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-rw-r--r--Documentation/kbuild/gcc-plugins.rst97
-rw-r--r--Documentation/kbuild/index.rst1
-rw-r--r--Documentation/kbuild/kbuild.rst2
-rw-r--r--Documentation/kbuild/kconfig-macro-language.rst2
-rw-r--r--Documentation/kbuild/makefiles.rst6
-rw-r--r--Documentation/kbuild/modules.rst4
6 files changed, 105 insertions, 7 deletions
diff --git a/Documentation/kbuild/gcc-plugins.rst b/Documentation/kbuild/gcc-plugins.rst
new file mode 100644
index 000000000000..4b1c10f88e30
--- /dev/null
+++ b/Documentation/kbuild/gcc-plugins.rst
@@ -0,0 +1,97 @@
+=========================
+GCC plugin infrastructure
+=========================
+
+
+Introduction
+============
+
+GCC plugins are loadable modules that provide extra features to the
+compiler [1]_. They are useful for runtime instrumentation and static analysis.
+We can analyse, change and add further code during compilation via
+callbacks [2]_, GIMPLE [3]_, IPA [4]_ and RTL passes [5]_.
+
+The GCC plugin infrastructure of the kernel supports all gcc versions from
+4.5 to 6.0, building out-of-tree modules, cross-compilation and building in a
+separate directory.
+Plugin source files have to be compilable by both a C and a C++ compiler as well
+because gcc versions 4.5 and 4.6 are compiled by a C compiler,
+gcc-4.7 can be compiled by a C or a C++ compiler,
+and versions 4.8+ can only be compiled by a C++ compiler.
+
+Currently the GCC plugin infrastructure supports only the x86, arm, arm64 and
+powerpc architectures.
+
+This infrastructure was ported from grsecurity [6]_ and PaX [7]_.
+
+--
+
+.. [1] https://gcc.gnu.org/onlinedocs/gccint/Plugins.html
+.. [2] https://gcc.gnu.org/onlinedocs/gccint/Plugin-API.html#Plugin-API
+.. [3] https://gcc.gnu.org/onlinedocs/gccint/GIMPLE.html
+.. [4] https://gcc.gnu.org/onlinedocs/gccint/IPA.html
+.. [5] https://gcc.gnu.org/onlinedocs/gccint/RTL.html
+.. [6] https://grsecurity.net/
+.. [7] https://pax.grsecurity.net/
+
+
+Files
+=====
+
+**$(src)/scripts/gcc-plugins**
+
+ This is the directory of the GCC plugins.
+
+**$(src)/scripts/gcc-plugins/gcc-common.h**
+
+ This is a compatibility header for GCC plugins.
+ It should be always included instead of individual gcc headers.
+
+**$(src)/scripts/gcc-plugin.sh**
+
+ This script checks the availability of the included headers in
+ gcc-common.h and chooses the proper host compiler to build the plugins
+ (gcc-4.7 can be built by either gcc or g++).
+
+**$(src)/scripts/gcc-plugins/gcc-generate-gimple-pass.h,
+$(src)/scripts/gcc-plugins/gcc-generate-ipa-pass.h,
+$(src)/scripts/gcc-plugins/gcc-generate-simple_ipa-pass.h,
+$(src)/scripts/gcc-plugins/gcc-generate-rtl-pass.h**
+
+ These headers automatically generate the registration structures for
+ GIMPLE, SIMPLE_IPA, IPA and RTL passes. They support all gcc versions
+ from 4.5 to 6.0.
+ They should be preferred to creating the structures by hand.
+
+
+Usage
+=====
+
+You must install the gcc plugin headers for your gcc version,
+e.g., on Ubuntu for gcc-4.9::
+
+ apt-get install gcc-4.9-plugin-dev
+
+Or on Fedora::
+
+ dnf install gcc-plugin-devel
+
+Enable a GCC plugin based feature in the kernel config::
+
+ CONFIG_GCC_PLUGIN_CYC_COMPLEXITY = y
+
+To compile only the plugin(s)::
+
+ make gcc-plugins
+
+or just run the kernel make and compile the whole kernel with
+the cyclomatic complexity GCC plugin.
+
+
+4. How to add a new GCC plugin
+==============================
+
+The GCC plugins are in $(src)/scripts/gcc-plugins/. You can use a file or a directory
+here. It must be added to $(src)/scripts/gcc-plugins/Makefile,
+$(src)/scripts/Makefile.gcc-plugins and $(src)/arch/Kconfig.
+See the cyc_complexity_plugin.c (CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) GCC plugin.
diff --git a/Documentation/kbuild/index.rst b/Documentation/kbuild/index.rst
index 0f144fad99a6..82daf2efcb73 100644
--- a/Documentation/kbuild/index.rst
+++ b/Documentation/kbuild/index.rst
@@ -19,6 +19,7 @@ Kernel Build System
issues
reproducible-builds
+ gcc-plugins
.. only:: subproject and html
diff --git a/Documentation/kbuild/kbuild.rst b/Documentation/kbuild/kbuild.rst
index f1e5dce86af7..510f38d7e78a 100644
--- a/Documentation/kbuild/kbuild.rst
+++ b/Documentation/kbuild/kbuild.rst
@@ -237,7 +237,7 @@ This is solely useful to speed up test compiles.
KBUILD_EXTRA_SYMBOLS
--------------------
For modules that use symbols from other modules.
-See more details in modules.txt.
+See more details in modules.rst.
ALLSOURCE_ARCHS
---------------
diff --git a/Documentation/kbuild/kconfig-macro-language.rst b/Documentation/kbuild/kconfig-macro-language.rst
index 35b3263b7e40..8b413ef9603d 100644
--- a/Documentation/kbuild/kconfig-macro-language.rst
+++ b/Documentation/kbuild/kconfig-macro-language.rst
@@ -44,7 +44,7 @@ intermediate::
def_bool y
Then, Kconfig moves onto the evaluation stage to resolve inter-symbol
-dependency as explained in kconfig-language.txt.
+dependency as explained in kconfig-language.rst.
Variables
diff --git a/Documentation/kbuild/makefiles.rst b/Documentation/kbuild/makefiles.rst
index 6bc126a14b3d..04d5c01a2e99 100644
--- a/Documentation/kbuild/makefiles.rst
+++ b/Documentation/kbuild/makefiles.rst
@@ -924,7 +924,7 @@ When kbuild executes, the following steps are followed (roughly):
$(KBUILD_AFLAGS_MODULE) is used to add arch-specific options that
are used for assembler.
- From commandline AFLAGS_MODULE shall be used (see kbuild.txt).
+ From commandline AFLAGS_MODULE shall be used (see kbuild.rst).
KBUILD_CFLAGS_KERNEL
$(CC) options specific for built-in
@@ -937,7 +937,7 @@ When kbuild executes, the following steps are followed (roughly):
$(KBUILD_CFLAGS_MODULE) is used to add arch-specific options that
are used for $(CC).
- From commandline CFLAGS_MODULE shall be used (see kbuild.txt).
+ From commandline CFLAGS_MODULE shall be used (see kbuild.rst).
KBUILD_LDFLAGS_MODULE
Options for $(LD) when linking modules
@@ -945,7 +945,7 @@ When kbuild executes, the following steps are followed (roughly):
$(KBUILD_LDFLAGS_MODULE) is used to add arch-specific options
used when linking modules. This is often a linker script.
- From commandline LDFLAGS_MODULE shall be used (see kbuild.txt).
+ From commandline LDFLAGS_MODULE shall be used (see kbuild.rst).
KBUILD_LDS
diff --git a/Documentation/kbuild/modules.rst b/Documentation/kbuild/modules.rst
index 69fa48ee93d6..e0b45a257f21 100644
--- a/Documentation/kbuild/modules.rst
+++ b/Documentation/kbuild/modules.rst
@@ -470,9 +470,9 @@ build.
The syntax of the Module.symvers file is::
- <CRC> <Symbol> <Namespace> <Module> <Export Type>
+ <CRC> <Symbol> <Module> <Export Type> <Namespace>
- 0xe1cc2a05 usb_stor_suspend USB_STORAGE drivers/usb/storage/usb-storage EXPORT_SYMBOL_GPL
+ 0xe1cc2a05 usb_stor_suspend drivers/usb/storage/usb-storage EXPORT_SYMBOL_GPL USB_STORAGE
The fields are separated by tabs and values may be empty (e.g.
if no namespace is defined for an exported symbol).