Linux kernel source tree
Go to file
Linus Torvalds f21f7b5162 Update to the VDSO subsystem:
- Make the handling of compat functions consistent and more robust
 
      - Rework the underlying data store so that it is dynamically
        allocated, which allows the conversion of the last holdout SPARC64
        to the generic VDSO implementation
 
      - Rework the SPARC64 VDSO to utilize the generic implementation
 
      - Mop up the left overs of the non-generic VDSO support in the core
        code.
 
      - Expand the VDSO selftest and make them more robust
 
      - Allow time namespaces to be enabled independently of the generic
        VDSO support, which was not possible before due to SPARC64 not
        using it.
 
      - Various cleanups and improvements in the related code.
 -----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCgAuFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmnb0v8QHHRnbHhAa2Vy
 bmVsLm9yZwAKCRCmGPVMDXSYocfqD/9ywgnvwRH6B612mY4PI3qCbLHs6n9f78aH
 YwyXmmfBZ5vt1ZtptHD+BAxiIMm9GC+/exdj5zhcOWucnBVhorcloE6evxhkJAMn
 RhTQFKkEmcA/UV2Yfct9r+33kgZRyu4IIul4J7hgn2o5T1BqwZbOil0W/O5adr5P
 MDLxjT1OLV80ZZWI9qbWcR/aR7W7sHcdwfVPPqjhombRY7f391Mo3dZeM5C2y55x
 8TXCEqVpN1RJzFinWEgQN7QpP4OmF0rRuXSrDQpkH6pk/+RSqNlT/QGG7MJtmCQR
 E6CeBjNRUn318KiroaGyTKlM9xsL3gNoiCY24ZTwzZxx3g5gSAR3KTCTJhQU0hpu
 Svxj+ksqEAyW7fAOIsbce6W8fUPKC2KM+juXgPKcqZ5hjE2fALD+eEYMlq00jSiu
 sj71007cM9tZKOXPdWs3Fv7AY2Yj7iiRiRz9gv1wqS1z7ybxiaFjxjLYYakej0tr
 rmwBDEGhNow7msZZttr01BRZk9hDUWfIiJtL+0BrgRLNzst2A7WoagtZ2s0Z7Psl
 RjtWgYNBDJ878xK0J+Djqb9TyLraGWZShIIna9uYCAJX9i954xfKJ//NOnUkZhcl
 jslDLHhdttyJ+TmgIsc1ntUGvYvHqH5ywQpyDfWepMKyIYdaJLHOr2K6bwFnGHdw
 uocXvLrkXw==
 =8ixX
 -----END PGP SIGNATURE-----

Merge tag 'timers-vdso-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull vdso updates from Thomas Gleixner:

 - Make the handling of compat functions consistent and more robust

 - Rework the underlying data store so that it is dynamically allocated,
   which allows the conversion of the last holdout SPARC64 to the
   generic VDSO implementation

 - Rework the SPARC64 VDSO to utilize the generic implementation

 - Mop up the left overs of the non-generic VDSO support in the core
   code

 - Expand the VDSO selftest and make them more robust

 - Allow time namespaces to be enabled independently of the generic VDSO
   support, which was not possible before due to SPARC64 not using it

 - Various cleanups and improvements in the related code

* tag 'timers-vdso-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  timens: Use task_lock guard in timens_get*()
  timens: Use mutex guard in proc_timens_set_offset()
  timens: Simplify some calls to put_time_ns()
  timens: Add a __free() wrapper for put_time_ns()
  timens: Remove dependency on the vDSO
  vdso/timens: Move functions to new file
  selftests: vDSO: vdso_test_correctness: Add a test for time()
  selftests: vDSO: vdso_test_correctness: Use facilities from parse_vdso.c
  selftests: vDSO: vdso_test_correctness: Handle different tv_usec types
  selftests: vDSO: vdso_test_correctness: Drop SYS_getcpu fallbacks
  selftests: vDSO: vdso_test_gettimeofday: Remove nolibc checks
  Revert "selftests: vDSO: parse_vdso: Use UAPI headers instead of libc headers"
  random: vDSO: Remove ifdeffery
  random: vDSO: Trim vDSO includes
  vdso/datapage: Trim down unnecessary includes
  vdso/datapage: Remove inclusion of gettimeofday.h
  vdso/helpers: Explicitly include vdso/processor.h
  vdso/gettimeofday: Add explicit includes
  random: vDSO: Add explicit includes
  MIPS: vdso: Explicitly include asm/vdso/vdso.h
  ...
2026-04-14 10:53:44 -07:00
arch Update to the VDSO subsystem: 2026-04-14 10:53:44 -07:00
block for-7.1/block-20260411 2026-04-13 15:51:31 -07:00
certs Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
crypto CRC updates for 7.1 2026-04-13 17:36:04 -07:00
Documentation Updates for the timer/timekeeping core: 2026-04-14 10:27:07 -07:00
drivers Update to the VDSO subsystem: 2026-04-14 10:53:44 -07:00
fs Driver core changes for 7.1-rc1 2026-04-13 19:03:11 -07:00
include Update to the VDSO subsystem: 2026-04-14 10:53:44 -07:00
init Update to the VDSO subsystem: 2026-04-14 10:53:44 -07:00
io_uring for-7.1/io_uring-20260411 2026-04-13 16:22:30 -07:00
ipc Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
kernel Update to the VDSO subsystem: 2026-04-14 10:53:44 -07:00
lib Update to the VDSO subsystem: 2026-04-14 10:53:44 -07:00
LICENSES LICENSES: Add modern form of the LGPL-2.1 tags to the usage guide section 2025-10-22 07:58:19 +02:00
mm for-7.1/block-20260411 2026-04-13 15:51:31 -07:00
net Crypto library updates for 7.1 2026-04-13 17:31:39 -07:00
rust Power management updates for 7.1-rc1 2026-04-13 19:47:52 -07:00
samples Driver core changes for 7.1-rc1 2026-04-13 19:03:11 -07:00
scripts Updates for the timer/timekeeping core: 2026-04-14 10:27:07 -07:00
security Crypto library updates for 7.1 2026-04-13 17:31:39 -07:00
sound ASoC: Fixes for v7.0 2026-04-09 07:00:53 +02:00
tools Update to the VDSO subsystem: 2026-04-14 10:53:44 -07:00
usr kbuild: uapi: also test UAPI headers against C++ compilers 2026-03-25 13:24:42 +01:00
virt vfs-7.1-rc1.bh.metadata 2026-04-13 12:46:42 -07:00
.clang-format Devicetree updates for v7.0: 2026-02-11 18:27:08 -08:00
.clippy.toml rust: bump Clippy's MSRV and clean incompatible_msrv allows 2026-04-07 09:51:39 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig editorconfig: add rst extension 2026-01-26 19:07:09 -08:00
.get_maintainer.ignore .get_maintainer.ignore: add myself 2026-04-02 16:48:25 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: rust: provide an option to inline C helpers into Rust 2026-03-30 02:03:52 +02:00
.mailmap MAINTAINERS, mailmap: Change Ulf Hansson's email 2026-04-07 14:17:48 +02:00
.pylintrc docs: Move the python libraries to tools/lib/python 2025-11-18 09:22:40 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: remove Thomas Falcon from IBM ibmvnic 2026-03-05 07:35:45 -08:00
Kbuild checksyscalls: move instance functionality into generic code 2026-04-05 09:21:32 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS Update to the VDSO subsystem: 2026-04-14 10:53:44 -07:00
Makefile Kbuild/Kconfig updates for 7.1 2026-04-14 09:18:40 -07:00
README docs: add AI Coding Assistants documentation 2026-01-06 14:55:06 -07:00

Linux kernel
============

The Linux kernel is the core of any Linux operating system. It manages hardware,
system resources, and provides the fundamental services for all other software.

Quick Start
-----------

* Report a bug: See Documentation/admin-guide/reporting-issues.rst
* Get the latest kernel: https://kernel.org
* Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst
* Join the community: https://lore.kernel.org/

Essential Documentation
-----------------------

All users should be familiar with:

* Building requirements: Documentation/process/changes.rst
* Code of Conduct: Documentation/process/code-of-conduct.rst
* License: See COPYING

Documentation can be built with make htmldocs or viewed online at:
https://www.kernel.org/doc/html/latest/


Who Are You?
============

Find your role below:

* New Kernel Developer - Getting started with kernel development
* Academic Researcher - Studying kernel internals and architecture
* Security Expert - Hardening and vulnerability analysis
* Backport/Maintenance Engineer - Maintaining stable kernels
* System Administrator - Configuring and troubleshooting
* Maintainer - Leading subsystems and reviewing patches
* Hardware Vendor - Writing drivers for new hardware
* Distribution Maintainer - Packaging kernels for distros
* AI Coding Assistant - LLMs and AI-powered development tools


For Specific Users
==================

New Kernel Developer
--------------------

Welcome! Start your kernel development journey here:

* Getting Started: Documentation/process/development-process.rst
* Your First Patch: Documentation/process/submitting-patches.rst
* Coding Style: Documentation/process/coding-style.rst
* Build System: Documentation/kbuild/index.rst
* Development Tools: Documentation/dev-tools/index.rst
* Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst
* Core APIs: Documentation/core-api/index.rst

Academic Researcher
-------------------

Explore the kernel's architecture and internals:

* Researcher Guidelines: Documentation/process/researcher-guidelines.rst
* Memory Management: Documentation/mm/index.rst
* Scheduler: Documentation/scheduler/index.rst
* Networking Stack: Documentation/networking/index.rst
* Filesystems: Documentation/filesystems/index.rst
* RCU (Read-Copy Update): Documentation/RCU/index.rst
* Locking Primitives: Documentation/locking/index.rst
* Power Management: Documentation/power/index.rst

Security Expert
---------------

Security documentation and hardening guides:

* Security Documentation: Documentation/security/index.rst
* LSM Development: Documentation/security/lsm-development.rst
* Self Protection: Documentation/security/self-protection.rst
* Reporting Vulnerabilities: Documentation/process/security-bugs.rst
* CVE Procedures: Documentation/process/cve.rst
* Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst
* Security Features: Documentation/userspace-api/seccomp_filter.rst

Backport/Maintenance Engineer
-----------------------------

Maintain and stabilize kernel versions:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* Backporting Guide: Documentation/process/backporting.rst
* Applying Patches: Documentation/process/applying-patches.rst
* Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git for Maintainers: Documentation/maintainer/configure-git.rst

System Administrator
--------------------

Configure, tune, and troubleshoot Linux systems:

* Admin Guide: Documentation/admin-guide/index.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst
* Tracing/Debugging: Documentation/trace/index.rst
* Performance Security: Documentation/admin-guide/perf-security.rst
* Hardware Monitoring: Documentation/hwmon/index.rst

Maintainer
----------

Lead kernel subsystems and manage contributions:

* Maintainer Handbook: Documentation/maintainer/index.rst
* Pull Requests: Documentation/maintainer/pull-requests.rst
* Managing Patches: Documentation/maintainer/modifying-patches.rst
* Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst
* Development Process: Documentation/process/maintainer-handbooks.rst
* Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git Configuration: Documentation/maintainer/configure-git.rst

Hardware Vendor
---------------

Write drivers and support new hardware:

* Driver API Guide: Documentation/driver-api/index.rst
* Driver Model: Documentation/driver-api/driver-model/driver.rst
* Device Drivers: Documentation/driver-api/infrastructure.rst
* Bus Types: Documentation/driver-api/driver-model/bus.rst
* Device Tree Bindings: Documentation/devicetree/bindings/
* Power Management: Documentation/driver-api/pm/index.rst
* DMA API: Documentation/core-api/dma-api.rst

Distribution Maintainer
-----------------------

Package and distribute the kernel:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* ABI Documentation: Documentation/ABI/README
* Kernel Configuration: Documentation/kbuild/kconfig.rst
* Module Signing: Documentation/admin-guide/module-signing.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst

AI Coding Assistant
-------------------

CRITICAL: If you are an LLM or AI-powered coding assistant, you MUST read and
follow the AI coding assistants documentation before contributing to the Linux
kernel:

* Documentation/process/coding-assistants.rst

This documentation contains essential requirements about licensing, attribution,
and the Developer Certificate of Origin that all AI tools must comply with.


Communication and Support
=========================

* Mailing Lists: https://lore.kernel.org/
* IRC: #kernelnewbies on irc.oftc.net
* Bugzilla: https://bugzilla.kernel.org/
* MAINTAINERS file: Lists subsystem maintainers and mailing lists
* Email Clients: Documentation/process/email-clients.rst