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Linus Torvalds 2e973d4882 Updates for interrupt chip drivers:
- Remove the futile attempts to cleanup resources when the probing of the
     main interrupt chip fails for SiFIVE/PLIC devices. If that probe fails
     the system will stall immediately afterwards in the boot process
     without reaching a state where the error could be diagnosed. The lack
     of resource cleanup led to a frenzy of AI detected/assisted "fixes"
     which just make the code pretend to be correct for no value.
 
     Remove the existing half baked cleanup and immediately panic the
     machine when the probe fails. That's far more useful than letting it
     proceed and stall out a millisecond later with no information about the
     root cause.
 
   - A series of fixes for the ARM GIC-V3 driver addressing a potential
     double free, a bitmask overrun on 32-bit ARM and a OF node leak.
 
   - Automatically set the IRQ_DOMAIN_FLAG_DESTROY_GC when a interrupt
     domain is created that also allocates the generic interrupt chip during
     domain creation. That removes the requirement for manually setting the
     flag in the domain creation info structure when it contains a valid
     entry for allocating the generic interrupt chip. Remove the therefore
     redundant setters of IRQ_DOMAIN_FLAG_DESTROY_GC in the existing
     drivers.
 
   - Add support for Annapurna Labs FIC version 2 and 3 and implement
     affinity control for the demultiplexed interrupts by utilizing the
     recently merged interrupt redirection infrastructure.
 
   - Convert the ACPI device ID structures to named initializers
 
   - Consolidate the IPI related constants for RISC-V interrupt controllers
 
   - Add support for Qualcomm Purwa SoC interrupt chip and consolidate the
     workaround for the previous version in Hamoa SoCs.
 
   - The usual small fixes and improvements all over the place
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Merge tag 'irq-drivers-2026-10-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq chip driver updates from Thomas Gleixner:
 "Updates for interrupt chip drivers:

   - Remove the futile attempts to cleanup resources when the probing of
     the main interrupt chip fails for SiFIVE/PLIC devices. If that
     probe fails the system will stall immediately afterwards in the
     boot process without reaching a state where the error could be
     diagnosed. The lack of resource cleanup led to a frenzy of AI
     detected/assisted "fixes" which just make the code pretend to be
     correct for no value.

     Remove the existing half baked cleanup and immediately panic the
     machine when the probe fails. That's far more useful than letting
     it proceed and stall out a millisecond later with no information
     about the root cause.

   - A series of fixes for the ARM GIC-V3 driver addressing a potential
     double free, a bitmask overrun on 32-bit ARM and a OF node leak.

   - Automatically set the IRQ_DOMAIN_FLAG_DESTROY_GC when a interrupt
     domain is created that also allocates the generic interrupt chip
     during domain creation. That removes the requirement for manually
     setting the flag in the domain creation info structure when it
     contains a valid entry for allocating the generic interrupt chip.
     Remove the therefore redundant setters of
     IRQ_DOMAIN_FLAG_DESTROY_GC in the existing drivers.

   - Add support for Annapurna Labs FIC version 2 and 3 and implement
     affinity control for the demultiplexed interrupts by utilizing the
     recently merged interrupt redirection infrastructure.

   - Convert the ACPI device ID structures to named initializers

   - Consolidate the IPI related constants for RISC-V interrupt
     controllers

   - Add support for Qualcomm Purwa SoC interrupt chip and consolidate
     the workaround for the previous version in Hamoa SoCs.

   - The usual small fixes and improvements all over the place"

* tag 'irq-drivers-2026-10-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (61 commits)
  irqchip/al-fic: Support per-child affinity via interrupt redirection
  irqchip/al-fic: Add support for FIC v3
  irqchip/al-fic: Support error and fatal outputs and FIC v2
  dt-bindings: interrupt-controller: amazon,al-fic: Add mask selection
  irqchip/al-fic: Switch to shared parent interrupt
  irqchip/al-fic: Keep the device_node instead of a cached name string
  irqchip/al-fic: Use %pOF and raise init log level
  irqchip/al-fic: Use %pe to print init error
  irqchip/al-fic: Fix coding style issues
  irqchip: Use named initializers for acpi_device_id
  irqchip/gic-v5: Fix standalone IRSes OF probe
  dt-bindings: interrupt-controller: gicv5: Relax IRS properties constraints
  irqchip/renesas-rzv2h: Preserve TIEN state in rzv2h_tint_set_type()
  irqchip/loongson-eiointc: Use pa_to_nid() rather than hard-code
  irqchip/riscv-imsic: Expose the fwnode via the global config
  irqchip/meson-gpio: Allow the GPIO interrupts to wake the system
  irqchip/gic-v3: Ensure change to DS is visible
  irqchip/mips-gic: Transfer interrupt mask state across clusters
  irqchip/mips-gic: Fix recursive acquisition of gic_lock in gic_set_affinity()
  irqchip/mips-gic: Fix unbalanced cm_core_lock in for_each_online_cpu_gic()
  ...
2026-10-21 11:16:50 -10:00
arch Updates for interrupt chip drivers: 2026-10-21 11:16:50 -10:00
block vfs-7.4-rc1.iomap 2026-10-19 18:33:02 -10:00
certs treewide: fix indentation and whitespace in Kconfig files 2026-05-28 21:24:42 -07:00
crypto lib/crypto: sparc/aes-xts: Add optimization using the AES opcodes 2026-10-04 21:40:47 +02:00
Documentation Updates for interrupt chip drivers: 2026-10-21 11:16:50 -10:00
drivers Updates for interrupt chip drivers: 2026-10-21 11:16:50 -10:00
fs Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
include Updates for interrupt chip drivers: 2026-10-21 11:16:50 -10:00
init Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
io_uring vfs-7.4-rc1.file 2026-10-19 17:35:50 -10:00
ipc vfs-7.4-rc1.idmap 2026-10-19 17:57:49 -10:00
kernel Updates for interrupt chip drivers: 2026-10-21 11:16:50 -10:00
lib Report CSD-lock stall recovery time 2026-10-21 11:03:28 -10:00
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 \n 2026-10-20 16:30:13 -10:00
net Merge __{get,put}_user() removal branch 2026-10-21 07:19:30 -10:00
rust Rust changes for v7.4 2026-10-21 10:20:36 -10:00
samples configfs: Updates for v7.4 2026-10-20 16:25:43 -10:00
scripts Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
security lsm/stable-7.4 PR 20261016 2026-10-20 20:04:07 -10:00
sound ASoC: amd: yc: disable MSI on resume 2026-10-13 14:32:22 +01:00
tools Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
usr Merge branch 'kbuild-next-speedups' into kbuild-next 2026-10-17 15:20:23 -07:00
virt vfs-7.4-rc1.idmap 2026-10-19 17:57:49 -10:00
.clang-format drm/bridge: rename drm_for_each_bridge_in_chain_scoped() to drm_for_each_bridge_in_chain() 2026-07-14 17:55:51 +02:00
.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 2026-09-07 10:01:33 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore .gitignore: drop Module.markers 2026-10-04 18:18:08 +02:00
.mailmap Changes since last update: 2026-10-20 16:50:37 -10:00
.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
AGENTS.md docs: add AGENTS.md as a symlink to README 2026-10-14 11:45:46 -06:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS vfs-7.4-rc1.bfs 2026-10-19 16:55:31 -10:00
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 Updates for interrupt chip drivers: 2026-10-21 11:16:50 -10:00
Makefile Kbuild / Kconfig updates for 7.4 2026-10-21 10:45:44 -10:00
README README: remove out of place emdashes 2026-07-15 10:51:29 -06:00

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