Commit graph

37 commits

Author SHA1 Message Date
Linus Torvalds
ff6135959a A much quieter cycle for documentation (happily), with, one hopes, the bulk
of the churn behind us.  Significant stuff in this pull includes:
 
  - A set of new Chinese translations
  - Italian translation updates
  - A mechanism from Mauro to automatically format Documentation/features
    for the built docs
  - Automatic cross references without explicit :ref: markup
  - A new reset-controller document
  - An extensive new document on reporting problems from Thorsten
 
 That last patch also adds the CC-BY-4.0 license to LICENSES/dual; there was
 some discussion on this, but we seem to have consensus and an ack from Greg
 for that addition.
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Merge tag 'docs-5.11' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "A much quieter cycle for documentation (happily), with, one hopes, the
  bulk of the churn behind us. Significant stuff in this pull includes:

   - A set of new Chinese translations

   - Italian translation updates

   - A mechanism from Mauro to automatically format
     Documentation/features for the built docs

   - Automatic cross references without explicit :ref: markup

   - A new reset-controller document

   - An extensive new document on reporting problems from Thorsten

  That last patch also adds the CC-BY-4.0 license to LICENSES/dual;
  there was some discussion on this, but we seem to have consensus and
  an ack from Greg for that addition"

* tag 'docs-5.11' of git://git.lwn.net/linux: (50 commits)
  docs: fix broken cross reference in translations/zh_CN
  docs: Note that sphinx 1.7 will be required soon
  docs: update requirements to install six module
  docs: reporting-issues: move 'outdated, need help' note to proper place
  docs: Update documentation to reflect what TAINT_CPU_OUT_OF_SPEC means
  docs: add a reset controller chapter to the driver API docs
  docs: make reporting-bugs.rst obsolete
  docs: Add a new text describing how to report bugs
  LICENSES: Add the CC-BY-4.0 license
  Documentation: fix multiple typos found in the admin-guide subdirectory
  Documentation: fix typos found in admin-guide subdirectory
  kernel-doc: Fix example in Nested structs/unions
  docs: clean up sysctl/kernel: titles, version
  docs: trace: fix event state structure name
  docs: nios2: add missing ReST file
  scripts: get_feat.pl: reduce table width for all features output
  scripts: get_feat.pl: change the group by order
  scripts: get_feat.pl: make complete table more coincise
  scripts: kernel-doc: fix parsing function-like typedefs
  Documentation: fix typos found in process, dev-tools, and doc-guide subdirectories
  ...
2020-12-14 16:55:54 -08:00
Linus Torvalds
8ba27ae36b - Add logic to correct MBM total and local values fixing errata SKX99 and BDF102
(Fenghua Yu)
 
 - Cleanups.
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Merge tag 'x86_cache_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cache resource control updates from Borislav Petkov:

 - add logic to correct MBM total and local values fixing errata SKX99
   and BDF102 (Fenghua Yu)

 - cleanups

* tag 'x86_cache_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/resctrl: Clean up unused function parameter in rmdir path
  x86/resctrl: Constify kernfs_ops
  x86/resctrl: Correct MBM total and local values
  Documentation/x86: Rename resctrl_ui.rst and add two errata to the file
2020-12-14 13:53:17 -08:00
Mauro Carvalho Chehab
ed13a92d0f docs: archis: add a per-architecture features list
Add a feature list matrix for each architecture to their
respective Kernel books.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/9c39d4dd93e05c0008205527d2c3450912f029ed.1606748711.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-12-03 15:10:15 -07:00
Jarkko Sakkinen
3fa97bf001 Documentation/x86: Document SGX kernel architecture
Document the Intel SGX kernel architecture. The fine-grained architecture
details can be looked up from Intel SDM Volume 3D.

Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Jethro Beekman <jethro@fortanix.com>
Cc: linux-doc@vger.kernel.org
Link: https://lkml.kernel.org/r/20201112220135.165028-24-jarkko@kernel.org
2020-11-18 18:16:13 +01:00
Fenghua Yu
d1b22e36e3 Documentation/x86: Rename resctrl_ui.rst and add two errata to the file
Intel Memory Bandwidth Monitoring (MBM) counters may report system
memory bandwidth incorrectly on some Intel processors. This is reported
in documented in erratum SKX99, erratum BDF102 and in the RDT reference
manual, see Documentation/x86/index.rst.

To work around the errata, MBM total and local readings are corrected
using a correction factor table.

Since the correction factor table is not publicly documented anywhere,
document the table and the errata in Documentation/x86/resctrl.rst for
future reference.

 [ bp: Move web links to the doc, massage. ]

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20201014004927.1839452-2-fenghua.yu@intel.com
2020-10-27 16:47:00 +01:00
Linus Torvalds
f888bdf982 Devicetree updates for v5.10:
- Update dtc to upstream version v1.6.0-31-gcbca977ea121
 
 - dtx_diff help text reformatting
 
 - Speed-up validation time for binding and dtb checks using json for
   intermediate files
 
 - Add support for running yamllint on DT schema files
 
 - Remove old booting-without-of.rst
 
 - Extend the example schema to address common issues
 
 - Cleanup handling of additionalProperties/unevaluatedProperties
 
 - Ensure all DSI controller schemas reference dsi-controller.yaml
 
 - Vendor prefixes for Zealz, Wandbord/Technexion, Embest RIoT, Rex, DFI,
   and Cisco Meraki
 
 - Convert at25, SPMI bus, TI hwlock, HiSilicon Hi3660 USB3 PHY, Arm
   SP805 watchdog, Arm SP804, and Samsung 11-pin USB connector to DT
   schema
 
 - Convert HiSilicon SoC and syscon bindings to DT schema
 
 - Convert SiFive Risc-V L2 cache, PLIC, PRCI, and PWM to DT schema
 
 - Convert i.MX bindings for w1, crypto, rng, SIM, PM, DDR,
    SATA, vf610 GPIO, and UART to DT schema
 
 - Add i.MX 8M compatible strings
 
 - Add LM81 and DS1780 as trivial devices
 
 - Various missing properties added to fix dtb validation warnings
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Merge tag 'devicetree-for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull devicetree updates from Rob Herring:

 - Update dtc to upstream version v1.6.0-31-gcbca977ea121

 - dtx_diff help text reformatting

 - Speed-up validation time for binding and dtb checks using json for
   intermediate files

 - Add support for running yamllint on DT schema files

 - Remove old booting-without-of.rst

 - Extend the example schema to address common issues

 - Cleanup handling of additionalProperties/unevaluatedProperties

 - Ensure all DSI controller schemas reference dsi-controller.yaml

 - Vendor prefixes for Zealz, Wandbord/Technexion, Embest RIoT, Rex,
   DFI, and Cisco Meraki

 - Convert at25, SPMI bus, TI hwlock, HiSilicon Hi3660 USB3 PHY, Arm
   SP805 watchdog, Arm SP804, and Samsung 11-pin USB connector to DT
   schema

 - Convert HiSilicon SoC and syscon bindings to DT schema

 - Convert SiFive Risc-V L2 cache, PLIC, PRCI, and PWM to DT schema

 - Convert i.MX bindings for w1, crypto, rng, SIM, PM, DDR, SATA, vf610
   GPIO, and UART to DT schema

 - Add i.MX 8M compatible strings

 - Add LM81 and DS1780 as trivial devices

 - Various missing properties added to fix dtb validation warnings

* tag 'devicetree-for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (111 commits)
  dt-bindings: misc: explicitly add #address-cells for slave mode
  spi: dt-bindings: spi-controller: explicitly require #address-cells=<0> for slave mode
  dt: Remove booting-without-of.rst
  dt-bindings: update usb-c-connector example
  dt-bindings: arm: hisilicon: add missing properties into cpuctrl.yaml
  dt-bindings: arm: hisilicon: add missing properties into sysctrl.yaml
  dt-bindings: pwm: imx: document i.MX compatibles
  scripts/dtc: Update to upstream version v1.6.0-31-gcbca977ea121
  dt-bindings: Add running yamllint to dt_binding_check
  dt-bindings: powerpc: Add a schema for the 'sleep' property
  dt-bindings: pinctrl: sirf: Fix typo abitrary
  dt-bindings: pinctrl: qcom: Fix typo abitrary
  dt-bindings: Explicitly allow additional properties in common schemas
  dt-bindings: Use 'additionalProperties' instead of 'unevaluatedProperties'
  dt-bindings: Add missing 'unevaluatedProperties'
  Docs: Fixing spelling errors in Documentation/devicetree/bindings/
  dt-bindings: arm: hisilicon: convert Hi6220 domain controller bindings to json-schema
  dt-bindings: riscv: convert pwm bindings to json-schema
  dt-bindings: riscv: convert plic bindings to json-schema
  dt-bindings: fu540: prci: convert PRCI bindings to json-schema
  ...
2020-10-14 15:31:58 -07:00
Rob Herring
441848282c dt: Remove booting-without-of.rst
booting-without-of.rst is an ancient document that first outlined
Flattened DeviceTree on PowerPC initially. The DT world has evolved a
lot in the 15 years since and booting-without-of.rst is pretty stale.
The name of the document itself is confusing if you don't understand the
evolution from real 'OpenFirmware'. Most of what booting-without-of.rst
contains is now in the DT specification (which evolved out of the
ePAPR). The few things that weren't documented in the DT specification
are now.

All that remains is the boot entry details, so let's move these to arch
specific documents. The exception is arm which already has the same
details documented.

Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mips@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Rob Herring <robh@kernel.org>
2020-10-13 13:33:16 -05:00
Linus Torvalds
9e536c8179 * Ratelimit the message about writes to unrecognized MSRs so that they
don't spam the console log, by Chris Down.
 
 * Document how the /proc/cpuinfo machinery works for future reference,
 by Kyung Min Park, Ricardo Neri and Dave Hansen.
 
 * Correct the current NMI's duration calculation, by Libing Zhou.
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Merge tag 'x86_misc_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull misc x86 fixes fromm Borislav Petkov:

 - Ratelimit the message about writes to unrecognized MSRs so that they
   don't spam the console log (Chris Down)

 - Document how the /proc/cpuinfo machinery works for future reference
   (Kyung Min Park, Ricardo Neri and Dave Hansen)

 - Correct the current NMI's duration calculation (Libing Zhou)

* tag 'x86_misc_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/nmi: Fix nmi_handle() duration miscalculation
  Documentation/x86: Add documentation for /proc/cpuinfo feature flags
  x86/msr: Make source of unrecognised MSR writes unambiguous
  x86/msr: Prevent userspace MSR access from dominating the console
2020-10-12 10:42:23 -07:00
Ashok Raj
4e7b11567d Documentation/x86: Add documentation for SVA (Shared Virtual Addressing)
ENQCMD and Data Streaming Accelerator (DSA) and all of their associated
features are a complicated stack with lots of interconnected pieces.
This documentation provides a big picture overview for all of the
features.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Co-developed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/1600187413-163670-4-git-send-email-fenghua.yu@intel.com
2020-09-17 19:29:42 +02:00
Kyung Min Park
ea4e3bef4c Documentation/x86: Add documentation for /proc/cpuinfo feature flags
/proc/cpuinfo shows features which the kernel supports. Some of these
flags are derived from CPUID, and others are derived from other sources,
including some that are entirely software-based. Currently, there is
not any documentation in the kernel about how /proc/cpuinfo flags are
generated and what it means when they are missing.

Add documentation for /proc/cpuinfo feature flags enumeration.
Document how and when x86 feature flags are used. Also discuss what
their presence or absence mean for the kernel and users.

Suggested-by: Dave Hansen <dave.hansen@intel.com>
Co-developed-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Kyung Min Park <kyung.min.park@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20200831183500.15481-1-kyung.min.park@intel.com
2020-09-01 11:07:15 +02:00
Stephen Kitt
53ace11952 docs: remove MPX from the x86 toc
MPX was removed in commit 45fc24e89b ("x86/mpx: remove MPX from
arch/x86"), this removes the corresponding entry in the x86 toc.

This was suggested by a Sphinx warning.

Signed-off-by: Stephen Kitt <steve@sk2.org>
Fixes: 45fc24e89b ("x86/mpx: remove MPX from arch/x86")
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-02-25 03:10:22 -07:00
Pawan Gupta
a7a248c593 x86/speculation/taa: Add documentation for TSX Async Abort
Add the documenation for TSX Async Abort. Include the description of
the issue, how to check the mitigation state, control the mitigation,
guidance for system administrators.

 [ bp: Add proper SPDX tags, touch ups by Josh and me. ]

Co-developed-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com>

Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Mark Gross <mgross@linux.intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
2019-10-28 08:37:00 +01:00
Mauro Carvalho Chehab
e8d776f20f docs: x86: move two x86-specific files to x86 arch dir
Those two docs belong to the x86 architecture:

   Documentation/Intel-IOMMU.txt -> Documentation/x86/intel-iommu.rst
   Documentation/intel_txt.txt -> Documentation/x86/intel_txt.rst

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-15 11:03:01 -03:00
Mauro Carvalho Chehab
1eecbcdca2 docs: move protection-keys.rst to the core-api book
This document is used by multiple architectures:

	$ echo $(git grep -l  pkey_mprotect arch|cut -d'/' -f 2|sort|uniq)
	alpha arm arm64 ia64 m68k microblaze mips parisc powerpc s390 sh sparc x86 xtensa

So, let's move it to the core book and adjust the links to it
accordingly.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-08 13:42:12 -06:00
Linus Torvalds
fa4bff1650 Merge branch 'x86-mds-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 MDS mitigations from Thomas Gleixner:
 "Microarchitectural Data Sampling (MDS) is a hardware vulnerability
  which allows unprivileged speculative access to data which is
  available in various CPU internal buffers. This new set of misfeatures
  has the following CVEs assigned:

     CVE-2018-12126  MSBDS  Microarchitectural Store Buffer Data Sampling
     CVE-2018-12130  MFBDS  Microarchitectural Fill Buffer Data Sampling
     CVE-2018-12127  MLPDS  Microarchitectural Load Port Data Sampling
     CVE-2019-11091  MDSUM  Microarchitectural Data Sampling Uncacheable Memory

  MDS attacks target microarchitectural buffers which speculatively
  forward data under certain conditions. Disclosure gadgets can expose
  this data via cache side channels.

  Contrary to other speculation based vulnerabilities the MDS
  vulnerability does not allow the attacker to control the memory target
  address. As a consequence the attacks are purely sampling based, but
  as demonstrated with the TLBleed attack samples can be postprocessed
  successfully.

  The mitigation is to flush the microarchitectural buffers on return to
  user space and before entering a VM. It's bolted on the VERW
  instruction and requires a microcode update. As some of the attacks
  exploit data structures shared between hyperthreads, full protection
  requires to disable hyperthreading. The kernel does not do that by
  default to avoid breaking unattended updates.

  The mitigation set comes with documentation for administrators and a
  deeper technical view"

* 'x86-mds-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  x86/speculation/mds: Fix documentation typo
  Documentation: Correct the possible MDS sysfs values
  x86/mds: Add MDSUM variant to the MDS documentation
  x86/speculation/mds: Add 'mitigations=' support for MDS
  x86/speculation/mds: Print SMT vulnerable on MSBDS with mitigations off
  x86/speculation/mds: Fix comment
  x86/speculation/mds: Add SMT warning message
  x86/speculation: Move arch_smt_update() call to after mitigation decisions
  x86/speculation/mds: Add mds=full,nosmt cmdline option
  Documentation: Add MDS vulnerability documentation
  Documentation: Move L1TF to separate directory
  x86/speculation/mds: Add mitigation mode VMWERV
  x86/speculation/mds: Add sysfs reporting for MDS
  x86/speculation/mds: Add mitigation control for MDS
  x86/speculation/mds: Conditionally clear CPU buffers on idle entry
  x86/kvm/vmx: Add MDS protection when L1D Flush is not active
  x86/speculation/mds: Clear CPU buffers on exit to user
  x86/speculation/mds: Add mds_clear_cpu_buffers()
  x86/kvm: Expose X86_FEATURE_MD_CLEAR to guests
  x86/speculation/mds: Add BUG_MSBDS_ONLY
  ...
2019-05-14 07:57:29 -07:00
Changbin Du
bbea90bbb6 Documentation: x86: convert x86_64/boot-options.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:11 -06:00
Changbin Du
8fffdc9353 Documentation: x86: convert i386/IO-APIC.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:11 -06:00
Changbin Du
71892b25fc Documentation: x86: convert usb-legacy-support.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:11 -06:00
Changbin Du
9d12f58fe9 Documentation: x86: convert orc-unwinder.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:11 -06:00
Changbin Du
1cd7af509d Documentation: x86: convert resctrl_ui.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:11 -06:00
Changbin Du
3d07bc393f Documentation: x86: convert microcode.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:11 -06:00
Changbin Du
ea0765e835 Documentation: x86: convert pti.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:10 -06:00
Changbin Du
0c7180f2e4 Documentation: x86: convert amd-memory-encryption.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:10 -06:00
Changbin Du
f10b07a01a Documentation: x86: convert intel_mpx.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:10 -06:00
Changbin Du
28e21eac94 Documentation: x86: convert protection-keys.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:10 -06:00
Changbin Du
2f6eae4730 Documentation: x86: convert pat.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:10 -06:00
Changbin Du
26d14a2025 Documentation: x86: convert mtrr.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:10 -06:00
Changbin Du
17156044b1 Documentation: x86: convert tlb.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:10 -06:00
Changbin Du
0c2d3639a8 Documentation: x86: convert zero-page.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:10 -06:00
Changbin Du
4b13576002 Documentation: x86: convert earlyprintk.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:10 -06:00
Changbin Du
c2dea5cda0 Documentation: x86: convert entry_64.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:09 -06:00
Changbin Du
ac2b4687da Documentation: x86: convert kernel-stacks to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:09 -06:00
Changbin Du
06955392a9 Documentation: x86: convert exception-tables.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:09 -06:00
Changbin Du
848942cb2e Documentation: x86: convert topology.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:09 -06:00
Changbin Du
f1f238a9f1 Documentation: x86: convert boot.txt to reST
This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:09 -06:00
Changbin Du
e5def4c603 Documentation: add Linux x86 docs to Sphinx TOC tree
Add a index.rst for x86 support. More docs will be added later.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08 14:34:09 -06:00
Thomas Gleixner
6a9e529272 x86/speculation/mds: Add mds_clear_cpu_buffers()
The Microarchitectural Data Sampling (MDS) vulernabilities are mitigated by
clearing the affected CPU buffers. The mechanism for clearing the buffers
uses the unused and obsolete VERW instruction in combination with a
microcode update which triggers a CPU buffer clear when VERW is executed.

Provide a inline function with the assembly magic. The argument of the VERW
instruction must be a memory operand as documented:

  "MD_CLEAR enumerates that the memory-operand variant of VERW (for
   example, VERW m16) has been extended to also overwrite buffers affected
   by MDS. This buffer overwriting functionality is not guaranteed for the
   register operand variant of VERW."

Documentation also recommends to use a writable data segment selector:

  "The buffer overwriting occurs regardless of the result of the VERW
   permission check, as well as when the selector is null or causes a
   descriptor load segment violation. However, for lowest latency we
   recommend using a selector that indicates a valid writable data
   segment."

Add x86 specific documentation about MDS and the internal workings of the
mitigation.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06 21:52:12 +01:00