From 4bf73588165ba7d32131a043775557a54b6e1db5 Mon Sep 17 00:00:00 2001 From: Dmitry Goncharov Date: Mon, 5 Dec 2022 16:48:19 -0500 Subject: kbuild: Port silent mode detection to future gnu make. Port silent mode detection to the future (post make-4.4) versions of gnu make. Makefile contains the following piece of make code to detect if option -s is specified on the command line. ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),) This code is executed by make at parse time and assumes that MAKEFLAGS does not contain command line variable definitions. Currently if the user defines a=s on the command line, then at build only time MAKEFLAGS contains " -- a=s". However, starting with commit dc2d963989b96161472b2cd38cef5d1f4851ea34 MAKEFLAGS contains command line definitions at both parse time and build time. This '-s' detection code then confuses a command line variable definition which contains letter 's' with option -s. $ # old make $ make net/wireless/ocb.o a=s CALL scripts/checksyscalls.sh DESCEND objtool $ # this a new make which defines makeflags at parse time $ ~/src/gmake/make/l64/make net/wireless/ocb.o a=s $ We can see here that the letter 's' from 'a=s' was confused with -s. This patch checks for presence of -s using a method recommended by the make manual here https://www.gnu.org/software/make/manual/make.html#Testing-Flags. Link: https://lists.gnu.org/archive/html/bug-make/2022-11/msg00190.html Reported-by: Jan Palus Signed-off-by: Dmitry Goncharov Signed-off-by: Masahiro Yamada --- Makefile | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index 6f846b1f2618..fbd9ff4a61e7 100644 --- a/Makefile +++ b/Makefile @@ -93,10 +93,17 @@ endif # If the user is running make -s (silent mode), suppress echoing of # commands +# make-4.0 (and later) keep single letter options in the 1st word of MAKEFLAGS. -ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),) - quiet=silent_ - KBUILD_VERBOSE = 0 +ifeq ($(filter 3.%,$(MAKE_VERSION)),) +silence:=$(findstring s,$(firstword -$(MAKEFLAGS))) +else +silence:=$(findstring s,$(filter-out --%,$(MAKEFLAGS))) +endif + +ifeq ($(silence),s) +quiet=silent_ +KBUILD_VERBOSE = 0 endif export quiet Q KBUILD_VERBOSE -- cgit v1.2.3 From efa80b028c7a9c74fd875517aa0fc9fd8d610ed0 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 6 Dec 2022 13:07:30 +0900 Subject: kbuild: move -Werror from KBUILD_CFLAGS to KBUILD_CPPFLAGS CONFIG_WERROR turns warnings into errors, which happens only for *.c files because -Werror is added to KBUILD_CFLAGS. Adding it to KBUILD_CPPFLAGS makes more sense because preprocessors understand the -Werror option. For example, you can put a #warning directive in any preprocessed code. warning: #warning "this is a warning message" [-Wcpp] If -Werror is added, it is promoted to an error. error: #warning "this is a warning message" [-Werror=cpp] This commit moves -Werror to KBUILD_CPPFLAGS so it works in the same way for *.c, *.S, *.lds.S or whatever needs preprocessing. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers Reviewed-by: Nathan Chancellor --- Makefile | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index fbd9ff4a61e7..6b047daa46cc 100644 --- a/Makefile +++ b/Makefile @@ -866,7 +866,8 @@ stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG) := -fstack-protector-strong KBUILD_CFLAGS += $(stackp-flags-y) -KBUILD_CFLAGS-$(CONFIG_WERROR) += -Werror +KBUILD_CPPFLAGS-$(CONFIG_WERROR) += -Werror +KBUILD_CPPFLAGS += $(KBUILD_CPPFLAGS-y) KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings -- cgit v1.2.3 From fccb3d3eda8d19b893e1fd18e8c70b78784b2a72 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 11 Dec 2022 11:46:47 +0900 Subject: kbuild: add test-{ge,gt,le,lt} macros GNU Make 4.4 introduced $(intcmp ...), which is useful to compare two integers without forking a new process. Add test-{ge,gt,le,lt} macros, which work more efficiently with GNU Make >= 4.4. For older Make versions, they fall back to the 'test' shell command. The first two parameters to $(intcmp ...) must not be empty. To avoid the syntax error, I appended '0' to them. Fortunately, '00' is treated as '0'. This is needed because CONFIG options may expand to an empty string when the kernel configuration is not included. Signed-off-by: Masahiro Yamada Acked-by: Palmer Dabbelt # RISC-V Reviewed-by: Nathan Chancellor Reviewed-by: Nicolas Schier --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index 6b047daa46cc..ff36288ae671 100644 --- a/Makefile +++ b/Makefile @@ -994,7 +994,7 @@ KBUILD_LDFLAGS += -mllvm -import-instr-limit=5 # Check for frame size exceeding threshold during prolog/epilog insertion # when using lld < 13.0.0. ifneq ($(CONFIG_FRAME_WARN),0) -ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0) +ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y) KBUILD_LDFLAGS += -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN) endif endif -- cgit v1.2.3 From 6768fa4bcb6c1618248f135d04b9287ba2724ae0 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 11 Dec 2022 11:54:47 +0900 Subject: kbuild: add read-file macro Since GNU Make 4.2, $(file ...) supports the read operater '<', which is useful to read a file without forking a new process. No warning is shown even if the input file is missing. For older Make versions, it falls back to the cat command. Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier Reviewed-by: Alexander Lobakin Tested-by: Alexander Lobakin --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index ff36288ae671..591485152a95 100644 --- a/Makefile +++ b/Makefile @@ -376,7 +376,7 @@ else # !mixed-build include $(srctree)/scripts/Kbuild.include # Read KERNELRELEASE from include/config/kernel.release (if it exists) -KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null) +KERNELRELEASE = $(call read-file, include/config/kernel.release) KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION) export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION -- cgit v1.2.3 From f65a486821cfd363833079b2a7b0769250ee21c9 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 11 Dec 2022 22:04:07 +0900 Subject: kbuild: change module.order to list *.o instead of *.ko scripts/Makefile.build replaces the suffix .o with .ko, then scripts/Makefile.modpost calls the sed command to change .ko back to the original .o suffix. Instead of converting the suffixes back-and-forth, store the .o paths in modules.order, and replace it with .ko in 'make modules_install'. This avoids the unneeded sed command. Signed-off-by: Masahiro Yamada Reviewed-by: Luis Chamberlain --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index 591485152a95..f506879e7452 100644 --- a/Makefile +++ b/Makefile @@ -1564,7 +1564,7 @@ __modinst_pre: rm -f $(MODLIB)/build ; \ ln -s $(CURDIR) $(MODLIB)/build ; \ fi - @sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order + @sed 's:^\(.*\)\.o$$:kernel/\1.ko:' modules.order > $(MODLIB)/modules.order @cp -f modules.builtin $(MODLIB)/ @cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/ -- cgit v1.2.3 From 87d599fc3955e59b1ed30f350321a4be5353f945 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 13 Dec 2022 20:24:20 +0900 Subject: kbuild: ensure Make >= 3.82 is used Documentation/process/changes.rst notes the minimal GNU Make version, but it is not checked anywhere. We could check $(MAKE_VERSION), but another simple way is to check $(.FEATURES) since the feature list always grows. GNU Make 3.81 expands $(.FEATURES) to: target-specific order-only second-expansion else-if archives jobserver check-symlink GNU Make 3.82 expands $(.FEATURES) to: target-specific order-only second-expansion else-if shortest-stem undefine archives jobserver check-symlink To ensure Make >= 3.82, you can check either 'shortest-stem' or 'undefine'. This way is not always possible. For example, Make 4.0 through 4.2 have the same set of $(.FEATURES). At that point, we will need to come up with a different approach. Signed-off-by: Masahiro Yamada Reviewed-by: Nathan Chancellor Reviewed-by: Nicolas Schier --- Makefile | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'Makefile') diff --git a/Makefile b/Makefile index f506879e7452..5f015f206e12 100644 --- a/Makefile +++ b/Makefile @@ -11,6 +11,10 @@ NAME = Hurr durr I'ma ninja sloth # Comments in this file are targeted only to the developer, do not # expect to learn how to build the kernel reading this file. +ifeq ($(filter undefine,$(.FEATURES)),) +$(error GNU Make >= 3.82 is required. Your Make version is $(MAKE_VERSION)) +endif + $(if $(filter __%, $(MAKECMDGOALS)), \ $(error targets prefixed with '__' are only for internal use)) -- cgit v1.2.3