From 5aadfdeb8de001ca04d500586e3b033404c28617 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 28 May 2018 18:22:04 +0900 Subject: kcov: test compiler capability in Kconfig and correct dependency As Documentation/kbuild/kconfig-language.txt notes, 'select' should be be used with care - it forces a lower limit of another symbol, ignoring the dependency. Currently, KCOV can select GCC_PLUGINS even if arch does not select HAVE_GCC_PLUGINS. This could cause the unmet direct dependency. Now that Kconfig can test compiler capability, let's handle this in a more sophisticated way. There are two ways to enable KCOV; use the compiler that natively supports -fsanitize-coverage=trace-pc, or build the SANCOV plugin if the compiler has ability to build GCC plugins. Hence, the correct dependency for KCOV is: depends on CC_HAS_SANCOV_TRACE_PC || GCC_PLUGINS You do not need to build the SANCOV plugin if the compiler already supports -fsanitize-coverage=trace-pc. Hence, the select should be: select GCC_PLUGIN_SANCOV if !CC_HAS_SANCOV_TRACE_PC With this, GCC_PLUGIN_SANCOV is selected only when necessary, so scripts/Makefile.gcc-plugins can be cleaner. I also cleaned up Kconfig and scripts/Makefile.kcov as well. Signed-off-by: Masahiro Yamada Reviewed-by: Kees Cook --- scripts/Makefile.gcc-plugins | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'scripts/Makefile.gcc-plugins') diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins index 7f5c86246138..708c8f6a5717 100644 --- a/scripts/Makefile.gcc-plugins +++ b/scripts/Makefile.gcc-plugins @@ -14,16 +14,12 @@ ifdef CONFIG_GCC_PLUGINS endif ifdef CONFIG_GCC_PLUGIN_SANCOV - ifeq ($(strip $(CFLAGS_KCOV)),) # It is needed because of the gcc-plugin.sh and gcc version checks. gcc-plugin-$(CONFIG_GCC_PLUGIN_SANCOV) += sancov_plugin.so - ifneq ($(PLUGINCC),) - CFLAGS_KCOV := $(SANCOV_PLUGIN) - else + ifeq ($(PLUGINCC),) $(warning warning: cannot use CONFIG_KCOV: -fsanitize-coverage=trace-pc is not supported by compiler) endif - endif endif gcc-plugin-$(CONFIG_GCC_PLUGIN_STRUCTLEAK) += structleak_plugin.so @@ -38,7 +34,7 @@ ifdef CONFIG_GCC_PLUGINS GCC_PLUGINS_CFLAGS := $(strip $(addprefix -fplugin=$(objtree)/scripts/gcc-plugins/, $(gcc-plugin-y)) $(gcc-plugin-cflags-y)) export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN GCC_PLUGIN_SUBDIR - export SANCOV_PLUGIN DISABLE_LATENT_ENTROPY_PLUGIN + export DISABLE_LATENT_ENTROPY_PLUGIN ifneq ($(PLUGINCC),) # SANCOV_PLUGIN can be only in CFLAGS_KCOV because avoid duplication. -- cgit v1.2.3 From 8034c2fb1225979b1cc9b9a12fa8094ca10b4fc3 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 28 May 2018 18:22:05 +0900 Subject: gcc-plugins: move GCC version check for PowerPC to Kconfig For PowerPC, GCC 5.2 is the requirement for GCC plugins. Move the version check to Kconfig so that the GCC plugin menus will be hidden if an older compiler is in use. Signed-off-by: Masahiro Yamada Acked-by: Andrew Donnellan Reviewed-by: Kees Cook --- arch/powerpc/Kconfig | 2 +- scripts/Makefile.gcc-plugins | 8 -------- 2 files changed, 1 insertion(+), 9 deletions(-) (limited to 'scripts/Makefile.gcc-plugins') diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 076fe3094856..737d333d4df2 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -189,7 +189,7 @@ config PPC select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_TRACER - select HAVE_GCC_PLUGINS + select HAVE_GCC_PLUGINS if GCC_VERSION >= 50200 # plugin support on gcc <= 5.1 is buggy on PPC select HAVE_GENERIC_GUP select HAVE_HW_BREAKPOINT if PERF_EVENTS && (PPC_BOOK3S || PPC_8xx) select HAVE_IDE diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins index 708c8f6a5717..32bdf184eced 100644 --- a/scripts/Makefile.gcc-plugins +++ b/scripts/Makefile.gcc-plugins @@ -53,14 +53,6 @@ gcc-plugins-check: FORCE ifdef CONFIG_GCC_PLUGINS ifeq ($(PLUGINCC),) ifneq ($(GCC_PLUGINS_CFLAGS),) - # Various gccs between 4.5 and 5.1 have bugs on powerpc due to missing - # header files. gcc <= 4.6 doesn't work at all, gccs from 4.8 to 5.1 have - # issues with 64-bit targets. - ifeq ($(ARCH),powerpc) - ifeq ($(call cc-ifversion, -le, 0501, y), y) - @echo "Cannot use CONFIG_GCC_PLUGINS: plugin support on gcc <= 5.1 is buggy on powerpc, please upgrade to gcc 5.2 or newer" >&2 && exit 1 - endif - endif ifeq ($(call cc-ifversion, -ge, 0405, y), y) $(Q)$(srctree)/scripts/gcc-plugin.sh --show-error "$(__PLUGINCC)" "$(HOSTCXX)" "$(CC)" || true @echo "Cannot use CONFIG_GCC_PLUGINS: your gcc installation does not support plugins, perhaps the necessary headers are missing?" >&2 && exit 1 -- cgit v1.2.3 From 59f53855babf757ac7be19995670ab884aaf9b71 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 28 May 2018 18:22:06 +0900 Subject: gcc-plugins: test plugin support in Kconfig and clean up Makefile Run scripts/gcc-plugin.sh from Kconfig so that users can enable GCC_PLUGINS only when the compiler supports building plugins. Kconfig defines a new symbol, PLUGIN_HOSTCC. This will contain the compiler (g++ or gcc) used for building plugins, or empty if the plugin can not be supported at all. This allows us to remove all ugly testing in Makefile.gcc-plugins. Signed-off-by: Masahiro Yamada Acked-by: Kees Cook --- arch/Kconfig | 10 ++++++ scripts/Kconfig.include | 3 ++ scripts/Makefile.gcc-plugins | 79 ++++++++++++-------------------------------- scripts/gcc-plugins/Makefile | 1 + 4 files changed, 36 insertions(+), 57 deletions(-) (limited to 'scripts/Makefile.gcc-plugins') diff --git a/arch/Kconfig b/arch/Kconfig index 2c7c3cf8adfc..e4a47d640a87 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -398,6 +398,15 @@ config SECCOMP_FILTER See Documentation/prctl/seccomp_filter.txt 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 @@ -407,6 +416,7 @@ config HAVE_GCC_PLUGINS menuconfig GCC_PLUGINS bool "GCC plugins" depends on HAVE_GCC_PLUGINS + depends on PLUGIN_HOSTCC != "" depends on !COMPILE_TEST help GCC plugins are loadable modules that provide extra features to the diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include index bf7c0c9fa3a4..dad5583451af 100644 --- a/scripts/Kconfig.include +++ b/scripts/Kconfig.include @@ -25,3 +25,6 @@ cc-option = $(success,$(CC) -Werror $(1) -E -x c /dev/null -o /dev/null) # $(ld-option,) # Return y if the linker supports , n otherwise ld-option = $(success,$(LD) -v $(1)) + +# gcc version including patch level +gcc-version := $(shell,$(srctree)/scripts/gcc-version.sh -p $(CC) | sed 's/^0*//') diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins index 32bdf184eced..c961b9a65d11 100644 --- a/scripts/Makefile.gcc-plugins +++ b/scripts/Makefile.gcc-plugins @@ -1,72 +1,37 @@ # SPDX-License-Identifier: GPL-2.0 -ifdef CONFIG_GCC_PLUGINS - __PLUGINCC := $(call cc-ifversion, -ge, 0408, $(HOSTCXX), $(HOSTCC)) - PLUGINCC := $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-plugin.sh "$(__PLUGINCC)" "$(HOSTCXX)" "$(CC)") - - SANCOV_PLUGIN := -fplugin=$(objtree)/scripts/gcc-plugins/sancov_plugin.so - - gcc-plugin-$(CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) += cyc_complexity_plugin.so +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-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY) += -DLATENT_ENTROPY_PLUGIN - ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY +gcc-plugin-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY) += latent_entropy_plugin.so +gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY) += -DLATENT_ENTROPY_PLUGIN +ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY DISABLE_LATENT_ENTROPY_PLUGIN += -fplugin-arg-latent_entropy_plugin-disable - endif - - ifdef CONFIG_GCC_PLUGIN_SANCOV - # It is needed because of the gcc-plugin.sh and gcc version checks. - gcc-plugin-$(CONFIG_GCC_PLUGIN_SANCOV) += sancov_plugin.so - - ifeq ($(PLUGINCC),) - $(warning warning: cannot use CONFIG_KCOV: -fsanitize-coverage=trace-pc is not supported by compiler) - endif - endif - - gcc-plugin-$(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-$(CONFIG_GCC_PLUGIN_STRUCTLEAK) += -DSTRUCTLEAK_PLUGIN +endif - gcc-plugin-$(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-$(CONFIG_GCC_PLUGIN_SANCOV) += sancov_plugin.so +gcc-plugin-$(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_PLUGINS_CFLAGS := $(strip $(addprefix -fplugin=$(objtree)/scripts/gcc-plugins/, $(gcc-plugin-y)) $(gcc-plugin-cflags-y)) +gcc-plugin-$(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 - export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN GCC_PLUGIN_SUBDIR - export DISABLE_LATENT_ENTROPY_PLUGIN +GCC_PLUGINS_CFLAGS := $(strip $(addprefix -fplugin=$(objtree)/scripts/gcc-plugins/, $(gcc-plugin-y)) $(gcc-plugin-cflags-y)) - ifneq ($(PLUGINCC),) - # SANCOV_PLUGIN can be only in CFLAGS_KCOV because avoid duplication. - GCC_PLUGINS_CFLAGS := $(filter-out $(SANCOV_PLUGIN), $(GCC_PLUGINS_CFLAGS)) - endif +export GCC_PLUGINS_CFLAGS GCC_PLUGIN GCC_PLUGIN_SUBDIR +export DISABLE_LATENT_ENTROPY_PLUGIN - KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS) - GCC_PLUGIN := $(gcc-plugin-y) - GCC_PLUGIN_SUBDIR := $(gcc-plugin-subdir-y) -endif +# sancov_plugin.so can be only in CFLAGS_KCOV because avoid duplication. +GCC_PLUGINS_CFLAGS := $(filter-out %/sancov_plugin.so, $(GCC_PLUGINS_CFLAGS)) -# If plugins aren't supported, abort the build before hard-to-read compiler -# errors start getting spewed by the main build. -PHONY += gcc-plugins-check -gcc-plugins-check: FORCE -ifdef CONFIG_GCC_PLUGINS - ifeq ($(PLUGINCC),) - ifneq ($(GCC_PLUGINS_CFLAGS),) - ifeq ($(call cc-ifversion, -ge, 0405, y), y) - $(Q)$(srctree)/scripts/gcc-plugin.sh --show-error "$(__PLUGINCC)" "$(HOSTCXX)" "$(CC)" || true - @echo "Cannot use CONFIG_GCC_PLUGINS: your gcc installation does not support plugins, perhaps the necessary headers are missing?" >&2 && exit 1 - else - @echo "Cannot use CONFIG_GCC_PLUGINS: your gcc version does not support plugins, you should upgrade it to at least gcc 4.5" >&2 && exit 1 - endif - endif - endif -endif - @: +KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS) +GCC_PLUGIN := $(gcc-plugin-y) +GCC_PLUGIN_SUBDIR := $(gcc-plugin-subdir-y) # Actually do the build, if requested. PHONY += gcc-plugins -gcc-plugins: scripts_basic gcc-plugins-check +gcc-plugins: scripts_basic ifdef CONFIG_GCC_PLUGINS $(Q)$(MAKE) $(build)=scripts/gcc-plugins endif diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile index ea465799ced5..326254653bd0 100644 --- a/scripts/gcc-plugins/Makefile +++ b/scripts/gcc-plugins/Makefile @@ -1,4 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 +PLUGINCC := $(CONFIG_PLUGIN_HOSTCC:"%"=%) GCC_PLUGINS_DIR := $(shell $(CC) -print-file-name=plugin) ifeq ($(PLUGINCC),$(HOSTCC)) -- cgit v1.2.3