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Linus Torvalds c7decec2f2 perf tools changes for v7.0:
- Introduce 'perf sched stats' tool with record/report/diff workflows
   using schedstat counters.
 
 - Add a faster libdw based addr2line implementation and allow selecting
   it or its alternatives via 'perf config addr2line.style='.
 
 - Data-type profiling fixes and improvements including the ability
   to select fields using 'perf report''s -F/-fields, e.g.:
 
     'perf report --fields overhead,type'
 
 - Add 'perf test' regression tests for Data-type profiling with
   C and Rust workloads.
 
 - Fix srcline printing with inlines in callchains, make sure this has
   coverage in 'perf test'.
 
 - Fix printing of leaf IP in LBR callchains.
 
 - Fix display of metrics without sufficient permission in 'perf stat'.
 
 - Print all machines in 'perf kvm report -vvv', not just the host.
 
 - Switch from SHA-1 to BLAKE2s for build ID generation, remove SHA-1
   code.
 
 - Fix 'perf report's histogram entry collapsing with '-F' option.
 
 - Use system's cacheline size instead of a hardcoded value in 'perf
   report'.
 
 - Allow filtering conversion by time range in 'perf data'.
 
 - Cover conversion to CTF using 'perf data' in 'perf test'.
 
 - Address newer glibc const-correctness (-Werror=discarded-qualifiers)
   issues.
 
 - Fixes and improvements for ARM's CoreSight support, simplify ARM SPE
   event config in 'perf mem', update docs for 'perf c2c' including the
   ARM events it can be used with.
 
 - Build support for generating metrics from arch specific python script,
   add extra AMD, Intel, ARM64 metrics using it.
 
 - Add AMD Zen 6 events and metrics.
 
 - Add JSON file with OpenHW Risc-V CVA6 hardware counters.
 
 - Add 'perf kvm' stats live testing.
 
 - Add more 'perf stat' tests to 'perf test'.
 
 - Fix segfault in `perf lock contention -b/--use-bpf`
 
 - Fix various 'perf test' cases for s390.
 
 - Build system cleanups, bump minimum shellcheck version to 0.7.2
 
 - Support building the capstone based annotation routines as a plugin.
 
 - Allow passing extra Clang flags via EXTRA_BPF_FLAGS.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-tools-for-v7.0-1-2026-02-21' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools

Pull perf tools updates from Arnaldo Carvalho de Melo:

 - Introduce 'perf sched stats' tool with record/report/diff workflows
   using schedstat counters

 - Add a faster libdw based addr2line implementation and allow selecting
   it or its alternatives via 'perf config addr2line.style='

 - Data-type profiling fixes and improvements including the ability to
   select fields using 'perf report''s -F/-fields, e.g.:

     'perf report --fields overhead,type'

 - Add 'perf test' regression tests for Data-type profiling with C and
   Rust workloads

 - Fix srcline printing with inlines in callchains, make sure this has
   coverage in 'perf test'

 - Fix printing of leaf IP in LBR callchains

 - Fix display of metrics without sufficient permission in 'perf stat'

 - Print all machines in 'perf kvm report -vvv', not just the host

 - Switch from SHA-1 to BLAKE2s for build ID generation, remove SHA-1
   code

 - Fix 'perf report's histogram entry collapsing with '-F' option

 - Use system's cacheline size instead of a hardcoded value in 'perf
   report'

 - Allow filtering conversion by time range in 'perf data'

 - Cover conversion to CTF using 'perf data' in 'perf test'

 - Address newer glibc const-correctness (-Werror=discarded-qualifiers)
   issues

 - Fixes and improvements for ARM's CoreSight support, simplify ARM SPE
   event config in 'perf mem', update docs for 'perf c2c' including the
   ARM events it can be used with

 - Build support for generating metrics from arch specific python
   script, add extra AMD, Intel, ARM64 metrics using it

 - Add AMD Zen 6 events and metrics

 - Add JSON file with OpenHW Risc-V CVA6 hardware counters

 - Add 'perf kvm' stats live testing

 - Add more 'perf stat' tests to 'perf test'

 - Fix segfault in `perf lock contention -b/--use-bpf`

 - Fix various 'perf test' cases for s390

 - Build system cleanups, bump minimum shellcheck version to 0.7.2

 - Support building the capstone based annotation routines as a plugin

 - Allow passing extra Clang flags via EXTRA_BPF_FLAGS

* tag 'perf-tools-for-v7.0-1-2026-02-21' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (255 commits)
  perf test script: Add python script testing support
  perf test script: Add perl script testing support
  perf script: Allow the generated script to be a path
  perf test: perf data --to-ctf testing
  perf test: Test pipe mode with data conversion --to-json
  perf json: Pipe mode --to-ctf support
  perf json: Pipe mode --to-json support
  perf check: Add libbabeltrace to the listed features
  perf build: Allow passing extra Clang flags via EXTRA_BPF_FLAGS
  perf test data_type_profiling.sh: Skip just the Rust tests if code_with_type workload is missing
  tools build: Fix feature test for rust compiler
  perf libunwind: Fix calls to thread__e_machine()
  perf stat: Add no-affinity flag
  perf evlist: Reduce affinity use and move into iterator, fix no affinity
  perf evlist: Missing TPEBS close in evlist__close()
  perf evlist: Special map propagation for tool events that read on 1 CPU
  perf stat-shadow: In prepare_metric fix guard on reading NULL perf_stat_evsel
  Revert "perf tool_pmu: More accurately set the cpus for tool events"
  tools build: Emit dependencies file for test-rust.bin
  tools build: Make test-rust.bin be removed by the 'clean' target
  ...
2026-02-21 10:51:08 -08:00
arch kmalloc_obj prep for v7.0-rc1 2026-02-20 12:51:07 -08:00
block block-7.0-20260216 2026-02-17 08:48:45 -08:00
certs mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -08:00
crypto mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -08:00
Documentation Documentation: Coccinelle: document debug log handling 2026-02-21 17:22:45 +01:00
drivers NTB updates include debugfs improvements, correctness fixes, 2026-02-21 10:20:32 -08:00
fs io_uring-20260221 2026-02-21 10:05:49 -08:00
include NTB updates include debugfs improvements, correctness fixes, 2026-02-21 10:20:32 -08:00
init mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -08:00
io_uring io_uring: add IORING_OP_URING_CMD128 to opcode checks 2026-02-19 07:25:39 -07:00
ipc mm.git review status for linus..mm-stable 2026-02-18 20:50:32 -08:00
kernel Tracing fixes for 7.0: 2026-02-20 15:05:26 -08:00
lib mm.git review status for linus..mm-nonmm-stable 2026-02-18 21:40:16 -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 memblock: numa_memblks: fix detection of NUMA node for CXL windows 2026-02-21 09:58:22 -08:00
net Including fixes from Netfilter. 2026-02-19 10:39:08 -08:00
rust USB / Thunderbolt changes for 7.0-rc1 2026-02-17 09:36:43 -08:00
samples USB / Thunderbolt changes for 7.0-rc1 2026-02-17 09:36:43 -08:00
scripts scripts: coccicheck: warn on unset debug file 2026-02-21 17:22:30 +01:00
security + Features 2026-02-20 14:06:06 -08:00
sound sound fixes for 7.0-rc1 2026-02-20 15:47:44 -08:00
tools perf tools changes for v7.0: 2026-02-21 10:51:08 -08:00
usr kbuild: uapi: drop dependency on CC_CAN_LINK 2026-01-16 15:02:11 -07:00
virt Merge tag 'kvm-x86-pmu-6.20' of https://github.com/kvm-x86/linux into HEAD 2026-02-11 12:45:40 -05:00
.clang-format Devicetree updates for v7.0: 2026-02-11 18:27:08 -08:00
.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: add rst extension 2026-01-26 19:07:09 -08:00
.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 Landlock update for v7.0-rc1 2026-02-11 15:57:08 -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 Networking changes for 7.0 2026-02-11 19:31:52 -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 EFI fixes for v7.0 #1 2026-02-20 12:04:40 -08:00
Makefile First round of Kbuild fixes for 7.0 2026-02-18 14:59:55 -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