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Linus Torvalds de02909ae8 configfs work
A couple of fixes (UAF in configfs_lookup() and really old races
 introduced when lseek() on configfs directories stopped locking those
 directories; impact up to and including UAF).
 
 Fixes aside, the main result is that configfs is finally switched
 to tree-in-dcache machinery.  It's *not* making use of recursive removal
 helpers yet, and it still does the bloody awful "build subtree in full
 sight of userland, with possibility of failure halfway through and need
 to unroll" that forces the locking model from hell; dealing with that
 is a separate patch series, once this one is out of the way.  However,
 it is using DCACHE_PERSISTENT properly now.  And apparmorfs is the sole
 remaining user of __simple_{unlink,rmdir}() at that point.
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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 68DcAQCrG0zPl8BwHlKVVlylAzgjK2lY120bHX36a4+qLmFE4AD9HTeSgqoZ8vAv
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Merge tag 'pull-configfs-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull configfs updates from Al Viro:
 "A couple of fixes (UAF in configfs_lookup() and really old races
  introduced when lseek() on configfs directories stopped locking those
  directories; impact up to and including UAF).

  Fixes aside, the main result is that configfs is finally switched to
  tree-in-dcache machinery. It's *not* making use of recursive removal
  helpers yet, and it still does the bloody awful "build subtree in full
  sight of userland, with possibility of failure halfway through and
  need to unroll" that forces the locking model from hell; dealing with
  that is a separate patch series, once this one is out of the way.
  However, it is using DCACHE_PERSISTENT properly now. And apparmorfs is
  the sole remaining user of __simple_{unlink,rmdir}() at that point"

* tag 'pull-configfs-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  create_default_group(): pass parent's dentry instead of config_group
  configfs_attach_group(): drop the unused parent_item argument
  configs_attach_item(): drop unused parent_item argument
  configfs_create(): lift parent timestamp updates into callers
  kill configfs_drop_dentry()
  configfs: mark pinned dentries persistent
  configfs: dentry refcount needs to be pinned only once
  switch configfs_detach_{group,item}() to passing dentry
  configfs_remove_dir(), detach_attrs(): switch to passing dentry
  populate_attrs(): move cleanup to the sole caller
  populate_group(): move cleanup on failure to the sole caller
  configfs_detach_rollback(): pass configfs_dirent instead of dentry
  configfs_do_depend_item(): pass configfs_dirent instead of dentry
  configfs_depend_prep(): pass configfs_dirent instead of dentry
  configfs_detach_prep(): pass configfs_dirent instead of dentry
  configfs_mkdir(): use take_dentry_name_snapshot()
  configfs: fix lockless traversals of ->s_children
  configfs_lookup(): don't leave ->s_dentry dangling on failure
2026-06-15 04:28:20 +05:30
arch vfs-7.2-rc1.misc 2026-06-15 03:59:45 +05:30
block block-7.1-20260529 2026-05-29 10:41:07 -07:00
certs Clang build fixes for 7.1 2026-04-24 09:29:51 -07:00
crypto crypto/krb5, rxrpc: Fix lack of pre-decrypt/pre-verify length checks 2026-05-20 16:36:45 -07:00
Documentation dentry memory safety stuff 2026-06-15 04:15:31 +05:30
drivers vfs-7.2-rc1.bh 2026-06-15 03:36:08 +05:30
fs configfs work 2026-06-15 04:28:20 +05:30
include dentry memory safety stuff 2026-06-15 04:15:31 +05:30
init vfs-7.2-rc1.misc 2026-06-15 03:59:45 +05:30
io_uring io_uring-7.1-20260611 2026-06-12 10:49:59 -07:00
ipc kernel-7.2-rc1.misc 2026-06-15 03:05:50 +05:30
kernel vfs-7.2-rc1.procfs 2026-06-15 04:07:58 +05:30
lib vfs-7.2-rc1.misc 2026-06-15 03:59:45 +05:30
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 vfs-7.2-rc1.misc 2026-06-15 03:59:45 +05:30
net vfs-7.2-rc1.xattr 2026-06-15 03:54:54 +05:30
rust rust: i2c: fix I2cAdapter refcount double increment 2026-06-08 09:47:50 +02:00
samples soc: drivers for 7.1 2026-04-16 20:34:34 -07:00
scripts Rust fixes for v7.1 (2nd) 2026-06-06 09:44:42 -07:00
security vfs-7.2-rc1.inode 2026-06-15 02:44:23 +05:30
sound ASoC: Fixes for v7.1 2026-06-11 21:29:47 +02:00
tools vfs-7.2-rc1.misc 2026-06-15 03:59:45 +05:30
usr kbuild: uapi: also test UAPI headers against C++ compilers 2026-03-25 13:24:42 +01:00
virt vfs-7.2-rc1.misc 2026-06-15 03:59:45 +05:30
.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
.editorconfig editorconfig: add rst extension 2026-01-26 19:07:09 -08:00
.get_maintainer.ignore .get_maintainer.ignore: add Askar 2026-04-15 02:15:02 -07:00
.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: update Baoquan He's email address 2026-06-03 16:25:50 -07:00
.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 Delete some obsolete networking code 2026-04-24 09:41:58 -07:00
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 vfs-7.2-rc1.exportfs 2026-06-15 02:38:54 +05:30
Makefile Linux 7.1 2026-06-14 15:58:38 +01:00
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