From 73a4f6dbe70a1b93c11e2d1d6ca68f3522daf434 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 10 Dec 2017 01:02:28 +0900 Subject: kbuild: add LEX and YACC variables Allow users to use their favorite lexer / parser generators. This is useful for me to test various flex and bison versions. Signed-off-by: Masahiro Yamada --- scripts/Makefile.lib | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts/Makefile.lib') diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 1ca4dcd2d500..ee528e30f80f 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -193,7 +193,7 @@ ifdef REGENERATE_PARSERS LEX_PREFIX = $(if $(LEX_PREFIX_${baseprereq}),$(LEX_PREFIX_${baseprereq}),yy) quiet_cmd_flex = LEX $@ - cmd_flex = flex -o$@ -L -P $(LEX_PREFIX) $< + cmd_flex = $(LEX) -o$@ -L -P $(LEX_PREFIX) $< .PRECIOUS: $(src)/%.lex.c_shipped $(src)/%.lex.c_shipped: $(src)/%.l @@ -204,7 +204,7 @@ $(src)/%.lex.c_shipped: $(src)/%.l YACC_PREFIX = $(if $(YACC_PREFIX_${baseprereq}),$(YACC_PREFIX_${baseprereq}),yy) quiet_cmd_bison = YACC $@ - cmd_bison = bison -o$@ -t -l -p $(YACC_PREFIX) $< + cmd_bison = $(YACC) -o$@ -t -l -p $(YACC_PREFIX) $< .PRECIOUS: $(src)/%.tab.c_shipped $(src)/%.tab.c_shipped: $(src)/%.y -- cgit v1.2.3 From 033dba2ec06c47a9fe1b190bc3281058fb20738d Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 10 Dec 2017 01:02:29 +0900 Subject: kbuild: prepare to remove C files pre-generated by flex and bison In Linux build system convention, pre-generated files are version- controlled with a "_shipped" suffix. During the kernel building, they are simply shipped (copied) removing the suffix. This approach can reduce external tool dependency for the kernel build, but it is tedious to manually regenerate such artifacts from developers' point of view. (We need to do "make REGENERATE_PARSERS=1" every time we touch real source files such as *.l, *.y) Some months ago, I sent out RFC patches to run flex, bison, and gperf during the build. In the review and test, Linus noticed gperf-3.1 had changed the lookup function prototype. Then, the use of gperf in kernel was entirely removed by commit bb3290d91695 ("Remove gperf usage from toolchain"). This time, I tested several versions of flex and bison, and I was not hit by any compatibility issue except a flaw in flex-2.6.3; if you generate lexer for dtc and genksyms with flex-2.6.3, you will see "yywrap redefined" warning. This was not intentional, but a bug, fixed by flex-2.6.4. Otherwise, both flex and bison look fairly stable for a long time. This commit prepares some build rules to remove the _shipped files. Also, document minimal requirement for flex and bison. Rationale for the minimal version: The -Wmissing-prototypes option of GCC warns "no previous prototype" for lexers generated by flex-2.5.34 or older, so I chose 2.5.35 as the required version for flex. Flex-2.5.35 was released in 2008. Bison looks more stable. I did not see any problem with bison-2.0, released in 2004. I did not test bison-1.x, but bison-2.0 should be old enough. Tested flex versions: 2.5.35 2.5.36 2.5.37 2.5.39 2.6.0 2.6.1 2.6.2 2.6.3 (*) 2.6.4 (*) flex-2.6.3 causes "yywrap redefined" warning Tested bison versions: 2.0 2.1 2.2 2.3 2.4 2.4.1 2.5.1 2.6 2.6.1 2.6.2 2.6.3 2.6.4 2.6.5 2.7 2.7.1 3.0 3.0.1 3.0.2 3.0.3 3.0.4 Signed-off-by: Masahiro Yamada --- Documentation/process/changes.rst | 25 +++++++++++++++++++++++++ scripts/Makefile.lib | 20 +++++++++++++++++--- 2 files changed, 42 insertions(+), 3 deletions(-) (limited to 'scripts/Makefile.lib') diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst index 560beaef5a7c..81cdb528ad46 100644 --- a/Documentation/process/changes.rst +++ b/Documentation/process/changes.rst @@ -32,6 +32,8 @@ you probably needn't concern yourself with isdn4k-utils. GNU C 3.2 gcc --version GNU make 3.81 make --version binutils 2.20 ld -v +flex 2.5.35 flex --version +bison 2.0 bison --version util-linux 2.10o fdformat --version module-init-tools 0.9.10 depmod -V e2fsprogs 1.41.4 e2fsck -V @@ -79,6 +81,19 @@ The build system has, as of 4.13, switched to using thin archives (`ar T`) rather than incremental linking (`ld -r`) for built-in.o intermediate steps. This requires binutils 2.20 or newer. +Flex +---- + +Since Linux 4.16, the build system generates lexical analyzers +during build. This requires flex 2.5.35 or later. + + +Bison +----- + +Since Linux 4.16, the build system generates parsers +during build. This requires bison 2.0 or later. + Perl ---- @@ -333,6 +348,16 @@ Binutils - +Flex +---- + +- + +Bison +----- + +- + OpenSSL ------- diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index ee528e30f80f..0f9ef3fbbaf5 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -186,8 +186,6 @@ $(foreach m, $(notdir $1), \ $(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s))))))) endef -ifdef REGENERATE_PARSERS - # LEX # --------------------------------------------------------------------------- LEX_PREFIX = $(if $(LEX_PREFIX_${baseprereq}),$(LEX_PREFIX_${baseprereq}),yy) @@ -195,9 +193,15 @@ LEX_PREFIX = $(if $(LEX_PREFIX_${baseprereq}),$(LEX_PREFIX_${baseprereq}),yy) quiet_cmd_flex = LEX $@ cmd_flex = $(LEX) -o$@ -L -P $(LEX_PREFIX) $< +ifdef REGENERATE_PARSERS .PRECIOUS: $(src)/%.lex.c_shipped $(src)/%.lex.c_shipped: $(src)/%.l $(call cmd,flex) +endif + +.PRECIOUS: $(obj)/%.lex.c +$(filter %.lex.c,$(targets)): $(obj)/%.lex.c: $(src)/%.l FORCE + $(call if_changed,flex) # YACC # --------------------------------------------------------------------------- @@ -206,19 +210,29 @@ YACC_PREFIX = $(if $(YACC_PREFIX_${baseprereq}),$(YACC_PREFIX_${baseprereq}),yy) quiet_cmd_bison = YACC $@ cmd_bison = $(YACC) -o$@ -t -l -p $(YACC_PREFIX) $< +ifdef REGENERATE_PARSERS .PRECIOUS: $(src)/%.tab.c_shipped $(src)/%.tab.c_shipped: $(src)/%.y $(call cmd,bison) +endif + +.PRECIOUS: $(obj)/%.tab.c +$(filter %.tab.c,$(targets)): $(obj)/%.tab.c: $(src)/%.y FORCE + $(call if_changed,bison) quiet_cmd_bison_h = YACC $@ cmd_bison_h = bison -o/dev/null --defines=$@ -t -l -p $(YACC_PREFIX) $< +ifdef REGENERATE_PARSERS .PRECIOUS: $(src)/%.tab.h_shipped $(src)/%.tab.h_shipped: $(src)/%.y $(call cmd,bison_h) - endif +.PRECIOUS: $(obj)/%.tab.h +$(filter %.tab.h,$(targets)): $(obj)/%.tab.h: $(src)/%.y FORCE + $(call if_changed,bison_h) + # Shipped files # =========================================================================== -- cgit v1.2.3 From eea199b445f64c038b1d868bd52700510843ccd6 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 12 Jan 2018 00:51:52 +0900 Subject: kbuild: remove unnecessary LEX_PREFIX and YACC_PREFIX Kconfig was the only user of these. With Kconfig converted to use the default 'yy' prefix, we do not need them any more. Signed-off-by: Masahiro Yamada Reviewed-by: Ulf Magnusson --- scripts/Makefile.lib | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'scripts/Makefile.lib') diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 0f9ef3fbbaf5..5ff2761e973d 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -188,10 +188,8 @@ endef # LEX # --------------------------------------------------------------------------- -LEX_PREFIX = $(if $(LEX_PREFIX_${baseprereq}),$(LEX_PREFIX_${baseprereq}),yy) - quiet_cmd_flex = LEX $@ - cmd_flex = $(LEX) -o$@ -L -P $(LEX_PREFIX) $< + cmd_flex = $(LEX) -o$@ -L $< ifdef REGENERATE_PARSERS .PRECIOUS: $(src)/%.lex.c_shipped @@ -205,10 +203,8 @@ $(filter %.lex.c,$(targets)): $(obj)/%.lex.c: $(src)/%.l FORCE # YACC # --------------------------------------------------------------------------- -YACC_PREFIX = $(if $(YACC_PREFIX_${baseprereq}),$(YACC_PREFIX_${baseprereq}),yy) - quiet_cmd_bison = YACC $@ - cmd_bison = $(YACC) -o$@ -t -l -p $(YACC_PREFIX) $< + cmd_bison = $(YACC) -o$@ -t -l $< ifdef REGENERATE_PARSERS .PRECIOUS: $(src)/%.tab.c_shipped -- cgit v1.2.3 From f759625ad270898efdf8c153c74021a8a919312b Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 18 Jan 2018 12:31:46 +0900 Subject: kbuild: fix W= option checks for extra DTC warnings Kbuild supports 3 levels of extra warnings, and multiple levels can be combined, like W=12, W=123. It was added by commit a6de553da01c ("kbuild: Allow to combine multiple W= levels"). From the log of commit 8654cb8d0371 ("dtc: update warning settings for new bus and node/property name checks"), I assume: - unit_address_vs_reg, simple_bus_reg, etc. belong to level 1 - node_name_chars_strict, property_name_chars_strict belong to level 2 However, the level 1 warnings are displayed by any argument to W=. On the other hand, the level 2 warnings are displayed by W=2, but not by W=12, or W=123. Use $(findstring ...) like scripts/Makefile.extrawarn. Signed-off-by: Masahiro Yamada Acked-by: Arnd Bergmann --- scripts/Makefile.lib | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts/Makefile.lib') diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 1ca4dcd2d500..7dee1da83e2a 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -264,7 +264,7 @@ cmd_gzip = (cat $(filter-out FORCE,$^) | gzip -n -f -9 > $@) || \ DTC ?= $(objtree)/scripts/dtc/dtc # Disable noisy checks by default -ifeq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),) +ifeq ($(findstring 1,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) DTC_FLAGS += -Wno-unit_address_vs_reg \ -Wno-simple_bus_reg \ -Wno-unit_address_format \ @@ -273,7 +273,7 @@ DTC_FLAGS += -Wno-unit_address_vs_reg \ -Wno-pci_device_reg endif -ifeq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),2) +ifneq ($(findstring 2,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) DTC_FLAGS += -Wnode_name_chars_strict \ -Wproperty_name_chars_strict endif -- cgit v1.2.3 From 0e410e158e5baa1300bdf678cea4f4e0cf9d8b94 Mon Sep 17 00:00:00 2001 From: Andrey Konovalov Date: Tue, 6 Feb 2018 15:36:00 -0800 Subject: kasan: don't emit builtin calls when sanitization is off With KASAN enabled the kernel has two different memset() functions, one with KASAN checks (memset) and one without (__memset). KASAN uses some macro tricks to use the proper version where required. For example memset() calls in mm/slub.c are without KASAN checks, since they operate on poisoned slab object metadata. The issue is that clang emits memset() calls even when there is no memset() in the source code. They get linked with improper memset() implementation and the kernel fails to boot due to a huge amount of KASAN reports during early boot stages. The solution is to add -fno-builtin flag for files with KASAN_SANITIZE := n marker. Link: http://lkml.kernel.org/r/8ffecfffe04088c52c42b92739c2bd8a0bcb3f5e.1516384594.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Acked-by: Nick Desaulniers Cc: Masahiro Yamada Cc: Michal Marek Cc: Andrey Ryabinin Cc: Alexander Potapenko Cc: Dmitry Vyukov Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Makefile | 3 ++- scripts/Makefile.kasan | 3 +++ scripts/Makefile.lib | 2 +- 3 files changed, 6 insertions(+), 2 deletions(-) (limited to 'scripts/Makefile.lib') diff --git a/Makefile b/Makefile index 11aff0f9e105..0d49ff4022fb 100644 --- a/Makefile +++ b/Makefile @@ -434,7 +434,8 @@ export MAKE LEX YACC AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS -export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_KASAN CFLAGS_UBSAN +export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE +export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL diff --git a/scripts/Makefile.kasan b/scripts/Makefile.kasan index 1ce7115aa499..94c9e65cc83a 100644 --- a/scripts/Makefile.kasan +++ b/scripts/Makefile.kasan @@ -31,4 +31,7 @@ else endif CFLAGS_KASAN += $(call cc-option, -fsanitize-address-use-after-scope) + +CFLAGS_KASAN_NOSANITIZE := -fno-builtin + endif diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 5fdc1a19b02c..5589bae34af6 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -121,7 +121,7 @@ endif ifeq ($(CONFIG_KASAN),y) _c_flags += $(if $(patsubst n%,, \ $(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \ - $(CFLAGS_KASAN)) + $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE)) endif ifeq ($(CONFIG_UBSAN),y) -- cgit v1.2.3