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Linus Torvalds 5ccda18d1b Perf events fixes:
- Fixes for KVM guest PEBS virtualization (Sean Christopherson)
 
  - Fixes for various Intel PMUs related to PEBS data-source
    (Dapeng Mi)
 
  - Fix Intel Panther Cove event scheduling constraints (Dapeng Mi)
 
  - Fix Intel DMR/NVL OMR extra registers event scheduling (Dapeng Mi)
 
  - Rename two confusingly named PMU attributes (Dapeng Mi)
 
  - Fix a refcount leak in attach_perf_ctx_data() (Namhyung Kim)
 
  - Fix NULL pointer dereference crash in __perf_pmu_sched_task()
    (Puranjay Mohan)
 
  - Fix CPU-wide event scheduling (Puranjay Mohan)
 
  - Fix x86 LBR branch entry generation (Puranjay Mohan)
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'perf-urgent-2026-09-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf events fixes from Ingo Molnar:

 - Fixes for KVM guest PEBS virtualization (Sean Christopherson)

 - Fixes for various Intel PMUs related to PEBS data-source (Dapeng Mi)

 - Fix Intel Panther Cove event scheduling constraints (Dapeng Mi)

 - Fix Intel DMR/NVL OMR extra registers event scheduling (Dapeng Mi)

 - Rename two confusingly named PMU attributes (Dapeng Mi)

 - Fix a refcount leak in attach_perf_ctx_data() (Namhyung Kim)

 - Fix NULL pointer dereference crash in __perf_pmu_sched_task()
   (Puranjay Mohan)

 - Fix CPU-wide event scheduling (Puranjay Mohan)

 - Fix x86 LBR branch entry generation (Puranjay Mohan)

* tag 'perf-urgent-2026-09-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Fill branch entries with a single assignment
  perf/core: Run sched_task() for PMUs with only CPU-wide events
  perf/core: Fix NULL pmu_ctx passed to pmu->sched_task()
  perf/core: Fix a refcount leak in attach_perf_ctx_data()
  perf/x86/intel: Rename NVL offcore_rsp attribute to offmodule_rsp
  perf/x86/intel: Rename DMR offcore_rsp attribute to offmodule_rsp
  perf/x86/intel: Fix precise OMR event scheduling for DMR/NVL
  perf/x86/intel: Constrain Panther Cove UOPS_DISPATCHED events to PMCs 0-3
  perf/x86/intel: Delete dead NVL PEBS data-source initcall
  perf/x86/intel: Fix Panther Cove PEBS data-source snoop states
  perf/x86/intel: Remove incorrect Panther Cove PEBS data-source constraints
  perf/x86/intel: Remove incorrect LionCove PEBS data-source constraints
  perf/x86/intel: Update arw_latency_data() mem-op direction handling
  perf/x86/intel: Fix DKT PEBS load/store direction for latency events, to fix sample classification
  perf/x86/intel: Fix CMT PEBS load/store direction for latency events, to fix sample classification
  perf/x86/intel: Fix GRT PEBS load/store direction for latency events, to fix sample classification
  perf/x86/intel: Make @data a mandatory param for intel_guest_get_msrs()
  perf/x86/intel: Don't pointlessly context switch DS_AREA (and PEBS config) if PEBS is unused
  perf/x86/intel: Don't write PEBS_ENABLED on host<=>guest xfers if CPU has PEBS isolation, to fix stuck PEBS_ENABLED
  perf/x86/intel: Ensure KVM guest PEBS path doesn't set unwanted PERF_GLOBAL_CTRL bits
2026-09-27 08:15:58 -07:00
arch Perf events fixes: 2026-09-27 08:15:58 -07:00
block SCSI fixes on 20260925 2026-09-25 14:41:52 -07:00
certs treewide: fix indentation and whitespace in Kconfig files 2026-05-28 21:24:42 -07:00
crypto This push fixes a memory allocation overrun in crypto acomp. 2026-08-28 09:28:40 -07:00
Documentation ata fixes for 7.3-rc5 2026-09-26 11:14:35 -07:00
drivers Perf events fixes: 2026-09-27 08:15:58 -07:00
fs smb client fixes for v7.3-rc5 2026-09-25 13:30:04 -07:00
include Perf events fixes: 2026-09-27 08:15:58 -07:00
init Bootconfig fixes for v7.3-rc3 2026-09-13 09:16:36 -07:00
io_uring io_uring-7.3-20260911 2026-09-11 12:36:13 -07:00
ipc mm.git review status for master..mm-nonmm-stable 2026-08-23 08:07:11 -07:00
kernel Perf events fixes: 2026-09-27 08:15:58 -07:00
lib 14 hotfixes. 10 are cc:stable. 11 are for MM. 2026-09-14 08:59:09 -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 memblock: add missing HugeTLB flag name 2026-09-24 06:16:19 -07:00
net Including fixes from Bluetooth, NFC and Netfilter. 2026-09-24 11:45:33 -07:00
rust Including fixes from Netfilter, Bluetooth, IPSec and WiFi. 2026-09-17 10:40:48 -07:00
samples rust: samples: add missing newlines in rust_print_main 2026-09-01 02:20:22 +02:00
scripts hid-for-linus-2026092202 2026-09-22 10:30:17 -07:00
security ipe/stable-7.3 PR 20260925 2026-09-25 15:55:03 -07:00
sound ASoC: Fixes for v7.3 2026-09-17 08:15:32 +02:00
tools Probes fixes for v7.3-rc4: 2026-09-26 08:36:29 -07:00
usr usr: Correct a spelling by changing a letter 2026-08-05 14:51:58 +02:00
virt KVM: Don't pre-reserve xarray entries when storing empty/NULL attributes 2026-09-22 08:36:16 -07:00
.clang-format drm/bridge: rename drm_for_each_bridge_in_chain_scoped() to drm_for_each_bridge_in_chain() 2026-07-14 17:55:51 +02:00
.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 2026-09-07 10:01:33 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore SPDX patches for 7.2-rc1 2026-06-22 12:06:22 -07:00
.mailmap Including fixes from Bluetooth, NFC and Netfilter. 2026-09-24 11:45:33 -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 Driver core fixes for 7.3-rc2 2026-09-05 11:59:05 -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 ata fixes for 7.3-rc5 2026-09-26 11:14:35 -07:00
Makefile Linux 7.3-rc4 2026-09-20 13:48:15 -07:00
README README: remove out of place emdashes 2026-07-15 10:51:29 -06:00

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