Merge tag 'gcc-plugin-cleanup-v4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull gcc plugin cleanups from Kees Cook:

 - Kconfig and Makefile clean-ups (Masahiro Yamada, Kees Cook)

 - gcc-common.h definition clean-ups (Alexander Popov)

* tag 'gcc-plugin-cleanup-v4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  gcc-plugins: Clean up the cgraph_create_edge* macros
  gcc-plugins: Regularize Makefile.gcc-plugins
  gcc-plugins: split out Kconfig entries to scripts/gcc-plugins/Kconfig
  gcc-plugins: remove unused GCC_PLUGIN_SUBDIR

5 files changed, 184 insertions, 172 deletions

diff --git a/arch/Kconfig b/arch/Kconfig
index d1f2ed462ac8..8543bc3c21fe 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -408,150 +408,6 @@ config SECCOMP_FILTER
 
           See Documentation/userspace-api/seccomp_filter.rst for details.
 
-preferred-plugin-hostcc := $(if-success,[ $(gcc-version) -ge 40800 ],$(HOSTCXX),$(HOSTCC))
-
-config PLUGIN_HOSTCC
-        string
-        default "$(shell,$(srctree)/scripts/gcc-plugin.sh "$(preferred-plugin-hostcc)" "$(HOSTCXX)" "$(CC)")"
-        help
-          Host compiler used to build GCC plugins.  This can be $(HOSTCXX),
-          $(HOSTCC), or a null string if GCC plugin is unsupported.
-
-config HAVE_GCC_PLUGINS
-        bool
-        help
-          An arch should select this symbol if it supports building with
-          GCC plugins.
-
-menuconfig GCC_PLUGINS
-        bool "GCC plugins"
-        depends on HAVE_GCC_PLUGINS
-        depends on PLUGIN_HOSTCC != ""
-        help
-          GCC plugins are loadable modules that provide extra features to the
-          compiler. They are useful for runtime instrumentation and static analysis.
-
-          See Documentation/gcc-plugins.txt for details.
-
-config GCC_PLUGIN_CYC_COMPLEXITY
-        bool "Compute the cyclomatic complexity of a function" if EXPERT
-        depends on GCC_PLUGINS
-        depends on !COMPILE_TEST        # too noisy
-        help
-          The complexity M of a function's control flow graph is defined as:
-           M = E - N + 2P
-          where
-
-          E = the number of edges
-          N = the number of nodes
-          P = the number of connected components (exit nodes).
-
-          Enabling this plugin reports the complexity to stderr during the
-          build. It mainly serves as a simple example of how to create a
-          gcc plugin for the kernel.
-
-config GCC_PLUGIN_SANCOV
-        bool
-        depends on GCC_PLUGINS
-        help
-          This plugin inserts a __sanitizer_cov_trace_pc() call at the start of
-          basic blocks. It supports all gcc versions with plugin support (from
-          gcc-4.5 on). It is based on the commit "Add fuzzing coverage support"
-          by Dmitry Vyukov <dvyukov@google.com>.
-
-config GCC_PLUGIN_LATENT_ENTROPY
-        bool "Generate some entropy during boot and runtime"
-        depends on GCC_PLUGINS
-        help
-          By saying Y here the kernel will instrument some kernel code to
-          extract some entropy from both original and artificially created
-          program state.  This will help especially embedded systems where
-          there is little 'natural' source of entropy normally.  The cost
-          is some slowdown of the boot process (about 0.5%) and fork and
-          irq processing.
-
-          Note that entropy extracted this way is not cryptographically
-          secure!
-
-          This plugin was ported from grsecurity/PaX. More information at:
-           * https://grsecurity.net/
-           * https://pax.grsecurity.net/
-
-config GCC_PLUGIN_STRUCTLEAK
-        bool "Force initialization of variables containing userspace addresses"
-        depends on GCC_PLUGINS
-        # Currently STRUCTLEAK inserts initialization out of live scope of
-        # variables from KASAN point of view. This leads to KASAN false
-        # positive reports. Prohibit this combination for now.
-        depends on !KASAN_EXTRA
-        help
-          This plugin zero-initializes any structures containing a
-          __user attribute. This can prevent some classes of information
-          exposures.
-
-          This plugin was ported from grsecurity/PaX. More information at:
-           * https://grsecurity.net/
-           * https://pax.grsecurity.net/
-
-config GCC_PLUGIN_STRUCTLEAK_BYREF_ALL
-        bool "Force initialize all struct type variables passed by reference"
-        depends on GCC_PLUGIN_STRUCTLEAK
-        depends on !COMPILE_TEST
-        help
-          Zero initialize any struct type local variable that may be passed by
-          reference without having been initialized.
-
-config GCC_PLUGIN_STRUCTLEAK_VERBOSE
-        bool "Report forcefully initialized variables"
-        depends on GCC_PLUGIN_STRUCTLEAK
-        depends on !COMPILE_TEST        # too noisy
-        help
-          This option will cause a warning to be printed each time the
-          structleak plugin finds a variable it thinks needs to be
-          initialized. Since not all existing initializers are detected
-          by the plugin, this can produce false positive warnings.
-
-config GCC_PLUGIN_RANDSTRUCT
-        bool "Randomize layout of sensitive kernel structures"
-        depends on GCC_PLUGINS
-        select MODVERSIONS if MODULES
-        help
-          If you say Y here, the layouts of structures that are entirely
-          function pointers (and have not been manually annotated with
-          __no_randomize_layout), or structures that have been explicitly
-          marked with __randomize_layout, will be randomized at compile-time.
-          This can introduce the requirement of an additional information
-          exposure vulnerability for exploits targeting these structure
-          types.
-
-          Enabling this feature will introduce some performance impact,
-          slightly increase memory usage, and prevent the use of forensic
-          tools like Volatility against the system (unless the kernel
-          source tree isn't cleaned after kernel installation).
-
-          The seed used for compilation is located at
-          scripts/gcc-plgins/randomize_layout_seed.h.  It remains after
-          a make clean to allow for external modules to be compiled with
-          the existing seed and will be removed by a make mrproper or
-          make distclean.
-
-          Note that the implementation requires gcc 4.7 or newer.
-
-          This plugin was ported from grsecurity/PaX. More information at:
-           * https://grsecurity.net/
-           * https://pax.grsecurity.net/
-
-config GCC_PLUGIN_RANDSTRUCT_PERFORMANCE
-        bool "Use cacheline-aware structure randomization"
-        depends on GCC_PLUGIN_RANDSTRUCT
-        depends on !COMPILE_TEST        # do not reduce test coverage
-        help
-          If you say Y here, the RANDSTRUCT randomization will make a
-          best effort at restricting randomization to cacheline-sized
-          groups of elements.  It will further not randomize bitfields
-          in structures.  This reduces the performance hit of RANDSTRUCT
-          at the cost of weakened randomization.
-
 config HAVE_STACKPROTECTOR
         bool
         help
@@ -975,3 +831,5 @@ config REFCOUNT_FULL
           security flaw exploits.
 
 source "kernel/gcov/Kconfig"
+
+source "scripts/gcc-plugins/Kconfig"
diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins
index c961b9a65d11..0a482f341576 100644
--- a/scripts/Makefile.gcc-plugins
+++ b/scripts/Makefile.gcc-plugins
@@ -1,33 +1,44 @@
 # SPDX-License-Identifier: GPL-2.0
+
 gcc-plugin-$(CONFIG_GCC_PLUGIN_CYC_COMPLEXITY)  += cyc_complexity_plugin.so
 
 gcc-plugin-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY)  += latent_entropy_plugin.so
-gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY)   += -DLATENT_ENTROPY_PLUGIN
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY)           \
+                += -DLATENT_ENTROPY_PLUGIN
 ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY
-    DISABLE_LATENT_ENTROPY_PLUGIN                       += -fplugin-arg-latent_entropy_plugin-disable
+    DISABLE_LATENT_ENTROPY_PLUGIN += -fplugin-arg-latent_entropy_plugin-disable
 endif
+export DISABLE_LATENT_ENTROPY_PLUGIN
 
 gcc-plugin-$(CONFIG_GCC_PLUGIN_SANCOV)          += sancov_plugin.so
+
 gcc-plugin-$(CONFIG_GCC_PLUGIN_STRUCTLEAK)      += structleak_plugin.so
-gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK_VERBOSE)       += -fplugin-arg-structleak_plugin-verbose
-gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL)     += -fplugin-arg-structleak_plugin-byref-all
-gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK)       += -DSTRUCTLEAK_PLUGIN
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK_VERBOSE)       \
+                += -fplugin-arg-structleak_plugin-verbose
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL)     \
+                += -fplugin-arg-structleak_plugin-byref-all
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK)               \
+                += -DSTRUCTLEAK_PLUGIN
 
 gcc-plugin-$(CONFIG_GCC_PLUGIN_RANDSTRUCT)      += randomize_layout_plugin.so
-gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_RANDSTRUCT)       += -DRANDSTRUCT_PLUGIN
-gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_RANDSTRUCT_PERFORMANCE)   += -fplugin-arg-randomize_layout_plugin-performance-mode
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_RANDSTRUCT)               \
+                += -DRANDSTRUCT_PLUGIN
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_RANDSTRUCT_PERFORMANCE)   \
+                += -fplugin-arg-randomize_layout_plugin-performance-mode
 
+# All the plugin CFLAGS are collected here in case a build target needs to