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Rafael J. Wysocki becbdde56a Merge branches 'pm-powercap' and 'pm-cpuidle'
Merge additional power capping and cpuidle updates for 7.0-rc1:

 - Fix the handling of package-scope MSRs in the intel_rapl power
   capping driver when called from the PMU subsystem and make it add all
   package CPUs to the PMU cpumask to allow tools to read RAPL events
   from any CPU in the package (Kuppuswamy Sathyanarayanan)

 - Rework the invalid version check in the intel_rapl_tpmi power capping
   driver to account for the fact that on partitioned systems, multiple
   TPMI instances may exist per package, but RAPL registers are only
   valid on one instance (Kuppuswamy Satharayananyan)

 - Describe the new intel_idle.table command line option in the
   admin-guide intel_idle documentation (Artem Bityutskiy)

 - Fix a crash in the ladder cpuidle governor on systems with only one
   (polling) idle state available by making the cpuidle core bypass the
   governor in those cases and adjust the other existing governors to
   that change (Aboorva Devarajan, Christian Loehle)

* pm-powercap:
  powercap: intel_rapl_tpmi: Remove FW_BUG from invalid version check
  powercap: intel_rapl: Expose all package CPUs in PMU cpumask
  powercap: intel_rapl: Remove incorrect CPU check in PMU context

* pm-cpuidle:
  cpuidle: menu: Remove single state handling
  cpuidle: teo: Remove single state handling
  cpuidle: haltpoll: Remove single state handling
  cpuidle: Skip governor when only one idle state is available
  Documentation: PM: Document intel_idle.table command line option
2026-02-18 19:48:30 +01:00
arch struct filename series 2026-02-09 16:58:28 -08:00
block for-7.0/block-stable-pages-20260206 2026-02-09 18:14:52 -08:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto crypto: authencesn - reject too-short AAD (assoclen<8) to match ESP/ESN spec 2026-01-20 14:38:48 +08:00
Documentation Documentation: PM: Document intel_idle.table command line option 2026-02-11 21:08:23 +01:00
drivers Merge branches 'pm-powercap' and 'pm-cpuidle' 2026-02-18 19:48:30 +01:00
fs for-7.0/block-stable-pages-20260206 2026-02-09 18:14:52 -08:00
include powercap: intel_rapl: Remove incorrect CPU check in PMU context 2026-02-11 21:03:39 +01:00
init vfs-7.0-rc1.misc 2026-02-09 15:13:05 -08:00
io_uring for-7.0/block-20260206 2026-02-09 17:57:21 -08:00
ipc mqueue: switch to CLASS(filename) 2026-01-16 12:52:04 -05:00
kernel Power management updates for 6.20-rc1/7.0-rc1 2026-02-09 19:00:42 -08:00
lib for-7.0/block-stable-pages-20260206 2026-02-09 18:14:52 -08:00
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 struct filename series 2026-02-09 16:58:28 -08:00
net audit/stable-7.0 PR 20260203 2026-02-09 10:13:03 -08:00
rust Power management updates for 6.20-rc1/7.0-rc1 2026-02-09 19:00:42 -08:00
samples samples/ftrace: Adjust LoongArch register restore order in direct calls 2025-12-31 15:19:25 +08:00
scripts RCU changes for v7.0 2026-02-09 09:46:26 -08:00
security selinux/stable-7.0 PR 20260203 2026-02-09 10:38:05 -08:00
sound ALSA: hda/realtek: Enable headset mic for Acer Nitro 5 2026-02-05 09:05:10 +01:00
tools Power management updates for 6.20-rc1/7.0-rc1 2026-02-09 19:00:42 -08:00
usr initramfs: add gen_init_cpio to hostprogs unconditionally 2025-11-26 21:55:40 +01:00
virt KVM: Don't clobber irqfd routing type when deassigning irqfd 2026-01-14 13:17:14 -08:00
.clang-format s390/pci: Fix cyclic dead-lock in zpci_zdev_put() and zpci_scan_devices() 2025-12-14 11:03:58 +01:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: remove Alyssa Rosenzweig 2025-09-18 21:17:31 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore rust: kbuild: add proc macro library support 2025-11-24 17:15:36 +01:00
.mailmap 5 hotfixes. 2 are cc:stable, 2 are for MM. 2026-02-04 16:04:00 -08:00
.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 nfc: MAINTAINERS: Orphan the NFC and look for new maintainers 2026-01-20 16:05:38 -08:00
Kbuild sched: Make migrate_{en,dis}able() inline 2025-09-25 09:57:16 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS Power management updates for 6.20-rc1/7.0-rc1 2026-02-09 19:00:42 -08:00
Makefile Linux 6.19 2026-02-08 13:03:27 -08:00
README README: restructure with role-based documentation and guidelines 2025-11-29 08:40:33 -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


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



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