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Linus Torvalds 27db1ae6ec Final KVM fixes for 6.19:
- Fix a bug where AVIC is incorrectly inhibited when running with x2AVIC
    disabled via module param (or on a system without x2AVIC).
 
  - Fix a dangling device posted IRQs bug by explicitly checking if the irqfd is
    still active (on the list) when handling an eventfd signal, instead of
    zeroing the irqfd's routing information when the irqfd is deassigned.
    Zeroing the irqfd's routing info causes arm64 and x86's to not disable
    posting for the IRQ (kvm_arch_irq_bypass_del_producer() looks for an MSI),
    incorrectly leaving the IRQ in posted mode (and leading to use-after-free
    and memory leaks on AMD in particular).
 
    This is both the most pressing and scariest, but it's been in -next for
    a while.
 
  - Disable FORTIFY_SOURCE for KVM selftests to prevent the compiler from
    generating calls to the checked versions of memset() and friends, which
    leads to unexpected page faults in guest code due e.g. __memset_chk@plt
    not being resolved.
 
  - Explicitly configure the support XSS from within {svm,vmx}_set_cpu_caps() to
    fix a bug where VMX will compute the reference VMCS configuration with SHSTK
    and IBT enabled, but then compute each CPUs local config with SHSTK and IBT
    disabled if not all CET xfeatures are enabled, e.g. if the kernel is built
    with X86_KERNEL_IBT=n.  The mismatch in features results in differing nVMX
    setting, and ultimately causes kvm-intel.ko to refuse to load with nested=1.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:

 - Fix a bug where AVIC is incorrectly inhibited when running with
   x2AVIC disabled via module param (or on a system without x2AVIC)

 - Fix a dangling device posted IRQs bug by explicitly checking if the
   irqfd is still active (on the list) when handling an eventfd signal,
   instead of zeroing the irqfd's routing information when the irqfd is
   deassigned.

   Zeroing the irqfd's routing info causes arm64 and x86's to not
   disable posting for the IRQ (kvm_arch_irq_bypass_del_producer() looks
   for an MSI), incorrectly leaving the IRQ in posted mode (and leading
   to use-after-free and memory leaks on AMD in particular).

   This is both the most pressing and scariest, but it's been in -next
   for a while.

 - Disable FORTIFY_SOURCE for KVM selftests to prevent the compiler from
   generating calls to the checked versions of memset() and friends,
   which leads to unexpected page faults in guest code due e.g.
   __memset_chk@plt not being resolved.

 - Explicitly configure the supported XSS capabilities from within
   {svm,vmx}_set_cpu_caps() to fix a bug where VMX will compute the
   reference VMCS configuration with SHSTK and IBT enabled, but then
   compute each CPUs local config with SHSTK and IBT disabled if not all
   CET xfeatures are enabled, e.g. if the kernel is built with
   X86_KERNEL_IBT=n.

   The mismatch in features results in differing nVMX setting, and
   ultimately causes kvm-intel.ko to refuse to load with nested=1.

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: Explicitly configure supported XSS from {svm,vmx}_set_cpu_caps()
  KVM: selftests: Add -U_FORTIFY_SOURCE to avoid some unpredictable test failures
  KVM: x86: Assert that non-MSI doesn't have bypass vCPU when deleting producer
  KVM: Don't clobber irqfd routing type when deassigning irqfd
  KVM: SVM: Check vCPU ID against max x2AVIC ID if and only if x2AVIC is enabled
2026-02-04 10:38:56 -08:00
arch Final KVM fixes for 6.19: 2026-02-04 10:38:56 -08:00
block block-6.19-20260122 2026-01-23 12:53:56 -08:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto crypto: authencesn - reject too-short AAD (assoclen<8) to match ESP/ESN spec 2026-01-20 14:38:48 +08:00
Documentation sound fixes for 6.19-rc8 2026-01-31 08:52:41 -08:00
drivers soc: fixes for 6.19, part 3 2026-02-04 08:26:22 -08:00
fs two client memory leak fixes 2026-02-03 16:20:59 -08:00
include Fix a race in the user-callchains code. 2026-02-01 10:47:21 -08:00
init Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
io_uring io_uring-6.19-20260122 2026-01-23 12:51:00 -08:00
ipc Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
kernel cgroup: Fixes for v6.19-rc8 2026-02-02 15:14:45 -08:00
lib mm/zone_device: reinitialize large zone device private folios 2026-01-26 19:03:48 -08:00
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 16 hotfixes. 9 are cc:stable, 12 are for MM. 2026-01-29 11:09:13 -08:00
net net: fix segmentation of forwarding fraglist GRO 2026-01-29 14:40:12 +01:00
rust Rust fixes for v6.19 2026-01-30 16:15:59 -08:00
samples samples/ftrace: Adjust LoongArch register restore order in direct calls 2025-12-31 15:19:25 +08:00
scripts Miscellaneous objtool fixes: 2026-02-01 10:27:43 -08:00
security lsm: preserve /proc/sys/vm/mmap_min_addr when !CONFIG_SECURITY 2026-01-29 13:56:53 -05:00
sound ASoC: Fixes for v6.19 2026-01-29 13:58:06 +01:00
tools Final KVM fixes for 6.19: 2026-02-04 10:38:56 -08:00
usr initramfs: add gen_init_cpio to hostprogs unconditionally 2025-11-26 21:55:40 +01:00
virt KVM: Don't clobber irqfd routing type when deassigning irqfd 2026-01-14 13:17:14 -08:00
.clang-format s390/pci: Fix cyclic dead-lock in zpci_zdev_put() and zpci_scan_devices() 2025-12-14 11:03:58 +01:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: remove Alyssa Rosenzweig 2025-09-18 21:17:31 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore rust: kbuild: add proc macro library support 2025-11-24 17:15:36 +01:00
.mailmap soc: fixes for 6.19, part 3 2026-02-04 08:26:22 -08:00
.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 nfc: MAINTAINERS: Orphan the NFC and look for new maintainers 2026-01-20 16:05:38 -08:00
Kbuild sched: Make migrate_{en,dis}able() inline 2025-09-25 09:57:16 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS soc: fixes for 6.19, part 3 2026-02-04 08:26:22 -08:00
Makefile Linux 6.19-rc8 2026-02-01 14:01:13 -08:00
README README: restructure with role-based documentation and guidelines 2025-11-29 08:40:33 -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


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



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