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Sean Christopherson 9d2180ac56 KVM: x86: Move kvm_caps and kvm_host_values to asm/kvm_host.h
Relocate the kvm_caps and kvm_host_values struct definitions and their
associated global variable declarations to asm/kvm_host.h to allow for a
variety of cleanups in x86.h and mmu.h, and to establish a (hopefully)
maintainable rule that asm/kvm_host.h's role is to define common
structures (and declare any associated globals), and anything needed by
arch-neutral KVM.

While it would be lovely to trim kvm_host.h down to the point where it
*only* holds things needed by arch-neutral and/or non-KVM code, multiple
attempts to do just that have failed miserably.  Trying to "hide" code
from arch-neutral KVM is too restrictive (and ultimately pointless), and
KVM x86 itself also needs a place to define common structures and their
globals, e.g. to avoid inconsistent header include chains and/or misplaced
helpers.

E.g. as pointed out by Kai, it's weird that x86.h, which is a kitchen sink
of sorts, includes regs.h, but not mmu.h.  Literally the only reason that
x86.h doesn't include mmu.h is that mmu.h references kvm_host, which is
currently defined in x86.h.  As a result of odd include ordering, the
very clearly MMU-specific helper mmu_is_nested() lives in x86.h, not mmu.h

"Fix" the kvm_host dependency so that x86.h can be the "central" include
everyone expects it to be, and set KVM x86 on the path to having somewhat
sensible "rules" for what goes where:

  - asm/kvm_host.h holds "common" structure definitions and associated key
    global variables, and things that are referenced by arch-neutral KVM.
  - <thing>.{c,h} holds relevant declarations and definitions.
  - x86.{c,h} is the kitchen sink for everything else.

Cc: Kai Huang <kai.huang@intel.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Reviewed-by: Yosry Ahmed <yosry@kernel.org>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20260613000329.732085-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2026-06-24 08:13:08 -04:00
arch KVM: x86: Move kvm_caps and kvm_host_values to asm/kvm_host.h 2026-06-24 08:13:08 -04:00
block block-7.1-20260529 2026-05-29 10:41:07 -07:00
certs Clang build fixes for 7.1 2026-04-24 09:29:51 -07:00
crypto crypto/krb5, rxrpc: Fix lack of pre-decrypt/pre-verify length checks 2026-05-20 16:36:45 -07:00
Documentation KVM: s390: Fix S390_USER_OPEREXEC and more gmap fixes 2026-06-24 13:41:41 +02:00
drivers KVM: s390: Fix S390_USER_OPEREXEC and more gmap fixes 2026-06-24 13:41:41 +02:00
fs namespace: restrict OPEN_TREE_NAMESPACE/FSMOUNT_NAMESPACE to directories 2026-06-10 07:09:20 -07:00
include KVM: s390: Fix S390_USER_OPEREXEC and more gmap fixes 2026-06-24 13:41:41 +02:00
init memblock: updates for 7.0-rc1 2026-04-18 11:29:14 -07:00
io_uring io_uring-7.1-20260611 2026-06-12 10:49:59 -07:00
ipc ipc/shm: serialize orphan cleanup with shm_nattch updates 2026-06-03 16:25:49 -07:00
kernel dma-mapping fixes for Linux 7.1 2026-06-11 14:22:26 -07:00
lib - Fix potential debugobjects deadlock on PREEMPT_RT kernels 2026-06-13 08:23:36 -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 11 hotfixes. 9 are for MM. 8 are cc:stable and the remaining 3 2026-06-09 08:24:25 -07:00
net netfilter pull request 26-06-10 2026-06-11 12:30:00 +02:00
rust rust: i2c: fix I2cAdapter refcount double increment 2026-06-08 09:47:50 +02:00
samples soc: drivers for 7.1 2026-04-16 20:34:34 -07:00
scripts Rust fixes for v7.1 (2nd) 2026-06-06 09:44:42 -07:00
security security/keys: fix missed RCU read section on lookup 2026-05-28 11:45:41 -07:00
sound ASoC: Fixes for v7.1 2026-06-11 21:29:47 +02:00
tools KVM: s390: Fix S390_USER_OPEREXEC and more gmap fixes 2026-06-24 13:41:41 +02:00
usr kbuild: uapi: also test UAPI headers against C++ compilers 2026-03-25 13:24:42 +01:00
virt KVM: Replace guest-triggerable BUG_ON() in ioeventfd datamatch with get_unaligned() 2026-06-24 11:25:14 +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 Baoquan He's email address 2026-06-03 16:25:50 -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 COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
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 KVM: s390: Fix S390_USER_OPEREXEC and more gmap fixes 2026-06-24 13:41:41 +02:00
Makefile Linux 7.1 2026-06-14 15:58:38 +01:00
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