Go to file
Linus Torvalds 11e8c7e947 ARM:
- Correctly handle deeactivation of interrupts that were activated from
   LRs.  Since EOIcount only denotes deactivation of interrupts that
   are not present in an LR, start EOIcount deactivation walk *after*
   the last irq that made it into an LR.
 
 - Avoid calling into the stubs to probe for ICH_VTR_EL2.TDS when
   pKVM is already enabled -- not only thhis isn't possible (pKVM
   will reject the call), but it is also useless: this can only
   happen for a CPU that has already booted once, and the capability
   will not change.
 
 - Fix a couple of low-severity bugs in our S2 fault handling path,
   affecting the recently introduced LS64 handling and the even more
   esoteric handling of hwpoison in a nested context
 
 - Address yet another syzkaller finding in the vgic initialisation,
   where we would end-up destroying an uninitialised vgic with nasty
   consequences
 
 - Address an annoying case of pKVM failing to boot when some of the
   memblock regions that the host is faulting in are not page-aligned
 
 - Inject some sanity in the NV stage-2 walker by checking the limits
   against the advertised PA size, and correctly report the resulting
   faults
 
 PPC:
 
 - Fix a PPC e500 build error due to a long-standing wart that was exposed by
   the recent conversion to kmalloc_obj(); rip out all the ugliness that
   led to the wart.
 
 RISC-V:
 
 - Prevent speculative out-of-bounds access using array_index_nospec()
   in APLIC interrupt handling, ONE_REG regiser access, AIA CSR access,
   float register access, and PMU counter access
 
 - Fix potential use-after-free issues in kvm_riscv_gstage_get_leaf(),
   kvm_riscv_aia_aplic_has_attr(), and kvm_riscv_aia_imsic_has_attr()
 
 - Fix potential null pointer dereference in kvm_riscv_vcpu_aia_rmw_topei()
 
 - Fix off-by-one array access in SBI PMU
 
 - Skip THP support check during dirty logging
 
 - Fix error code returned for Smstateen and Ssaia ONE_REG interface
 
 - Check host Ssaia extension when creating AIA irqchip
 
 x86:
 
 - Fix cases where CPUID mitigation features were incorrectly marked as
   available whenever the kernel used scattered feature words for them.
 
 - Validate _all_ GVAs, rather than just the first GVA, when processing
   a range of GVAs for Hyper-V's TLB flush hypercalls.
 
 - Fix a brown paper bug in add_atomic_switch_msr().
 
 - Use hlist_for_each_entry_srcu() when traversing mask_notifier_list,
   to fix a lockdep warning; KVM doesn't hold RCU, just irq_srcu.
 
 - Ensure AVIC VMCB fields are initialized if the VM has an in-kernel local
   APIC (and AVIC is enabled at the module level).
 
 - Update CR8 write interception when AVIC is (de)activated, to fix a bug
   where the guest can run in perpetuity with the CR8 intercept enabled.
 
 - Add a quirk to skip the consistency check on FREEZE_IN_SMM, i.e. to allow
   L1 hypervisors to set FREEZE_IN_SMM.  This reverts (by default) an
   unintentional tightening of userspace ABI in 6.17, and provides some
   amount of backwards compatibility with hypervisors who want to freeze
   PMCs on VM-Entry.
 
 - Validate the VMCS/VMCB on return to a nested guest from SMM, because
   either userspace or the guest could stash invalid values in memory
   and trigger the processor's consistency checks.
 
 Generic:
 
 - Remove a subtle pseudo-overlay of kvm_stats_desc, which, aside from being
   unnecessary and confusing, triggered compiler warnings due to
   -Wflex-array-member-not-at-end.
 
 - Document that vcpu->mutex is take outside of kvm->slots_lock and
   kvm->slots_arch_lock, which is intentional and desirable despite being
   rather unintuitive.
 
 Selftests:
 
 - Increase the maximum number of NUMA nodes in the guest_memfd selftest to
   64 (from 8).
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "Quite a large pull request, partly due to skipping last week and
  therefore having material from ~all submaintainers in this one. About
  a fourth of it is a new selftest, and a couple more changes are large
  in number of files touched (fixing a -Wflex-array-member-not-at-end
  compiler warning) or lines changed (reformatting of a table in the API
  documentation, thanks rST).

  But who am I kidding---it's a lot of commits and there are a lot of
  bugs being fixed here, some of them on the nastier side like the
  RISC-V ones.

  ARM:

   - Correctly handle deactivation of interrupts that were activated
     from LRs. Since EOIcount only denotes deactivation of interrupts
     that are not present in an LR, start EOIcount deactivation walk
     *after* the last irq that made it into an LR

   - Avoid calling into the stubs to probe for ICH_VTR_EL2.TDS when pKVM
     is already enabled -- not only thhis isn't possible (pKVM will
     reject the call), but it is also useless: this can only happen for
     a CPU that has already booted once, and the capability will not
     change

   - Fix a couple of low-severity bugs in our S2 fault handling path,
     affecting the recently introduced LS64 handling and the even more
     esoteric handling of hwpoison in a nested context

   - Address yet another syzkaller finding in the vgic initialisation,
     where we would end-up destroying an uninitialised vgic with nasty
     consequences

   - Address an annoying case of pKVM failing to boot when some of the
     memblock regions that the host is faulting in are not page-aligned

   - Inject some sanity in the NV stage-2 walker by checking the limits
     against the advertised PA size, and correctly report the resulting
     faults

  PPC:

   - Fix a PPC e500 build error due to a long-standing wart that was
     exposed by the recent conversion to kmalloc_obj(); rip out all the
     ugliness that led to the wart

  RISC-V:

   - Prevent speculative out-of-bounds access using array_index_nospec()
     in APLIC interrupt handling, ONE_REG regiser access, AIA CSR
     access, float register access, and PMU counter access

   - Fix potential use-after-free issues in kvm_riscv_gstage_get_leaf(),
     kvm_riscv_aia_aplic_has_attr(), and kvm_riscv_aia_imsic_has_attr()

   - Fix potential null pointer dereference in
     kvm_riscv_vcpu_aia_rmw_topei()

   - Fix off-by-one array access in SBI PMU

   - Skip THP support check during dirty logging

   - Fix error code returned for Smstateen and Ssaia ONE_REG interface

   - Check host Ssaia extension when creating AIA irqchip

  x86:

   - Fix cases where CPUID mitigation features were incorrectly marked
     as available whenever the kernel used scattered feature words for
     them

   - Validate _all_ GVAs, rather than just the first GVA, when
     processing a range of GVAs for Hyper-V's TLB flush hypercalls

   - Fix a brown paper bug in add_atomic_switch_msr()

   - Use hlist_for_each_entry_srcu() when traversing mask_notifier_list,
     to fix a lockdep warning; KVM doesn't hold RCU, just irq_srcu

   - Ensure AVIC VMCB fields are initialized if the VM has an in-kernel
     local APIC (and AVIC is enabled at the module level)

   - Update CR8 write interception when AVIC is (de)activated, to fix a
     bug where the guest can run in perpetuity with the CR8 intercept
     enabled

   - Add a quirk to skip the consistency check on FREEZE_IN_SMM, i.e. to
     allow L1 hypervisors to set FREEZE_IN_SMM. This reverts (by
     default) an unintentional tightening of userspace ABI in 6.17, and
     provides some amount of backwards compatibility with hypervisors
     who want to freeze PMCs on VM-Entry

   - Validate the VMCS/VMCB on return to a nested guest from SMM,
     because either userspace or the guest could stash invalid values in
     memory and trigger the processor's consistency checks

  Generic:

   - Remove a subtle pseudo-overlay of kvm_stats_desc, which, aside from
     being unnecessary and confusing, triggered compiler warnings due to
     -Wflex-array-member-not-at-end

   - Document that vcpu->mutex is take outside of kvm->slots_lock and
     kvm->slots_arch_lock, which is intentional and desirable despite
     being rather unintuitive

  Selftests:

   - Increase the maximum number of NUMA nodes in the guest_memfd
     selftest to 64 (from 8)"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (43 commits)
  KVM: selftests: Verify SEV+ guests can read and write EFER, CR0, CR4, and CR8
  Documentation: kvm: fix formatting of the quirks table
  KVM: x86: clarify leave_smm() return value
  selftests: kvm: add a test that VMX validates controls on RSM
  selftests: kvm: extract common functionality out of smm_test.c
  KVM: SVM: check validity of VMCB controls when returning from SMM
  KVM: VMX: check validity of VMCS controls when returning from SMM
  KVM: SVM: Set/clear CR8 write interception when AVIC is (de)activated
  KVM: SVM: Initialize AVIC VMCB fields if AVIC is enabled with in-kernel APIC
  KVM: x86: Introduce KVM_X86_QUIRK_VMCS12_ALLOW_FREEZE_IN_SMM
  KVM: x86: Fix SRCU list traversal in kvm_fire_mask_notifiers()
  KVM: VMX: Fix a wrong MSR update in add_atomic_switch_msr()
  KVM: x86: hyper-v: Validate all GVAs during PV TLB flush
  KVM: x86: synthesize CPUID bits only if CPU capability is set
  KVM: PPC: e500: Rip out "struct tlbe_ref"
  KVM: PPC: e500: Fix build error due to using kmalloc_obj() with wrong type
  KVM: selftests: Increase 'maxnode' for guest_memfd tests
  KVM: arm64: pkvm: Don't reprobe for ICH_VTR_EL2.TDS on CPU hotplug
  KVM: arm64: vgic: Pick EOIcount deactivations from AP-list tail
  KVM: arm64: Remove the redundant ISB in __kvm_at_s1e2()
  ...
2026-03-15 12:22:10 -07:00
Documentation ARM: 2026-03-15 12:22:10 -07:00
LICENSES
arch ARM: 2026-03-15 12:22:10 -07:00
block block-7.0-20260305 2026-03-06 08:36:18 -08:00
certs Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
crypto crypto: testmgr - Fix stale references to aes-generic 2026-03-03 11:57:15 -08:00
drivers Two fixes for the riscv-aplic irqchip driver: 2026-03-15 10:32:57 -07:00
fs A small pile of CephFS and messenger bug fixes, all marked for stable. 2026-03-13 14:03:58 -07:00
include ARM: 2026-03-15 12:22:10 -07:00
init io_uring-7.0-20260305 2026-03-06 08:31:36 -08:00
io_uring io_uring-7.0-20260312 2026-03-13 10:09:35 -07:00
ipc Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
kernel Fix function tracer recursion bug by marking jiffies_64_to_clock_t() 2026-03-15 11:14:09 -07:00
lib linux_kselftest-kunit-fixes-7.0-rc3 2026-03-06 12:34:49 -08:00
mm slab fixes for 7.0-rc3 2026-03-13 10:07:33 -07:00
net A small pile of CephFS and messenger bug fixes, all marked for stable. 2026-03-13 14:03:58 -07:00
rust Rust fixes for v7.0 (2nd) 2026-03-14 12:35:16 -07:00
samples drm-fixes for 7.0-rc4 2026-03-13 15:38:55 -07:00
scripts Hi Dave and Sima, 2026-03-13 10:40:17 +10:00
security apparmor: fix race between freeing data and fs accessing it 2026-03-09 16:05:44 -07:00
sound ASoC: Fixes for v7.0 2026-03-12 12:59:28 +01:00
tools ARM: 2026-03-15 12:22:10 -07:00
usr
virt KVM generic changes for 7.0 2026-03-11 18:01:55 +01:00
.clang-format Devicetree updates for v7.0: 2026-02-11 18:27:08 -08:00
.clippy.toml
.cocciconfig
.editorconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap 15 hotfixes. 6 are cc:stable. 14 are for MM. 2026-03-10 12:47:56 -07:00
.pylintrc
.rustfmt.toml
COPYING
CREDITS MAINTAINERS: remove Thomas Falcon from IBM ibmvnic 2026-03-05 07:35:45 -08:00
Kbuild
Kconfig
MAINTAINERS drm-fixes for 7.0-rc4 2026-03-13 15:38:55 -07:00
Makefile Rust fixes for v7.0 (2nd) 2026-03-14 12:35:16 -07:00
README

README

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