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Linus Torvalds 3e48a11675 f2fs-for-7.0-rc1
In this development cycle, we focused on several key performance optimizations:
 1) introducing large folio support to enhance read speeds for immutable files,
 2) reducing checkpoint=enable latency by flushing only committed dirty pages,
 and 3) implementing tracepoints to diagnose and resolve lock priority inversion.
 Additionally, we introduced the packed_ssa feature to optimize the SSA footprint
 when utilizing large block sizes.
 
 Enhancement:
  - support large folio for immutable non-compressed case
  - support non-4KB block size without packed_ssa feature
  - optimize f2fs_enable_checkpoint() to avoid long delay
  - optimize f2fs_overwrite_io() for f2fs_iomap_begin
  - optimize NAT block loading during checkpoint write
  - add write latency stats for NAT and SIT blocks in f2fs_write_checkpoint
  - pin files do not require sbi->writepages lock for ordering
  - avoid f2fs_map_blocks() for consecutive holes in readpages
  - flush plug periodically during GC to maximize readahead effect
  - add tracepoints to catch lock overheads
  - add several sysfs entries to tune internal lock priorities
 
 Bug fix:
  - fix lock priority inversion issue
  - fix incomplete block usage in compact SSA summaries
  - fix to show simulate_lock_timeout correctly
  - fix to avoid mapping wrong physical block for swapfile
  - fix IS_CHECKPOINTED flag inconsistency issue caused by concurrent atomic
    commit and checkpoint writes
  - fix to avoid UAF in f2fs_write_end_io()
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Merge tag 'f2fs-for-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "In this development cycle, we focused on several key performance
  optimizations:

   - introducing large folio support to enhance read speeds for
     immutable files

   - reducing checkpoint=enable latency by flushing only committed dirty
     pages

   - implementing tracepoints to diagnose and resolve lock priority
     inversion.

  Additionally, we introduced the packed_ssa feature to optimize the SSA
  footprint when utilizing large block sizes.

  Detail summary:

  Enhancements:
   - support large folio for immutable non-compressed case
   - support non-4KB block size without packed_ssa feature
   - optimize f2fs_enable_checkpoint() to avoid long delay
   - optimize f2fs_overwrite_io() for f2fs_iomap_begin
   - optimize NAT block loading during checkpoint write
   - add write latency stats for NAT and SIT blocks in
     f2fs_write_checkpoint
   - pin files do not require sbi->writepages lock for ordering
   - avoid f2fs_map_blocks() for consecutive holes in readpages
   - flush plug periodically during GC to maximize readahead effect
   - add tracepoints to catch lock overheads
   - add several sysfs entries to tune internal lock priorities

  Fixes:
   - fix lock priority inversion issue
   - fix incomplete block usage in compact SSA summaries
   - fix to show simulate_lock_timeout correctly
   - fix to avoid mapping wrong physical block for swapfile
   - fix IS_CHECKPOINTED flag inconsistency issue caused by
     concurrent atomic commit and checkpoint writes
   - fix to avoid UAF in f2fs_write_end_io()"

* tag 'f2fs-for-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (61 commits)
  f2fs: sysfs: introduce critical_task_priority
  f2fs: introduce trace_f2fs_priority_update
  f2fs: fix lock priority inversion issue
  f2fs: optimize f2fs_overwrite_io() for f2fs_iomap_begin
  f2fs: fix incomplete block usage in compact SSA summaries
  f2fs: decrease maximum flush retry count in f2fs_enable_checkpoint()
  f2fs: optimize NAT block loading during checkpoint write
  f2fs: change size parameter of __has_cursum_space() to unsigned int
  f2fs: add write latency stats for NAT and SIT blocks in f2fs_write_checkpoint
  f2fs: pin files do not require sbi->writepages lock for ordering
  f2fs: fix to show simulate_lock_timeout correctly
  f2fs: introduce FAULT_SKIP_WRITE
  f2fs: check skipped write in f2fs_enable_checkpoint()
  Revert "f2fs: add timeout in f2fs_enable_checkpoint()"
  f2fs: fix to unlock folio in f2fs_read_data_large_folio()
  f2fs: fix error path handling in f2fs_read_data_large_folio()
  f2fs: use folio_end_read
  f2fs: fix to avoid mapping wrong physical block for swapfile
  f2fs: avoid f2fs_map_blocks() for consecutive holes in readpages
  f2fs: advance index and offset after zeroing in large folio read
  ...
2026-02-14 09:48:10 -08:00
arch Loongarch: 2026-02-13 11:31:15 -08:00
block mm.git review status for linus..mm-stable 2026-02-12 11:32:37 -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 f2fs-for-7.0-rc1 2026-02-14 09:48:10 -08:00
drivers platform-drivers-x86 for v7.0-1 2026-02-13 15:39:15 -08:00
fs f2fs-for-7.0-rc1 2026-02-14 09:48:10 -08:00
include f2fs-for-7.0-rc1 2026-02-14 09:48:10 -08:00
init mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -08:00
io_uring for-7.0/io_uring-zcrx-large-buffers-20260206 2026-02-12 15:07:50 -08:00
ipc mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -08:00
kernel tracing updates for 7.0: 2026-02-13 19:25:16 -08:00
lib Bootconfig for v7.0 2026-02-13 19:33:39 -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 Three MM hotfixes, all three are cc:stable. 2026-02-13 12:13:27 -08:00
net virtio,vhost,vdpa: features, fixes 2026-02-13 12:02:18 -08:00
rust configfs changes for v7.0 2026-02-12 14:01:38 -08:00
samples configfs changes for v7.0 2026-02-12 14:01:38 -08:00
scripts virtio,vhost,vdpa: features, fixes 2026-02-13 12:02:18 -08:00
security mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -08:00
sound mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -08:00
tools Bootconfig for v7.0 2026-02-13 19:33:39 -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 tracing updates for 7.0: 2026-02-13 19:25:16 -08:00
Makefile Devicetree updates for v7.0: 2026-02-11 18:27:08 -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