[kernel-hardening] Re: [PATCH v5 2/5] GCC plugin infrastructure

Masahiro Yamada
2016-04-02T04:32:40Z

Hi Emese,

Sorry for my late reply.

> Thanks for the patch. I tested it and there is a problem when I run a parallel make.
> The plugins are compiled later than needed (e.g., scripts/mod/empty.o). There is a lot of important
> code under scripts/mod which may need the plugins.

Ah, I missed that.

> If the plugins were compiled when the "scripts_basic"
> target runs it would be good but unfortunately the config symbol CONFIG_GCC_PLUGINS doesn't seem to be defined yet.
> Could you please help me solve this problem?

How about this?

It should apply on commit 0b005b886bde6c4b9134d01f830d88d464911a65
of your tree.

diff --git a/Makefile b/Makefile
index 1c7a379..d3518e0 100644
--- a/Makefile
+++ b/Makefile
@@ -550,7 +550,7 @@ ifeq ($(KBUILD_EXTMOD),)
# in parallel
PHONY += scripts
scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
- asm-generic
+ asm-generic gcc-plugins
$(Q)$(MAKE) $(build)=$(@)

# Objects we will link into vmlinux / subdirs we need to visit
@@ -625,6 +625,13 @@ endif
# Tell gcc to never replace conditional load with a non-conditional one
KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)

+PHONY += gcc-plugins
+gcc-plugins: scripts_basic
+ifdef CONFIG_GCC_PLUGINS
+ $(Q)$(MAKE) $(build)=scripts/gcc-plugins
+endif
+ @:
+
include scripts/Makefile.gcc-plugins

ifdef CONFIG_READABLE_ASM
@@ -1008,7 +1015,7 @@ archprepare: archheaders archscripts prepare1
scripts_basic

prepare0: KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS)
prepare0: KBUILD_AFLAGS += $(GCC_PLUGINS_AFLAGS)
-prepare0: archprepare FORCE
+prepare0: archprepare gcc-plugins FORCE
$(Q)$(MAKE) $(build)=.

# All the preparing..
diff --git a/scripts/Makefile b/scripts/Makefile
index 0ba652c..1d80897 100644
--- a/scripts/Makefile
+++ b/scripts/Makefile
@@ -45,7 +45,6 @@ subdir-y += mod
subdir-$(CONFIG_SECURITY_SELINUX) += selinux
subdir-$(CONFIG_DTC) += dtc
subdir-$(CONFIG_GDB_SCRIPTS) += gdb
-subdir-$(CONFIG_GCC_PLUGINS) += gcc-plugins

# Let clean descend into subdirs
-subdir- += basic kconfig package
+subdir- += basic kconfig package gcc-plugins

--
Best Regards
Masahiro Yamada