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Waiman Long d56281fefb selftests/cgroup: Fix minor defects in test_cpuset
With commit 98149f5425 ("selftests/cgroup: Add test for cpuset affinity
on controller disable"), sashiko [1] reported 3 different issues with
the new test_cpuset_affinity_on_controller_disable() test.

 1) `cpu_set_equal` iterates over mask bytes instead of bits, ignoring
    CPUs >= 8.
 2) Thread synchronization logic allows the main thread to read
    uninitialized stack memory, causing test flakiness.
 3) Test fails instead of skipping gracefully on uniprocessor systems
    or when CPU 1 is unavailable.

Fix the reported issues by:
 1) Iterates over the bit size of the mask.
 2) Test the new ready flag for each thread to end the wait
    on the conditional variable and eliminate the now unneeded
    AFFINITY_THREAD_A_READY and AFFINITY_THREADS_READY test phases.
 3) Return KSFT_SKIP on "cpuset.cpus" setting failure.

[1] https://sashiko.dev/#/patchset/20260712235510.373125-1-longman%40redhat.com

Fixes: 98149f5425 ("selftests/cgroup: Add test for cpuset affinity on controller disable")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-07-17 12:12:44 -10:00
arch - Prevent NULL dereference on theoretical missing IO bitmap 2026-06-23 17:16:31 -07:00
block - small cleanups in dm-vdo, dm-raid, dm-cache, dm-zoned-metadata 2026-06-16 13:20:54 +05:30
certs treewide: fix indentation and whitespace in Kconfig files 2026-05-28 21:24:42 -07:00
crypto mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -07:00
Documentation Docs/admin-guide/cgroup-v2: fix delay_nsec unit in io.latency doc 2026-07-17 07:05:59 -10:00
drivers Miscellaneous irqchip driver fixes: 2026-06-23 16:02:03 -07:00
fs Changes for 7.2-rc1 2026-06-24 10:05:53 -07:00
include cgroup: Use data_race() for task->flags in task_css_set_check() 2026-06-25 11:12:19 -10:00
init mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -07:00
io_uring for-7.2/io_uring-epoll-20260616 2026-06-18 08:09:57 -07:00
ipc kernel-7.2-rc1.misc 2026-06-15 03:05:50 +05:30
kernel cgroup/cpuset: Handle the special case of non-moving tasks in cpuset_can_attach() 2026-07-16 09:37:50 -10:00
lib Misc fixes: 2026-06-23 16:05:54 -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 mm.git review status for linus..mm-stable 2026-06-23 12:03:44 -07:00
net NFS Client Updates for Linux 7.2 2026-06-23 18:36:41 -07:00
rust Char/Misc/IIO/FPGA/GPIB/etc driver updates for 7.2-rc1 2026-06-22 12:20:21 -07:00
samples Char/Misc/IIO/FPGA/GPIB/etc driver updates for 7.2-rc1 2026-06-22 12:20:21 -07:00
scripts platform-drivers-x86 for v7.2-1 2026-06-23 08:31:33 -07:00
security Landlock update for v7.2-rc1 2026-06-19 12:20:25 -07:00
sound dmaengine updates for v7.2 2026-06-23 15:51:14 -07:00
tools selftests/cgroup: Fix minor defects in test_cpuset 2026-07-17 12:12:44 -10:00
usr kbuild: uapi: also test UAPI headers against C++ compilers 2026-03-25 13:24:42 +01:00
virt Arm: 2026-06-19 08:56:49 -07:00
.clang-format clang-format: fix formatting of guard() and scoped_guard() statements 2026-05-28 21:24:41 -07:00
.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 SPDX patches for 7.2-rc1 2026-06-22 12:06:22 -07:00
.mailmap mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -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 COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -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 dmaengine updates for v7.2 2026-06-23 15:51:14 -07:00
Makefile SPDX patches for 7.2-rc1 2026-06-22 12:06:22 -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