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Linus Torvalds 0771cee974 ftrace fixes for v6.19:
- Fix regression of pid filtering of function graph tracer
 
   When the function graph tracer allowed multiple instances of
   graph tracing using subops, the filtering by pid broke.
 
   The ftrace_ops->private that was used for pid filtering wasn't
   updated on creation.
 
   The wrong function entry callback was used when pid filtering was
   enabled when the function graph tracer started, which meant that
   the pid filtering wasn't happening.
 
 - Remove no longer needed ftrace_trace_task()
 
   With PID filtering working via ftrace_pids_enabled() and fgraph_pid_func(),
   the coarse-grained ftrace_trace_task() check in graph_entry() is obsolete.
 
   It was only a fallback for uninitialized op->private (now fixed), and its
   removal ensures consistent PID filtering with standard function tracing.
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Merge tag 'ftrace-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull ftrace updates from Steven Rostedt:

 - Fix regression of pid filtering of function graph tracer

   When the function graph tracer allowed multiple instances of graph
   tracing using subops, the filtering by pid broke.

   The ftrace_ops->private that was used for pid filtering wasn't
   updated on creation.

   The wrong function entry callback was used when pid filtering was
   enabled when the function graph tracer started, which meant that
   the pid filtering wasn't happening.

 - Remove no longer needed ftrace_trace_task()

   With PID filtering working via ftrace_pids_enabled() and
   fgraph_pid_func(), the coarse-grained ftrace_trace_task()
   check in graph_entry() is obsolete.

   It was only a fallback for uninitialized op->private (now fixed),
   and its removal ensures consistent PID filtering with standard
   function tracing.

* tag 'ftrace-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  fgraph: Remove coarse PID filtering from graph_entry()
  fgraph: Check ftrace_pids_enabled on registration for early filtering
  fgraph: Initialize ftrace_ops->private for function graph ops
2025-12-05 10:13:04 -08:00
arch IOMMU Updates for Linux v6.19 2025-12-04 18:05:06 -08:00
block VFIO updates for v6.19-rc1 2025-12-04 18:42:48 -08:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto Networking changes for 6.19. 2025-12-03 17:24:33 -08:00
Documentation tracing updates for v6.19: 2025-12-05 09:51:37 -08:00
drivers hardening updates for v6.19-rc1 2025-12-05 09:11:02 -08:00
fs pstore update for v6.19-rc1 2025-12-05 09:08:13 -08:00
include tracing updates for v6.19: 2025-12-05 09:51:37 -08:00
init drm-next for 6.19-rc1: 2025-12-04 08:53:30 -08:00
io_uring for-6.19/io_uring-20251201 2025-12-03 18:58:57 -08:00
ipc vfs-6.19-rc1.fd_prepare.fs 2025-12-01 17:32:07 -08:00
kernel ftrace fixes for v6.19: 2025-12-05 10:13:04 -08:00
lib sound updates for 6.19-rc1 2025-12-04 10:08:40 -08:00
LICENSES LICENSES: Replace the obsolete address of the FSF in the GFDL-1.2 2025-07-24 11:15:39 +02:00
mm VFIO updates for v6.19-rc1 2025-12-04 18:42:48 -08:00
net for-6.19/io_uring-20251201 2025-12-03 18:58:57 -08:00
rust pwm: Changes for v6.19-rc1 2025-12-04 11:04:38 -08:00
samples VFIO updates for v6.19-rc1 2025-12-04 18:42:48 -08:00
scripts Detect unused tracepoints for v6.19: 2025-12-05 09:37:41 -08:00
security Capabilities patch for v6.19 2025-12-04 20:10:28 -08:00
sound firewire updates for v6.19 2025-12-04 12:26:36 -08:00
tools rtla updaets for v6.19: 2025-12-05 09:34:01 -08:00
usr initramfs: add gen_init_cpio to hostprogs unconditionally 2025-11-26 21:55:40 +01:00
virt A large overhaul of the restartable sequences and CID management: 2025-12-02 08:48:53 -08:00
.clang-format IOMMU Updates for Linux v6.19 2025-12-04 18:05:06 -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 scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.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 IOMMU Updates for Linux v6.19 2025-12-04 18:05:06 -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 MAINTAINERS: mark ISDN subsystem as orphan 2025-10-27 17:49:45 -07:00
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 rtla updaets for v6.19: 2025-12-05 09:34:01 -08:00
Makefile Detect unused tracepoints for v6.19: 2025-12-05 09:37:41 -08:00
README README: restructure with role-based documentation and guidelines 2025-11-29 08:40:33 -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


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



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