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Linus Torvalds 57b8e2d666 Arm:
* Allow tracing for non-pKVM, which was accidentally disabled when
   the series was merged
 
 * Rationalise the way the pKVM hypercall ranges are defined by using
   the same mechanism as already used for the vcpu_sysreg enum
 
 * Enforce that SMCCC function numbers relayed by the pKVM proxy are
   actually compliant with the specification
 
 * Fix a couple of feature to idreg mappings which resulted in the
   wrong sanitisation being applied
 
 * Fix the GICD_IIDR revision number field that could never been
   written correctly by userspace
 
 * Make kvm_vcpu_initialized() correctly use its parameter instead
   of relying on the surrounding context
 
 * Enforce correct ordering in __pkvm_init_vcpu(), plugging a
   potential pin leak at the same time
 
 * Move __pkvm_init_finalise() to a less dangerous spot, avoiding
   future problems
 
 * Restore functional userspace irqchip support after a four year
   breakage (last functional kernel was 5.18...).
 
 * Spelling fixes
 
 Selftests:
 
 * Rename types across all KVM selftests to more closely align with types used
   in the kernel:
 
       vm_vaddr_t -> gva_t
       vm_paddr_t -> gpa_t
 
       uint64_t -> u64
       uint32_t -> u32
       uint16_t -> u16
       uint8_t  -> u8
 
       int64_t -> s64
       int32_t -> s32
       int16_t -> s16
       int8_t  -> s8
 
 * Fix Loongarch compilation.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "On top of a lot of Arm fixes, this includes a massive rename of types
  and variables in tools/testing/selftests/kvm - these were
  unnecessarily different from what the kernel uses, so they're being
  made consistent.

  arm64:

   - Allow tracing for non-pKVM, which was accidentally disabled when
     the series was merged

   - Rationalise the way the pKVM hypercall ranges are defined by using
     the same mechanism as already used for the vcpu_sysreg enum

   - Enforce that SMCCC function numbers relayed by the pKVM proxy are
     actually compliant with the specification

   - Fix a couple of feature to idreg mappings which resulted in the
     wrong sanitisation being applied

   - Fix the GICD_IIDR revision number field that could never been
     written correctly by userspace

   - Make kvm_vcpu_initialized() correctly use its parameter instead of
     relying on the surrounding context

   - Enforce correct ordering in __pkvm_init_vcpu(), plugging a
     potential pin leak at the same time

   - Move __pkvm_init_finalise() to a less dangerous spot, avoiding
     future problems

   - Restore functional userspace irqchip support after a four year
     breakage (last functional kernel was 5.18...)

   - Spelling fixes

  Selftests:

   - Rename types across all KVM selftests to more closely align with
     types used in the kernel:

        vm_vaddr_t -> gva_t
        vm_paddr_t -> gpa_t

        uint64_t -> u64
        uint32_t -> u32
        uint16_t -> u16
        uint8_t  -> u8

        int64_t -> s64
        int32_t -> s32
        int16_t -> s16
        int8_t  -> s8

   - Fix Loongarch compilation"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (31 commits)
  KVM: selftests: Add check_steal_time_uapi() implementation for LoongArch
  KVM: arm64: Wake-up from WFI when iqrchip is in userspace
  KVM: arm64: Fix initialisation order in __pkvm_init_finalise()
  KVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu()
  KVM: arm64: Fix kvm_vcpu_initialized() macro parameter
  KVM: arm64: Fix FEAT_SPE_FnE to use PMSIDR_EL1.FnE, not PMSVer
  KVM: arm64: Fix typo in feature check comments
  KVM: arm64: Fix FEAT_Debugv8p9 to check DebugVer, not PMUVer
  KVM: arm64: Reject non compliant SMCCC function calls in pKVM
  KVM: arm64: vgic: Fix IIDR revision field extracted from wrong value
  KVM: selftests: Replace "paddr" with "gpa" throughout
  KVM: selftests: Replace "u64 nested_paddr" with "gpa_t l2_gpa"
  KVM: selftests: Replace "u64 gpa" with "gpa_t" throughout
  KVM: selftests: Replace "vaddr" with "gva" throughout
  KVM: selftests: Clarify that arm64's inject_uer() takes a host PA, not a guest PA
  KVM: selftests: Rename translate_to_host_paddr() => translate_hva_to_hpa()
  KVM: selftests: Rename vm_vaddr_populate_bitmap() => vm_populate_gva_bitmap()
  KVM: selftests: Rename vm_vaddr_unused_gap() => vm_unused_gva_gap()
  KVM: selftests: Drop "vaddr_" from APIs that allocate memory for a given VM
  KVM: selftests: Use u8 instead of uint8_t
  ...
2026-04-29 06:56:50 -07:00
arch KVM/arm64 fixes for 7.1, take #1 2026-04-27 04:24:34 -04:00
block block: only restrict bio allocation gfp mask asked to block 2026-04-21 11:42:12 -06:00
certs Clang build fixes for 7.1 2026-04-24 09:29:51 -07:00
crypto This push contains the following changes: 2026-04-21 08:06:43 -07:00
Documentation cgroup: Fixes for v7.1-rc1 2026-04-27 16:51:27 -07:00
drivers xen: XSA-485 and XSA-487 security patches for v7.1 2026-04-27 18:36:47 -07:00
fs \n 2026-04-27 16:45:39 -07:00
include sched_ext: Fixes for v7.1-rc1 2026-04-28 16:26:11 -07:00
init memblock: updates for 7.0-rc1 2026-04-18 11:29:14 -07:00
io_uring io_uring: take page references for NOMMU pbuf_ring mmaps 2026-04-21 20:14:39 -06:00
ipc Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
kernel sched_ext: Fixes for v7.1-rc1 2026-04-28 16:26:11 -07:00
lib sched_ext: Fixes for v7.1-rc1 2026-04-28 16:26:11 -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
mm slab fix for 7.1 2026-04-24 09:39:03 -07:00
net NFS client updates for Linux 7.1 2026-04-24 14:20:03 -07:00
rust Char/Misc/IIO/and others driver updates for 7.1-rc1 2026-04-24 13:23:50 -07:00
samples soc: drivers for 7.1 2026-04-16 20:34:34 -07:00
scripts First round of Kbuild fixes for 7.1 2026-04-25 17:04:15 -07:00
security + Cleanups 2026-04-24 09:22:21 -07:00
sound sound fixes for 7.1-rc1 2026-04-24 11:49:20 -07:00
tools Arm: 2026-04-29 06:56:50 -07:00
usr kbuild: uapi: also test UAPI headers against C++ compilers 2026-03-25 13:24:42 +01:00
virt Arm: 2026-04-17 07:18:03 -07:00
.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 Char/Misc/IIO/and others driver updates for 7.1-rc1 2026-04-24 13:23:50 -07:00
.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 Char/Misc/IIO/and others driver updates for 7.1-rc1 2026-04-24 13:23:50 -07:00
Makefile Linux 7.1-rc1 2026-04-26 14:19:00 -07:00
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