Merge remote-tracking branch 'jc_docs/docs-next'

17 files changed, 730 insertions, 49 deletions

diff --git a/Documentation/Makefile b/Documentation/Makefile
index a42320385df3..d75c00e3aadb 100644
--- a/Documentation/Makefile
+++ b/Documentation/Makefile
@@ -95,16 +95,6 @@ endif # HAVE_SPHINX
 # The following targets are independent of HAVE_SPHINX, and the rules should
 # work or silently pass without Sphinx.
 
-# no-ops for the Sphinx toolchain
-sgmldocs:
-	@:
-psdocs:
-	@:
-mandocs:
-	@:
-installmandocs:
-	@:
-
 cleandocs:
 	$(Q)rm -rf $(BUILDDIR)
 	$(Q)$(MAKE) BUILDDIR=$(abspath $(BUILDDIR)) $(build)=Documentation/media clean
diff --git a/Documentation/arm/firmware.txt b/Documentation/arm/firmware.txt
index da6713adac8a..7f175dbb427e 100644
--- a/Documentation/arm/firmware.txt
+++ b/Documentation/arm/firmware.txt
@@ -60,7 +60,7 @@ Example of using a firmware operation:
 
 	/* some platform code, e.g. SMP initialization */
 
-	__raw_writel(virt_to_phys(exynos4_secondary_startup),
+	__raw_writel(__pa_symbol(exynos4_secondary_startup),
 		CPU1_BOOT_REG);
 
 	/* Call Exynos specific smc call */
diff --git a/Documentation/dev-tools/gdb-kernel-debugging.rst b/Documentation/dev-tools/gdb-kernel-debugging.rst
index 5e93c9bc6619..19df79286f00 100644
--- a/Documentation/dev-tools/gdb-kernel-debugging.rst
+++ b/Documentation/dev-tools/gdb-kernel-debugging.rst
@@ -31,11 +31,13 @@ Setup
   CONFIG_DEBUG_INFO_REDUCED off. If your architecture supports
   CONFIG_FRAME_POINTER, keep it enabled.
 
-- Install that kernel on the guest.
+- Install that kernel on the guest, turn off KASLR if necessary by adding
+  "nokaslr" to the kernel command line.
   Alternatively, QEMU allows to boot the kernel directly using -kernel,
   -append, -initrd command line switches. This is generally only useful if
   you do not depend on modules. See QEMU documentation for more details on
-  this mode.
+  this mode. In this case, you should build the kernel with
+  CONFIG_RANDOMIZE_BASE disabled if the architecture supports KASLR.
 
 - Enable the gdb stub of QEMU/KVM, either
 
diff --git a/Documentation/dev-tools/kgdb.rst b/Documentation/dev-tools/kgdb.rst
index 75273203a35a..d38be58f872a 100644
--- a/Documentation/dev-tools/kgdb.rst
+++ b/Documentation/dev-tools/kgdb.rst
@@ -348,6 +348,15 @@ default behavior is always set to 0.
     - ``echo 1 > /sys/module/debug_core/parameters/kgdbreboot``
     - Enter the debugger on reboot notify.
 
+Kernel parameter: ``nokaslr``
+-----------------------------
+
+If the architecture that you are using enable KASLR by default,
+you should consider turning it off.  KASLR randomizes the
+virtual address where the kernel image is mapped and confuse
+gdb which resolve kernel symbol address from symbol table
+of vmlinux.
+
 Using kdb
 =========
 
@@ -358,7 +367,7 @@ This is a quick example of how to use kdb.
 
 1. Configure kgdboc at boot using kernel parameters::
 
-	console=ttyS0,115200 kgdboc=ttyS0,115200
+	console=ttyS0,115200 kgdboc=ttyS0,115200 nokaslr
 
    OR
 
diff --git a/Documentation/doc-guide/sphinx.rst b/Documentation/doc-guide/sphinx.rst
index 84e8e8a9cbdb..8faafb9b2d86 100644
--- a/Documentation/doc-guide/sphinx.rst
+++ b/Documentation/doc-guide/sphinx.rst
@@ -19,6 +19,112 @@ Finally, there are thousands of plain text documentation files scattered around
 ``Documentation``. Some of these will likely be converted to reStructuredText
 over time, but the bulk of them will remain in plain text.
 
+.. _sphinx_install:
+
+Sphinx Install
+==============
+
+The ReST markups currently used by the Documentation/ files are meant to be
+built with ``Sphinx`` version 1.3 or upper. If you're desiring to build
+PDF outputs, it is recommended to use version 1.4.6 or upper.
+
+There's a script that checks for the Spinx requirements. Please see
+:ref:`sphinx-pre-install` for further details.
+
+Most distributions are shipped with Sphinx, but its toolchain is fragile,
+and it is not uncommon that upgrading it or some other Python packages
+on your machine would cause the documentation build to break.
+
+A way to get rid of that is to use a different version than the one shipped
+on your distributions. In order to do that, it is recommended to install
+Sphinx inside a virtual environment, using ``virtualenv-3``
+or ``virtualenv``, depending on how your distribution packaged Python 3.
+
+.. note::
+
+   #) Sphinx versions below 1.5 don't work properly with Python's
+      docutils version 0.13.1 or upper. So, if you're willing to use
+      those versions, you should run ``pip install 'docutils==0.12'``.
+
+   #) It is recommended to use the RTD theme for html output. Depending
+      on the Sphinx version, it should be installed  in separate,
+      with ``pip install sphinx_rtd_theme``.
+
+   #) Some ReST pages contain math expressions. Due to the way Sphinx work,
+      those expressions are written using LaTeX notation. It needs texlive
+      installed with amdfonts and amsmath in order to evaluate them.
+
+In summary, if you want to install Sphinx version 1.4.9, you should do::
+
+       $ virtualenv sphinx_1.4
+       $ . sphinx_1.4/bin/activate
+       (sphinx_1.4) $ pip install -r Documentation/sphinx/requirements.txt
+
+After running ``. sphinx_1.4/bin/activate``, the prompt will change,
+in order to indicate that you're using the new environment. If you
+open a new shell, you need to rerun this command to enter again at
+the virtual environment before building the documentation.
+
+Image output
+------------
+
+The kernel documentation build system contains an extension that
+handles images on both GraphViz and SVG formats (see
+:ref:`sphinx_kfigure`).
+
+For it to work, you need to install both GraphViz and ImageMagick
+packages. If those packages are not installed, the build system will
+still build the documentation, but won't include any images at the
+output.
+
+PDF and LaTeX builds
+--------------------
+
+Such builds are currently supported only with Sphinx versions 1.4 and 1.5.
+
+Currently, it is not possible to do pdf builds with Sphinx version 1.6.
+
+For PDF and LaTeX output, you'll also need ``XeLaTeX`` version 3.14159265.
+
+Depending on the distribution, you may also need to install a series of
+``texlive`` packages that provide the minimal set of functionalities
+required for ``XeLaTeX`` to work.
+
+.. _sphinx-pre-install:
+
+Checking for Sphinx dependencies
+--------------------------------
+
+There's a script that automatically check for Sphinx dependencies. If it can
+recognize your distribution, it will also give a hint about the install
+command line options for your distro::
+
+	$ ./scripts/sphinx-pre-install
+	Checking if the needed tools for Fedora release 26 (Twenty Six) are available
+	Warning: better to also install "texlive-luatex85".
+	You should run:
+
+		sudo dnf install -y texlive-luatex85
+		/usr/bin/virtualenv sphinx_1.4
+		. sphinx_1.4/bin/activate
+		pip install -r Documentation/sphinx/requirements.txt
+
+	Can't build as 1 mandatory dependency is missing at ./scripts/sphinx-pre-install line 468.
+
+By default, it checks all the requirements for both html and PDF, including
+the requirements for images, math expressions and LaTeX build, and assumes
+that a virtual Python environment will be used. The ones needed for html
+builds are assumed to be mandatory; the others to be optional.
+
+It supports two optional parameters:
+
+``--no-pdf``
+	Disable checks for PDF;
+
+``--no-virtualenv``
+	Use OS packaging for Sphinx instead of Python virtual environment.
+
+
 Sphinx Build
 ============
 
@@ -118,7 +224,7 @@ Here are some specific guidelines for the kernel documentation:
 the C domain
 ------------
 
-The `Sphinx C Domain`_ (name c) is suited for documentation of C API. E.g. a
+The **Sphinx C Domain** (name c) is suited for documentation of C API. E.g. a
 function prototype:
 
 .. code-block:: rst
@@ -229,6 +335,7 @@ Rendered as:
 
         - column 3
 
+.. _sphinx_kfigure:
 
 Figures & Images
 ================
diff --git a/Documentation/driver-api/basics.rst b/Documentation/driver-api/basics.rst
index ab82250c7727..73fa7d42bbba 100644
--- a/Documentation/driver-api/basics.rst
+++ b/Documentation/driver-api/basics.rst
@@ -4,7 +4,7 @@ Driver Basics
 Driver Entry and Exit points
 ----------------------------
 
-.. kernel-doc:: include/linux/init.h
+.. kernel-doc:: include/linux/module.h
    :internal:
 
 Driver device table
@@ -103,9 +103,6 @@ Kernel utility functions
 .. kernel-doc:: kernel/panic.c
    :export:
 
-.. kernel-doc:: kernel/sys.c
-   :export:
-
 .. kernel-doc:: kernel/rcu/tree.c
    :export:
 
diff --git a/Documentation/driver-api/dma-buf.rst b/Documentation/driver-api/dma-buf.rst
index 31671b469627..dc384f2f7f34 100644
--- a/Documentation/driver-api/dma-buf.rst
+++ b/Documentation/driver-api/dma-buf.rst
@@ -139,9 +139,6 @@ DMA Fences
 Seqno Hardware Fences
 ~~~~~~~~~~~~~~~~~~~~~
 
-.. kernel-doc:: drivers/dma-buf/seqno-fence.c
-   :export:
-
 .. kernel-doc:: include/linux/seqno-fence.h
    :internal:
 
diff --git a/Documentation/driver-api/s390-drivers.rst b/Documentation/driver-api/s390-drivers.rst
index 7060da136095..ecf8851d3565 100644
--- a/Documentation/driver-api/s390-drivers.rst
+++ b/Documentation/driver-api/s390-drivers.rst
@@ -75,7 +75,7 @@ The channel-measurement facility provides a means to collect measurement
 data which is made available by the channel subsystem for each channel
 attached device.
 
-.. kernel-doc:: arch/s390/include/asm/cmb.h
+.. kernel-doc:: arch/s390/include/uapi/asm/cmb.h
    :internal:
 
 .. kernel-doc:: drivers/s390/cio/cmf.c
diff --git a/Documentation/driver-api/scsi.rst b/Documentation/driver-api/scsi.rst
index 859fb672319f..5a2aa7a377d9 100644
--- a/Documentation/driver-api/scsi.rst
+++ b/Documentation/driver-api/scsi.rst
@@ -224,14 +224,6 @@ mid to lowlevel SCSI driver interface
 .. kernel-doc:: drivers/scsi/hosts.c
    :export:
 
-drivers/scsi/constants.c
-~~~~~~~~~~~~~~~~~~~~~~~~
-
-mid to lowlevel SCSI driver interface
-
-.. kernel-doc:: drivers/scsi/constants.c
-   :export:
-
 Transport classes
 -----------------
 
diff --git a/Documentation/gpu/drm-mm.rst b/Documentation/gpu/drm-mm.rst
index 9412798645c1..300898298bf6 100644
--- a/Documentation/gpu/drm-mm.rst
+++ b/Documentation/gpu/drm-mm.rst
@@ -492,7 +492,7 @@ DRM Sync Objects
    :doc: Overview
 
 .. kernel-doc:: include/drm/drm_syncobj.h
-   :export:
+   :internal:
 
 .. kernel-doc:: drivers/gpu/drm/drm_syncobj.c
    :export:
diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst
index adbb50ae5246..560beaef5a7c 100644
--- a/Documentation/process/changes.rst
+++ b/Documentation/process/changes.rst
@@ -53,7 +53,7 @@ mcelog                 0.6              mcelog --version
 iptables               1.4.2            iptables -V
 openssl & libcrypto    1.0.0            openssl version
 bc                     1.06.95          bc --version
-Sphinx\ [#f1]_	       1.2		sphinx-build --version
+Sphinx\ [#f1]_	       1.3		sphinx-build --version
 ====================== ===============  ========================================
 
 .. [#f1] Sphinx is needed only to build the Kernel documentation
@@ -309,18 +309,8 @@ Kernel documentation
 Sphinx
 ------
 
-The ReST markups currently used by the Documentation/ files are meant to be
-built with ``Sphinx`` version 1.2 or upper. If you're desiring to build
-PDF outputs, it is recommended to use version 1.4.6.
-
-.. note::
-
-  Please notice that, for PDF and LaTeX output, you'll also need ``XeLaTeX``
-  version 3.14159265. Depending on the distribution, you may also need to
-  install a series of ``texlive`` packages that provide the minimal set of
-  functionalities required for ``XeLaTex`` to work. For PDF output you'll also
-  need ``convert(1)`` from ImageMagick (https://www.imagemagick.org).
-
+Please see :ref:`sphinx_install` in ``Documentation/doc-guide/sphinx.rst``
+for details about Sphinx requirements.
 
 Getting updated software
 ========================
diff --git a/Documentation/process/submitting-patches.rst b/Documentation/process/submitting-patches.rst
index 3e10719fee35..733478ade91b 100644
--- a/Documentation/process/submitting-patches.rst
+++ b/Documentation/process/submitting-patches.rst
@@ -413,7 +413,7 @@ e-mail discussions.
 
 
 
-11) Sign your work — the Developer's Certificate of Origin
+11) Sign your work - the Developer's Certificate of Origin
 ----------------------------------------------------------
 
 To improve tracking of who did what, especially with patches that can
diff --git a/Documentation/sphinx-static/theme_overrides.css b/Documentation/sphinx-static/theme_overrides.css
index d5764a4de5a2..522b6d4c49d4 100644
--- a/Documentation/sphinx-static/theme_overrides.css
+++ b/Documentation/sphinx-static/theme_overrides.css
@@ -4,6 +4,17 @@
  *
  */
 
+/* Interim: Code-blocks with line nos - lines and line numbers don't line up.
+ * see: https://github.com/rtfd/sphinx_rtd_theme/issues/419
+ */
+
+div[class^="highlight"] pre {
+    line-height: normal;
+}
+.rst-content .highlight > pre {
+    line-height: normal;
+}
+
 @media screen {
 
     /* content column
@@ -56,6 +67,12 @@
 	font-family: "Courier New", Courier, monospace
     }
 
+    /* fix bottom margin of lists items */
+
+    .rst-content .section ul li:last-child, .rst-content .section ul li p:last-child {
+          margin-bottom: 12px;
+    }
+
     /* inline literal: drop the borderbox, padding and red color */
 
     code, .rst-content tt, .rst-content code {
diff --git a/Documentation/sphinx/requirements.txt b/Documentation/sphinx/requirements.txt
new file mode 100644
index 000000000000..742be3e12619
--- /dev/null
+++ b/Documentation/sphinx/requirements.txt
@@ -0,0 +1,3 @@
+docutils==0.12
+Sphinx==1.4.9
+sphinx_rtd_theme
diff --git a/Documentation/translations/zh_CN/HOWTO b/Documentation/translations/zh_CN/HOWTO
index 11be075ba5fa..5f6d09edc9ac 100644
--- a/Documentation/translations/zh_CN/HOWTO
+++ b/Documentation/translations/zh_CN/HOWTO
@@ -149,9 +149,7 @@ Linux内核代码中包含有大量的文档。这些文档对于学习如何与
 核源码的主目录中使用以下不同命令将会分别生成PDF、Postscript、HTML和手册
 页等不同格式的文档：
     make pdfdocs
-    make psdocs
     make htmldocs
-    make mandocs
 
 
 如何成为内核开发者
diff --git a/Makefile b/Makefile
index 0662b5201d3e..50cdfbbb1c43 100644
--- a/Makefile
+++ b/Makefile
@@ -1467,7 +1467,7 @@ $(help-board-dirs): help-%:
 
 # Documentation targets
 # ---------------------------------------------------------------------------
-DOC_TARGETS := xmldocs sgmldocs psdocs latexdocs pdfdocs htmldocs mandocs installmandocs epubdocs cleandocs linkcheckdocs
+DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs linkcheckdocs
 PHONY += $(DOC_TARGETS)
 $(DOC_TARGETS): scripts_basic FORCE
 	$(Q)$(MAKE) $(build)=Documentation $@
diff --git a/scripts/sphinx-pre-install b/scripts/sphinx-pre-install
new file mode 100755
index 000000000000..5d2799dcfceb
--- /dev/null
+++ b/scripts/sphinx-pre-install
@@ -0,0 +1,579 @@
+#!/usr/bin/perl
+use strict;
+
+# Copyright (c) 2017 Mauro Carvalho Chehab <mchehab@kernel.org>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+my $virtenv_dir = "sphinx_1.4";
+my $requirement_file = "Documentation/sphinx/requirements.txt";
+
+#
+# Static vars
+#
+
+my %missing;
+my $system_release;
+my $need = 0;
+my $optional = 0;
+my $need_symlink = 0;
+my $need_sphinx = 0;
+my $install = "";
+
+#
+# Command line arguments
+#
+
+my $pdf = 1;
+my $virtualenv = 1;
+
+#
+# List of required texlive packages on Fedora and OpenSuse
+#
+
+my %texlive = (
+	'adjustbox.sty'      => 'texlive-adjustbox',
+	'amsfonts.sty'       => 'texlive-amsfonts',
+	'amsmath.sty'        => 'texlive-amsmath',
+	'amssymb.sty'        => 'texlive-amsfonts',
+	'amsthm.sty'         => 'texlive-amscls',
+	'anyfontsize.sty'    => 'texlive-anyfontsize',
+	'atbegshi.sty'       => 'texlive-oberdiek',
+	'bm.sty'             => 'texlive-tools',
+	'capt-of.sty'        => 'texlive-capt-of',
+	'cmap.sty'           => 'texlive-cmap',
+	'ecrm1000.tfm'       => 'texlive-ec',
+	'eqparbox.sty'       => 'texlive-eqparbox',
+	'eu1enc.def'         => 'texlive-euenc',
+	'fancybox.sty'       => 'texlive-fancybox',
+	'fancyvrb.sty'       => 'texlive-fancyvrb',
+	'float.sty'          => 'texlive-float',
+	'fncychap.sty'       => 'texlive-fncychap',
+	'footnote.sty'       => 'texlive-mdwtools',
+	'framed.sty'         => 'texlive-framed',
+	'luatex85.sty'       => 'texlive-luatex85',
+	'multirow.sty'       => 'texlive-multirow',
+	'needspace.sty'      => 'texlive-needspace',
+	'palatino.sty'       => 'texlive-psnfss',
+	'parskip.sty'        => 'texlive-parskip',
+	'polyglossia.sty'    => 'texlive-polyglossia',
+	'tabulary.sty'       => 'texlive-tabulary',
+	'threeparttable.sty' => 'texlive-threeparttable',
+	'titlesec.sty'       => 'texlive-titlesec',
+	'ucs.sty'            => 'texlive-ucs',
+	'upquote.sty'        => 'texlive-upquote',
+	'wrapfig.sty'        => 'texlive-wrapfig',
+);
+
+#
+# Subroutines that checks if a feature exists
+#
+
+sub check_missing(%)
+{
+	my %map = %{$_[0]};
+
+	foreach my $prog (sort keys %missing) {
+		my $is_optional = $missing{$prog};
+
+		if ($is_optional) {
+			print "Warning: better to also install \"$prog\".\n";
+		} else {
+			print "ERROR: please install \"$prog\", otherwise, build won't work.\n";
+		}
+		if (defined($map{$prog})) {
+			$install .= " " . $map{$prog};
+		} else {
+			$install .= " " . $prog;
+		}
+	}
+
+	$install =~ s/^\s//;
+}
+
+sub add_package($$)
+{
+	my $package = shift;
+	my $is_optional = shift;
+
+	$missing{$package} = $is_optional;
+	if ($is_optional) {
+		$optional++;
+	} else {
+		$need++;
+	}
+}
+
+sub check_missing_file($$$)
+{
+	my $file = shift;
+	my $package = shift;
+	my $is_optional = shift;
+
+	return if(-e $file);
+
+	add_package($package, $is_optional);
+}
+
+sub findprog($)
+{
+	foreach(split(/:/, $ENV{PATH})) {
+		return "$_/$_[0]" if(-x "$_/$_[0]");
+	}
+}
+
+sub check_program($$)
+{
+	my $prog = shift;
+	my $is_optional = shift;
+
+	return if findprog($prog);
+
+	add_package($prog, $is_optional);
+}
+
+sub check_perl_module($$)
+{
+	my $prog = shift;
+	my $is_optional = shift;
+
+	my $err = system("perl -M$prog -e 1 2>/dev/null /dev/null");
+	return if ($err == 0);
+
+	add_package($prog, $is_optional);
+}
+
+sub check_python_module($$)
+{
+	my $prog = shift;
+	my $is_optional = shift;
+
+	my $err = system("python3 -c 'import $prog' 2>/dev/null /dev/null");
+	return if ($err == 0);
+	my $err = system("python -c 'import $prog' 2>/dev/null /dev/null");
+	return if ($err == 0);
+
+	add_package($prog, $is_optional);
+}
+
+sub check_rpm_missing($$)
+{
+	my @pkgs = @{$_[0]};
+	my $is_optional = $_[1];
+
+	foreach my $prog(@pkgs) {
+		my $err = system("rpm -q '$prog' 2>/dev/null >/dev/null");
+		add_package($prog, $is_optional) if ($err);
+	}
+}
+
+sub check_pacman_missing($$)
+{
+	my @pkgs = @{$_[0]};
+	my $is_optional = $_[1];
+
+	foreach my $prog(@pkgs) {
+		my $err = system("pacman -Q '$prog' 2>/dev/null >/dev/null");
+		add_package($prog, $is_optional) if ($err);
+	}
+}
+
+sub check_missing_tex($)
+{
+	my $is_optional = shift;
+	my $kpsewhich = findprog("kpsewhich");
+
+	foreach my $prog(keys %texlive) {
+		my $package = $texlive{$prog};
+		if (!$kpsewhich) {
+			add_package($package, $is_optional);
+			next;
+		}
+		my $file = qx($kpsewhich $prog);
+		add_package($package, $is_optional) if ($file =~ /^\s*$/);
+	}
+}
+
+sub check_sphinx()
+{
+	return if findprog("sphinx-build");
+
+	if (findprog("sphinx-build-3")) {
+		$need_symlink = 1;
+		return;
+	}
+
+	if ($virtualenv) {
+		my $prog = findprog("virtualenv-3");
+		$prog = findprog("virtualenv-3.5") if (!$prog);
+
+		check_program("virtualenv", 0) if (!$prog);
+		check_program("pip", 0) if (!findprog("pip3"));
+		$need_sphinx = 1;
+	} else {
+		add_package("python-sphinx", 0);
+	}
+}
+
+#
+# Ancillary subroutines
+#
+
+sub catcheck($)
+{
+  my $res = "";
+  $res = qx(cat $_[0]) if (-r $_[0]);
+  return $res;
+}
+
+sub which($)
+{
+	my $file = shift;
+	my @path = split ":", $ENV{PATH};
+
+	foreach my $dir(@path) {
+		my $name = $dir.'/'.$file;
+		return $name if (-x $name );
+	}
+	return undef;
+}
+
+#
+# Subroutines that check distro-specific hints
+#
+
+sub give_debian_hints()
+{
+	my %map = (
+		"python-sphinx"		=> "python3-sphinx",
+		"sphinx_rtd_theme"	=> "python3-sphinx-rtd-theme",
+		"virtualenv"		=> "virtualenv",
+		"pip"			=> "python3-pip",
+		"dot"			=> "graphviz",
+		"convert"		=> "imagemagick",
+		"Pod::Usage"		=> "perl-modules",
+		"xelatex"		=> "texlive-xetex",
+		"rsvg-convert"		=> "librsvg2-bin",
+	);
+
+	if ($pdf) {
+		check_missing_file("/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf",
+				   "fonts-dejavu", 1);
+	}
+
+	check_program("dvipng", 1) if ($pdf);
+	check_missing(\%map);
+
+	return if (!$need && !$optional);
+	printf("You should run:\n\n\tsudo apt-get install $install\n");
+}
+
+sub give_redhat_hints()
+{
+	my %map = (
+		"python-sphinx"		=> "python3-sphinx",
+		"sphinx_rtd_theme"	=> "python3-sphinx_rtd_theme",
+		"virtualenv"		=> "python3-virtualenv",
+		"pip"			=> "python3-pip",
+		"dot"			=> "graphviz",
+		"convert"		=> "ImageMagick",
+		"Pod::Usage"		=> "perl-Pod-Usage",
+		"xelatex"		=> "texlive-xetex-bin",
+		"rsvg-convert"		=> "librsvg2-tools",
+	);
+
+	my @fedora26_opt_pkgs = (
+		"graphviz-gd",		# Fedora 26: needed for PDF support
+	);
+
+	my @fedora_tex_pkgs = (
+		"texlive-collection-fontsrecommended",
+		"texlive-collection-latex",
+		"dejavu-sans-fonts",
+		"dejavu-serif-fonts",
+		"dejavu-sans-mono-fonts",
+	);
+
+	my $release;
+
+	$release = $1 if ($system_release =~ /Fedora\s+release\s+(\d+)/);
+
+	check_rpm_missing(\@fedora26_opt_pkgs, 1) if ($pdf && $release >= 26);
+	check_rpm_missing(\@fedora_tex_pkgs, 1) if ($pdf);
+	check_missing_tex(1) if ($pdf);
+	check_missing(\%map);
+
+	return if (!$need && !$optional);
+	printf("You should run:\n\n\tsudo dnf install -y $install\n");
+}
+
+sub give_opensuse_hints()
+{
+	my %map = (
+		"python-sphinx"		=> "python3-sphinx",
+		"sphinx_rtd_theme"	=> "python3-sphinx_rtd_theme",
+		"virtualenv"		=> "python3-virtualenv",
+		"pip"			=> "python3-pip",
+		"dot"			=> "graphviz",
+		"convert"		=> "ImageMagick",
+		"Pod::Usage"		=> "perl-Pod-Usage",
+		"xelatex"		=> "texlive-xetex-bin",
+		"rsvg-convert"		=> "rsvg-view",
+	);
+
+	my @suse_tex_pkgs = (
+		"texlive-babel-english",
+		"texlive-caption",
+		"texlive-colortbl",
+		"texlive-courier",
+		"texlive-dvips",
+		"texlive-helvetic",
+		"texlive-makeindex",
+		"texlive-metafont",
+		"texlive-metapost",
+		"texlive-palatino",
+		"texlive-preview",
+		"texlive-times",
+		"texlive-zapfchan",
+		"texlive-zapfding",
+	);
+
+	check_rpm_missing(\@suse_tex_pkgs, 1) if ($pdf);
+	check_missing_tex(1) if ($pdf);
+	check_missing(\%map);
+
+	return if (!$need && !$optional);
+	printf("You should run:\n\n\tsudo zypper install --no-recommends $install\n");
+}
+
+sub give_mageia_hints()
+{
+	my %map = (
+		"python-sphinx"		=> "python3-sphinx",
+		"sphinx_rtd_theme"	=> "python3-sphinx_rtd_theme",
+		"virtualenv"		=> "python3-virtualenv",
+		"pip"			=> "python3-pip",
+		"dot"			=> "graphviz",
+		"convert"		=> "ImageMagick",
+		"Pod::Usage"		=> "perl-Pod-Usage",
+		"xelatex"		=> "texlive",
+		"rsvg-convert"		=> "librsvg2-tools",
+	);
+
+	my @tex_pkgs = (
+		"texlive-fontsextra",
+	);
+
+	my $release;
+
+	check_rpm_missing(\@tex_pkgs, 1) if ($pdf);
+	check_missing(\%map);
+
+	return if (!$need && !$optional);
+	printf("You should run:\n\n\tsudo urpmi $install\n");
+}
+
+sub give_arch_linux_hints()
+{
+	my %map = (
+		"sphinx_rtd_theme"	=> "python-sphinx_rtd_theme",
+		"virtualenv"		=> "python-virtualenv",
+		"pip"			=> "python-pip",
+		"dot"			=> "graphviz",
+		"convert"		=> "imagemagick",
+		"xelatex"		=> "texlive-bin",
+		"rsvg-convert"		=> "extra/librsvg",
+	);
+
+	my @archlinux_tex_pkgs = (
+		"texlive-core",
+		"texlive-latexextra",
+		"ttf-dejavu",
+	);
+	check_pacman_missing(\@archlinux_tex_pkgs, 1) if ($pdf);
+	check_missing(\%map);
+
+	return if (!$need && !$optional);
+	printf("You should run:\n\n\tsudo pacman -S $install\n");
+}
+
+sub give_gentoo_hints()
+{
+	my %map = (
+		"sphinx_rtd_theme"	=> "dev-python/sphinx_rtd_theme",
+		"virtualenv"		=> "dev-python/virtualenv",
+		"pip"			=> "dev-python/pip",
+		"dot"			=> "media-gfx/graphviz",
+		"convert"		=> "media-gfx/imagemagick",
+		"xelatex"		=> "dev-texlive/texlive-xetex media-fonts/dejavu",
+		"rsvg-convert"		=> "gnome-base/librsvg",
+	);
+
+	check_missing_file("/usr/share/fonts/dejavu/DejaVuSans.ttf",
+			   "media-fonts/dejavu", 1) if ($pdf);
+
+	check_missing(\%map);
+
+	return if (!$need && !$optional);
+
+	printf("You should run:\n\n");
+	printf("\tsudo su -c 'echo \"media-gfx/imagemagick svg png\" > /etc/portage/package.use/imagemagick'\n");
+	printf("\tsudo su -c 'echo \"media-gfx/graphviz cairo pdf\" > /etc/portage/package.use/graphviz'\n");
+	printf("\tsudo emerge --ask $install\n");
+
+}
+
+sub check_distros()
+{
+	# Distro-specific hints
+	if ($system_release =~ /Red Hat Enterprise Linux/) {
+		give_redhat_hints;
+		return;
+	}
+	if ($system_release =~ /Fedora/) {
+		give_redhat_hints;
+		return;
+	}
+	if ($system_release =~ /Ubuntu/) {
+		give_debian_hints;
+		return;
+	}
+	if ($system_release =~ /Debian/) {
+		give_debian_hints;
+		return;
+	}
+	if ($system_release =~ /openSUSE/) {
+		give_opensuse_hints;
+		return;
+	}
+	if ($system_release =~ /Mageia/) {
+		give_mageia_hints;
+		return;
+	}
+	if ($system_release =~ /Arch Linux/) {
+		give_arch_linux_hints;
+		return;
+	}
+	if ($system_release =~ /Gentoo/) {
+		give_gentoo_hints;
+		return;
+	}
+
+	#
+	# Fall-back to generic hint code for other distros
+	# That's far from ideal, specially for LaTeX dependencies.
+	#
+	my %map = (
+		"sphinx-build" => "sphinx"
+	);
+	check_missing_tex(1) if ($pdf);
+	check_missing(\%map);
+	print "I don't know distro $system_release.\n";
+	print "So, I can't provide you a hint with the install procedure.\n";
+	print "There are likely missing dependencies.\n";
+}
+
+#
+# Common dependencies
+#
+
+sub check_needs()
+{
+	if ($system_release) {
+		print "Checking if the needed tools for $system_release are available\n";
+	} else {
+		print "Checking if the needed tools are present\n";
+	}
+
+	# Check for needed programs/tools
+	check_sphinx();
+	check_perl_module("Pod::Usage", 0);
+	check_program("make", 0);
+	check_program("gcc", 0);
+	check_python_module("sphinx_rtd_theme", 1) if (!$virtualenv);
+	check_program("xelatex", 1) if ($pdf);
+	check_program("dot", 1);
+	check_program("convert", 1);
+	check_program("rsvg-convert", 1) if ($pdf);
+
+	check_distros();
+
+	if ($need_symlink) {
+		printf "\tsudo ln -sf %s /usr/bin/sphinx-build\n\n",
+		       which("sphinx-build-3");
+	}
+	if ($need_sphinx) {
+		my $activate = "$virtenv_dir/bin/activate";
+		if (-e "$ENV{'PWD'}/$activate") {
+			printf "\nNeed to activate virtualenv with:\n";
+			printf "\t. $activate\n";
+		} else {
+			my $virtualenv = findprog("virtualenv-3");
+			$virtualenv = findprog("virtualenv-3.5") if (!$virtualenv);
+			$virtualenv = findprog("virtualenv") if (!$virtualenv);
+			$virtualenv = "virtualenv" if (!$virtualenv);
+
+			printf "\t$virtualenv $virtenv_dir\n";
+			printf "\t. $activate\n";
+			printf "\tpip install -r $requirement_file\n";
+			$need++;
+		}
+	}
+	printf "\n";
+
+	print "All optional dependenties are met.\n" if (!$optional);
+
+	if ($need == 1) {
+		die "Can't build as $need mandatory dependency is missing";
+	} elsif ($need) {
+		die "Can't build as $need mandatory dependencies are missing";
+	}
+
+	print "Needed package dependencies are met.\n";
+}
+
+#
+# Main
+#
+
+while (@ARGV) {
+	my $arg = shift(@ARGV);
+
+	if ($arg eq "--no-virtualenv") {
+		$virtualenv = 0;
+	} elsif ($arg eq "--no-pdf"){
+		$pdf = 0;
+	} else {
+		print "Usage:\n\t$0 <--no-virtualenv> <--no-pdf>\n\n";
+		exit -1;
+	}
+}
+
+#
+# Determine the system type. There's no standard unique way that would
+# work with all distros with a minimal package install. So, several
+# methods are used here.
+#
+# By default, it will use lsb_release function. If not available, it will
+# fail back to reading the known different places where the distro name
+# is stored
+#
+
+$system_release = qx(lsb_release -d) if which("lsb_release");
+$system_release =~ s/Description:\s*// if ($system_release);
+$system_release = catcheck("/etc/system-release") if !$system_release;
+$system_release = catcheck("/etc/redhat-release") if !$system_release;
+$system_release = catcheck("/etc/lsb-release") if !$system_release;
+$system_release = catcheck("/etc/gentoo-release") if !$system_release;
+$system_release = catcheck("/etc/issue") if !$system_release;
+$system_release =~ s/\s+$//;
+
+check_needs;