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Linus Torvalds e812928be2 cxl changes for v7.0
- A set of commits that introduces cxl_memdev_attach and pave way for
   soft reserved handling, type2 accelerator enabling, and LSA 2.0
   enabling. All these series require the endpoint driver to settle
   before continuing the memdev driver probe.
 
 dax/hmem, e820, resource: Defer Soft Reserved insertion until hmem is ready
 cxl/mem: Introduce cxl_memdev_attach for CXL-dependent operation
 cxl/mem: Drop @host argument to devm_cxl_add_memdev()
 cxl/mem: Convert devm_cxl_add_memdev() to scope-based-cleanup
 cxl/port: Arrange for always synchronous endpoint attach
 cxl/mem: Arrange for always-synchronous memdev attach
 cxl/mem: Fix devm_cxl_memdev_edac_release() confusion
 
 - A set to address CXL port error protocol handling and reporting. The
   large patch series was split into 3 parts. Part 1 and 2 are included
   here with part 3 coming later. Part 1 consists of a series of code
   refactoring to PCI AER sub-system that addresses CXL and also CXL
   RAS code to prepare for port error handling. Part 2 refactors the
   CXL code to move management of component registers to cxl_port
   objects to allow all CXL AER errors to be handled through the
   cxl_port hierarchy.
 
 Part 2:
 cxl/port: Move endpoint component register management to cxl_port
 cxl/port: Map Port RAS registers
 cxl/port: Move dport RAS setup to dport add time
 cxl/port: Move dport probe operations to a driver event
 cxl/port: Move decoder setup before dport creation
 cxl/port: Cleanup dport removal with a devres group
 cxl/port: Reduce number of @dport variables in cxl_port_add_dport()
 cxl/port: Cleanup handling of the nr_dports 0 -> 1 transition
 
 Part 1:
 cxl: Update RAS handler interfaces to also support CXL Ports
 cxl/mem: Clarify @host for devm_cxl_add_nvdimm()
 PCI/AER: Update struct aer_err_info with kernel-doc formatting
 PCI/AER: Report CXL or PCIe bus type in AER trace logging
 PCI/AER: Use guard() in cxl_rch_handle_error_iter()
 PCI/AER: Move CXL RCH error handling to aer_cxl_rch.c
 PCI/AER: Update is_internal_error() to be non-static is_aer_internal_error()
 PCI/AER: Export pci_aer_unmask_internal_errors()
 cxl/pci: Move CXL driver's RCH error handling into core/ras_rch.c
 PCI/AER: Replace PCIEAER_CXL symbol with CXL_RAS
 cxl/pci: Remove CXL VH handling in CONFIG_PCIEAER_CXL conditional blocks from core/pci.c
 PCI: Replace cxl_error_is_native() with pcie_aer_is_native()
 cxl/pci: Remove unnecessary CXL RCH handling helper functions
 cxl/pci: Remove unnecessary CXL Endpoint handling helper functions
 PCI: Introduce pcie_is_cxl()
 PCI: Update CXL DVSEC definitions
 PCI: Move CXL DVSEC definitions into uapi/linux/pci_regs.h
 
 - A set of patches to provide AMD Zen5 platform address translation for
   CXL using ACPI PRMT. Set includes a conventions document to explain
   why this is needed and how it's implemented.
 
 cxl: Disable HPA/SPA translation handlers for Normalized Addressing
 cxl/region: Factor out code into cxl_region_setup_poison()
 cxl/atl: Lock decoders that need address translation
 cxl: Enable AMD Zen5 address translation using ACPI PRMT
 cxl/acpi: Prepare use of EFI runtime services
 cxl: Introduce callback for HPA address ranges translation
 cxl/region: Use region data to get the root decoder
 cxl/region: Add @hpa_range argument to function cxl_calc_interleave_pos()
 cxl/region: Separate region parameter setup and region construction
 cxl: Simplify cxl_root_ops allocation and handling
 cxl/region: Store HPA range in struct cxl_region
 cxl/region: Store root decoder in struct cxl_region
 cxl/region: Rename misleading variable name @hpa to @hpa_range
 Documentation/driver-api/cxl: ACPI PRM Address Translation Support and AMD Zen5 enablement
 cxl, doc: Moving conventions in separate files
 cxl, doc: Remove isonum.txt inclusion
 
 - A set of misc CXL patches of fixes, cleanups, and updates. Including
   CXL address translation for unaligned MOD3 regions.
 
 cxl: Fix premature commit_end increment on decoder commit failure
 cxl/region: Use do_div() for 64-bit modulo operation
 cxl/region: Translate HPA to DPA and memdev in unaligned regions
 cxl/region: Translate DPA->HPA in unaligned MOD3 regions
 cxl/core: Fix cxl_dport debugfs EINJ entries
 cxl/acpi: Remove cxl_acpi_set_cache_size()
 cxl/hdm: Fix newline character in dev_err() messages
 cxl/pci: Remove outdated FIXME comment and BUILD_BUG_ON
 Documentation/driver-api/cxl: device hotplug section
 Documentation/driver-api/cxl: BIOS/EFI expectation update
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Merge tag 'cxl-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull CXL updates from Dave Jiang:

 - Introduce cxl_memdev_attach and pave way for soft reserved handling,
   type2 accelerator enabling, and LSA 2.0 enabling. All these series
   require the endpoint driver to settle before continuing the memdev
   driver probe.

 - Address CXL port error protocol handling and reporting.

   The large patch series was split into three parts. The first two
   parts are included here with the final part coming later.

   The first part consists of a series of code refactoring to PCI AER
   sub-system that addresses CXL and also CXL RAS code to prepare for
   port error handling.

   The second part refactors the CXL code to move management of
   component registers to cxl_port objects to allow all CXL AER errors
   to be handled through the cxl_port hierarchy.

 - Provide AMD Zen5 platform address translation for CXL using ACPI
   PRMT. This includes a conventions document to explain why this is
   needed and how it's implemented.

 - Misc CXL patches of fixes, cleanups, and updates. Including CXL
   address translation for unaligned MOD3 regions.

[ TLA service: CXL is "Compute Express Link" ]

* tag 'cxl-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (59 commits)
  cxl: Disable HPA/SPA translation handlers for Normalized Addressing
  cxl/region: Factor out code into cxl_region_setup_poison()
  cxl/atl: Lock decoders that need address translation
  cxl: Enable AMD Zen5 address translation using ACPI PRMT
  cxl/acpi: Prepare use of EFI runtime services
  cxl: Introduce callback for HPA address ranges translation
  cxl/region: Use region data to get the root decoder
  cxl/region: Add @hpa_range argument to function cxl_calc_interleave_pos()
  cxl/region: Separate region parameter setup and region construction
  cxl: Simplify cxl_root_ops allocation and handling
  cxl/region: Store HPA range in struct cxl_region
  cxl/region: Store root decoder in struct cxl_region
  cxl/region: Rename misleading variable name @hpa to @hpa_range
  Documentation/driver-api/cxl: ACPI PRM Address Translation Support and AMD Zen5 enablement
  cxl, doc: Moving conventions in separate files
  cxl, doc: Remove isonum.txt inclusion
  cxl/port: Unify endpoint and switch port lookup
  cxl/port: Move endpoint component register management to cxl_port
  cxl/port: Map Port RAS registers
  cxl/port: Move dport RAS setup to dport add time
  ...
2026-02-12 16:33:05 -08:00
arch cxl changes for v7.0 2026-02-12 16:33:05 -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 cxl changes for v7.0 2026-02-12 16:33:05 -08:00
drivers cxl changes for v7.0 2026-02-12 16:33:05 -08:00
fs mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -08:00
include cxl changes for v7.0 2026-02-12 16:33:05 -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 cxl changes for v7.0 2026-02-12 16:33:05 -08:00
lib mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -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 mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -08:00
net mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -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 mm.git review status for linus..mm-nonmm-stable 2026-02-12 12:13:01 -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 cxl changes for v7.0 2026-02-12 16:33:05 -08:00
usr kbuild: uapi: drop dependency on CC_CAN_LINK 2026-01-16 15:02:11 -07:00
virt Performance events changes for v7.0: 2026-02-10 12:00:46 -08:00
.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 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 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 VFIO updates for v7.0-rc1 2026-02-12 15:52:39 -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