:Linux kernel interfaces.svg\|thumb\|upright=1.5\|Linux API, Linux ABI, and in-kernel APIs and ABIs]]

	The [[Linux kernel]] provides multiple interfaces to [[User space and kernel space\|user-space and kernel-mode]] code ~~that~~ ~~are~~ ~~used~~ ~~for~~ ~~varying~~ ~~purposes~~ ~~and~~ ~~that~~ ~~have~~ ~~varying~~ ~~properties~~ ~~by design. There are two types of~~ [[application ~~programming~~ interface]] (~~API~~) in ~~the~~ ~~Linux~~ ~~kernel:~~ kernel–user space ~~and~~ kernel-internal.		The [[Linux kernel]] provides multiple interfaces to [[User space and kernel space\|user-space and kernel-mode]] code. The interfaces can be classified as either [[application programming interface]] (API) or [[application binary interface]] (ABI), and they can be classified as either kernel–user space or kernel-internal.

	== {{Anchor\|Linux API}}Linux API ==		== {{Anchor\|Linux API}}Linux API ==
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	== Linux ABI ==		== Linux ABI ==
	{{Expert needed\|free and open-source software\|ex2=software\|ex3=computing\|reason=This section mostly ignores the kernel-userspace ABI (that is very real and important thing) and jumps into userspace-to-userspace APIs\|date=February 2018}}		{{Expert needed\|free and open-source software\|ex2=software\|ex3=computing\|reason=This section mostly ignores the kernel-userspace ABI (that is very real and important thing) and jumps into userspace-to-userspace APIs\|date=February 2018}}
	[[File:Linux API and Linux ABI.svg\|thumb\|upright=1.5\|The Linux API and ~~the Linux [[Application binary interface\|~~ABI]] ]]		[[File:Linux API and Linux ABI.svg\|thumb\|upright=1.5\|The Linux API and ABI ]]
	{{Main article\|x32 ABI\|Linux Standard Base}}		{{Main article\|x32 ABI\|Linux Standard Base}}

	The Linux ~~[[application binary interface]] (~~ABI) is a kernel–user space ABI. As ABI is a [[machine code]] interface, the Linux ABI is bound to the [[instruction set]]. Defining a useful ABI and keeping it stable is less the responsibility of the Linux kernel developers or of the developers of the GNU C Library, and more the task for [[Linux distribution]]s and [[independent software vendor]]s (ISVs) who wish to sell and provide support for their proprietary software as binaries only for such a single Linux ABI, as opposed to supporting multiple Linux ABIs.		The Linux ABI is a kernel–user space ABI. As ABI is a [[machine code]] interface, the Linux ABI is bound to the [[instruction set]]. Defining a useful ABI and keeping it stable is less the responsibility of the Linux kernel developers or of the developers of the GNU C Library, and more the task for [[Linux distribution]]s and [[independent software vendor]]s (ISVs) who wish to sell and provide support for their proprietary software as binaries only for such a single Linux ABI, as opposed to supporting multiple Linux ABIs.

	An ABI has to be defined for every instruction set, such as [[x86]], [[x86-64]], [[MIPS architecture\|MIPS]], [[ARMv7-A]] (32-Bit), [[ARMv8-A]] (64-Bit), etc. with the [[endianness]], if both are supported.		An ABI has to be defined for every instruction set, such as [[x86]], [[x86-64]], [[MIPS architecture\|MIPS]], [[ARMv7-A]] (32-Bit), [[ARMv8-A]] (64-Bit), etc. with the [[endianness]], if both are supported.

Stevebroshar: uses dash later so do same in intro

2025-04-27T20:53:12Z

uses dash later so do same in intro

← Previous revision		Revision as of 20:53, 27 April 2025
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	[[File:Linux kernel interfaces.svg\|thumb\|upright=1.5\|Linux API, Linux ABI, and in-kernel APIs and ABIs]]		[[File:Linux kernel interfaces.svg\|thumb\|upright=1.5\|Linux API, Linux ABI, and in-kernel APIs and ABIs]]

	The [[Linux kernel]] provides multiple interfaces to [[User space and kernel space\|user-space and kernel-mode]] code that are used for varying purposes and that have varying properties by design. There are two types of [[application programming interface]] (API) in the Linux kernel: kernel–user space and kernel internal.		The [[Linux kernel]] provides multiple interfaces to [[User space and kernel space\|user-space and kernel-mode]] code that are used for varying purposes and that have varying properties by design. There are two types of [[application programming interface]] (API) in the Linux kernel: kernel–user space and kernel-internal.

	== {{Anchor\|Linux API}}Linux API ==		== {{Anchor\|Linux API}}Linux API ==

Stevebroshar: Remove overkill formatting

2025-04-27T20:51:36Z

Remove overkill formatting

← Previous revision		Revision as of 20:51, 27 April 2025
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	[[File:Linux kernel interfaces.svg\|thumb\|upright=1.5\|Linux API, Linux ABI, and in-kernel APIs and ABIs]]		[[File:Linux kernel interfaces.svg\|thumb\|upright=1.5\|Linux API, Linux ABI, and in-kernel APIs and ABIs]]

	The [[Linux kernel]] provides multiple interfaces to user-space and kernel-mode code that are used for varying purposes and that have varying properties by design. There are two types of [[application programming interface]] (API) in the Linux kernel:		The [[Linux kernel]] provides multiple interfaces to [[User space and kernel space\|user-space and kernel-mode]] code that are used for varying purposes and that have varying properties by design. There are two types of [[application programming interface]] (API) in the Linux kernel: kernel–user space and kernel internal.

	# the "kernel–user space" API; and
	# the "kernel internal" API.

	== {{Anchor\|Linux API}}Linux API ==		== {{Anchor\|Linux API}}Linux API ==

Stevebroshar: /* See also */ use Annotated link

2025-04-27T20:48:14Z

Stevebroshar: /* Linux ABI */ get to the point; stay on topic

2025-04-27T20:43:12Z

Linux ABI: get to the point; stay on topic

← Previous revision		Revision as of 20:43, 27 April 2025
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	{{Main article\|x32 ABI\|Linux Standard Base}}		{{Main article\|x32 ABI\|Linux Standard Base}}

	The ~~term~~ Linux ~~ABI refers to a kernel–user space ABI. The~~ [[application binary interface]] ~~refers~~ to ~~the~~ ~~compiled~~ ~~binaries,~~ in [[machine code]]. ~~Any~~ ~~such~~ ABI is ~~therefore~~ bound to the [[instruction set]]. Defining a useful ABI and keeping it stable is less the responsibility of the Linux kernel developers or of the developers of the GNU C Library, and more the task for [[Linux distribution]]s and [[independent software vendor]]s (ISVs) who wish to sell and provide support for their proprietary software as binaries only for such a single Linux ABI, as opposed to supporting multiple Linux ABIs.		The Linux [[application binary interface]] (ABI) is a kernel–user space ABI. As ABI is a [[machine code]] interface, the Linux ABI is bound to the [[instruction set]]. Defining a useful ABI and keeping it stable is less the responsibility of the Linux kernel developers or of the developers of the GNU C Library, and more the task for [[Linux distribution]]s and [[independent software vendor]]s (ISVs) who wish to sell and provide support for their proprietary software as binaries only for such a single Linux ABI, as opposed to supporting multiple Linux ABIs.

	An ABI has to be defined for every instruction set, such as [[x86]], [[x86-64]], [[MIPS architecture\|MIPS]], [[ARMv7-A]] (32-Bit), [[ARMv8-A]] (64-Bit), etc. with the [[endianness]], if both are supported.		An ABI has to be defined for every instruction set, such as [[x86]], [[x86-64]], [[MIPS architecture\|MIPS]], [[ARMv7-A]] (32-Bit), [[ARMv8-A]] (64-Bit), etc. with the [[endianness]], if both are supported.

2600:1700:E4C0:9EA0:0:0:0:27: /* The C standard library */

2025-03-08T13:39:24Z

The C standard library

← Previous revision		Revision as of 13:39, 8 March 2025
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	* [[dietlibc]]		* [[dietlibc]]
	* [[Bionic (software)\|libbionic]] and [[Hybris (software)\|libhybris]]		* [[Bionic (software)\|libbionic]] and [[Hybris (software)\|libhybris]]

			Although the landscape is shifting, amongst these options, glibc remains the most popular implementation, to the point of many treating it as the default and the term equivalent to libc.

	==== Additions to POSIX ====		==== Additions to POSIX ====

GreenC bot: Rescued 3 archive links; reformat 3 links. Wayback Medic 2.5 per WP:USURPURL and JUDI batch #25ab

2025-03-03T06:25:57Z

Rescued 3 archive links; reformat 3 links. Wayback Medic 2.5 per WP:USURPURL and JUDI batch #25ab

← Previous revision		Revision as of 06:25, 3 March 2025
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	*[https://abi-laboratory.pro/?view=timeline&l=linux API/ABI changes review for Linux]		*[https://abi-laboratory.pro/?view=timeline&l=linux API/ABI changes review for Linux]
	* [http://man7.org/tlpi/ The Linux Programming Interface] book, [http://man7.org/tlpi/api_changes/ Linux and ''glibc'' API changes] since [[The Linux Programming Interface]] was released in 2010		* [http://man7.org/tlpi/ The Linux Programming Interface] book, [http://man7.org/tlpi/api_changes/ Linux and ''glibc'' API changes] since [[The Linux Programming Interface]] was released in 2010
	*[https://www.makelinux.net/kernel_map/ Interactive Linux kernel map] with main API functions and structures, [https://www.makelinux.net/kernel_map/LKM.pdf PDF] version		*{{usurped\|1=[https://archive.today/20121220032539/http://www.makelinux.net/kernel_map/ Interactive Linux kernel map]}} with main API functions and structures, {{usurped\|1=[https://web.archive.org/web/20180827040646/http://www.makelinux.net/kernel_map/LKM.pdf PDF]}} version
	* [http://www.makelinux.net/ldd3 Linux Device Drivers] by Jonathan Corbet, Greg Kroah-Hartman and Alessandro Rubini, 3rd edition		* {{usurped\|1=[https://archive.today/20130221193824/http://www.makelinux.net/ldd3 Linux Device Drivers]}} by Jonathan Corbet, Greg Kroah-Hartman and Alessandro Rubini, 3rd edition
	* [http://isis.poly.edu/kulesh/stuff/src/klist/ Linux Kernel Linked List Explained] {{Webarchive\|url=https://web.archive.org/web/20090925130610/http://isis.poly.edu/kulesh/stuff/src/klist/ \|date=2009-09-25 }}		* [http://isis.poly.edu/kulesh/stuff/src/klist/ Linux Kernel Linked List Explained] {{Webarchive\|url=https://web.archive.org/web/20090925130610/http://isis.poly.edu/kulesh/stuff/src/klist/ \|date=2009-09-25 }}

KMaster888: ce

2024-12-13T17:22:25Z

← Previous revision		Revision as of 17:22, 13 December 2024
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	== Linux ABI ==		== Linux ABI ==
	{{Expert needed\|~~Free~~ and open-source software\|ex2=~~Software~~\|ex3=~~Computing~~\|reason=This section mostly ignores the kernel-userspace ABI (that is very real and important thing) and jumps into userspace-to-userspace APIs\|date=February 2018}}		{{Expert needed\|free and open-source software\|ex2=software\|ex3=computing\|reason=This section mostly ignores the kernel-userspace ABI (that is very real and important thing) and jumps into userspace-to-userspace APIs\|date=February 2018}}
	[[File:Linux API and Linux ABI.svg\|thumb\|upright=1.5\|The Linux API and the Linux [[Application binary interface\|ABI]] ]]		[[File:Linux API and Linux ABI.svg\|thumb\|upright=1.5\|The Linux API and the Linux [[Application binary interface\|ABI]] ]]
	{{Main article\|x32 ABI\|Linux Standard Base}}		{{Main article\|x32 ABI\|Linux Standard Base}}

ShiinaKaze: Undid revision 1250592381 by ShiinaKaze (talk)

2024-10-11T09:46:37Z

Undid revision 1250592381 by ShiinaKaze (talk)

← Previous revision		Revision as of 09:46, 11 October 2024
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	Many kernel-internal APIs exist, allowing kernel subsystems to interface with one another. These are being kept fairly stable, but there is no guarantee for stability. A kernel-internal API can be changed when such a need is indicated by new research or insights; all necessary modifications and testing have to be done by the author.		Many kernel-internal APIs exist, allowing kernel subsystems to interface with one another. These are being kept fairly stable, but there is no guarantee for stability. A kernel-internal API can be changed when such a need is indicated by new research or insights; all necessary modifications and testing have to be done by the author.

	The Linux kernel is a monolithic kernel, hence device drivers are kernel components. To ease the burden of companies maintaining their (proprietary) device drivers outside of the main kernel tree, stable APIs for the device drivers have been repeatedly requested. The Linux kernel developers have repeatedly denied guaranteeing stable in-kernel APIs for device drivers. Guaranteeing such would have faltered the development of the Linux kernel in the past and would still in the future and, due to the nature of free and open-source software, are not necessary. Ergo, by choice, the Linux kernel has no ''stable'' in-kernel API.<ref>{{cite web ~~\|title=The Linux Kernel Driver Interface~~ \|url=https://~~www~~.kernel.org/~~doc~~/~~html~~/~~latest~~/process/stable-api-nonsense.~~html#stable-api-nonsense~~}}</ref>		The Linux kernel is a monolithic kernel, hence device drivers are kernel components. To ease the burden of companies maintaining their (proprietary) device drivers outside of the main kernel tree, stable APIs for the device drivers have been repeatedly requested. The Linux kernel developers have repeatedly denied guaranteeing stable in-kernel APIs for device drivers. Guaranteeing such would have faltered the development of the Linux kernel in the past and would still in the future and, due to the nature of free and open-source software, are not necessary. Ergo, by choice, the Linux kernel has no ''stable'' in-kernel API.<ref>{{cite web\|url=https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/stable-api-nonsense.rst \|title=The Linux Kernel Driver Interface}}</ref>

	== In-kernel ABIs ==		== In-kernel ABIs ==

ShiinaKaze at 09:38, 11 October 2024

2024-10-11T09:38:26Z

← Previous revision		Revision as of 09:38, 11 October 2024
Line 84:		Line 84:
	Many kernel-internal APIs exist, allowing kernel subsystems to interface with one another. These are being kept fairly stable, but there is no guarantee for stability. A kernel-internal API can be changed when such a need is indicated by new research or insights; all necessary modifications and testing have to be done by the author.		Many kernel-internal APIs exist, allowing kernel subsystems to interface with one another. These are being kept fairly stable, but there is no guarantee for stability. A kernel-internal API can be changed when such a need is indicated by new research or insights; all necessary modifications and testing have to be done by the author.

	The Linux kernel is a monolithic kernel, hence device drivers are kernel components. To ease the burden of companies maintaining their (proprietary) device drivers outside of the main kernel tree, stable APIs for the device drivers have been repeatedly requested. The Linux kernel developers have repeatedly denied guaranteeing stable in-kernel APIs for device drivers. Guaranteeing such would have faltered the development of the Linux kernel in the past and would still in the future and, due to the nature of free and open-source software, are not necessary. Ergo, by choice, the Linux kernel has no ''stable'' in-kernel API.<ref>{{cite web\|url=https://~~git~~.kernel.org/~~pub~~/~~scm~~/~~linux/kernel/git/torvalds/linux.git/tree/Documentation~~/process/stable-api-nonsense.~~rst \|title=The Linux Kernel Driver Interface~~}}</ref>		The Linux kernel is a monolithic kernel, hence device drivers are kernel components. To ease the burden of companies maintaining their (proprietary) device drivers outside of the main kernel tree, stable APIs for the device drivers have been repeatedly requested. The Linux kernel developers have repeatedly denied guaranteeing stable in-kernel APIs for device drivers. Guaranteeing such would have faltered the development of the Linux kernel in the past and would still in the future and, due to the nature of free and open-source software, are not necessary. Ergo, by choice, the Linux kernel has no ''stable'' in-kernel API.<ref>{{cite web \|title=The Linux Kernel Driver Interface \|url=https://www.kernel.org/doc/html/latest/process/stable-api-nonsense.html#stable-api-nonsense}}</ref>

	== In-kernel ABIs ==		== In-kernel ABIs ==

← Previous revision		Revision as of 20:59, 27 April 2025
Line 1:		Line 1:
	{{Short description\|~~An overview and comparison of the~~ Linux kernel ~~API~~ and ~~ABI.~~}}		{{Short description\|Linux kernel APIs and ABIs}}
	{{essay-like\|date=July 2014}}		{{essay-like\|date=July 2014}}

	[[File:Linux kernel interfaces.svg\|thumb\|upright=1.5\|Linux API, Linux ABI, and in-kernel APIs and ABIs]]		[[File:Linux kernel interfaces.svg\|thumb\|upright=1.5\|Linux API, Linux ABI, and in-kernel APIs and ABIs]]

	The [[Linux kernel]] provides multiple interfaces to [[User space and kernel space\|user-space and kernel-mode]] code ~~that~~ ~~are~~ ~~used~~ ~~for~~ ~~varying~~ ~~purposes~~ ~~and~~ ~~that~~ ~~have~~ ~~varying~~ ~~properties~~ ~~by design. There are two types of~~ [[application ~~programming~~ interface]] (~~API~~) in ~~the~~ ~~Linux~~ ~~kernel:~~ kernel–user space ~~and~~ kernel-internal.		The [[Linux kernel]] provides multiple interfaces to [[User space and kernel space\|user-space and kernel-mode]] code. The interfaces can be classified as either [[application programming interface]] (API) or [[application binary interface]] (ABI), and they can be classified as either kernel–user space or kernel-internal.

	== {{Anchor\|Linux API}}Linux API ==		== {{Anchor\|Linux API}}Linux API ==
Line 71:		Line 71:
	== Linux ABI ==		== Linux ABI ==
	{{Expert needed\|free and open-source software\|ex2=software\|ex3=computing\|reason=This section mostly ignores the kernel-userspace ABI (that is very real and important thing) and jumps into userspace-to-userspace APIs\|date=February 2018}}		{{Expert needed\|free and open-source software\|ex2=software\|ex3=computing\|reason=This section mostly ignores the kernel-userspace ABI (that is very real and important thing) and jumps into userspace-to-userspace APIs\|date=February 2018}}
	[[File:Linux API and Linux ABI.svg\|thumb\|upright=1.5\|The Linux API and ~~the Linux [[Application binary interface\|~~ABI]] ]]		[[File:Linux API and Linux ABI.svg\|thumb\|upright=1.5\|The Linux API and ABI ]]
	{{Main article\|x32 ABI\|Linux Standard Base}}		{{Main article\|x32 ABI\|Linux Standard Base}}

	The Linux ~~[[application binary interface]] (~~ABI) is a kernel–user space ABI. As ABI is a [[machine code]] interface, the Linux ABI is bound to the [[instruction set]]. Defining a useful ABI and keeping it stable is less the responsibility of the Linux kernel developers or of the developers of the GNU C Library, and more the task for [[Linux distribution]]s and [[independent software vendor]]s (ISVs) who wish to sell and provide support for their proprietary software as binaries only for such a single Linux ABI, as opposed to supporting multiple Linux ABIs.		The Linux ABI is a kernel–user space ABI. As ABI is a [[machine code]] interface, the Linux ABI is bound to the [[instruction set]]. Defining a useful ABI and keeping it stable is less the responsibility of the Linux kernel developers or of the developers of the GNU C Library, and more the task for [[Linux distribution]]s and [[independent software vendor]]s (ISVs) who wish to sell and provide support for their proprietary software as binaries only for such a single Linux ABI, as opposed to supporting multiple Linux ABIs.

	An ABI has to be defined for every instruction set, such as [[x86]], [[x86-64]], [[MIPS architecture\|MIPS]], [[ARMv7-A]] (32-Bit), [[ARMv8-A]] (64-Bit), etc. with the [[endianness]], if both are supported.		An ABI has to be defined for every instruction set, such as [[x86]], [[x86-64]], [[MIPS architecture\|MIPS]], [[ARMv7-A]] (32-Bit), [[ARMv8-A]] (64-Bit), etc. with the [[endianness]], if both are supported.

← Previous revision		Revision as of 20:53, 27 April 2025
Line 4:		Line 4:
	[[File:Linux kernel interfaces.svg\|thumb\|upright=1.5\|Linux API, Linux ABI, and in-kernel APIs and ABIs]]		[[File:Linux kernel interfaces.svg\|thumb\|upright=1.5\|Linux API, Linux ABI, and in-kernel APIs and ABIs]]

	The [[Linux kernel]] provides multiple interfaces to [[User space and kernel space\|user-space and kernel-mode]] code that are used for varying purposes and that have varying properties by design. There are two types of [[application programming interface]] (API) in the Linux kernel: kernel–user space and kernel internal.		The [[Linux kernel]] provides multiple interfaces to [[User space and kernel space\|user-space and kernel-mode]] code that are used for varying purposes and that have varying properties by design. There are two types of [[application programming interface]] (API) in the Linux kernel: kernel–user space and kernel-internal.

	== {{Anchor\|Linux API}}Linux API ==		== {{Anchor\|Linux API}}Linux API ==

@@ Line 103: / Line 103: @@
 == See also ==
 {{Portal|Linux}}
 == References ==