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Linus Torvalds f7c79949be RISC-V updates for v7.1-rc4
- Disable satp register probing when no5lvl is specified on the kernel
   command line
 
 - Fix a CFI-related issue with the misaligned access speed measurement
   code
 
 - Reduce the CFI shadow stack size limit from 4GB to 2GB (following
   ARM64 GCS)
 
 - Prevent the kernel from requesting delegation of misaligned access
   faults unless a new Kconfig option,
   CONFIG_RISCV_SBI_FWFT_DELEGATE_MISALIGNED, is enabled.  This will
   depend on CONFIG_NONPORTABLE until the deficiencies of the kernel
   misaligned access fixup code are fixed
 
 - Fix some potential uninitialized memory accesses in error paths in
   compat_riscv_gpr_set() and compat_restore_sigcontext()
 
 - Fix a bug in the RISC-V MIPS vendor errata patching code where a
   logical-and was used in place of a bitwise-and
 
 - Drop some unnecessary code in riscv_fill_hwcap_from_isa_string()
 
 - Use macros for isa2hwcap indices in riscv_fill_hwcap(), rather than
   open-coding them
 
 - Fix some documentation typos (one affecting "make htmldocs")
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Merge tag 'riscv-for-linus-7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V fixes from Paul Walmsley:
 "Relatively low-impact fixes. Probably the most notable one is that we
  no longer ask the monitor-mode firmware to delegate misaligned access
  handling to the kernel by default, since the kernel code needs
  significant improvement to match the functionality of the firmware.
  This change avoids functional problems at some cost in performance,
  but shouldn't affect any system with misaligned access handling in
  hardware.

   - Disable satp register probing when no5lvl is specified on the
     kernel command line

   - Fix a CFI-related issue with the misaligned access speed
     measurement code

   - Reduce the CFI shadow stack size limit from 4GB to 2GB (following
     ARM64 GCS)

   - Prevent the kernel from requesting delegation of misaligned access
     faults unless a new Kconfig option, RISCV_SBI_FWFT_DELEGATE_MISALIGNED,
     is enabled. This will depend on CONFIG_NONPORTABLE until the
     deficiencies of the kernel misaligned access fixup code are fixed

   - Fix some potential uninitialized memory accesses in error paths in
     compat_riscv_gpr_set() and compat_restore_sigcontext()

   - Fix a bug in the RISC-V MIPS vendor errata patching code where a
     logical-and was used in place of a bitwise-and

   - Drop some unnecessary code in riscv_fill_hwcap_from_isa_string()

   - Use macros for isa2hwcap indices in riscv_fill_hwcap(), rather than
     open-coding them

   - Fix some documentation typos (one affecting 'make htmldocs')"

* tag 'riscv-for-linus-7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: misaligned: Make enabling delegation depend on NONPORTABLE
  riscv: Docs: fix unmatched quote warning
  riscv: cfi: reduce shadow stack size limit from 4GB to 2GB
  riscv: cpufeature: Use pre-defined ISA ext macros to index isa2hwcap
  riscv: mm: Fixup no5lvl failure when vaddr is invalid
  riscv: Fix register corruption from uninitialized cregs on error
  riscv: errata: Fix bitwise vs logical AND in MIPS errata patching
  Documentation: riscv: cmodx: fix typos
  riscv: cpufeature: Drop this_hwcap clear in T-Head vector workaround
  riscv: Define __riscv_copy_{,vec_}{words,bytes}_unaligned() using SYM_TYPED_FUNC_START
2026-05-17 09:33:49 -07:00
Documentation RISC-V updates for v7.1-rc4 2026-05-17 09:33:49 -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
arch RISC-V updates for v7.1-rc4 2026-05-17 09:33:49 -07:00
block block: align down bounces bios 2026-05-13 13:55:18 -06:00
certs Clang build fixes for 7.1 2026-04-24 09:29:51 -07:00
crypto This push contains the following changes: 2026-05-02 12:31:43 -07:00
drivers hwmon fixes for v7.1-rc4 2026-05-17 09:23:28 -07:00
fs five client fixes 2026-05-15 14:52:17 -07:00
include drm fixes for 7.1-rc4 2026-05-15 17:00:45 -07:00
init memblock: updates for 7.0-rc1 2026-04-18 11:29:14 -07:00
io_uring io_uring-7.1-20260515 2026-05-15 12:34:02 -07:00
ipc Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
kernel audit/stable-7.1 PR 20260513 2026-05-14 08:53:24 -07:00
lib This push contains the following changes: 2026-05-15 10:38:37 -07:00
mm This push contains the following changes: 2026-05-15 10:38:37 -07:00
net An important patch from Hristo that squashes a folio reference leak 2026-05-15 14:48:09 -07:00
rust Rust fixes for v7.1 2026-05-09 11:24:02 -07:00
samples soc: drivers for 7.1 2026-04-16 20:34:34 -07:00
scripts gcc-plugins: Always define CONST_CAST_GIMPLE and CONST_CAST_TREE 2026-05-14 09:24:32 -07:00
security selinux: shrink critical section in sel_write_load() 2026-05-05 16:02:28 -04:00
sound ALSA: hda/ca0132: Disable auto-detect on manual output select 2026-05-15 11:19:48 +02:00
tools block-7.1-20260515 2026-05-15 12:47:00 -07:00
usr kbuild: uapi: also test UAPI headers against C++ compilers 2026-03-25 13:24:42 +01:00
virt KVM: Reject wrapped offset in kvm_reset_dirty_gfn() 2026-05-12 22:16:16 +02:00
.clang-format Devicetree updates for v7.0: 2026-02-11 18:27:08 -08:00
.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 kbuild: rust: provide an option to inline C helpers into Rust 2026-03-30 02:03:52 +02:00
.mailmap MAINTAINERS: update Tomasz Jeznach's email address 2026-05-15 07:30:28 +02:00
.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
CREDITS Delete some obsolete networking code 2026-04-24 09:41:58 -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 IOMMU Fixes for Linux v7.1-rc3: 2026-05-15 15:22:26 -07:00
Makefile Linux 7.1-rc3 2026-05-10 14:08:09 -07:00
README docs: add AI Coding Assistants documentation 2026-01-06 14:55:06 -07:00

README

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