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Linus Torvalds 55ee4b931a Real-time Verifier updates for v7.3
- Switch LTL and DOT parsers to Lark in code generation tool
 
   The rvgen code generation tool originally parsed DOT files and LTL
   specifications using custom string parsing and Ply, which is no longer
   maintained. The DOT parser was fragile and prone to failure on minor
   format variations. Both LTL and DOT parsers have been rewritten to use
   the Lark parsing library.
 
 - Simplify Hybrid Automata clock variables
 
   The clock variables in hybrid automata monitors now use a single
   representation of the elapsed time since the clock was reset, rather
   than converting between invariant and guard representations.
   This allows simpler code generation for the newly refactored parser.
 
 - Generate cleanup hook for per-obj monitor
 
   The code generation scripts now adds a cleanup function to per-obj
   monitors for the user to wire to the appropriate event (e.g.
   sched_process_exit for tasks).
 
 - Reduce read_lock scope during per-task cleanup
 
   Take the tasklist_lock only when necessary, that is when iterating
   over for_each_process_thread().
 
 - Simplify task monitor slot management
 
   Only rely on the slot array for per-task slot management to avoid
   inconsistency with the unused counter.
 
 - Improve rvgen code robustness and templates
 
   Use pathlib in rvgen and improve kernel path discovery. Also improve
   consistency across templates when generating code (e.g. author
   placeholder and monitor struct name).
 
 - Update rtapp sleep monitor
 
   Simplify the sleep monitor by excluding kernel threads and
   updating the nanosleep check to focus only on CLOCK_REALTIME. Also
   switch to use the sched_exit tracepoint to run in the context of the
   offending (wakee) task.
 
 - Add wakeup monitor
 
   Add the new rtapp/wakeup monitor to detect when lower-priority tasks
   wake up higher-priority ones, complementing the existing sleep monitor
   by running in the waker context and capturing its stack trace.
 
 - Fix tools/rv exit status on failure
 
   Ensure the rv tool returns a failure exit code when a monitor fails to
   start because it was already running.
 
 - Add automated selftests for tools/rv and rvgen
 
   Introduced automated bash selftests to validate rv monitor listing and
   execution under different configurations. Added tests for the rvgen code
   generator, validating generated files against expected output (golden).
   Tests are reachable via make check.
 
 - Add KUnit test coverage for verification monitors
 
   Added comprehensive KUnit tests to validate the functionality of
   deterministic, hybrid, and LTL monitors by emulating event sequences
   and timing in a mock environment without affecting the running kernel
   while expecting mock reactions to fire. Ensure real RV monitors cannot
   run during KUnit tests to avoid state corruption.
 
 - Mock current in rv monitors
 
   Mock the call to current in rv monitors when the KUnit tests are built
   to allow them to run the test on dummy tasks. No overhead is expected
   when KUnit tests aren't running.
 
 - Introduce rvgen kunit subcommand
 
   Added a new 'kunit' subcommand to rvgen to automatically patch an already
   generated monitor with KUnit integration templates by parsing its event
   handlers and creating the required mock structures and initializations.
 
 - Refine kernel verification selftests
 
   Added new selftests for the deadline and stall monitors and rearranged
   the existing wwnr_printk test to resolve flakiness.
   Additionally, fixed an issue in the selftests framework where negative
   assertion failures were not correctly propagated due to shell rules.
 
 - Fix 32-bit build of nomiss KUnit test
 
   A previous commit introduced a division between an u64 and a constant
   value and that doesn't build on 32-bit systems. Use div_u64() instead.
 
 - Document changes in sleep monitor
 
   The sleep monitor introduced some changes in the past like allowing
   epoll_wait() as a valid sleep and a task going to runnable before
   scheduling as a valid wakeup. Document both.
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Merge tag 'trace-rv-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull Real-time Verifier updates from Steven Rostedt:

 - Switch LTL and DOT parsers to Lark in code generation tool

   The rvgen code generation tool originally parsed DOT files and LTL
   specifications using custom string parsing and Ply, which is no
   longer maintained. The DOT parser was fragile and prone to failure on
   minor format variations. Both LTL and DOT parsers have been rewritten
   to use the Lark parsing library.

 - Simplify Hybrid Automata clock variables

   The clock variables in hybrid automata monitors now use a single
   representation of the elapsed time since the clock was reset, rather
   than converting between invariant and guard representations. This
   allows simpler code generation for the newly refactored parser.

 - Generate cleanup hook for per-obj monitor

   The code generation scripts now adds a cleanup function to per-obj
   monitors for the user to wire to the appropriate event (e.g.
   sched_process_exit for tasks).

 - Reduce read_lock scope during per-task cleanup

   Take the tasklist_lock only when necessary, that is when iterating
   over for_each_process_thread().

 - Simplify task monitor slot management

   Only rely on the slot array for per-task slot management to avoid
   inconsistency with the unused counter.

 - Improve rvgen code robustness and templates

   Use pathlib in rvgen and improve kernel path discovery. Also improve
   consistency across templates when generating code (e.g. author
   placeholder and monitor struct name).

 - Update rtapp sleep monitor

   Simplify the sleep monitor by excluding kernel threads and updating
   the nanosleep check to focus only on CLOCK_REALTIME. Also switch to
   use the sched_exit tracepoint to run in the context of the offending
   (wakee) task.

 - Add wakeup monitor

   Add the new rtapp/wakeup monitor to detect when lower-priority tasks
   wake up higher-priority ones, complementing the existing sleep
   monitor by running in the waker context and capturing its stack
   trace.

 - Fix tools/rv exit status on failure

   Ensure the rv tool returns a failure exit code when a monitor fails
   to start because it was already running.

 - Add automated selftests for tools/rv and rvgen

   Introduced automated bash selftests to validate rv monitor listing
   and execution under different configurations. Added tests for the
   rvgen code generator, validating generated files against expected
   output (golden). Tests are reachable via make check.

 - Add KUnit test coverage for verification monitors

   Added comprehensive KUnit tests to validate the functionality of
   deterministic, hybrid, and LTL monitors by emulating event sequences
   and timing in a mock environment without affecting the running kernel
   while expecting mock reactions to fire. Ensure real RV monitors
   cannot run during KUnit tests to avoid state corruption.

 - Mock current in rv monitors

   Mock the call to current in rv monitors when the KUnit tests are
   built to allow them to run the test on dummy tasks. No overhead is
   expected when KUnit tests aren't running.

 - Introduce rvgen kunit subcommand

   Added a new 'kunit' subcommand to rvgen to automatically patch an
   already generated monitor with KUnit integration templates by parsing
   its event handlers and creating the required mock structures and
   initializations.

 - Refine kernel verification selftests

   Added new selftests for the deadline and stall monitors and
   rearranged the existing wwnr_printk test to resolve flakiness.
   Additionally, fixed an issue in the selftests framework where
   negative assertion failures were not correctly propagated due to
   shell rules.

 - Fix 32-bit build of nomiss KUnit test

   A previous commit introduced a division between an u64 and a constant
   value and that doesn't build on 32-bit systems. Use div_u64()
   instead.

 - Document changes in sleep monitor

   The sleep monitor introduced some changes in the past like allowing
   epoll_wait() as a valid sleep and a task going to runnable before
   scheduling as a valid wakeup. Document both.

* tag 'trace-rv-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (40 commits)
  Documentation/rv: Explain epoll and aborted sleeps
  rv: Fix 32-bit build of nomiss KUnit test
  selftests/verification: Add selftests for deadline and stall monitors
  selftests/verification: Rearrange the wwnr_printk test
  selftests/verification: Fix wrong errexit assumption
  rv: Add KUnit tests for some LTL monitors
  rv: Add KUnit mock for current
  rv: Add KUnit tests for some DA/HA monitors
  rv: Export task monitor slot and react symbols
  verification/rvgen: Add selftests for rvgen kunit
  verification/rvgen: Add the rvgen kunit subcommand
  verification/rvgen: Add selftests
  verification/rvgen: Add golden and spec folders for tests
  tools/rv: Add selftests
  verification/rvgen: Improve consistency in template files
  verification/rvgen: Use pathlib instead of os.path
  verification/rvgen: Improve rv_dir discovery in RVGenerator
  tools/rv: Fix exit status when monitor execution fails
  rv: Use generic rv_this for the rv_monitor variable in LTL
  rv/rtapp: Add wakeup monitor
  ...
2026-08-19 13:29:22 -07:00
arch IOMMU updates for Linux v7.3: 2026-08-19 12:38:26 -07:00
block fscrypt updates for 7.3 2026-08-17 19:04:16 -07:00
certs treewide: fix indentation and whitespace in Kconfig files 2026-05-28 21:24:42 -07:00
crypto Crypto library updates for 7.3 2026-08-17 19:16:42 -07:00
Documentation Real-time Verifier updates for v7.3 2026-08-19 13:29:22 -07:00
drivers fwctl 7.3 pull request 2026-08-19 12:51:36 -07:00
fs Driver core changes for 7.3-rc1 2026-08-19 10:42:18 -07:00
include Real-time Verifier updates for v7.3 2026-08-19 13:29:22 -07:00
init VDSO updates: 2026-08-18 16:56:25 -07:00
io_uring io_uring/rsrc: reject overflowing regvec bvec byte counts 2026-08-12 19:53:35 -06:00
ipc vfs-7.3-rc1.lookup 2026-08-17 12:03:34 -07:00
kernel Real-time Verifier updates for v7.3 2026-08-19 13:29:22 -07:00
lib Driver core changes for 7.3-rc1 2026-08-19 10:42:18 -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 memblock: updates for 7.3-rc1 2026-08-18 10:03:54 -07:00
net Crypto library updates for 7.3 2026-08-17 19:16:42 -07:00
rust fwctl 7.3 pull request 2026-08-19 12:51:36 -07:00
samples Linux 7.2-rc7 2026-08-10 01:20:05 +02:00
scripts Devicetree updates for v7.3: 2026-08-19 10:32:34 -07:00
security selinux/stable-7.2 PR 20260805 2026-08-05 13:40:11 -07:00
sound sound updates for 7.3-rc1 2026-08-19 10:04:59 -07:00
tools Real-time Verifier updates for v7.3 2026-08-19 13:29:22 -07:00
usr usr: Correct a spelling by changing a letter 2026-08-05 14:51:58 +02:00
virt KVM/arm64 fixes for 7.2, take #2 2026-07-15 12:13:30 +02:00
.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
.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 There is a known WiFi/mt76 regression, waiting for a complete fix that 2026-08-13 08:37:26 -07:00
.pylintrc docs: Move the python libraries to tools/lib/python 2025-11-18 09:22:40 -07:00
.rustfmt.toml
COPYING
CREDITS [GIT PULL for v7.3] media updates 2026-08-19 10:09:22 -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 fwctl 7.3 pull request 2026-08-19 12:51:36 -07:00
Makefile Kbuild/Kconfig updates for 7.3 2026-08-18 09:26:31 -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