Merge tag 'docs-5.17' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "This isn't a hugely busy cycle for documentation, but a few
  significant things still showed up:

   - A documentation section for ARC processors

   - Reworked and enhanced KUnit documentation

   - The ability to pick your own theme for HTML builds; if the default
     "Read the Docs" theme isn't ugly enough for you, you can now pick
     an uglier one.

   - More Chinese translation work

  Plus the usual assortment of fixes and cleanups"

* tag 'docs-5.17' of git://git.lwn.net/linux: (53 commits)
  scripts: sphinx-pre-install: Fix ctex support on Debian
  docs: discourage use of list tables
  docs: 5.Posting.rst: describe Fixes: and Link: tags
  Documentation: kgdb: Replace deprecated remotebaud
  docs: automarkup.py: Fix invalid HTML link output and broken URI fragments
  Documentation: refer to config RANDOMIZE_BASE for kernel address-space randomization
  Documentation: kgdb: properly capitalize the MAGIC_SYSRQ config
  docs/zh_CN: Update and fix a couple of typos
  scripts: sphinx-pre-install: add required ctex dependency
  Documentation: KUnit: Restyled Frequently Asked Questions
  Documentation: KUnit: Restyle Test Style and Nomenclature page
  Documentation: KUnit: Rework writing page to focus on writing tests
  Documentation: kunit: Reorganize documentation related to running tests
  Documentation: KUnit: Added KUnit Architecture
  Documentation: KUnit: Rewrite getting started
  Documentation: KUnit: Rewrite main page
  docs/zh_CN: Add zh_CN/accounting/delay-accounting.rst
  Documentation/sphinx: fix typos of "its"
  docs/zh_CN: Add sched-domains translation
  doc: fs: remove bdev_try_to_free_page related doc
  ...

Documentation/Makefile

@@ -19,6 +19,8 @@ endif
 SPHINXBUILD   = sphinx-build
 SPHINXOPTS    =
 SPHINXDIRS    = .
+DOCS_THEME    =
+DOCS_CSS      =
 _SPHINXDIRS   = $(sort $(patsubst $(srctree)/Documentation/%/index.rst,%,$(wildcard $(srctree)/Documentation/*/index.rst)))
 SPHINX_CONF   = conf.py
 PAPER         =
@@ -84,7 +86,10 @@ quiet_cmd_sphinx = SPHINX  $@ --> file://$(abspath $(BUILDDIR)/$3/$4)
 	-D version=$(KERNELVERSION) -D release=$(KERNELRELEASE) \
 	$(ALLSPHINXOPTS) \
 	$(abspath $(srctree)/$(src)/$5) \
-	$(abspath $(BUILDDIR)/$3/$4)
+	$(abspath $(BUILDDIR)/$3/$4) && \
+	if [ "x$(DOCS_CSS)" != "x" ]; then \
+		cp $(if $(patsubst /%,,$(DOCS_CSS)),$(abspath $(srctree)/$(DOCS_CSS)),$(DOCS_CSS)) $(BUILDDIR)/$3/_static/; \
+	fi
 
 htmldocs:
 	@$(srctree)/scripts/sphinx-pre-install --version-check
@@ -154,4 +159,8 @@ dochelp:
 	@echo  '  make SPHINX_CONF={conf-file} [target] use *additional* sphinx-build'
 	@echo  '  configuration. This is e.g. useful to build with nit-picking config.'
 	@echo
+	@echo  '  make DOCS_THEME={sphinx-theme} selects a different Sphinx theme.'
+	@echo
+	@echo  '  make DOCS_CSS={a .css file} adds a DOCS_CSS override file for html/epub output.'
+	@echo
 	@echo  '  Default location for the generated documents is Documentation/output'

Documentation/admin-guide/hw-vuln/spectre.rst

@@ -468,7 +468,7 @@ Spectre variant 2
    before invoking any firmware code to prevent Spectre variant 2 exploits
    using the firmware.
 
-   Using kernel address space randomization (CONFIG_RANDOMIZE_SLAB=y
+   Using kernel address space randomization (CONFIG_RANDOMIZE_BASE=y
    and CONFIG_SLAB_FREELIST_RANDOM=y in the kernel configuration) makes
    attacks on the kernel generally more difficult.
 

Documentation/arc/arc.rst

@@ -0,0 +1,85 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Linux kernel for ARC processors
+*******************************
+
+Other sources of information
+############################
+
+Below are some resources where more information can be found on
+ARC processors and relevant open source projects.
+
+- `<https://embarc.org>`_ - Community portal for open source on ARC.
+  Good place to start to find relevant FOSS projects, toolchain releases,
+  news items and more.
+
+- `<https://github.com/foss-for-synopsys-dwc-arc-processors>`_ -
+  Home for all development activities regarding open source projects for
+  ARC processors. Some of the projects are forks of various upstream projects,
+  where "work in progress" is hosted prior to submission to upstream projects.
+  Other projects are developed by Synopsys and made available to community
+  as open source for use on ARC Processors.
+
+- `Official Synopsys ARC Processors website
+  <https://www.synopsys.com/designware-ip/processor-solutions.html>`_ -
+  location, with access to some IP documentation (`Programmer's Reference
+  Manual, AKA PRM for ARC HS processors
+  <https://www.synopsys.com/dw/doc.php/ds/cc/programmers-reference-manual-ARC-HS.pdf>`_)
+  and free versions of some commercial tools (`Free nSIM
+  <https://www.synopsys.com/cgi-bin/dwarcnsim/req1.cgi>`_ and
+  `MetaWare Light Edition <https://www.synopsys.com/cgi-bin/arcmwtk_lite/reg1.cgi>`_).
+  Please note though, registration is required to access both the documentation and
+  the tools.
+
+Important note on ARC processors configurability
+################################################
+
+ARC processors are highly configurable and several configurable options
+are supported in Linux. Some options are transparent to software
+(i.e cache geometries, some can be detected at runtime and configured
+and used accordingly, while some need to be explicitly selected or configured
+in the kernel's configuration utility (AKA "make menuconfig").
+
+However not all configurable options are supported when an ARC processor
+is to run Linux. SoC design teams should refer to "Appendix E:
+Configuration for ARC Linux" in the ARC HS Databook for configurability
+guidelines.
+
+Following these guidelines and selecting valid configuration options
+up front is critical to help prevent any unwanted issues during
+SoC bringup and software development in general.
+
+Building the Linux kernel for ARC processors
+############################################
+
+The process of kernel building for ARC processors is the same as for any other
+architecture and could be done in 2 ways:
+
+- Cross-compilation: process of compiling for ARC targets on a development
+  host with a different processor architecture (generally x86_64/amd64).
+- Native compilation: process of compiling for ARC on a ARC platform
+  (hardware board or a simulator like QEMU) with complete development environment
+  (GNU toolchain, dtc, make etc) installed on the platform.
+
+In both cases, up-to-date GNU toolchain for ARC for the host is needed.
+Synopsys offers prebuilt toolchain releases which can be used for this purpose,
+available from:
+
+- Synopsys GNU toolchain releases:
+  `<https://github.com/foss-for-synopsys-dwc-arc-processors/toolchain/releases>`_
+
+- Linux kernel compilers collection:
+  `<https://mirrors.edge.kernel.org/pub/tools/crosstool>`_
+
+- Bootlin's toolchain collection: `<https://toolchains.bootlin.com>`_
+
+Once the toolchain is installed in the system, make sure its "bin" folder
+is added in your ``PATH`` environment variable. Then set ``ARCH=arc`` &
+``CROSS_COMPILE=arc-linux`` (or whatever matches installed ARC toolchain prefix)
+and then as usual ``make defconfig && make``.
+
+This will produce "vmlinux" file in the root of the kernel source tree
+usable for loading on the target system via JTAG.
+If you need to get an image usable with U-Boot bootloader,
+type ``make uImage`` and ``uImage`` will be produced in ``arch/arc/boot``
+folder.

Documentation/arc/features.rst

@@ -0,0 +1,3 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. kernel-feat:: $srctree/Documentation/features arc

Documentation/arc/index.rst

@@ -0,0 +1,17 @@
+===================
+ARC architecture
+===================
+
+.. toctree::
+    :maxdepth: 1
+
+    arc
+
+    features
+
+.. only::  subproject and html
+
+   Indices
+   =======
+
+   * :ref:`genindex`

Documentation/arch.rst

@@ -9,6 +9,7 @@ implementation.
 .. toctree::
    :maxdepth: 2
 
+   arc/index
    arm/index
    arm64/index
    ia64/index

Documentation/conf.py

@@ -208,16 +208,86 @@
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
 
-# The Read the Docs theme is available from
-# - https://github.com/snide/sphinx_rtd_theme
-# - https://pypi.python.org/pypi/sphinx_rtd_theme
-# - python-sphinx-rtd-theme package (on Debian)
-try:
-    import sphinx_rtd_theme
-    html_theme = 'sphinx_rtd_theme'
-    html_theme_path = [sphinx_rtd_theme.get_html_theme_path()]
-except ImportError:
-    sys.stderr.write('Warning: The Sphinx \'sphinx_rtd_theme\' HTML theme was not found. Make sure you have the theme installed to produce pretty HTML output. Falling back to the default theme.\n')
+# Default theme
+html_theme = 'sphinx_rtd_theme'
+html_css_files = []
+
+if "DOCS_THEME" in os.environ:
+    html_theme = os.environ["DOCS_THEME"]
+
+if html_theme == 'sphinx_rtd_theme' or html_theme == 'sphinx_rtd_dark_mode':
+    # Read the Docs theme
+    try:
+        import sphinx_rtd_theme
+        html_theme_path = [sphinx_rtd_theme.get_html_theme_path()]
+
+        # Add any paths that contain custom static files (such as style sheets) here,
+        # relative to this directory. They are copied after the builtin static files,
+        # so a file named "default.css" will overwrite the builtin "default.css".
+        html_css_files = [
+            'theme_overrides.css',
+        ]
+
+        # Read the Docs dark mode override theme
+        if html_theme == 'sphinx_rtd_dark_mode':
+            try:
+                import sphinx_rtd_dark_mode
+                extensions.append('sphinx_rtd_dark_mode')
+            except ImportError:
+                html_theme == 'sphinx_rtd_theme'
+
+        if html_theme == 'sphinx_rtd_theme':
+                # Add color-specific RTD normal mode
+                html_css_files.append('theme_rtd_colors.css')
+
+    except ImportError:
+        html_theme = 'classic'
+
+if "DOCS_CSS" in os.environ:
+    css = os.environ["DOCS_CSS"].split(" ")
+
+    for l in css:
+        html_css_files.append(l)
+
+if major <= 1 and minor < 8:
+    html_context = {
+        'css_files': [],
+    }
+
+    for l in html_css_files:
+        html_context['css_files'].append('_static/' + l)
+
+if  html_theme == 'classic':
+    html_theme_options = {
+        'rightsidebar':        False,
+        'stickysidebar':       True,
+        'collapsiblesidebar':  True,
+        'externalrefs':        False,
+
+        'footerbgcolor':       "white",
+        'footertextcolor':     "white",
+        'sidebarbgcolor':      "white",
+        'sidebarbtncolor':     "black",
+        'sidebartextcolor':    "black",
+        'sidebarlinkcolor':    "#686bff",
+        'relbarbgcolor':       "#133f52",
+        'relbartextcolor':     "white",
+        'relbarlinkcolor':     "white",
+        'bgcolor':             "white",
+        'textcolor':           "black",
+        'headbgcolor':         "#f2f2f2",
+        'headtextcolor':       "#20435c",
+        'headlinkcolor':       "#c60f0f",
+        'linkcolor':           "#355f7c",
+        'visitedlinkcolor':    "#355f7c",
+        'codebgcolor':         "#3f3f3f",
+        'codetextcolor':       "white",
+
+        'bodyfont':            "serif",
+        'headfont':            "sans-serif",
+    }
+
+sys.stderr.write("Using %s theme\n" % html_theme)
 
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the
@@ -246,20 +316,8 @@
 # Add any paths that contain custom static files (such as style sheets) here,
 # relative to this directory. They are copied after the builtin static files,
 # so a file named "default.css" will overwrite the builtin "default.css".
-
 html_static_path = ['sphinx-static']
 
-html_css_files = [
-    'theme_overrides.css',
-]
-
-if major <= 1 and minor < 8:
-    html_context = {
-        'css_files': [
-            '_static/theme_overrides.css',
-        ],
-    }
-
 # Add any extra paths that contain custom files (such as robots.txt or
 # .htaccess) here, relative to this directory. These files are copied
 # directly to the root of the documentation.

Documentation/dev-tools/index.rst

@@ -32,6 +32,7 @@ Documentation/dev-tools/testing-overview.rst
    kgdb
    kselftest
    kunit/index
+   ktap
 
 
 .. only::  subproject and html

Documentation/dev-tools/kgdb.rst

@@ -402,7 +402,7 @@ This is a quick example of how to use kdb.
 2. Enter the kernel debugger manually or by waiting for an oops or
    fault. There are several ways you can enter the kernel debugger
    manually; all involve using the :kbd:`SysRq-G`, which means you must have
-   enabled ``CONFIG_MAGIC_SysRq=y`` in your kernel config.
+   enabled ``CONFIG_MAGIC_SYSRQ=y`` in your kernel config.
 
    -  When logged in as root or with a super user session you can run::
 
@@ -461,7 +461,7 @@ This is a quick example of how to use kdb with a keyboard.
 2. Enter the kernel debugger manually or by waiting for an oops or
    fault. There are several ways you can enter the kernel debugger
    manually; all involve using the :kbd:`SysRq-G`, which means you must have
-   enabled ``CONFIG_MAGIC_SysRq=y`` in your kernel config.
+   enabled ``CONFIG_MAGIC_SYSRQ=y`` in your kernel config.
 
    -  When logged in as root or with a super user session you can run::
 
@@ -557,7 +557,7 @@ Connecting with gdb to a serial port
    Example (using a directly connected port)::
 
            % gdb ./vmlinux
-           (gdb) set remotebaud 115200
+           (gdb) set serial baud 115200
            (gdb) target remote /dev/ttyS0