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Linus Torvalds bb29b957ea Kbuild / Kconfig updates for 7.4
Kbuild:
 
 - Suppress compiler flags in debug info for external module builds
 
 - Use '-fmacro-prefix-map' in more places in the build
 
 - Merge initial set of changes from Lorenzo's speed up series, along
   with some fixes found through testing
 
   - Avoid allocating .modinfo in vmlinux
 
   - Speed up kallsyms by indexing symbols by token and outputting binary
     data to disk directly then including in assembly via .incbin
 
   - Don't sort $(NM) output when unnecessary
 
   - Only emit relocations on the final vmlinx link
 
   - Reimplement mksysmap in C
 
   - Move many cc-option and ld-option calls into the Kconfig stage to
     cache their results
 
   - Use pigz for gzip compression when available
 
 - Move gen_init_cpio and gen_initramfs.sh from usr/ to scripts/
 
 - Add a TOML configuration to scripts/container and update documentation
   accordingly
 
 - Add a generic, opt-in mechanism for checking that headers can compile
   standalone
 
 - Update machine function splitting argument for LLVM 24 rename in
   AutoFDO build
 
 - Miscellaneous minor clean ups, fixes, and hardening, mostly
   found/fixed via LLMs
 
 Kconfig:
 
 - Turn recursive ranges into an error
 
 - Fix savedefconfig for defaults that were adjusted for being out of
   range and revert a previously applied workaround
 
 - Improvements and hardening around integer and hexadecimal values
 
 - Emit a warning when selecting or implying a choice symbol, which has no
   effect
 
 - Emit a warning when KCONFIG_PROBABILITY is malformed
 
 - Introduce def_string / def_int / def_hex to mirror the existing
   def_bool / def_tristate to succinctly set a value and type at the same
   time.
 
 - Add cc-option-str and ld-option-str macros to act like Kbuild's
   cc-option and ld-option, returning the string when the option is
   supported, allowing many checks to be moved into Kconfig
 
 - Minor usability improvements to Kconfig tests
 
 Signed-off-by: Nathan Chancellor <nathan@kernel.org>
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Merge tag 'kbuild-7.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux

Pull Kbuild / Kconfig updates from Nathan Chancellor:
 "Kbuild:

   - Suppress compiler flags in debug info for external module builds

   - Use '-fmacro-prefix-map' in more places in the build

   - Merge initial set of changes from Lorenzo's speed up series, along
     with some fixes found through testing:

     - Avoid allocating .modinfo in vmlinux

     - Speed up kallsyms by indexing symbols by token and outputting
       binary data to disk directly then including in assembly via
       .incbin

     - Don't sort $(NM) output when unnecessary

     - Only emit relocations on the final vmlinx link

     - Reimplement mksysmap in C

     - Move many cc-option and ld-option calls into the Kconfig stage to
       cache their results

     - Use pigz for gzip compression when available

   - Move gen_init_cpio and gen_initramfs.sh from usr/ to scripts/

   - Add a TOML configuration to scripts/container and update
     documentation accordingly

   - Add a generic, opt-in mechanism for checking that headers can
     compile standalone

   - Update machine function splitting argument for LLVM 24 rename in
     AutoFDO build

   - Miscellaneous minor clean ups, fixes, and hardening, mostly
     found/fixed via LLMs

  Kconfig:

   - Turn recursive ranges into an error

   - Fix savedefconfig for defaults that were adjusted for being out of
     range and revert a previously applied workaround

   - Improvements and hardening around integer and hexadecimal values

   - Emit a warning when selecting or implying a choice symbol, which
     has no effect

   - Emit a warning when KCONFIG_PROBABILITY is malformed

   - Introduce def_string / def_int / def_hex to mirror the existing
     def_bool / def_tristate to succinctly set a value and type at the
     same time.

   - Add cc-option-str and ld-option-str macros to act like Kbuild's
     cc-option and ld-option, returning the string when the option is
     supported, allowing many checks to be moved into Kconfig

   - Minor usability improvements to Kconfig tests"

* tag 'kbuild-7.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (59 commits)
  kbuild: AutoFDO: Update split machine function argument for upstream rename
  kbuild: Mark the initcall ordering recipe as recursive
  kbuild: Mark the gzip recipes as recursive
  localmodconfig: Explicitly report boolean configs during integrity check
  scripts/make_fit: Ignore schema checks when decomposing DTBs
  clang-tools: Import os for broken pipe handling
  kconfig: use the value argument in sym_get_near_range_bound()
  kconfig: fix infinite loop in conf_choice() when no choice value is visible
  kconfig: cleanup stale comment about 'keys' array
  kconfig: Improve ergonomics around disabling warnings with cc-option
  scripts/Kconfig.toolchain: Drop compiler symbols from dependencies
  checkkconfigsymbols.py: Parse Git status output line by line
  gen_init_cpio: stop parsing on lines with a missing argument list
  .gitignore: drop Module.markers
  .gitignore: ignore pacman package signatures
  kbuild: add header check facility as a manually run static analyzer
  Documentation: dev-tools: refer to user ID rather than id
  Documentation: dev-tools: update container.rst with config file
  scripts: add TOML config to container tool
  kconfig: tests: {old,save}defconfig: Forward dynamic keyword arguments
  ...
2026-10-21 10:45:44 -10:00
arch Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
block vfs-7.4-rc1.iomap 2026-10-19 18:33:02 -10:00
certs treewide: fix indentation and whitespace in Kconfig files 2026-05-28 21:24:42 -07:00
crypto lib/crypto: sparc/aes-xts: Add optimization using the AES opcodes 2026-10-04 21:40:47 +02:00
Documentation Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
drivers Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
fs Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
include Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
init Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
io_uring vfs-7.4-rc1.file 2026-10-19 17:35:50 -10:00
ipc vfs-7.4-rc1.idmap 2026-10-19 17:57:49 -10:00
kernel Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
lib bitmap updates for v7.4 2026-10-21 09:49:47 -10:00
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 \n 2026-10-20 16:30:13 -10:00
net Merge __{get,put}_user() removal branch 2026-10-21 07:19:30 -10:00
rust Rust changes for v7.4 2026-10-21 10:20:36 -10:00
samples configfs: Updates for v7.4 2026-10-20 16:25:43 -10:00
scripts Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
security lsm/stable-7.4 PR 20261016 2026-10-20 20:04:07 -10:00
sound ASoC: amd: yc: disable MSI on resume 2026-10-13 14:32:22 +01:00
tools Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
usr Merge branch 'kbuild-next-speedups' into kbuild-next 2026-10-17 15:20:23 -07:00
virt vfs-7.4-rc1.idmap 2026-10-19 17:57:49 -10:00
.clang-format drm/bridge: rename drm_for_each_bridge_in_chain_scoped() to drm_for_each_bridge_in_chain() 2026-07-14 17:55:51 +02:00
.clippy.toml rust: bump Clippy's MSRV and clean incompatible_msrv allows 2026-04-07 09:51:39 +02:00
.cocciconfig
.editorconfig editorconfig: add rst extension 2026-01-26 19:07:09 -08:00
.get_maintainer.ignore .get_maintainer.ignore: add myself 2026-09-07 10:01:33 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore .gitignore: drop Module.markers 2026-10-04 18:18:08 +02:00
.mailmap Changes since last update: 2026-10-20 16:50:37 -10:00
.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
AGENTS.md docs: add AGENTS.md as a symlink to README 2026-10-14 11:45:46 -06:00
COPYING
CREDITS vfs-7.4-rc1.bfs 2026-10-19 16:55:31 -10:00
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 Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
Makefile Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
README README: remove out of place emdashes 2026-07-15 10:51:29 -06:00

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