Linus Torvalds e1914add27 Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
 "arm64:

   - Add the pKVM side of the workaround for ARM's erratum 4193714,
     provided that the EL3 firmware does its part of the job. KVM will
     refuse to initialise otherwise

   - Correctly handle 52bit VAs for guest EL2 stage-1 translations when
     running under NV with E2H==0

   - Correctly deal with permission faults in guest_memfd memslots

   - Fix the steal-time selftest after the infrastructure was reworked

   - Make sure the host cannot pass a non-sensical clock update to the
     EL2 tracing infrastructure

   - Appoint Steffen Eiden as a reviewer in anticipation of the KVM/s390
     ability to run arm64 guests, which will inevitably lead to arm64
     code being directly used on s390

   - Make sure that EL2 is configured with both exception entry and exit
     being Context Synchronization Events

   - Handle the current vcpu being NULL on EL2 panic

   - Fix the selftest_vcpu memcache being empty at the point of donation
     or sharing

   - Check that the memcache has enough capacity before engaging on the
     share/donate path

   - Fix __deactivate_fgt() to use its parameter rather than a variable
     in the macro context

  s390:

   - Fix array overrun with large amounts of PCI devices

  x86:

   - Never use L0's PAUSE loop exiting while L2 is running, since it's
     unlikely that a nested guest will help solving the hypervisor's
     spinlock contention

   - Fix emulation of MOVNTDQA

   - Fix typo in Xen hypercall tracepoint

   - Add back an optimization that was left behind when recently fixing
     a bug

   - Add module parameter to disable CET, whose implementation seems to
     have issues. For now it remains enabled by default

  Generic:

   - Reject offset causing an unsigned overflow in kvm_reset_dirty_gfn()

  Documentation:

   - Update stale links

  Selftests:

   - Fix guest_memfd_test with host page size > guest page size"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (22 commits)
  KVM: VMX: introduce module parameter to disable CET
  KVM: x86: Swap the dst and src operand for MOVNTDQA
  KVM: x86: use again the flush argument of __link_shadow_page()
  KVM: selftests: Ensure gmem file sizes are multiple of host page size
  Documentation: kvm: update links in the references section of AMD Memory Encryption
  KVM: nSVM: Never use L0's PAUSE loop exiting while L2 is running
  KVM: x86: Fix Xen hypercall tracepoint argument assignment
  KVM: Reject wrapped offset in kvm_reset_dirty_gfn()
  KVM: arm64: Pre-check vcpu memcache for host->guest donate
  KVM: arm64: Pre-check vcpu memcache for host->guest share
  KVM: arm64: Seed pkvm_ownership_selftest vcpu memcache
  KVM: arm64: Fix __deactivate_fgt macro parameter typo
  KVM: arm64: Guard against NULL vcpu on VHE hyp panic path
  KVM: arm64: Make EL2 exception entry and exit context-synchronization events
  MAINTAINERS: Add Steffen as reviewer for KVM/arm64
  KVM: arm64: Remove potential UB on nvhe tracing clock update
  KVM: selftests: arm64: Fix steal_time test after UAPI refactoring
  KVM: arm64: Handle permission faults with guest_memfd
  KVM: arm64: nv: Consider the DS bit when translating TCR_EL2
  KVM: arm64: Work around C1-Pro erratum 4193714 for protected guests
  ...
2026-05-13 11:53:51 -07:00
2026-01-26 19:07:09 -08:00
2022-09-28 09:02:20 +02:00
2025-02-19 14:53:27 -07:00
2026-05-10 14:08:09 -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
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