Commit Graph

440 Commits

Author SHA1 Message Date
Linus Torvalds
72c395024d Merge tag 'docs-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux
Pull documentation updates from Jonathan Corbet:
 "A slightly calmer cycle for docs this time around, though there is
  still a fair amount going on, including:

   - Some signs of life on the long-moribund Japanese translation

   - Documentation on policies around the use of generative tools for
     patch submissions, and a separate document intended for consumption
     by generative tools

   - The completion of the move of the documentation tools to
     tools/docs. For now we're leaving a /scripts/kernel-doc symlink
     behind to avoid breaking scripts

   - Ongoing build-system work includes the incorporation of
     documentation in Python code, better support for documenting
     variables, and lots of improvements and fixes

   - Automatic linking of man-page references -- cat(1), for example --
     to the online pages in the HTML build

  ...and the usual array of typo fixes and such"

* tag 'docs-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux: (107 commits)
  doc: development-process: add notice on testing
  tools: sphinx-build-wrapper: improve its help message
  docs: sphinx-build-wrapper: allow -v override -q
  docs: kdoc: Fix pdfdocs build for tools
  docs: ja_JP: process: translate 'Obtain a current source tree'
  docs: fix 're-use' -> 'reuse' in documentation
  docs: ioctl-number: fix a typo in ioctl-number.rst
  docs: filesystems: ensure proc pid substitutable is complete
  docs: automarkup.py: Skip common English words as C identifiers
  Documentation: use a source-read extension for the index link boilerplate
  docs: parse_features: make documentation more consistent
  docs: add parse_features module documentation
  docs: jobserver: do some documentation improvements
  docs: add jobserver module documentation
  docs: kabi: helpers: add documentation for each "enum" value
  docs: kabi: helpers: add helper for debug bits 7 and 8
  docs: kabi: system_symbols: end docstring phrases with a dot
  docs: python: abi_regex: do some improvements at documentation
  docs: python: abi_parser: do some improvements at documentation
  docs: add kabi modules documentation
  ...
2026-02-09 20:53:18 -08:00
Linus Torvalds
45bf4bc87c Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
 "There's a little less than normal, probably due to LPC & Christmas/New
  Year meaning that a few series weren't quite ready or reviewed in
  time. It's still useful across the board, despite the only real
  feature being support for the LS64 feature enabling 64-byte atomic
  accesses to endpoints that support it.

  ACPI:
   - Add interrupt signalling support to the AGDI handler
   - Add Catalin and myself to the arm64 ACPI MAINTAINERS entry

  CPU features:
   - Drop Kconfig options for PAN and LSE (these are detected at runtime)
   - Add support for 64-byte single-copy atomic instructions (LS64/LS64V)
   - Reduce MTE overhead when executing in the kernel on Ampere CPUs
   - Ensure POR_EL0 value exposed via ptrace is up-to-date
   - Fix error handling on GCS allocation failure

  CPU frequency:
   - Add CPU hotplug support to the FIE setup in the AMU driver

  Entry code:
   - Minor optimisations and cleanups to the syscall entry path
   - Preparatory rework for moving to the generic syscall entry code

  Hardware errata:
   - Work around Spectre-BHB on TSV110 processors
   - Work around broken CMO propagation on some systems with the SI-L1
     interconnect

  Miscellaneous:
   - Disable branch profiling for arch/arm64/ to avoid issues with
     noinstr
   - Minor fixes and cleanups (kexec + ubsan, WARN_ONCE() instead of
     WARN_ON(), reduction of boolean expression)
   - Fix custom __READ_ONCE() implementation for LTO builds when
     operating on non-atomic types

  Perf and PMUs:
   - Support for CMN-600AE
   - Be stricter about supported hardware in the CMN driver
   - Support for DSU-110 and DSU-120
   - Support for the cycles event in the DSU driver (alongside the
     dedicated cycles counter)
   - Use IRQF_NO_THREAD instead of IRQF_ONESHOT in the cxlpmu driver
   - Use !bitmap_empty() as a faster alternative to bitmap_weight()
   - Fix SPE error handling when failing to resume profiling

  Selftests:
   - Add support for the FORCE_TARGETS option to the arm64 kselftests
   - Avoid nolibc-specific my_syscall() function
   - Add basic test for the LS64 HWCAP
   - Extend fp-pidbench to cover additional workload patterns"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (43 commits)
  perf/arm-cmn: Reject unsupported hardware configurations
  perf: arm_spe: Properly set hw.state on failures
  arm64/gcs: Fix error handling in arch_set_shadow_stack_status()
  arm64: Fix non-atomic __READ_ONCE() with CONFIG_LTO=y
  arm64: poe: fix stale POR_EL0 values for ptrace
  kselftest/arm64: Raise default number of loops in fp-pidbench
  kselftest/arm64: Add a no-SVE loop after SVE in fp-pidbench
  perf/cxlpmu: Replace IRQF_ONESHOT with IRQF_NO_THREAD
  arm64: mte: Set TCMA1 whenever MTE is present in the kernel
  arm64/ptrace: Return early for ptrace_report_syscall_entry() error
  arm64/ptrace: Split report_syscall()
  arm64: Remove unused _TIF_WORK_MASK
  kselftest/arm64: Add missing file in .gitignore
  arm64: errata: Workaround for SI L1 downstream coherency issue
  kselftest/arm64: Add HWCAP test for FEAT_LS64
  arm64: Add support for FEAT_{LS64, LS64_V}
  KVM: arm64: Enable FEAT_{LS64, LS64_V} in the supported guest
  arm64: Provide basic EL2 setup for FEAT_{LS64, LS64_V} usage at EL0/1
  KVM: arm64: Handle DABT caused by LS64* instructions on unsupported memory
  KVM: arm64: Add documentation for KVM_EXIT_ARM_LDST64B
  ...
2026-02-09 20:28:45 -08:00
Linus Torvalds
c48953d819 Merge tag 's390-7.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Heiko Carstens:

 - Drop support for outdated 3590/3592 and 3480 tape devices, and limit
   support to virtualized 3490E types devices

 - Implement exception based WARN() and WARN_ONCE() similar to x86

 - Slightly optimize preempt primitives like __preempt_count_add() and
   __preempt_count_dec_and_test()

 - A couple of small fixes and improvements

* tag 's390-7.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (35 commits)
  s390/tape: Consolidate tape config options and modules
  s390/cio: Fix device lifecycle handling in css_alloc_subchannel()
  s390/tape: Rename tape_34xx.c to tape_3490.c
  s390/tape: Cleanup sense data analysis and error handling
  s390/tape: Remove 3480 tape device type
  s390/tape: Remove unused command definitions
  s390/tape: Remove special block id handling
  s390/tape: Remove tape load display support
  s390/tape: Remove support for 3590/3592 models
  s390/kexec: Emit an error message when cmdline is too long
  s390/configs: Enable BLK_DEV_NULL_BLK as module
  s390: Document s390 stackprotector support
  s390/perf: Disable register readout on sampling events
  s390/Kconfig: Define non-zero ILLEGAL_POINTER_VALUE
  s390/bug: Prevent tail-call optimization
  s390/bug: Skip __WARN_trap() in call traces
  s390/bug: Implement WARN_ONCE()
  s390/bug: Implement __WARN_printf()
  s390/traps: Copy monitor code to pt_regs
  s390/bug: Introduce and use monitor code macro
  ...
2026-02-09 20:17:03 -08:00
Linus Torvalds
d16738a4e7 Merge tag 'kthread-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks
Pull kthread updates from Frederic Weisbecker:
 "The kthread code provides an infrastructure which manages the
  preferred affinity of unbound kthreads (node or custom cpumask)
  against housekeeping (CPU isolation) constraints and CPU hotplug
  events.

  One crucial missing piece is the handling of cpuset: when an isolated
  partition is created, deleted, or its CPUs updated, all the unbound
  kthreads in the top cpuset become indifferently affine to _all_ the
  non-isolated CPUs, possibly breaking their preferred affinity along
  the way.

  Solve this with performing the kthreads affinity update from cpuset to
  the kthreads consolidated relevant code instead so that preferred
  affinities are honoured and applied against the updated cpuset
  isolated partitions.

  The dispatch of the new isolated cpumasks to timers, workqueues and
  kthreads is performed by housekeeping, as per the nice Tejun's
  suggestion.

  As a welcome side effect, HK_TYPE_DOMAIN then integrates both the set
  from boot defined domain isolation (through isolcpus=) and cpuset
  isolated partitions. Housekeeping cpumasks are now modifiable with a
  specific RCU based synchronization. A big step toward making
  nohz_full= also mutable through cpuset in the future"

* tag 'kthread-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks: (33 commits)
  doc: Add housekeeping documentation
  kthread: Document kthread_affine_preferred()
  kthread: Comment on the purpose and placement of kthread_affine_node() call
  kthread: Honour kthreads preferred affinity after cpuset changes
  sched/arm64: Move fallback task cpumask to HK_TYPE_DOMAIN
  sched: Switch the fallback task allowed cpumask to HK_TYPE_DOMAIN
  kthread: Rely on HK_TYPE_DOMAIN for preferred affinity management
  kthread: Include kthreadd to the managed affinity list
  kthread: Include unbound kthreads in the managed affinity list
  kthread: Refine naming of affinity related fields
  PCI: Remove superfluous HK_TYPE_WQ check
  sched/isolation: Remove HK_TYPE_TICK test from cpu_is_isolated()
  cpuset: Remove cpuset_cpu_is_isolated()
  timers/migration: Remove superfluous cpuset isolation test
  cpuset: Propagate cpuset isolation update to timers through housekeeping
  cpuset: Propagate cpuset isolation update to workqueue through housekeeping
  PCI: Flush PCI probe workqueue on cpuset isolated partition change
  sched/isolation: Flush vmstat workqueues on cpuset isolated partition change
  sched/isolation: Flush memcg workqueues on cpuset isolated partition change
  cpuset: Update HK_TYPE_DOMAIN cpumask from cpuset
  ...
2026-02-09 19:57:30 -08:00
Frederic Weisbecker
79c0abaf06 sched/arm64: Move fallback task cpumask to HK_TYPE_DOMAIN
When none of the allowed CPUs of a task are online, it gets migrated
to the fallback cpumask which is all the non nohz_full CPUs.

However just like nohz_full CPUs, domain isolated CPUs don't want to be
disturbed by tasks that have lost their CPU affinities.

And since nohz_full rely on domain isolation to work correctly, the
housekeeping mask of domain isolated CPUs should always be a subset of
the housekeeping mask of nohz_full CPUs (there can be CPUs that are
domain isolated but not nohz_full, OTOH there shouldn't be nohz_full
CPUs that are not domain isolated):

	HK_TYPE_DOMAIN & HK_TYPE_KERNEL_NOISE == HK_TYPE_DOMAIN

Therefore use HK_TYPE_DOMAIN as the appropriate fallback target for
tasks. Note that cpuset isolated partitions are not supported on those
systems and may result in undefined behaviour.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Waiman Long <longman@redhat.com>
Acked-by: Will Deacon <will@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marco Crivellari <marco.crivellari@suse.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
2026-02-03 15:23:35 +01:00
Rhys Tumelty
78a00cac1e docs: fix 're-use' -> 'reuse' in documentation
Signed-off-by: Rhys Tumelty <rhys@tumelty.co.uk>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260128220233.179439-1-rhys@tumelty.co.uk>
2026-02-02 09:54:15 -07:00
Will Deacon
2f8aed5e97 Merge branch 'for-next/errata' into for-next/core
* for-next/errata:
  arm64: errata: Workaround for SI L1 downstream coherency issue
2026-01-29 12:05:33 +00:00
Gerd Bayer
0d453ba040 s390/Kconfig: Define non-zero ILLEGAL_POINTER_VALUE
Define CONFIG_ILLEGAL_POINTER_VALUE to the eye-catching non-zero value
of 0xdead000000000000, consistent with other architectures. Assert at
compile-time that the poison pointers that include/linux/poison.h
defines based on this illegal pointer are beyond the largest useful
virtual addresses. Also, assert at compile-time that the range of poison
pointers per include/linux/poison.h (currently a range of less than
0x10000 addresses) does not overlap with the range used for address
handles for s390's non-MIO PCI instructions.

This enables s390 to track the DMA mappings by the network stack's
page_pool that was introduced with [0]. Other functional changes are not
intended.

Other archictectures have introduced this for various other reasons with
commit 5c178472af ("riscv: define ILLEGAL_POINTER_VALUE for 64bit")
commit f6853eb561 ("powerpc/64: Define ILLEGAL_POINTER_VALUE for 64-bit")
commit bf0c4e0473 ("arm64: kconfig: Move LIST_POISON to a safe value")
commit a29815a333 ("core, x86: make LIST_POISON less deadly")

[0] https://lore.kernel.org/all/20250409-page-pool-track-dma-v9-0-6a9ef2e0cba8@redhat.com/

Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Gerd Bayer <gbayer@linux.ibm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-01-27 12:21:20 +01:00
Linus Torvalds
d91a46d680 Merge tag 'riscv-for-linus-6.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Paul Walmsley:
 "The notable changes here are the three RISC-V timer compare register
  update sequence patches. These only apply to RV32 systems and are
  related to the 64-bit timer compare value being split across two
  separate 32-bit registers.

  We weren't using the appropriate three-write sequence, documented in
  the RISC-V ISA specifications, to avoid spurious timer interrupts
  during the update sequence; so, these patches now use the recommended
  sequence.

  This doesn't affect 64-bit RISC-V systems, since the timer compare
  value fits inside a single register and can be updated with a single
  write.

   - Fix the RISC-V timer compare register update sequence on RV32
     systems to use the recommended sequence in the RISC-V ISA manual

     This avoids spurious interrupts during updates

   - Add a dependence on the new CONFIG_CACHEMAINT_FOR_DMA Kconfig
     symbol for Renesas and StarFive RISC-V SoCs

   - Add a temporary workaround for a Clang compiler bug caused by using
     asm_goto_output for get_user()

   - Clarify our documentation to specifically state a particular ISA
     specification version for a chapter number reference"

* tag 'riscv-for-linus-6.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: Add intermediate cast to 'unsigned long' in __get_user_asm
  riscv: Use 64-bit variable for output in __get_user_asm
  soc: renesas: Fix missing dependency on new CONFIG_CACHEMAINT_FOR_DMA
  riscv: ERRATA_STARFIVE_JH7100: Fix missing dependency on new CONFIG_CACHEMAINT_FOR_DMA
  riscv: suspend: Fix stimecmp update hazard on RV32
  riscv: kvm: Fix vstimecmp update hazard on RV32
  riscv: clocksource: Fix stimecmp update hazard on RV32
  Documentation: riscv: uabi: Clarify ISA spec version for canonical order
2026-01-24 18:55:48 -08:00
Linus Torvalds
2a4d91142e Merge tag 'platform-drivers-x86-v6.19-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86
Pull x86 platform driver fixes from Ilpo Järvinen:

 - acer-wmi:
     - Extend support for Acer Nitro AN515-58
     - Fix missing capability check

 - amd/wbrf: Fix memory leak in wbrf_record()

 - asus-armoury:
     - Fix GA403U* matching
     - Fix FA608UM TDP data
     - Add many models

 - asus-wmi: Move OOBE presence check outside deprecation ifdef

 - hp-bioscfg:
     - Fix kernel panic in GET_INSTANCE_ID macro
     - Fix kobject warnings for empty attribute names
     - Correct GUID to uppercase (lowercase letter prevented autoloading
       the module)

 - mellanox: Fix SN5640/SN5610 LED platform data

 - docs:
     - alienware-wmi: Typo fix
     - amd_hsmp: Fix document link

* tag 'platform-drivers-x86-v6.19-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: (21 commits)
  platform/x86: acer-wmi: Fix missing capability check
  platform/x86: acer-wmi: Extend support for Acer Nitro AN515-58
  platform/x86: asus-armoury: add support for GA403WW
  platform/x86: asus-armoury: keep the list ordered alphabetically
  platform/x86: asus-armoury: add support for G835L
  platform/x86: asus-armoury: fix ppt data for FA608UM
  platform/x86: hp-bioscfg: Fix automatic module loading
  platform/x86: hp-bioscfg: Fix kernel panic in GET_INSTANCE_ID macro
  platform/x86: hp-bioscfg: Fix kobject warnings for empty attribute names
  platform/x86: asus-wmi: fix sending OOBE at probe
  platform/x86: asus-armoury: add support for FA617XT
  platform/x86: asus-armoury: add support for FA401UV
  platform/x86: asus-armoury: add support for GV302XV
  platform/x86: asus-armoury: Add power limits for Asus G513QY
  platform/x86/amd: Fix memory leak in wbrf_record()
  platform/mellanox: Fix SN5640/SN5610 LED platform data
  docs: fix PPR for AMD EPYC broken link
  docs: alienware-wmi: fix typo
  platform/x86: asus-armoury: add support for GA403UV
  asus-armoury: fix ppt data for GA403U* renaming to GA403UI
  ...
2026-01-23 13:16:26 -08:00
Jani Nikula
a592a36e49 Documentation: use a source-read extension for the index link boilerplate
The root document usually has a special :ref:`genindex` link to the
generated index. This is also the case for Documentation/index.rst. The
other index.rst files deeper in the directory hierarchy usually don't.

For SPHINXDIRS builds, the root document isn't Documentation/index.rst,
but some other index.rst in the hierarchy. Currently they have a
".. only::" block to add the index link when doing SPHINXDIRS html
builds.

This is obviously very tedious and repetitive. The link is also added to
all index.rst files in the hierarchy for SPHINXDIRS builds, not just the
root document.

Put the boilerplate in a sphinx-includes/subproject-index.rst file, and
include it at the end of the root document for subproject builds in an
ad-hoc source-read extension defined in conf.py.

For now, keep having the boilerplate in translations, because this
approach currently doesn't cover translated index link headers.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
[jc: did s/doctree/kern_doc_dir/ ]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260123143149.2024303-1-jani.nikula@intel.com>
2026-01-23 11:59:34 -07:00
Lucas Wei
3fed7e0059 arm64: errata: Workaround for SI L1 downstream coherency issue
When software issues a Cache Maintenance Operation (CMO) targeting a
dirty cache line, the CPU and DSU cluster may optimize the operation by
combining the CopyBack Write and CMO into a single combined CopyBack
Write plus CMO transaction presented to the interconnect (MCN).
For these combined transactions, the MCN splits the operation into two
separate transactions, one Write and one CMO, and then propagates the
write and optionally the CMO to the downstream memory system or external
Point of Serialization (PoS).
However, the MCN may return an early CompCMO response to the DSU cluster
before the corresponding Write and CMO transactions have completed at
the external PoS or downstream memory. As a result, stale data may be
observed by external observers that are directly connected to the
external PoS or downstream memory.

This erratum affects any system topology in which the following
conditions apply:
 - The Point of Serialization (PoS) is located downstream of the
   interconnect.
 - A downstream observer accesses memory directly, bypassing the
   interconnect.

Conditions:
This erratum occurs only when all of the following conditions are met:
 1. Software executes a data cache maintenance operation, specifically,
    a clean or clean&invalidate by virtual address (DC CVAC or DC
    CIVAC), that hits on unique dirty data in the CPU or DSU cache.
    This results in a combined CopyBack and CMO being issued to the
    interconnect.
 2. The interconnect splits the combined transaction into separate Write
    and CMO transactions and returns an early completion response to the
    CPU or DSU before the write has completed at the downstream memory
    or PoS.
 3. A downstream observer accesses the affected memory address after the
    early completion response is issued but before the actual memory
    write has completed. This allows the observer to read stale data
    that has not yet been updated at the PoS or downstream memory.

The implementation of workaround put a second loop of CMOs at the same
virtual address whose operation meet erratum conditions to wait until
cache data be cleaned to PoC. This way of implementation mitigates
performance penalty compared to purely duplicate original CMO.

Signed-off-by: Lucas Wei <lucaswei@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
2026-01-23 13:30:38 +00:00
Yicong Yang
58ce78667a arm64: Add support for FEAT_{LS64, LS64_V}
Armv8.7 introduces single-copy atomic 64-byte loads and stores
instructions and its variants named under FEAT_{LS64, LS64_V}.
These features are identified by ID_AA64ISAR1_EL1.LS64 and the
use of such instructions in userspace (EL0) can be trapped.

As st64bv (FEAT_LS64_V) and st64bv0 (FEAT_LS64_ACCDATA) can not be tell
apart, FEAT_LS64 and FEAT_LS64_ACCDATA which will be supported in later
patch will be exported to userspace, FEAT_LS64_V will be enabled only
in kernel.

In order to support the use of corresponding instructions in userspace:
- Make ID_AA64ISAR1_EL1.LS64 visbile to userspace
- Add identifying and enabling in the cpufeature list
- Expose these support of these features to userspace through HWCAP3
  and cpuinfo

ld64b/st64b (FEAT_LS64) and st64bv (FEAT_LS64_V) is intended for
special memory (device memory) so requires support by the CPU, system
and target memory location (device that support these instructions).
The HWCAP3_LS64, implies the support of CPU and system (since no
identification method from system, so SoC vendors should advertise
support in the CPU if system also support them).

Otherwise for ld64b/st64b the atomicity may not be guaranteed or a
DABT will be generated, so users (probably userspace driver developer)
should make sure the target memory (device) also have the support.
For st64bv 0xffffffffffffffff will be returned as status result for
unsupported memory so user should check it.

Document the restrictions along with HWCAP3_LS64.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Oliver Upton <oupton@kernel.org>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Zhou Wang <wangzhou1@hisilicon.com>
Signed-off-by: Will Deacon <will@kernel.org>
2026-01-22 13:24:49 +00:00
Guodong Xu
69132c2d4c Documentation: riscv: uabi: Clarify ISA spec version for canonical order
Specify that chapter 27 refers to version 20191213 of the RISC-V ISA
Unprivileged Architecture. The chapter numbering differs across
specification versions - for example, in version 20250508, the ISA
Extension Naming Conventions is chapter 36, not chapter 27.

Historical versions of the RISC-V specification can be found via Link [1].

Acked-by: Paul Walmsley <pjw@kernel.org>
Link: https://riscv.org/specifications/ratified/ [1]
Fixes: f07b2b3f9d ("Documentation: riscv: add a section about ISA string ordering in /proc/cpuinfo")
Signed-off-by: Guodong Xu <guodong@riscstar.com>
Link: https://patch.msgid.link/20260115-adding-b-dtsi-v2-1-254dd61cf947@riscstar.com
2026-01-14 17:16:23 -07:00
Thomas Gleixner
2e4b28c48f treewide: Update email address
In a vain attempt to consolidate the email zoo switch everything to the
kernel.org account.

Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-01-11 06:09:11 -10:00
Akiyoshi Kurita
ae4f42ea4c docs: keystone: fix typo in knav-qmss documentation
Signed-off-by: Akiyoshi Kurita <weibu@redadmin.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251223112946.2580519-1-weibu@redadmin.org>
2026-01-06 15:03:19 -07:00
Haiyue Wang
c92724b40c docs: fix PPR for AMD EPYC broken link
As 'AMD Documentation Hub' [1] announced: "All technical documentation,
including for AMD EPYC™ processors ..., and more is now hosted on the
AMD Technical Information Portal (TIP) [2]".

By searching the No.55898, update the new URL.

[1] https://www.amd.com/en/search/documentation/hub.html
[2] https://docs.amd.com/

Signed-off-by: Haiyue Wang <haiyuewa@163.com>
Acked-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://patch.msgid.link/20251230133101.14362-1-haiyuewa@163.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2026-01-05 16:33:10 +02:00
Linus Torvalds
03de3e44a7 Merge tag 'riscv-for-linus-6.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Paul Walmsley:
 "Nothing exotic here; these are the cleanup and new ISA extension
  probing patches (not including CFI):

   - Add probing and userspace reporting support for the standard RISC-V
     ISA extensions Zilsd and Zclsd, which implement load/store dual
     instructions on RV32

   - Abstract the register saving code in setup_sigcontext() so it can
     be used for stateful RISC-V ISA extensions beyond the vector
     extension

   - Add the SBI extension ID and some initial data structure
     definitions for the RISC-V standard SBI debug trigger extension

   - Clean up some code slightly: change some page table functions to
     avoid atomic operations oinn !SMP and to avoid unnecessary casts to
     atomic_long_t; and use the existing RISCV_FULL_BARRIER macro in
     place of some open-coded 'fence rw,rw' instructions"

* tag 'riscv-for-linus-6.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: Add SBI debug trigger extension and function ids
  riscv/atomic.h: use RISCV_FULL_BARRIER in _arch_atomic* function.
  riscv: hwprobe: export Zilsd and Zclsd ISA extensions
  riscv: add ISA extension parsing for Zilsd and Zclsd
  dt-bindings: riscv: add Zilsd and Zclsd extension descriptions
  riscv: mm: use xchg() on non-atomic_long_t variables, not atomic_long_xchg()
  riscv: mm: ptep_get_and_clear(): avoid atomic ops when !CONFIG_SMP
  riscv: mm: pmdp_huge_get_and_clear(): avoid atomic ops when !CONFIG_SMP
  riscv: signal: abstract header saving for setup_sigcontext
2025-12-28 09:44:26 -08:00
Shubham Sharma
1de54df949 Documentation: arm: keystone: update DT binding reference
Update the device tree binding reference from .txt to YAML.
Binding was converted in commit 20b3c9a403 ("dt-bindings: arm: Convert ti,keystone to DT schema")
and moved to Documentation/devicetree/bindings/arm/ti/ti,keystone.yaml.

Signed-off-by: Shubham Sharma <slopixelz@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251207195632.68681-1-slopixelz@gmail.com>
2025-12-22 15:20:05 -07:00
Pincheng Wang
6118ebed3b riscv: hwprobe: export Zilsd and Zclsd ISA extensions
Export Zilsd and Zclsd ISA extensions through hwprobe.

Signed-off-by: Pincheng Wang <pincheng.plct@isrc.iscas.ac.cn>
Reviewed-by: Nutty Liu <nutty.liu@hotmail.com>
Link: https://patch.msgid.link/20250826162939.1494021-4-pincheng.plct@isrc.iscas.ac.cn
[pjw@kernel.org: fixed whitespace; updated to apply]
Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-12-19 00:22:30 -07:00
Ingo Molnar
ac87efcf9e x86/boot/Documentation: Fix whitespace noise in boot.rst
There's a lot of unnecessary whitespace damage in this
file: space before tabs, etc., that has no formatting
or readability effect or advantages.

Fix them.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://patch.msgid.link/176535283007.498.16442167388418039352.tip-bot2@tip-bot2
2025-12-12 09:38:14 +01:00
Swaraj Gaikwad
5288176a54 x86/boot/Documentation: Fix htmldocs build warning due to malformed table in boot.rst
Sphinx reports htmldocs warnings:

  Documentation/arch/x86/boot.rst:437: ERROR: Malformed table.
  Text in column margin in table line 2.

The table header defined the first column width as 2 characters ("=="),
which is too narrow for entries like "0x10" and "0x13". This caused the
text to spill into the margin, triggering a docutils parsing failure.

Fix it by extending the first column of assigned boot loader ID to 4
characters ("====") to fit the widest entries.

Fixes: 1c3377bee2 ("x86/boot/Documentation: Prefix hexadecimal literals with 0x")
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Swaraj Gaikwad <swarajgaikwad1925@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://patch.msgid.link/20251210092814.9986-1-swarajgaikwad1925@gmail.com
2025-12-10 08:34:38 +01:00
Linus Torvalds
cc3ee4ba57 Merge tag 'x86-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Miscellaneous documentation fixes"

* tag 'x86-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/Documentation: Prefix hexadecimal literals with 0x
  x86/boot/Documentation: Spell 'ID' consistently
  x86/platform: Fix and extend kernel-doc comments in <asm/x86_init.h>
2025-12-06 12:33:26 -08:00
Linus Torvalds
07025b51c1 Merge tag 'riscv-for-linus-6.19-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Paul Walmsley:

 - Enable parallel hotplug for RISC-V

 - Optimize vector regset allocation for ptrace()

 - Add a kernel selftest for the vector ptrace interface

 - Enable the userspace RAID6 test to build and run using RISC-V vectors

 - Add initial support for the Zalasr RISC-V ratified ISA extension

 - For the Zicbop RISC-V ratified ISA extension to userspace, expose
   hardware and kernel support to userspace and add a kselftest for
   Zicbop

 - Convert open-coded instances of 'asm goto's that are controlled by
   runtime ALTERNATIVEs to use riscv_has_extension_{un,}likely(),
   following arm64's alternative_has_cap_{un,}likely()

 - Remove an unnecessary mask in the GFP flags used in some calls to
   pagetable_alloc()

* tag 'riscv-for-linus-6.19-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  selftests/riscv: Add Zicbop prefetch test
  riscv: hwprobe: Expose Zicbop extension and its block size
  riscv: Introduce Zalasr instructions
  riscv: hwprobe: Export Zalasr extension
  dt-bindings: riscv: Add Zalasr ISA extension description
  riscv: Add ISA extension parsing for Zalasr
  selftests: riscv: Add test for the Vector ptrace interface
  riscv: ptrace: Optimize the allocation of vector regset
  raid6: test: Add support for RISC-V
  raid6: riscv: Allow code to be compiled in userspace
  raid6: riscv: Prevent compiler from breaking inline vector assembly code
  riscv: cmpxchg: Use riscv_has_extension_likely
  riscv: bitops: Use riscv_has_extension_likely
  riscv: hweight: Use riscv_has_extension_likely
  riscv: checksum: Use riscv_has_extension_likely
  riscv: pgtable: Use riscv_has_extension_unlikely
  riscv: Remove __GFP_HIGHMEM masking
  RISC-V: Enable HOTPLUG_PARALLEL for secondary CPUs
2025-12-05 16:26:57 -08:00
Linus Torvalds
f96163865a Merge tag 'docs-6.19' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
 "This has been another busy cycle for documentation, with a lot of
  build-system thrashing. That work should slow down from here on out.

   - The various scripts and tools for documentation were spread out in
     several directories; now they are (almost) all coalesced under
     tools/docs/. The holdout is the kernel-doc script, which cannot be
     easily moved without some further thought.

   - As the amount of Python code increases, we are accumulating modules
     that are imported by multiple programs. These modules have been
     pulled together under tools/lib/python/ -- at least, for
     documentation-related programs. There is other Python code in the
     tree that might eventually want to move toward this organization.

   - The Perl kernel-doc.pl script has been removed. It is no longer
     used by default, and nobody has missed it, least of all anybody who
     actually had to look at it.

   - The docs build was controlled by a complex mess of makefilese that
     few dared to touch. Mauro has moved that logic into a new program
     (tools/docs/sphinx-build-wrapper) that, with any luck at all, will
     be far easier to understand and maintain.

   - The get_feat.pl program, used to access information under
     Documentation/features/, has been rewritten in Python, bringing an
     end to the use of Perl in the docs subsystem.

   - The top-level README file has been reorganized into a more
     reader-friendly presentation.

   - A lot of Chinese translation additions

   - Typo fixes and documentation updates as usual"

* tag 'docs-6.19' of git://git.lwn.net/linux: (164 commits)
  docs: makefile: move rustdoc check to the build wrapper
  README: restructure with role-based documentation and guidelines
  docs: kdoc: various fixes for grammar, spelling, punctuation
  docs: kdoc_parser: use '@' for Excess enum value
  docs: submitting-patches: Clarify that removal of Acks needs explanation too
  docs: kdoc_parser: add data/function attributes to ignore
  docs: MAINTAINERS: update Mauro's files/paths
  docs/zh_CN: Add wd719x.rst translation
  docs/zh_CN: Add libsas.rst translation
  get_feat.pl: remove it, as it got replaced by get_feat.py
  Documentation/sphinx/kernel_feat.py: use class directly
  tools/docs/get_feat.py: convert get_feat.pl to Python
  Documentation/admin-guide: fix typo and comment in cscope example
  docs/zh_CN: Add data-integrity.rst translation
  docs/zh_CN: Add blk-mq.rst translation
  docs/zh_CN: Add block/index.rst translation
  docs/zh_CN: Update the Chinese translation of kbuild.rst
  docs: bring some order to our Python module hierarchy
  docs: Move the python libraries to tools/lib/python
  Documentation/kernel-parameters: Move the kernel build options
  ...
2025-12-03 11:34:28 -08:00
Ingo Molnar
1c3377bee2 x86/boot/Documentation: Prefix hexadecimal literals with 0x
The x86 bootloader ID specification text uses hexadecimal
values without a 0x prefix:

        D  kexec-tools
        E  Extended (see ext_loader_type)
        F  Special (0xFF = undefined)
        10 Reserved
        11 Minimal Linux Bootloader
           <http://sebastian-plotz.blogspot.de>
        12 OVMF UEFI virtualization stack
        13 barebox

Which beyond the ambiguity of '13' in isolation, also
made me fail a grep -wi '0xd' when I was looking for
the kexec bootloader ID definition and caused quite
a bit of head-scratching before I found out why it
didn't show up.

Furthermore, the actual explanatory text uses the 0x
prefix:

  For boot loader IDs above T = 0xD, write T = 0xE to this field and
  write the extended ID minus 0x10 to the ext_loader_type field.
  Similarly, the ext_loader_ver field can be used to provide more than
  four bits for the bootloader version.

So make it all both unambiguous, easy to grep and consistent
across the entire documentation by prefixing the IDs with 0x.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-kernel@vger.kernel.org
2025-12-03 18:49:09 +01:00
Ingo Molnar
c7957da777 x86/boot/Documentation: Spell 'ID' consistently
The bootloader ID specification text uses 2 capitalization
variants for the same thing: 'id', 'ids', 'ID' and 'IDs'.

Use 'ID/IDs' consistently.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-kernel@vger.kernel.org
2025-12-03 18:49:00 +01:00
Linus Torvalds
44fc84337b Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas:
 "These are the arm64 updates for 6.19.

  The biggest part is the Arm MPAM driver under drivers/resctrl/.
  There's a patch touching mm/ to handle spurious faults for huge pmd
  (similar to the pte version). The corresponding arm64 part allows us
  to avoid the TLB maintenance if a (huge) page is reused after a write
  fault. There's EFI refactoring to allow runtime services with
  preemption enabled and the rest is the usual perf/PMU updates and
  several cleanups/typos.

  Summary:

  Core features:

   - Basic Arm MPAM (Memory system resource Partitioning And Monitoring)
     driver under drivers/resctrl/ which makes use of the fs/rectrl/ API

  Perf and PMU:

   - Avoid cycle counter on multi-threaded CPUs

   - Extend CSPMU device probing and add additional filtering support
     for NVIDIA implementations

   - Add support for the PMUs on the NoC S3 interconnect

   - Add additional compatible strings for new Cortex and C1 CPUs

   - Add support for data source filtering to the SPE driver

   - Add support for i.MX8QM and "DB" PMU in the imx PMU driver

  Memory managemennt:

   - Avoid broadcast TLBI if page reused in write fault

   - Elide TLB invalidation if the old PTE was not valid

   - Drop redundant cpu_set_*_tcr_t0sz() macros

   - Propagate pgtable_alloc() errors outside of __create_pgd_mapping()

   - Propagate return value from __change_memory_common()

  ACPI and EFI:

   - Call EFI runtime services without disabling preemption

   - Remove unused ACPI function

  Miscellaneous:

   - ptrace support to disable streaming on SME-only systems

   - Improve sysreg generation to include a 'Prefix' descriptor

   - Replace __ASSEMBLY__ with __ASSEMBLER__

   - Align register dumps in the kselftest zt-test

   - Remove some no longer used macros/functions

   - Various spelling corrections"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (94 commits)
  arm64/mm: Document why linear map split failure upon vm_reset_perms is not problematic
  arm64/pageattr: Propagate return value from __change_memory_common
  arm64/sysreg: Remove unused define ARM64_FEATURE_FIELD_BITS
  KVM: arm64: selftests: Consider all 7 possible levels of cache
  KVM: arm64: selftests: Remove ARM64_FEATURE_FIELD_BITS and its last user
  arm64: atomics: lse: Remove unused parameters from ATOMIC_FETCH_OP_AND macros
  Documentation/arm64: Fix the typo of register names
  ACPI: GTDT: Get rid of acpi_arch_timer_mem_init()
  perf: arm_spe: Add support for filtering on data source
  perf: Add perf_event_attr::config4
  perf/imx_ddr: Add support for PMU in DB (system interconnects)
  perf/imx_ddr: Get and enable optional clks
  perf/imx_ddr: Move ida_alloc() from ddr_perf_init() to ddr_perf_probe()
  dt-bindings: perf: fsl-imx-ddr: Add compatible string for i.MX8QM, i.MX8QXP and i.MX8DXL
  arm64: remove duplicate ARCH_HAS_MEM_ENCRYPT
  arm64: mm: use untagged address to calculate page index
  MAINTAINERS: new entry for MPAM Driver
  arm_mpam: Add kunit tests for props_mismatch()
  arm_mpam: Add kunit test for bitmap reset
  arm_mpam: Add helper to reset saved mbwu state
  ...
2025-12-02 17:03:55 -08:00
Catalin Marinas
17c05cb0ef Merge branches 'for-next/misc', 'for-next/kselftest', 'for-next/efi-preempt', 'for-next/assembler-macro', 'for-next/typos', 'for-next/sme-ptrace-disable', 'for-next/local-tlbi-page-reused', 'for-next/mpam', 'for-next/acpi' and 'for-next/documentation', remote-tracking branch 'arm64/for-next/perf' into for-next/core
* arm64/for-next/perf:
  perf: arm_spe: Add support for filtering on data source
  perf: Add perf_event_attr::config4
  perf/imx_ddr: Add support for PMU in DB (system interconnects)
  perf/imx_ddr: Get and enable optional clks
  perf/imx_ddr: Move ida_alloc() from ddr_perf_init() to ddr_perf_probe()
  dt-bindings: perf: fsl-imx-ddr: Add compatible string for i.MX8QM, i.MX8QXP and i.MX8DXL
  arch_topology: Provide a stub topology_core_has_smt() for !CONFIG_GENERIC_ARCH_TOPOLOGY
  perf/arm-ni: Fix and optimise register offset calculation
  perf: arm_pmuv3: Add new Cortex and C1 CPU PMUs
  perf: arm_cspmu: fix error handling in arm_cspmu_impl_unregister()
  perf/arm-ni: Add NoC S3 support
  perf/arm_cspmu: nvidia: Add pmevfiltr2 support
  perf/arm_cspmu: nvidia: Add revision id matching
  perf/arm_cspmu: Add pmpidr support
  perf/arm_cspmu: Add callback to reset filter config
  perf: arm_pmuv3: Don't use PMCCNTR_EL0 on SMT cores

* for-next/misc:
  : Miscellaneous patches
  arm64: atomics: lse: Remove unused parameters from ATOMIC_FETCH_OP_AND macros
  arm64: remove duplicate ARCH_HAS_MEM_ENCRYPT
  arm64: mm: use untagged address to calculate page index
  arm64: mm: make linear mapping permission update more robust for patial range
  arm64/mm: Elide TLB flush in certain pte protection transitions
  arm64/mm: Rename try_pgd_pgtable_alloc_init_mm
  arm64/mm: Allow __create_pgd_mapping() to propagate pgtable_alloc() errors
  arm64: add unlikely hint to MTE async fault check in el0_svc_common
  arm64: acpi: add newline to deferred APEI warning
  arm64: entry: Clean out some indirection
  arm64/mm: Ensure PGD_SIZE is aligned to 64 bytes when PA_BITS = 52
  arm64/mm: Drop cpu_set_[default|idmap]_tcr_t0sz()
  arm64: remove unused ARCH_PFN_OFFSET
  arm64: use SOFTIRQ_ON_OWN_STACK for enabling softirq stack
  arm64: Remove assertion on CONFIG_VMAP_STACK

* for-next/kselftest:
  : arm64 kselftest patches
  kselftest/arm64: Align zt-test register dumps

* for-next/efi-preempt:
  : arm64: Make EFI calls preemptible
  arm64/efi: Call EFI runtime services without disabling preemption
  arm64/efi: Move uaccess en/disable out of efi_set_pgd()
  arm64/efi: Drop efi_rt_lock spinlock from EFI arch wrapper
  arm64/fpsimd: Permit kernel mode NEON with IRQs off
  arm64/fpsimd: Don't warn when EFI execution context is preemptible
  efi/runtime-wrappers: Keep track of the efi_runtime_lock owner
  efi: Add missing static initializer for efi_mm::cpus_allowed_lock

* for-next/assembler-macro:
  : arm64: Replace __ASSEMBLY__ with __ASSEMBLER__ in headers
  arm64: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers
  arm64: Replace __ASSEMBLY__ with __ASSEMBLER__ in uapi headers

* for-next/typos:
  : Random typo/spelling fixes
  arm64: Fix double word in comments
  arm64: Fix typos and spelling errors in comments

* for-next/sme-ptrace-disable:
  : Support disabling streaming mode via ptrace on SME only systems
  kselftest/arm64: Cover disabling streaming mode without SVE in fp-ptrace
  kselftst/arm64: Test NT_ARM_SVE FPSIMD format writes on non-SVE systems
  arm64/sme: Support disabling streaming mode via ptrace on SME only systems

* for-next/local-tlbi-page-reused:
  : arm64, mm: avoid TLBI broadcast if page reused in write fault
  arm64, tlbflush: don't TLBI broadcast if page reused in write fault
  mm: add spurious fault fixing support for huge pmd

* for-next/mpam: (34 commits)
  : Basic Arm MPAM driver (more to follow)
  MAINTAINERS: new entry for MPAM Driver
  arm_mpam: Add kunit tests for props_mismatch()
  arm_mpam: Add kunit test for bitmap reset
  arm_mpam: Add helper to reset saved mbwu state
  arm_mpam: Use long MBWU counters if supported
  arm_mpam: Probe for long/lwd mbwu counters
  arm_mpam: Consider overflow in bandwidth counter state
  arm_mpam: Track bandwidth counter state for power management
  arm_mpam: Add mpam_msmon_read() to read monitor value
  arm_mpam: Add helpers to allocate monitors
  arm_mpam: Probe and reset the rest of the features
  arm_mpam: Allow configuration to be applied and restored during cpu online
  arm_mpam: Use a static key to indicate when mpam is enabled
  arm_mpam: Register and enable IRQs
  arm_mpam: Extend reset logic to allow devices to be reset any time
  arm_mpam: Add a helper to touch an MSC from any CPU
  arm_mpam: Reset MSC controls from cpuhp callbacks
  arm_mpam: Merge supported features during mpam_enable() into mpam_class
  arm_mpam: Probe the hardware features resctrl supports
  arm_mpam: Add helpers for managing the locking around the mon_sel registers
  ...

* for-next/acpi:
  : arm64 acpi updates
  ACPI: GTDT: Get rid of acpi_arch_timer_mem_init()

* for-next/documentation:
  : arm64 Documentation updates
  Documentation/arm64: Fix the typo of register names
2025-11-28 15:47:12 +00:00
Zenon Xiu
4b7a59fa70 Documentation/arm64: Fix the typo of register names
The register name 'HWFGWTR_EL2' and 'HWFGRTR_EL2' is wrong, should be 'HFGWTR_EL2' and 'HFGRTR_EL2'.
Find the register description on arm website here,
https://developer.arm.com/documentation/ddi0601/2025-09/AArch64-Registers/HFGWTR-EL2--Hypervisor-Fine-Grained-Write-Trap-Register
https://developer.arm.com/documentation/ddi0601/2025-09/AArch64-Registers/HFGRTR-EL2--Hypervisor-Fine-Grained-Read-Trap-Register?lang=en

Signed-off-by: Zenon Xiu <zenonxiu@outlook.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-11-25 12:26:31 +00:00
Yao Zihong
e0a504984a riscv: hwprobe: Expose Zicbop extension and its block size
- Add `RISCV_HWPROBE_EXT_ZICBOP` to report the presence of the
  Zicbop extension.
- Add `RISCV_HWPROBE_KEY_ZICBOP_BLOCK_SIZE` to expose the block
  size (in bytes) when Zicbop is supported.
- Update hwprobe.rst to document the new extension bit and block
  size key, following the existing Zicbom/Zicboz style.

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Yao Zihong <zihong.plct@isrc.iscas.ac.cn>
Link: https://patch.msgid.link/20251118162436.15485-2-zihong.plct@isrc.iscas.ac.cn
[pjw@kernel.org: updated to apply]
Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-11-19 09:19:29 -07:00
Xu Lu
f4922b6916 riscv: hwprobe: Export Zalasr extension
Export the Zalasr extension to userspace using hwprobe.

Signed-off-by: Xu Lu <luxu.kernel@bytedance.com>
Link: https://patch.msgid.link/20251020042056.30283-4-luxu.kernel@bytedance.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-11-19 09:19:28 -07:00
Mark Brown
472800cd5e arm64/sme: Support disabling streaming mode via ptrace on SME only systems
Currently it is not possible to disable streaming mode via ptrace on SME
only systems, the interface for doing this is to write via NT_ARM_SVE but
such writes will be rejected on a system without SVE support. Enable this
functionality by allowing userspace to write SVE_PT_REGS_FPSIMD format data
via NT_ARM_SVE with the vector length set to 0 on SME only systems. Such
writes currently error since we require that a vector length is specified
which should minimise the risk that existing software is relying on current
behaviour.

Reads are not supported since I am not aware of any use case for this and
there is some risk that an existing userspace application may be confused if
it reads NT_ARM_SVE on a system without SVE. Existing kernels will return
FPSIMD formatted register state from NT_ARM_SVE if full SVE state is not
stored, for example if the task has not used SVE. Returning a vector length
of 0 would create a risk that software would try to do things like allocate
space for register state with zero sizes, while returning a vector length of
128 bits would look like SVE is supported. It seems safer to just not make
the changes to add read support.

It remains possible for userspace to detect a SME only system via the ptrace
interface only since reads of NT_ARM_SSVE and NT_ARM_ZA will succeed while
reads of NT_ARM_SVE will fail. Read/write access to the FPSIMD registers in
non-streaming mode is available via REGSET_FPR.

sve_set_common() already avoids allocating SVE storage when doing a FPSIMD
formatted write and allocating SME storage when doing a NT_ARM_SVE write so
we change the function to validate the new case and skip setting a vector
length for it.

The aim is to make a minimally invasive change, no operation that would
previously have succeeded will be affected, and we use a previously
defined interface in new circumstances rather than define completely new
ABI.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: David Spickett <david.spickett@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-11-17 20:11:54 +00:00
Peter Oberparleiter
2a2153a2ba s390/debug: Update description of resize operation
With commit 1204777867 ("s390/debug: keep debug data on resize")
the behavior of a debug area resize operation was changed. Update the
associated documentation to reflect this change.

Fixes: 1204777867 ("s390/debug: keep debug data on resize")
Reported-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-11-17 11:55:16 +01:00
Hugo Osvaldo Barrera
8e3b02d260 Documentation/x86: explain LINUX_EFI_INITRD_MEDIA_GUID
Since the Handover Protocol was deprecated, the recommended approach is
to provide an initrd using a UEFI boot service with the
LINUX_EFI_INITRD_MEDIA_GUID device path. Documentation for the new
approach has been no more than an admonition with a link to an existing
implementation.

Provide a short explanation of this functionality, to ease future
implementations without having to reverse engineer existing ones.

[Bagas: Don't use :ref: link to EFI stub documentation and refer to
OVMF/edk2 implementation]

Signed-off-by: Hugo Osvaldo Barrera <hugo@whynothugo.nl>
Link: https://lore.kernel.org/r/20250428131206.8656-2-hugo@whynothugo.nl
Co-developed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251013085718.27085-1-bagasdotme@gmail.com>
2025-10-14 07:53:40 -06:00
Linus Torvalds
50ac57c3b1 Merge tag 'x86_tdx_for_6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 TDX updates from Dave Hansen:
 "The biggest change here is making TDX and kexec play nicely together.

  Before this, the memory encryption hardware (which doesn't respect
  cache coherency) could write back old cachelines on top of data in the
  new kernel, so kexec and TDX were made mutually exclusive. This
  removes the limitation.

  There is also some work to tighten up a hardware bug workaround and
  some MAINTAINERS updates.

   - Make TDX and kexec work together

    - Skip TDX bug workaround when the bug is not present

    - Update maintainers entries"

* tag 'x86_tdx_for_6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/virt/tdx: Use precalculated TDVPR page physical address
  KVM/TDX: Explicitly do WBINVD when no more TDX SEAMCALLs
  x86/virt/tdx: Update the kexec section in the TDX documentation
  x86/virt/tdx: Remove the !KEXEC_CORE dependency
  x86/kexec: Disable kexec/kdump on platforms with TDX partial write erratum
  x86/virt/tdx: Mark memory cache state incoherent when making SEAMCALL
  x86/sme: Use percpu boolean to control WBINVD during kexec
  x86/kexec: Consolidate relocate_kernel() function parameters
  x86/tdx: Skip clearing reclaimed pages unless X86_BUG_TDX_PW_MCE is present
  x86/tdx: Tidy reset_pamt functions
  x86/tdx: Eliminate duplicate code in tdx_clear_page()
  MAINTAINERS: Add KVM mail list to the TDX entry
  MAINTAINERS: Add Rick Edgecombe as a TDX reviewer
  MAINTAINERS: Update the file list in the TDX entry.
2025-10-04 10:01:30 -07:00
Linus Torvalds
ee2fe81cdc Merge tag 'docs-6.18' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
 "It has been a relatively busy cycle in docsland, with changes all
  over:

   - Bring the kernel memory-model docs into the Sphinx build in the
     "literal include" mode.

   - Lots of build-infrastructure work, further cleaning up long-term
     kernel-doc technical debt. The sphinx-pre-install tool has been
     converted to Python and updated for current systems.

   - A new tool to detect when documents have been moved and generate
     HTML redirects; this can be used on kernel.org (or any other site
     hosting the rendered docs) to avoid breaking links.

   - Automated processing of the YAML files describing the netlink
     protocol.

   - A significant update of the maintainer's PGP guide.

  ... and a seemingly endless series of typo fixes, build-problem fixes,
  etc"

* tag 'docs-6.18' of git://git.lwn.net/linux: (193 commits)
  Documentation/features: Update feature lists for 6.17-rc7
  docs: remove cdomain.py
  Documentation/process: submitting-patches: fix typo in "were do"
  docs: dev-tools/lkmm: Fix typo of missing file extension
  Documentation: trace: histogram: Convert ftrace docs cross-reference
  Documentation: trace: histogram-design: Wrap introductory note in note:: directive
  Documentation: trace: historgram-design: Separate sched_waking histogram section heading and the following diagram
  Documentation: trace: histogram-design: Trim trailing vertices in diagram explanation text
  Documentation: trace: histogram: Fix histogram trigger subsection number order
  docs: driver-api: fix spelling of "buses".
  Documentation: fbcon: Use admonition directives
  Documentation: fbcon: Reindent 8th step of attach/detach/unload
  Documentation: fbcon: Add boot options and attach/detach/unload section headings
  docs: filesystems: sysfs: add remaining top level sysfs directory descriptions
  docs: filesystems: sysfs: clarify symlink destinations in dev and bus/devices descriptions
  docs: filesystems: sysfs: remove top level sysfs net directory
  docs: maintainer: Fix ambiguous subheading formatting
  docs: kdoc: a few more dump_typedef() tweaks
  docs: kdoc: remove redundant comment stripping in dump_typedef()
  docs: kdoc: remove some dead code in dump_typedef()
  ...
2025-10-03 17:16:13 -07:00
Linus Torvalds
a65879b458 Merge tag 'x86_cpu_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cpuid updates from Borislav Petkov:

 - Make UMIP instruction detection more robust

 - Correct and cleanup AMD CPU topology detection; document the relevant
   CPUID leaves topology parsing precedence on AMD

 - Add support for running the kernel as guest on FreeBSD's Bhyve
   hypervisor

 - Cleanups and improvements

* tag 'x86_cpu_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/umip: Fix decoding of register forms of 0F 01 (SGDT and SIDT aliases)
  x86/umip: Check that the instruction opcode is at least two bytes
  Documentation/x86/topology: Detail CPUID leaves used for topology enumeration
  x86/cpu/topology: Define AMD64_CPUID_EXT_FEAT MSR
  x86/cpu/topology: Check for X86_FEATURE_XTOPOLOGY instead of passing has_xtopology
  x86/cpu/cacheinfo: Simplify cacheinfo_amd_init_llc_id() using _cpuid4_info
  x86/cpu: Rename and move CPU model entry for Diamond Rapids
  x86/cpu: Detect FreeBSD Bhyve hypervisor
2025-09-30 13:19:08 -07:00
Linus Torvalds
417552999d Merge tag 'powerpc-6.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Madhavan Srinivasan:

 - powerpc support for BPF arena and arena atomics

 - Patches to switch to msi parent domain (per-device MSI domains)

 - Add a lock contention tracepoint in the queued spinlock slowpath

 - Fixes for underflow in pseries/powernv msi and pci paths

 - Switch from legacy-of-mm-gpiochip dependency to platform driver

 - Fixes for handling TLB misses

 - Introduce support for powerpc papr-hvpipe

 - Add vpa-dtl PMU driver for pseries platform

 - Misc fixes and cleanups

Thanks to Aboorva Devarajan, Aditya Bodkhe, Andrew Donnellan, Athira
Rajeev, Cédric Le Goater, Christophe Leroy, Erhard Furtner, Gautam
Menghani, Geert Uytterhoeven, Haren Myneni, Hari Bathini, Joe Lawrence,
Kajol Jain, Kienan Stewart, Linus Walleij, Mahesh Salgaonkar, Nam Cao,
Nicolas Schier, Nysal Jan K.A., Ritesh Harjani (IBM), Ruben Wauters,
Saket Kumar Bhaskar, Shashank MS, Shrikanth Hegde, Tejas Manhas, Thomas
Gleixner, Thomas Huth, Thorsten Blum, Tyrel Datwyler, and Venkat Rao
Bagalkote.

* tag 'powerpc-6.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (49 commits)
  powerpc/pseries: Define __u{8,32} types in papr_hvpipe_hdr struct
  genirq/msi: Remove msi_post_free()
  powerpc/perf/vpa-dtl: Add documentation for VPA dispatch trace log PMU
  powerpc/perf/vpa-dtl: Handle the writing of perf record when aux wake up is needed
  powerpc/perf/vpa-dtl: Add support to capture DTL data in aux buffer
  powerpc/perf/vpa-dtl: Add support to setup and free aux buffer for capturing DTL data
  docs: ABI: sysfs-bus-event_source-devices-vpa-dtl: Document sysfs event format entries for vpa_dtl pmu
  powerpc/vpa_dtl: Add interface to expose vpa dtl counters via perf
  powerpc/time: Expose boot_tb via accessor
  powerpc/32: Remove PAGE_KERNEL_TEXT to fix startup failure
  powerpc/fprobe: fix updated fprobe for function-graph tracer
  powerpc/ftrace: support CONFIG_FUNCTION_GRAPH_RETVAL
  powerpc64/modules: replace stub allocation sentinel with an explicit counter
  powerpc64/modules: correctly iterate over stubs in setup_ftrace_ool_stubs
  powerpc/ftrace: ensure ftrace record ops are always set for NOPs
  powerpc/603: Really copy kernel PGD entries into all PGDIRs
  powerpc/8xx: Remove left-over instruction and comments in DataStoreTLBMiss handler
  powerpc/pseries: HVPIPE changes to support migration
  powerpc/pseries: Enable hvpipe with ibm,set-system-parameter RTAS
  powerpc/pseries: Enable HVPIPE event message interrupt
  ...
2025-09-29 19:28:50 -07:00
Linus Torvalds
cb7e3669c6 Merge tag 'riscv-for-linus-6.18-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Paul Walmsley

 - Replacement of __ASSEMBLY__ with __ASSEMBLER__ in header files (other
   architectures have already merged this type of cleanup)

 - The introduction of ioremap_wc() for RISC-V

 - Cleanup of the RISC-V kprobes code to use mostly-extant macros rather
   than open code

 - A RISC-V kprobes unit test

 - An architecture-specific endianness swap macro set implementation,
   leveraging some dedicated RISC-V instructions for this purpose if
   they are available

 - The ability to identity and communicate to userspace the presence
   of a MIPS P8700-specific ISA extension, and to leverage its
   MIPS-specific PAUSE implementation in cpu_relax()

 - Several other miscellaneous cleanups

* tag 'riscv-for-linus-6.18-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (39 commits)
  riscv: errata: Fix the PAUSE Opcode for MIPS P8700
  riscv: hwprobe: Document MIPS xmipsexectl vendor extension
  riscv: hwprobe: Add MIPS vendor extension probing
  riscv: Add xmipsexectl instructions
  riscv: Add xmipsexectl as a vendor extension
  dt-bindings: riscv: Add xmipsexectl ISA extension description
  riscv: cpufeature: add validation for zfa, zfh and zfhmin
  perf: riscv: skip empty batches in counter start
  selftests: riscv: Add README for RISC-V KSelfTest
  riscv: sbi: Switch to new sys-off handler API
  riscv: Move vendor errata definitions to new header
  RISC-V: ACPI: enable parsing the BGRT table
  riscv: Enable ARCH_HAVE_NMI_SAFE_CMPXCHG
  riscv: pi: use 'targets' instead of extra-y in Makefile
  riscv: introduce asm/swab.h
  riscv: mmap(): use unsigned offset type in riscv_sys_mmap
  drivers/perf: riscv: Remove redundant ternary operators
  riscv: mm: Use mmu-type from FDT to limit SATP mode
  riscv: mm: Return intended SATP mode for noXlvl options
  riscv: kprobes: Remove duplication of RV_EXTRACT_ITYPE_IMM
  ...
2025-09-29 19:01:08 -07:00
Will Deacon
f2d64a22fa Merge branch 'for-next/perf' into for-next/core
* for-next/perf: (29 commits)
  perf/dwc_pcie: Fix use of uninitialized variable
  Documentation: hisi-pmu: Add introduction to HiSilicon V3 PMU
  Documentation: hisi-pmu: Fix of minor format error
  drivers/perf: hisi: Add support for L3C PMU v3
  drivers/perf: hisi: Refactor the event configuration of L3C PMU
  drivers/perf: hisi: Extend the field of tt_core
  drivers/perf: hisi: Extract the event filter check of L3C PMU
  drivers/perf: hisi: Simplify the probe process of each L3C PMU version
  drivers/perf: hisi: Export hisi_uncore_pmu_isr()
  drivers/perf: hisi: Relax the event ID check in the framework
  perf: Fujitsu: Add the Uncore PMU driver
  perf/arm-cmn: Fix CMN S3 DTM offset
  perf: arm_spe: Prevent overflow in PERF_IDX2OFF()
  coresight: trbe: Prevent overflow in PERF_IDX2OFF()
  MAINTAINERS: Remove myself from HiSilicon PMU maintainers
  drivers/perf: hisi: Add support for HiSilicon MN PMU driver
  drivers/perf: hisi: Add support for HiSilicon NoC PMU
  perf: arm_pmuv3: Factor out PMCCNTR_EL0 use conditions
  arm64/boot: Enable EL2 requirements for SPE_FEAT_FDS
  arm64/boot: Factor out a macro to check SPE version
  ...
2025-09-24 16:34:52 +01:00
Will Deacon
e0669b95f7 Merge branch 'for-next/docs' into for-next/core
* for-next/docs:
  arm64/sme: Drop inaccurate documentation of streaming mode switches
2025-09-24 16:33:58 +01:00
Mark Rutland
0c33aa1804 arm64: errata: Apply workarounds for Neoverse-V3AE
Neoverse-V3AE is also affected by erratum #3312417, as described in its
Software Developer Errata Notice (SDEN) document:

  Neoverse V3AE (MP172) SDEN v9.0, erratum 3312417
  https://developer.arm.com/documentation/SDEN-2615521/9-0/

Enable the workaround for Neoverse-V3AE, and document this.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2025-09-22 11:27:14 +01:00
Athira Rajeev
4a774b39e6 powerpc/perf/vpa-dtl: Add documentation for VPA dispatch trace log PMU
Documentation for vpa-dtl (Virtual Processor Area - Dispatch Trace Log)
PMU interface. And how it can be used to collect the distrace trace log
entries in perf data, how to process/report as part of perf report/perf
script.

Signed-off-by: Athira Rajeev <atrajeev@linux.ibm.com>
Tested-by: Tejas Manhas <tejas05@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250915102947.26681-8-atrajeev@linux.ibm.com
2025-09-22 14:48:57 +05:30
Aleksa Paunovic
c9a9fc2322 riscv: hwprobe: Document MIPS xmipsexectl vendor extension
Document support for MIPS vendor extensions using the key
"RISCV_HWPROBE_KEY_VENDOR_EXT_MIPS_0" and xmipsexectl vendor extension
using the key "RISCV_HWPROBE_VENDOR_EXT_XMIPSEXECTL".

Signed-off-by: Aleksa Paunovic <aleksa.paunovic@htecgroup.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20250724-p8700-pause-v5-5-a6cbbe1c3412@htecgroup.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-09-19 10:33:56 -06:00
James Clark
00d7a1af5a arm64/boot: Enable EL2 requirements for SPE_FEAT_FDS
SPE data source filtering (optional from Armv8.8) requires that traps to
the filter register PMSDSFR be disabled. Document the requirements and
disable the traps if the feature is present.

Tested-by: Leo Yan <leo.yan@arm.com>
Reviewed-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
2025-09-18 14:17:02 +01:00
K Prateek Nayak
d98b40c075 Documentation/x86/topology: Detail CPUID leaves used for topology enumeration
Add a new section describing the different CPUID leaves and fields used
to parse topology on x86 systems.

  [ bp: Cleanups and simplifications ontop. ]

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/20250901170418.4314-1-kprateek.nayak@amd.com
2025-09-17 11:24:54 +02:00
Mark Brown
220928e52c arm64/hwcap: Add hwcap for FEAT_LSFE
FEAT_LSFE (Large System Float Extension), providing atomic floating point
memory operations, is optional from v9.5. This feature adds no new
architectural stare and we have no immediate use for it in the kernel so
simply provide a hwcap for it to support discovery by userspace.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2025-09-16 19:55:11 +01:00
Mark Brown
3c0979c644 arm64/sme: Drop inaccurate documentation of streaming mode switches
The SME ABI documentation contains an inaccurate description of the
architectural streaming mode entry/exit behaviour, just remove it since
this is better documented by the architecture or with the rest of the
documentation for the specific software interfaces concerned.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2025-09-08 13:25:38 +01:00
Kai Huang
5f9b5bd0c8 x86/virt/tdx: Update the kexec section in the TDX documentation
TDX host kernel now supports kexec/kdump.  Update the documentation to
reflect that.

Opportunistically, remove the parentheses in "Kexec()" and move this
section under the "Erratum" section because the updated "Kexec" section
now refers to that erratum.

Signed-off-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Tested-by: Farrah Chen <farrah.chen@intel.com>
Link: https://lore.kernel.org/all/20250901160930.1785244-7-pbonzini%40redhat.com
2025-09-05 10:40:40 -07:00