Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild

Pull kbuild updates from Michal Marek:

 - GCC plugin support by Emese Revfy from grsecurity, with a fixup from
   Kees Cook.  The plugins are meant to be used for static analysis of
   the kernel code.  Two plugins are provided already.

 - reduction of the gcc commandline by Arnd Bergmann.

 - IS_ENABLED / IS_REACHABLE macro enhancements by Masahiro Yamada

 - bin2c fix by Michael Tautschnig

 - setlocalversion fix by Wolfram Sang

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  gcc-plugins: disable under COMPILE_TEST
  kbuild: Abort build on bad stack protector flag
  scripts: Fix size mismatch of kexec_purgatory_size
  kbuild: make samples depend on headers_install
  Kbuild: don't add obj tree in additional includes
  Kbuild: arch: look for generated headers in obtree
  Kbuild: always prefix objtree in LINUXINCLUDE
  Kbuild: avoid duplicate include path
  Kbuild: don't add ../../ to include path
  vmlinux.lds.h: replace config_enabled() with IS_ENABLED()
  kconfig.h: allow to use IS_{ENABLE,REACHABLE} in macro expansion
  kconfig.h: use already defined macros for IS_REACHABLE() define
  export.h: use __is_defined() to check if __KSYM_* is defined
  kconfig.h: use __is_defined() to check if MODULE is defined
  kbuild: setlocalversion: print error to STDERR
  Add sancov plugin
  Add Cyclomatic complexity GCC plugin
  GCC plugin infrastructure
  Shared library support

43 files changed, 2252 insertions, 54 deletions

diff --git a/.gitignore b/.gitignore
index 0c320bf02586..2be25f771bd8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -37,6 +37,7 @@ modules.builtin
 Module.symvers
 *.dwo
 *.su
+*.c.[012]*.*
 
 #
 # Top-level generic files
diff --git a/Documentation/dontdiff b/Documentation/dontdiff
index 8ea834f6b289..5385cba941d2 100644
--- a/Documentation/dontdiff
+++ b/Documentation/dontdiff
@@ -3,6 +3,7 @@
 *.bc
 *.bin
 *.bz2
+*.c.[012]*.*
 *.cis
 *.cpio
 *.csp
diff --git a/Documentation/gcc-plugins.txt b/Documentation/gcc-plugins.txt
new file mode 100644
index 000000000000..891c69464434
--- /dev/null
+++ b/Documentation/gcc-plugins.txt
@@ -0,0 +1,87 @@
+GCC plugin infrastructure
+=========================
+
+
+1. 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 and arm64
+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/
+
+
+2. 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.
+
+
+3. 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
+
+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/MAINTAINERS b/MAINTAINERS
index 25f43204014d..8f950e2752de 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5094,6 +5094,15 @@ L:	linux-scsi@vger.kernel.org
 S:	Odd Fixes (e.g., new signatures)
 F:	drivers/scsi/fdomain.*
 
+GCC PLUGINS
+M:	Kees Cook <keescook@chromium.org>
+R:	Emese Revfy <re.emese@gmail.com>
+L:	kernel-hardening@lists.openwall.com
+S:	Maintained
+F:	scripts/gcc-plugins/
+F:	scripts/gcc-plugin.sh
+F:	Documentation/gcc-plugins.txt
+
 GCOV BASED KERNEL PROFILING
 M:	Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
 S:	Maintained
diff --git a/Makefile b/Makefile
index 393b6159ae92..d6d401bf9d95 100644
--- a/Makefile
+++ b/Makefile
@@ -371,26 +371,27 @@ CFLAGS_KERNEL	=
 AFLAGS_KERNEL	=
 LDFLAGS_vmlinux =
 CFLAGS_GCOV	= -fprofile-arcs -ftest-coverage -fno-tree-loop-im
-CFLAGS_KCOV	= -fsanitize-coverage=trace-pc
+CFLAGS_KCOV	:= $(call cc-option,-fsanitize-coverage=trace-pc,)
 
 
 # Use USERINCLUDE when you must reference the UAPI directories only.
 USERINCLUDE    := \
 		-I$(srctree)/arch/$(hdr-arch)/include/uapi \
-		-Iarch/$(hdr-arch)/include/generated/uapi \
+		-I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
 		-I$(srctree)/include/uapi \
-		-Iinclude/generated/uapi \
+		-I$(objtree)/include/generated/uapi \
                 -include $(srctree)/include/linux/kconfig.h
 
 # Use LINUXINCLUDE when you must reference the include/ directory.
 # Needed to be compatible with the O= option
 LINUXINCLUDE    := \
 		-I$(srctree)/arch/$(hdr-arch)/include \
-		-Iarch/$(hdr-arch)/include/generated/uapi \
-		-Iarch/$(hdr-arch)/include/generated \
+		-I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
+		-I$(objtree)/arch/$(hdr-arch)/include/generated \
 		$(if $(KBUILD_SRC), -I$(srctree)/include) \
-		-Iinclude \
-		$(USERINCLUDE)
+		-I$(objtree)/include
+
+LINUXINCLUDE	+= $(filter-out $(LINUXINCLUDE),$(USERINCLUDE))
 
 KBUILD_CPPFLAGS := -D__KERNEL__
 
@@ -554,7 +555,7 @@ 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
@@ -635,6 +636,15 @@ 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
 # Disable optimizations that make assembler listings hard to read.
 # reorder blocks reorders the control in the function
@@ -666,21 +676,11 @@ endif
 endif
 # Find arch-specific stack protector compiler sanity-checking script.
 ifdef CONFIG_CC_STACKPROTECTOR
-  stackp-path := $(srctree)/scripts/gcc-$(ARCH)_$(BITS)-has-stack-protector.sh
-  ifneq ($(wildcard $(stackp-path)),)
-    stackp-check := $(stackp-path)
-  endif
+  stackp-path := $(srctree)/scripts/gcc-$(SRCARCH)_$(BITS)-has-stack-protector.sh
+  stackp-check := $(wildcard $(stackp-path))
 endif
 KBUILD_CFLAGS += $(stackp-flag)
 
-ifdef CONFIG_KCOV
-  ifeq ($(call cc-option, $(CFLAGS_KCOV)),)
-    $(warning Cannot use CONFIG_KCOV: \
-             -fsanitize-coverage=trace-pc is not supported by compiler)
-    CFLAGS_KCOV =
-  endif
-endif
-
 ifeq ($(cc-name),clang)
 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
 KBUILD_CPPFLAGS += $(call cc-option,-Wno-unknown-warning-option,)
@@ -1019,7 +1019,7 @@ prepare1: prepare2 $(version_h) include/generated/utsrelease.h \
 
 archprepare: archheaders archscripts prepare1 scripts_basic
 
-prepare0: archprepare
+prepare0: archprepare gcc-plugins
 	$(Q)$(MAKE) $(build)=.
 
 # All the preparing..
@@ -1531,6 +1531,7 @@ clean: $(clean-dirs)
 		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
 		-o -name '*.symtypes' -o -name 'modules.order' \
 		-o -name modules.builtin -o -name '.tmp_*.o.*' \
+		-o -name '*.c.[012]*.*' \
 		-o -name '*.gcno' \) -type f -print | xargs rm -f
 
 # Generate tags for editors
@@ -1641,7 +1642,7 @@ endif
 	$(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
 	$(build)=$(build-dir)
 # Make sure the latest headers are built for Documentation
-Documentation/: headers_install
+Documentation/ samples/: headers_install
 %/: prepare scripts FORCE
 	$(cmd_crmodverdir)
 	$(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
diff --git a/arch/Kconfig b/arch/Kconfig
index 15996290fed4..bd8056b5b246 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -357,6 +357,43 @@ config SECCOMP_FILTER
 
 	  See Documentation/prctl/seccomp_filter.txt for details.
 
+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 !COMPILE_TEST
+	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"
+	depends on GCC_PLUGINS
+	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).
+
+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 HAVE_CC_STACKPROTECTOR
 	bool
 	help
diff --git a/arch/alpha/boot/Makefile b/arch/alpha/boot/Makefile
index 8399bd0e68e8..0cbe4c59d3ce 100644
--- a/arch/alpha/boot/Makefile
+++ b/arch/alpha/boot/Makefile
@@ -15,7 +15,7 @@ targets		:= vmlinux.gz vmlinux \
 OBJSTRIP	:= $(obj)/tools/objstrip
 
 HOSTCFLAGS	:= -Wall -I$(objtree)/usr/include
-BOOTCFLAGS	+= -I$(obj) -I$(srctree)/$(obj)
+BOOTCFLAGS	+= -I$(objtree)/$(obj) -I$(srctree)/$(obj)
 
 # SRM bootable image.  Copy to offset 512 of a partition.
 $(obj)/bootimage: $(addprefix $(obj)/tools/,mkbb lxboot bootlx) $(obj)/vmlinux.nh
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 14b4cf75ceec..fc3dc0b90be2 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -54,6 +54,7 @@ config ARM
 	select HAVE_FTRACE_MCOUNT_RECORD if (!XIP_KERNEL)
 	select HAVE_FUNCTION_GRAPH_TRACER if (!THUMB2_KERNEL)
 	select HAVE_FUNCTION_TRACER if (!XIP_KERNEL)
+	select HAVE_GCC_PLUGINS
 	select HAVE_GENERIC_DMA_COHERENT
 	select HAVE_HW_BREAKPOINT if (PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7))
 	select HAVE_IDE if PCI || ISA || PCMCIA
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 9f8b99e20557..1b06db571fff 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -78,6 +78,7 @@ config ARM64
 	select HAVE_FTRACE_MCOUNT_RECORD
 	select HAVE_FUNCTION_TRACER
 	select HAVE_FUNCTION_GRAPH_TRACER
+	select HAVE_GCC_PLUGINS
 	select HAVE_GENERIC_DMA_COHERENT
 	select HAVE_HW_BREAKPOINT if PERF_EVENTS
 	select HAVE_IRQ_TIME_ACCOUNTING
diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
index 4cd612a6e272..1a2a6e8dc40d 100644
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile
@@ -43,7 +43,7 @@ ifeq ($(call cc-option-yn, -fstack-protector),y)
 BOOTCFLAGS	+= -fno-stack-protector
 endif
 
-BOOTCFLAGS	+= -I$(obj) -I$(srctree)/$(obj)
+BOOTCFLAGS	+= -I$(objtree)/$(obj) -I$(srctree)/$(obj)
 
 DTC_FLAGS	?= -p 1024
 
diff --git a/arch/powerpc/kvm/Makefile b/arch/powerpc/kvm/Makefile
index eba0bea6e032..1f9e5529e692 100644
--- a/arch/powerpc/kvm/Makefile
+++ b/arch/powerpc/kvm/Makefile
@@ -20,7 +20,7 @@ common-objs-y += powerpc.o emulate.o emulate_loadstore.o
 obj-$(CONFIG_KVM_EXIT_TIMING) += timing.o
 obj-$(CONFIG_KVM_BOOK3S_HANDLER) += book3s_exports.o
 
-AFLAGS_booke_interrupts.o := -I$(obj)
+AFLAGS_booke_interrupts.o := -I$(objtree)/$(obj)
 
 kvm-e500-objs := \
 	$(common-objs-y) \
diff --git a/arch/s390/boot/compressed/Makefile b/arch/s390/boot/compressed/Makefile
index 13723c39e58e..33ba697c782d 100644
--- a/arch/s390/boot/compressed/Makefile
+++ b/arch/s390/boot/compressed/Makefile
@@ -33,10 +33,10 @@ quiet_cmd_sizes = GEN $@
 $(obj)/sizes.h: vmlinux
 	$(call if_changed,sizes)
 
-AFLAGS_head.o += -I$(obj)
+AFLAGS_head.o += -I$(objtree)/$(obj)
 $(obj)/head.o: $(obj)/sizes.h
 
-CFLAGS_misc.o += -I$(obj)
+CFLAGS_misc.o += -I$(objtree)/$(obj)
 $(obj)/misc.o: $(obj)/sizes.h
 
 OBJCOPYFLAGS_vmlinux.bin :=  -R .comment -S
diff --git a/arch/um/Kconfig.common b/arch/um/Kconfig.common
index cc0013475444..58650d098fb4 100644
--- a/arch/um/Kconfig.common
+++ b/arch/um/Kconfig.common
@@ -9,6 +9,7 @@ config UML
 	select GENERIC_CPU_DEVICES
 	select GENERIC_IO
 	select GENERIC_CLOCKEVENTS
+	select HAVE_GCC_PLUGINS
 	select TTY # Needed for line.c
 
 config MMU
diff --git a/arch/um/Makefile b/arch/um/Makefile
index e3abe6f3156d..0ca46ededfc7 100644
--- a/arch/um/Makefile
+++ b/arch/um/Makefile
@@ -78,8 +78,8 @@ include $(ARCH_DIR)/Makefile-os-$(OS)
 
 KBUILD_CPPFLAGS += -I$(srctree)/$(HOST_DIR)/include \
 		   -I$(srctree)/$(HOST_DIR)/include/uapi \
-		   -I$(HOST_DIR)/include/generated \
-		   -I$(HOST_DIR)/include/generated/uapi
+		   -I$(objtree)/$(HOST_DIR)/include/generated \
+		   -I$(objtree)/$(HOST_DIR)/include/generated/uapi
 
 # -Derrno=kernel_errno - This turns all kernel references to errno into
 # kernel_errno to separate them from the libc errno.  This allows -fno-common
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 2fa55851d2a9..3a9add58d794 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -111,6 +111,7 @@ config X86
 	select HAVE_FUNCTION_GRAPH_FP_TEST
 	select HAVE_FUNCTION_GRAPH_TRACER
 	select HAVE_FUNCTION_TRACER
+	select HAVE_GCC_PLUGINS
 	select HAVE_GENERIC_DMA_COHERENT	if X86_32
 	select HAVE_HW_BREAKPOINT
 	select HAVE_IDE
diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index be8e688fa0d4..12ea8f8384f4 100644
--- a/arch/x86/boot/Makefile
+++ b/arch/x86/boot/Makefile
@@ -96,7 +96,7 @@ $(obj)/zoffset.h: $(obj)/compressed/vmlinux FORCE
 	$(call if_changed,zoffset)
 
 
-AFLAGS_header.o += -I$(obj)
+AFLAGS_header.o += -I$(objtree)/$(obj)
 $(obj)/header.o: $(obj)/zoffset.h
 
 LDFLAGS_setup.elf	:= -T
diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile
index 6ba89a1ab0e5..d5409660f5de 100644
--- a/arch/x86/entry/vdso/Makefile
+++ b/arch/x86/entry/vdso/Makefile
@@ -75,7 +75,7 @@ CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \
        -fno-omit-frame-pointer -foptimize-sibling-calls \
        -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO
 
-$(vobjs): KBUILD_CFLAGS += $(CFL)
+$(vobjs): KBUILD_CFLAGS := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS)) $(CFL)
 
 #
 # vDSO code runs in userspace and -pg doesn't help with profiling anyway.
@@ -145,6 +145,7 @@ KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS))
 KBUILD_CFLAGS_32 := $(filter-out -mcmodel=kernel,$(KBUILD_CFLAGS_32))
 KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32))
 KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32))
+KBUILD_CFLAGS_32 := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS_32))
 KBUILD_CFLAGS_32 += -m32 -msoft-float -mregparm=0 -fpic
 KBUILD_CFLAGS_32 += $(call cc-option, -fno-stack-protector)
 KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls)
diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile
index 12734a96df47..ac58c1616408 100644
--- a/arch/x86/purgatory/Makefile
+++ b/arch/x86/purgatory/Makefile
@@ -8,6 +8,8 @@ PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))
 LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined -nostdlib -z nodefaultlib
 targets += purgatory.ro
 
+KCOV_INSTRUMENT := n
+
 # Default KBUILD_CFLAGS can have -pg option set when FTRACE is enabled. That
 # in turn leaves some undefined symbols like __fentry__ in purgatory and not
 # sure how to relocate those. Like kexec-tools, use custom flags.
diff --git a/arch/x86/realmode/rm/Makefile b/arch/x86/realmode/rm/Makefile
index c556c5ae8de5..25012abc3409 100644
--- a/arch/x86/realmode/rm/Makefile
+++ b/arch/x86/realmode/rm/Makefile
@@ -48,7 +48,7 @@ targets += realmode.lds
 $(obj)/realmode.lds: $(obj)/pasyms.h
 
 LDFLAGS_realmode.elf := --emit-relocs -T
-CPPFLAGS_realmode.lds += -P -C -I$(obj)
+CPPFLAGS_realmode.lds += -P -C -I$(objtree)/$(obj)
 
 targets += realmode.elf
 $(obj)/realmode.elf: $(obj)/realmode.lds $(REALMODE_OBJS) FORCE
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 54643d1f5af4..24563970ff7b 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -164,7 +164,7 @@
 
 #define ___OF_TABLE(cfg, name)	_OF_TABLE_##cfg(name)
 #define __OF_TABLE(cfg, name)	___OF_TABLE(cfg, name)
-#define OF_TABLE(cfg, name)	__OF_TABLE(config_enabled(cfg), name)
+#define OF_TABLE(cfg, name)	__OF_TABLE(IS_ENABLED(cfg), name)
 #define _OF_TABLE_0(name)
 #define _OF_TABLE_1(name)						\
 	. = ALIGN(8);							\
diff --git a/include/linux/export.h b/include/linux/export.h
index 2f9ccbe6a639..c565f87f005e 100644
--- a/include/linux/export.h
+++ b/include/linux/export.h
@@ -82,7 +82,7 @@ extern struct module __this_module;
 #include <generated/autoksyms.h>
 
 #define __EXPORT_SYMBOL(sym, sec)				\
-	__cond_export_sym(sym, sec, config_enabled(__KSYM_##sym))
+	__cond_export_sym(sym, sec, __is_defined(__KSYM_##sym))
 #define __cond_export_sym(sym, sec, conf)			\
 	___cond_export_sym(sym, sec, conf)
 #define ___cond_export_sym(sym, sec, enabled)			\
diff --git a/include/linux/kconfig.h b/include/linux/kconfig.h
index b33c7797eb57..15ec117ec537 100644
--- a/include/linux/kconfig.h
+++ b/include/linux/kconfig.h
@@ -3,6 +3,21 @@
 
 #include <generated/autoconf.h>
 
+#define __ARG_PLACEHOLDER_1 0,
+#define __take_second_arg(__ignored, val, ...) val
+
+/*
+ * The use of "&&" / "||" is limited in certain expressions.
+ * The followings enable to calculate "and" / "or" with macro expansion only.
+ */
+#define __and(x, y)			___and(x, y)
+#define ___and(x, y)			____and(__ARG_PLACEHOLDER_##x, y)
+#define ____and(arg1_or_junk, y)	__take_second_arg(arg1_or_junk y, 0)
+
+#define __or(x, y)			___or(x, y)
+#define ___or(x, y)			____or(__ARG_PLACEHOLDER_##x, y)
+#define ____or(arg1_or_junk, y)		__take_second_arg(arg1_or_junk 1, y)
+
 /*
  * Helper macros to use CONFIG_ options in C/CPP expressions. Note that
  * these only work with boolean and tristate options.
@@ -16,11 +31,10 @@
  * When CONFIG_BOOGER is not defined, we generate a (... 1, 0) pair, and when
  * the last step cherry picks the 2nd arg, we get a zero.
  */
-#define __ARG_PLACEHOLDER_1 0,
-#define config_enabled(cfg) _config_enabled(cfg)
-#define _config_enabled(value) __config_enabled(__ARG_PLACEHOLDER_##value)
-#define __config_enabled(arg1_or_junk) ___config_enabled(arg1_or_junk 1, 0)
-#define ___config_enabled(__ignored, val, ...) val
+#define config_enabled(cfg)		___is_defined(cfg)
+#define __is_defined(x)			___is_defined(x)
+#define ___is_defined(val)		____is_defined(__ARG_PLACEHOLDER_##val)
+#define ____is_defined(arg1_or_junk)	__take_second_arg(arg1_or_junk 1, 0)
 
 /*
  * IS_BUILTIN(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y', 0
@@ -41,14 +55,13 @@
  * This is similar to IS_ENABLED(), but returns false when invoked from
  * built-in code when CONFIG_FOO is set to 'm'.
  */
-#define IS_REACHABLE(option) (config_enabled(option) || \
-		 (config_enabled(option##_MODULE) && config_enabled(MODULE)))
+#define IS_REACHABLE(option) __or(IS_BUILTIN(option), \
+				__and(IS_MODULE(option), __is_defined(MODULE)))
 
 /*
  * IS_ENABLED(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y' or 'm',
  * 0 otherwise.
  */
-#define IS_ENABLED(option) \
-	(IS_BUILTIN(option) || IS_MODULE(option))
+#define IS_ENABLED(option) __or(IS_BUILTIN(option), IS_MODULE(option))
 
 #endif /* __LINUX_KCONFIG_H */
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index f07842e2d69f..eb8917a71489 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -709,6 +709,8 @@ config KCOV
 	bool "Code coverage for fuzzing"
 	depends on ARCH_HAS_KCOV
 	select DEBUG_FS
+	select GCC_PLUGINS if !COMPILE_TEST
+	select GCC_PLUGIN_SANCOV if !COMPILE_TEST
 	help
 	  KCOV exposes kernel code coverage information in a form suitable
 	  for coverage-guided fuzzing (randomized testing).
diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
index 0f82314621f2..15b196fc2f49 100644
--- a/scripts/Kbuild.include
+++ b/scripts/Kbuild.include
@@ -202,7 +202,7 @@ hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
 # Prefix -I with $(srctree) if it is not an absolute path.
 # skip if -I has no parameter
 addtree = $(if $(patsubst -I%,%,$(1)), \
-$(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1))) $(1))
+$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1)))
 
 # Find all -I options and call addtree
 flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o)))
diff --git a/scripts/Makefile b/scripts/Makefile
index 822ab4a6a4aa..1d80897a9644 100644
--- a/scripts/Makefile
+++ b/scripts/Makefile
@@ -47,4 +47,4 @@ subdir-$(CONFIG_DTC)         += dtc
 subdir-$(CONFIG_GDB_SCRIPTS) += gdb
 
 # Let clean descend into subdirs
-subdir-	+= basic kconfig package
+subdir-	+= basic kconfig package gcc-plugins
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 0d1ca5bf42fb..11602e5efb3b 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -60,7 +60,7 @@ endif
 endif
 
 # Do not include host rules unless needed
-ifneq ($(hostprogs-y)$(hostprogs-m),)
+ifneq ($(hostprogs-y)$(hostprogs-m)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),)
 include scripts/Makefile.host
 endif
 
diff --git a/scripts/Makefile.clean b/scripts/Makefile.clean
index 55c96cb8070f..50616ea25131 100644
--- a/scripts/Makefile.clean
+++ b/scripts/Makefile.clean
@@ -38,7 +38,9 @@ subdir-ymn	:= $(addprefix $(obj)/,$(subdir-ymn))
 __clean-files	:= $(extra-y) $(extra-m) $(extra-)       \
 		   $(always) $(targets) $(clean-files)   \
 		   $(host-progs)                         \
-		   $(hostprogs-y) $(hostprogs-m) $(hostprogs-)
+		   $(hostprogs-y) $(hostprogs-m) $(hostprogs-) \
+		   $(hostlibs-y) $(hostlibs-m) $(hostlibs-) \
+		   $(hostcxxlibs-y) $(hostcxxlibs-m)
 
 __clean-files   := $(filter-out $(no-clean-files), $(__clean-files))
 
diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins
new file mode 100644
index 000000000000..5e22b60589c1
--- /dev/null
+++ b/scripts/Makefile.gcc-plugins
@@ -0,0 +1,43 @@
+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
+
+  ifdef CONFIG_GCC_PLUGIN_SANCOV
+    ifeq ($(CFLAGS_KCOV),)
+      # It is needed because of the gcc-plugin.sh and gcc version checks.
+      gcc-plugin-$(CONFIG_GCC_PLUGIN_SANCOV)           += sanco