OpenCloudOS-Kernel/Documentation/kbuild/gcc-plugins.rst

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=========================
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
GCC plugin infrastructure
=========================
Introduction
============
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
GCC plugins are loadable modules that provide extra features to the
compiler [1]_. They are useful for runtime instrumentation and static analysis.
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
We can analyse, change and add further code during compilation via
callbacks [2]_, GIMPLE [3]_, IPA [4]_ and RTL passes [5]_.
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
doc: gcc-plugins: update gcc-plugins.rst This document was written a long time ago. Update it. [1] Drop the version information The range of the supported GCC versions are always changing. The current minimal GCC version is 4.9, and commit 1e860048c53e ("gcc-plugins: simplify GCC plugin-dev capability test") removed the old code accordingly. We do not need to mention specific version ranges like "all gcc versions from 4.5 to 6.0" since we forget to update the documentation when we raise the minimal compiler version. [2] Drop the C compiler statements Since commit 77342a02ff6e ("gcc-plugins: drop support for GCC <= 4.7") the GCC plugin infrastructure only supports g++. [3] Drop supported architectures As of v5.11-rc4, the infrastructure supports more architectures; arm, arm64, mips, powerpc, riscv, s390, um, and x86. (just grep "select HAVE_GCC_PLUGINS") Again, we miss to update this document when a new architecture is supported. Let's just say "only some architectures". [4] Update the apt-get example We are now discussing to bump the minimal version to GCC 5. The GCC 4.9 support will be removed sooner or later. Change the package example to gcc-10-plugin-dev while we are here. [5] Update the build target Since commit ce2fd53a10c7 ("kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile"), "make gcc-plugins" is not supported. "make scripts" builds all the enabled plugins, including some other tools. [6] Update the steps for adding a new plugin At first, all CONFIG options for GCC plugins were located in arch/Kconfig. After commit 45332b1bdfdc ("gcc-plugins: split out Kconfig entries to scripts/gcc-plugins/Kconfig"), scripts/gcc-plugins/Kconfig became the central place to collect plugin CONFIG options. In my understanding, this requirement no longer exists because commit 9f671e58159a ("security: Create "kernel hardening" config area") moved some of plugin CONFIG options to another file. Find an appropriate place to add the new CONFIG. The sub-directory support was never used by anyone, and removed by commit c17d6179ad5a ("gcc-plugins: remove unused GCC_PLUGIN_SUBDIR"). Remove the useless $(src)/ prefix. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-01-23 21:33:33 +08:00
The GCC plugin infrastructure of the kernel supports building out-of-tree
modules, cross-compilation and building in a separate directory.
Plugin source files have to be compilable by a C++ compiler.
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
doc: gcc-plugins: update gcc-plugins.rst This document was written a long time ago. Update it. [1] Drop the version information The range of the supported GCC versions are always changing. The current minimal GCC version is 4.9, and commit 1e860048c53e ("gcc-plugins: simplify GCC plugin-dev capability test") removed the old code accordingly. We do not need to mention specific version ranges like "all gcc versions from 4.5 to 6.0" since we forget to update the documentation when we raise the minimal compiler version. [2] Drop the C compiler statements Since commit 77342a02ff6e ("gcc-plugins: drop support for GCC <= 4.7") the GCC plugin infrastructure only supports g++. [3] Drop supported architectures As of v5.11-rc4, the infrastructure supports more architectures; arm, arm64, mips, powerpc, riscv, s390, um, and x86. (just grep "select HAVE_GCC_PLUGINS") Again, we miss to update this document when a new architecture is supported. Let's just say "only some architectures". [4] Update the apt-get example We are now discussing to bump the minimal version to GCC 5. The GCC 4.9 support will be removed sooner or later. Change the package example to gcc-10-plugin-dev while we are here. [5] Update the build target Since commit ce2fd53a10c7 ("kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile"), "make gcc-plugins" is not supported. "make scripts" builds all the enabled plugins, including some other tools. [6] Update the steps for adding a new plugin At first, all CONFIG options for GCC plugins were located in arch/Kconfig. After commit 45332b1bdfdc ("gcc-plugins: split out Kconfig entries to scripts/gcc-plugins/Kconfig"), scripts/gcc-plugins/Kconfig became the central place to collect plugin CONFIG options. In my understanding, this requirement no longer exists because commit 9f671e58159a ("security: Create "kernel hardening" config area") moved some of plugin CONFIG options to another file. Find an appropriate place to add the new CONFIG. The sub-directory support was never used by anyone, and removed by commit c17d6179ad5a ("gcc-plugins: remove unused GCC_PLUGIN_SUBDIR"). Remove the useless $(src)/ prefix. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-01-23 21:33:33 +08:00
Currently the GCC plugin infrastructure supports only some architectures.
Grep "select HAVE_GCC_PLUGINS" to find out which architectures support
GCC plugins.
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
This infrastructure was ported from grsecurity [6]_ and PaX [7]_.
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
--
.. [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
=====
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
**$(src)/scripts/gcc-plugins**
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
This is the directory of the GCC plugins.
**$(src)/scripts/gcc-plugins/gcc-common.h**
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
This is a compatibility header for GCC plugins.
It should be always included instead of individual gcc headers.
**$(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**
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
These headers automatically generate the registration structures for
doc: gcc-plugins: update gcc-plugins.rst This document was written a long time ago. Update it. [1] Drop the version information The range of the supported GCC versions are always changing. The current minimal GCC version is 4.9, and commit 1e860048c53e ("gcc-plugins: simplify GCC plugin-dev capability test") removed the old code accordingly. We do not need to mention specific version ranges like "all gcc versions from 4.5 to 6.0" since we forget to update the documentation when we raise the minimal compiler version. [2] Drop the C compiler statements Since commit 77342a02ff6e ("gcc-plugins: drop support for GCC <= 4.7") the GCC plugin infrastructure only supports g++. [3] Drop supported architectures As of v5.11-rc4, the infrastructure supports more architectures; arm, arm64, mips, powerpc, riscv, s390, um, and x86. (just grep "select HAVE_GCC_PLUGINS") Again, we miss to update this document when a new architecture is supported. Let's just say "only some architectures". [4] Update the apt-get example We are now discussing to bump the minimal version to GCC 5. The GCC 4.9 support will be removed sooner or later. Change the package example to gcc-10-plugin-dev while we are here. [5] Update the build target Since commit ce2fd53a10c7 ("kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile"), "make gcc-plugins" is not supported. "make scripts" builds all the enabled plugins, including some other tools. [6] Update the steps for adding a new plugin At first, all CONFIG options for GCC plugins were located in arch/Kconfig. After commit 45332b1bdfdc ("gcc-plugins: split out Kconfig entries to scripts/gcc-plugins/Kconfig"), scripts/gcc-plugins/Kconfig became the central place to collect plugin CONFIG options. In my understanding, this requirement no longer exists because commit 9f671e58159a ("security: Create "kernel hardening" config area") moved some of plugin CONFIG options to another file. Find an appropriate place to add the new CONFIG. The sub-directory support was never used by anyone, and removed by commit c17d6179ad5a ("gcc-plugins: remove unused GCC_PLUGIN_SUBDIR"). Remove the useless $(src)/ prefix. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-01-23 21:33:33 +08:00
GIMPLE, SIMPLE_IPA, IPA and RTL passes.
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
They should be preferred to creating the structures by hand.
Usage
=====
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
You must install the gcc plugin headers for your gcc version,
doc: gcc-plugins: update gcc-plugins.rst This document was written a long time ago. Update it. [1] Drop the version information The range of the supported GCC versions are always changing. The current minimal GCC version is 4.9, and commit 1e860048c53e ("gcc-plugins: simplify GCC plugin-dev capability test") removed the old code accordingly. We do not need to mention specific version ranges like "all gcc versions from 4.5 to 6.0" since we forget to update the documentation when we raise the minimal compiler version. [2] Drop the C compiler statements Since commit 77342a02ff6e ("gcc-plugins: drop support for GCC <= 4.7") the GCC plugin infrastructure only supports g++. [3] Drop supported architectures As of v5.11-rc4, the infrastructure supports more architectures; arm, arm64, mips, powerpc, riscv, s390, um, and x86. (just grep "select HAVE_GCC_PLUGINS") Again, we miss to update this document when a new architecture is supported. Let's just say "only some architectures". [4] Update the apt-get example We are now discussing to bump the minimal version to GCC 5. The GCC 4.9 support will be removed sooner or later. Change the package example to gcc-10-plugin-dev while we are here. [5] Update the build target Since commit ce2fd53a10c7 ("kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile"), "make gcc-plugins" is not supported. "make scripts" builds all the enabled plugins, including some other tools. [6] Update the steps for adding a new plugin At first, all CONFIG options for GCC plugins were located in arch/Kconfig. After commit 45332b1bdfdc ("gcc-plugins: split out Kconfig entries to scripts/gcc-plugins/Kconfig"), scripts/gcc-plugins/Kconfig became the central place to collect plugin CONFIG options. In my understanding, this requirement no longer exists because commit 9f671e58159a ("security: Create "kernel hardening" config area") moved some of plugin CONFIG options to another file. Find an appropriate place to add the new CONFIG. The sub-directory support was never used by anyone, and removed by commit c17d6179ad5a ("gcc-plugins: remove unused GCC_PLUGIN_SUBDIR"). Remove the useless $(src)/ prefix. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-01-23 21:33:33 +08:00
e.g., on Ubuntu for gcc-10::
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
doc: gcc-plugins: update gcc-plugins.rst This document was written a long time ago. Update it. [1] Drop the version information The range of the supported GCC versions are always changing. The current minimal GCC version is 4.9, and commit 1e860048c53e ("gcc-plugins: simplify GCC plugin-dev capability test") removed the old code accordingly. We do not need to mention specific version ranges like "all gcc versions from 4.5 to 6.0" since we forget to update the documentation when we raise the minimal compiler version. [2] Drop the C compiler statements Since commit 77342a02ff6e ("gcc-plugins: drop support for GCC <= 4.7") the GCC plugin infrastructure only supports g++. [3] Drop supported architectures As of v5.11-rc4, the infrastructure supports more architectures; arm, arm64, mips, powerpc, riscv, s390, um, and x86. (just grep "select HAVE_GCC_PLUGINS") Again, we miss to update this document when a new architecture is supported. Let's just say "only some architectures". [4] Update the apt-get example We are now discussing to bump the minimal version to GCC 5. The GCC 4.9 support will be removed sooner or later. Change the package example to gcc-10-plugin-dev while we are here. [5] Update the build target Since commit ce2fd53a10c7 ("kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile"), "make gcc-plugins" is not supported. "make scripts" builds all the enabled plugins, including some other tools. [6] Update the steps for adding a new plugin At first, all CONFIG options for GCC plugins were located in arch/Kconfig. After commit 45332b1bdfdc ("gcc-plugins: split out Kconfig entries to scripts/gcc-plugins/Kconfig"), scripts/gcc-plugins/Kconfig became the central place to collect plugin CONFIG options. In my understanding, this requirement no longer exists because commit 9f671e58159a ("security: Create "kernel hardening" config area") moved some of plugin CONFIG options to another file. Find an appropriate place to add the new CONFIG. The sub-directory support was never used by anyone, and removed by commit c17d6179ad5a ("gcc-plugins: remove unused GCC_PLUGIN_SUBDIR"). Remove the useless $(src)/ prefix. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-01-23 21:33:33 +08:00
apt-get install gcc-10-plugin-dev
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
Or on Fedora::
dnf install gcc-plugin-devel
doc: gcc-plugins: update gcc-plugins.rst This document was written a long time ago. Update it. [1] Drop the version information The range of the supported GCC versions are always changing. The current minimal GCC version is 4.9, and commit 1e860048c53e ("gcc-plugins: simplify GCC plugin-dev capability test") removed the old code accordingly. We do not need to mention specific version ranges like "all gcc versions from 4.5 to 6.0" since we forget to update the documentation when we raise the minimal compiler version. [2] Drop the C compiler statements Since commit 77342a02ff6e ("gcc-plugins: drop support for GCC <= 4.7") the GCC plugin infrastructure only supports g++. [3] Drop supported architectures As of v5.11-rc4, the infrastructure supports more architectures; arm, arm64, mips, powerpc, riscv, s390, um, and x86. (just grep "select HAVE_GCC_PLUGINS") Again, we miss to update this document when a new architecture is supported. Let's just say "only some architectures". [4] Update the apt-get example We are now discussing to bump the minimal version to GCC 5. The GCC 4.9 support will be removed sooner or later. Change the package example to gcc-10-plugin-dev while we are here. [5] Update the build target Since commit ce2fd53a10c7 ("kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile"), "make gcc-plugins" is not supported. "make scripts" builds all the enabled plugins, including some other tools. [6] Update the steps for adding a new plugin At first, all CONFIG options for GCC plugins were located in arch/Kconfig. After commit 45332b1bdfdc ("gcc-plugins: split out Kconfig entries to scripts/gcc-plugins/Kconfig"), scripts/gcc-plugins/Kconfig became the central place to collect plugin CONFIG options. In my understanding, this requirement no longer exists because commit 9f671e58159a ("security: Create "kernel hardening" config area") moved some of plugin CONFIG options to another file. Find an appropriate place to add the new CONFIG. The sub-directory support was never used by anyone, and removed by commit c17d6179ad5a ("gcc-plugins: remove unused GCC_PLUGIN_SUBDIR"). Remove the useless $(src)/ prefix. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-01-23 21:33:33 +08:00
Enable the GCC plugin infrastructure and some plugin(s) you want to use
in the kernel config::
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
doc: gcc-plugins: update gcc-plugins.rst This document was written a long time ago. Update it. [1] Drop the version information The range of the supported GCC versions are always changing. The current minimal GCC version is 4.9, and commit 1e860048c53e ("gcc-plugins: simplify GCC plugin-dev capability test") removed the old code accordingly. We do not need to mention specific version ranges like "all gcc versions from 4.5 to 6.0" since we forget to update the documentation when we raise the minimal compiler version. [2] Drop the C compiler statements Since commit 77342a02ff6e ("gcc-plugins: drop support for GCC <= 4.7") the GCC plugin infrastructure only supports g++. [3] Drop supported architectures As of v5.11-rc4, the infrastructure supports more architectures; arm, arm64, mips, powerpc, riscv, s390, um, and x86. (just grep "select HAVE_GCC_PLUGINS") Again, we miss to update this document when a new architecture is supported. Let's just say "only some architectures". [4] Update the apt-get example We are now discussing to bump the minimal version to GCC 5. The GCC 4.9 support will be removed sooner or later. Change the package example to gcc-10-plugin-dev while we are here. [5] Update the build target Since commit ce2fd53a10c7 ("kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile"), "make gcc-plugins" is not supported. "make scripts" builds all the enabled plugins, including some other tools. [6] Update the steps for adding a new plugin At first, all CONFIG options for GCC plugins were located in arch/Kconfig. After commit 45332b1bdfdc ("gcc-plugins: split out Kconfig entries to scripts/gcc-plugins/Kconfig"), scripts/gcc-plugins/Kconfig became the central place to collect plugin CONFIG options. In my understanding, this requirement no longer exists because commit 9f671e58159a ("security: Create "kernel hardening" config area") moved some of plugin CONFIG options to another file. Find an appropriate place to add the new CONFIG. The sub-directory support was never used by anyone, and removed by commit c17d6179ad5a ("gcc-plugins: remove unused GCC_PLUGIN_SUBDIR"). Remove the useless $(src)/ prefix. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-01-23 21:33:33 +08:00
CONFIG_GCC_PLUGINS=y
CONFIG_GCC_PLUGIN_CYC_COMPLEXITY=y
CONFIG_GCC_PLUGIN_LATENT_ENTROPY=y
...
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
doc: gcc-plugins: update gcc-plugins.rst This document was written a long time ago. Update it. [1] Drop the version information The range of the supported GCC versions are always changing. The current minimal GCC version is 4.9, and commit 1e860048c53e ("gcc-plugins: simplify GCC plugin-dev capability test") removed the old code accordingly. We do not need to mention specific version ranges like "all gcc versions from 4.5 to 6.0" since we forget to update the documentation when we raise the minimal compiler version. [2] Drop the C compiler statements Since commit 77342a02ff6e ("gcc-plugins: drop support for GCC <= 4.7") the GCC plugin infrastructure only supports g++. [3] Drop supported architectures As of v5.11-rc4, the infrastructure supports more architectures; arm, arm64, mips, powerpc, riscv, s390, um, and x86. (just grep "select HAVE_GCC_PLUGINS") Again, we miss to update this document when a new architecture is supported. Let's just say "only some architectures". [4] Update the apt-get example We are now discussing to bump the minimal version to GCC 5. The GCC 4.9 support will be removed sooner or later. Change the package example to gcc-10-plugin-dev while we are here. [5] Update the build target Since commit ce2fd53a10c7 ("kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile"), "make gcc-plugins" is not supported. "make scripts" builds all the enabled plugins, including some other tools. [6] Update the steps for adding a new plugin At first, all CONFIG options for GCC plugins were located in arch/Kconfig. After commit 45332b1bdfdc ("gcc-plugins: split out Kconfig entries to scripts/gcc-plugins/Kconfig"), scripts/gcc-plugins/Kconfig became the central place to collect plugin CONFIG options. In my understanding, this requirement no longer exists because commit 9f671e58159a ("security: Create "kernel hardening" config area") moved some of plugin CONFIG options to another file. Find an appropriate place to add the new CONFIG. The sub-directory support was never used by anyone, and removed by commit c17d6179ad5a ("gcc-plugins: remove unused GCC_PLUGIN_SUBDIR"). Remove the useless $(src)/ prefix. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-01-23 21:33:33 +08:00
To compile the minimum tool set including the plugin(s)::
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
doc: gcc-plugins: update gcc-plugins.rst This document was written a long time ago. Update it. [1] Drop the version information The range of the supported GCC versions are always changing. The current minimal GCC version is 4.9, and commit 1e860048c53e ("gcc-plugins: simplify GCC plugin-dev capability test") removed the old code accordingly. We do not need to mention specific version ranges like "all gcc versions from 4.5 to 6.0" since we forget to update the documentation when we raise the minimal compiler version. [2] Drop the C compiler statements Since commit 77342a02ff6e ("gcc-plugins: drop support for GCC <= 4.7") the GCC plugin infrastructure only supports g++. [3] Drop supported architectures As of v5.11-rc4, the infrastructure supports more architectures; arm, arm64, mips, powerpc, riscv, s390, um, and x86. (just grep "select HAVE_GCC_PLUGINS") Again, we miss to update this document when a new architecture is supported. Let's just say "only some architectures". [4] Update the apt-get example We are now discussing to bump the minimal version to GCC 5. The GCC 4.9 support will be removed sooner or later. Change the package example to gcc-10-plugin-dev while we are here. [5] Update the build target Since commit ce2fd53a10c7 ("kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile"), "make gcc-plugins" is not supported. "make scripts" builds all the enabled plugins, including some other tools. [6] Update the steps for adding a new plugin At first, all CONFIG options for GCC plugins were located in arch/Kconfig. After commit 45332b1bdfdc ("gcc-plugins: split out Kconfig entries to scripts/gcc-plugins/Kconfig"), scripts/gcc-plugins/Kconfig became the central place to collect plugin CONFIG options. In my understanding, this requirement no longer exists because commit 9f671e58159a ("security: Create "kernel hardening" config area") moved some of plugin CONFIG options to another file. Find an appropriate place to add the new CONFIG. The sub-directory support was never used by anyone, and removed by commit c17d6179ad5a ("gcc-plugins: remove unused GCC_PLUGIN_SUBDIR"). Remove the useless $(src)/ prefix. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-01-23 21:33:33 +08:00
make scripts
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
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
==============================
doc: gcc-plugins: update gcc-plugins.rst This document was written a long time ago. Update it. [1] Drop the version information The range of the supported GCC versions are always changing. The current minimal GCC version is 4.9, and commit 1e860048c53e ("gcc-plugins: simplify GCC plugin-dev capability test") removed the old code accordingly. We do not need to mention specific version ranges like "all gcc versions from 4.5 to 6.0" since we forget to update the documentation when we raise the minimal compiler version. [2] Drop the C compiler statements Since commit 77342a02ff6e ("gcc-plugins: drop support for GCC <= 4.7") the GCC plugin infrastructure only supports g++. [3] Drop supported architectures As of v5.11-rc4, the infrastructure supports more architectures; arm, arm64, mips, powerpc, riscv, s390, um, and x86. (just grep "select HAVE_GCC_PLUGINS") Again, we miss to update this document when a new architecture is supported. Let's just say "only some architectures". [4] Update the apt-get example We are now discussing to bump the minimal version to GCC 5. The GCC 4.9 support will be removed sooner or later. Change the package example to gcc-10-plugin-dev while we are here. [5] Update the build target Since commit ce2fd53a10c7 ("kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile"), "make gcc-plugins" is not supported. "make scripts" builds all the enabled plugins, including some other tools. [6] Update the steps for adding a new plugin At first, all CONFIG options for GCC plugins were located in arch/Kconfig. After commit 45332b1bdfdc ("gcc-plugins: split out Kconfig entries to scripts/gcc-plugins/Kconfig"), scripts/gcc-plugins/Kconfig became the central place to collect plugin CONFIG options. In my understanding, this requirement no longer exists because commit 9f671e58159a ("security: Create "kernel hardening" config area") moved some of plugin CONFIG options to another file. Find an appropriate place to add the new CONFIG. The sub-directory support was never used by anyone, and removed by commit c17d6179ad5a ("gcc-plugins: remove unused GCC_PLUGIN_SUBDIR"). Remove the useless $(src)/ prefix. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-01-23 21:33:33 +08:00
The GCC plugins are in scripts/gcc-plugins/. You need to put plugin source files
right under scripts/gcc-plugins/. Creating subdirectories is not supported.
It must be added to scripts/gcc-plugins/Makefile, scripts/Makefile.gcc-plugins
and a relevant Kconfig file.
GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-24 06:09:38 +08:00
See the cyc_complexity_plugin.c (CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) GCC plugin.