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Linus Torvalds 148f95f75c slab updates for 7.0
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Merge tag 'slab-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

Pull slab updates from Vlastimil Babka:

 - The percpu sheaves caching layer was introduced as opt-in in 6.18 and
   now we enable it for all caches and remove the previous cpu (partial)
   slab caching mechanism.

   Besides the lower locking overhead and much more likely fastpath when
   freeing, this removes the rather complicated code related to the cpu
   slab lockless fastpaths (using this_cpu_try_cmpxchg128/64) and all
   its complications for PREEMPT_RT or kmalloc_nolock().

   The lockless slab freelist+counters update operation using
   try_cmpxchg128/64 remains and is crucial for freeing remote NUMA
   objects, and to allow flushing objects from sheaves to slabs mostly
   without the node list_lock (Vlastimil Babka)

 - Eliminate slabobj_ext metadata overhead when possible. Instead of
   using kmalloc() to allocate the array for memcg and/or allocation
   profiling tag pointers, use leftover space in a slab or per-object
   padding due to alignment (Harry Yoo)

 - Various followup improvements to the above (Hao Li)

* tag 'slab-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: (39 commits)
  slub: let need_slab_obj_exts() return false if SLAB_NO_OBJ_EXT is set
  mm/slab: only allow SLAB_OBJ_EXT_IN_OBJ for unmergeable caches
  mm/slab: place slabobj_ext metadata in unused space within s->size
  mm/slab: move [__]ksize and slab_ksize() to mm/slub.c
  mm/slab: save memory by allocating slabobj_ext array from leftover
  mm/memcontrol,alloc_tag: handle slabobj_ext access under KASAN poison
  mm/slab: use stride to access slabobj_ext
  mm/slab: abstract slabobj_ext access via new slab_obj_ext() helper
  ext4: specify the free pointer offset for ext4_inode_cache
  mm/slab: allow specifying free pointer offset when using constructor
  mm/slab: use unsigned long for orig_size to ensure proper metadata align
  slub: clarify object field layout comments
  mm/slab: avoid allocating slabobj_ext array from its own slab
  slub: avoid list_lock contention from __refill_objects_any()
  mm/slub: cleanup and repurpose some stat items
  mm/slub: remove DEACTIVATE_TO_* stat items
  slab: remove frozen slab checks from __slab_free()
  slab: update overview comments
  slab: refill sheaves from all nodes
  slab: remove unused PREEMPT_RT specific macros
  ...
2026-02-11 14:12:50 -08:00
arch Kbuild/Kconfig updates for 7.0 2026-02-11 13:40:35 -08:00
block The kthread code provides an infrastructure which manages the preferred 2026-02-09 19:57:30 -08:00
certs modsign: Enable ML-DSA module signing 2026-02-02 16:57:39 +00:00
crypto Locking updates for v6.20: 2026-02-10 12:28:44 -08:00
Documentation Kbuild/Kconfig updates for 7.0 2026-02-11 13:40:35 -08:00
drivers Kbuild/Kconfig updates for 7.0 2026-02-11 13:40:35 -08:00
fs slab updates for 7.0 2026-02-11 14:12:50 -08:00
include slab updates for 7.0 2026-02-11 14:12:50 -08:00
init Kbuild/Kconfig updates for 7.0 2026-02-11 13:40:35 -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 Kbuild/Kconfig updates for 7.0 2026-02-11 13:40:35 -08:00
lib workqueue: Changes for v6.20 2026-02-11 13:13:32 -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 slab updates for 7.0 2026-02-11 14:12:50 -08:00
net Locking updates for v6.20: 2026-02-10 12:28:44 -08:00
rust drm for 7.0-rc1 2026-02-11 12:55:44 -08:00
samples samples: rust: remove imports available via prelude 2026-01-26 18:15:20 +01:00
scripts Kbuild/Kconfig updates for 7.0 2026-02-11 13:40:35 -08:00
security powerpc updates for 7.0 2026-02-10 21:46:12 -08:00
sound sound updates for 7.0-rc1 2026-02-11 11:43:00 -08:00
tools Kbuild/Kconfig updates for 7.0 2026-02-11 13:40:35 -08:00
usr kbuild: uapi: drop dependency on CC_CAN_LINK 2026-01-16 15:02:11 -07:00
virt Performance events changes for v7.0: 2026-02-10 12:00:46 -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 drm for 7.0-rc1 2026-02-11 12:55:44 -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
CREDITS - Remove two drivers for obsolete hardware: i82443bxgx_edac and r82600_edac 2026-02-10 18:14:36 -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 Kbuild/Kconfig updates for 7.0 2026-02-11 13:40:35 -08:00
Makefile Kbuild/Kconfig updates for 7.0 2026-02-11 13:40:35 -08:00
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