From 622445541b751ce70a952b8486ce4512a792c0a2 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 25 Jul 2019 17:05:13 +0900 Subject: [PATCH 1/9] kbuild: detect missing "WITH Linux-syscall-note" for uapi headers UAPI headers licensed under GPL are supposed to have exception "WITH Linux-syscall-note" so that they can be included into non-GPL user space application code. Unfortunately, people often miss to add it. Break 'make headers' when any of exported headers lacks the exception note so that the 0-day bot can easily catch it. Signed-off-by: Masahiro Yamada --- scripts/headers_install.sh | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/scripts/headers_install.sh b/scripts/headers_install.sh index 47f6f3ea0771..bbaf29386995 100755 --- a/scripts/headers_install.sh +++ b/scripts/headers_install.sh @@ -23,6 +23,12 @@ TMPFILE=$OUTFILE.tmp trap 'rm -f $OUTFILE $TMPFILE' EXIT +# SPDX-License-Identifier with GPL variants must have "WITH Linux-syscall-note" +if [ -n "$(sed -n -e "/SPDX-License-Identifier:.*GPL-/{/WITH Linux-syscall-note/!p}" $INFILE)" ]; then + echo "error: $INFILE: missing \"WITH Linux-syscall-note\" for SPDX-License-Identifier" >&2 + exit 1 +fi + sed -E -e ' s/([[:space:](])(__user|__force|__iomem)[[:space:]]/\1/g s/__attribute_const__([[:space:]]|$)/\1/g From 5241ab4cf42d3a93b933b55d3d53f43049081fa1 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 29 Jul 2019 18:15:17 +0900 Subject: [PATCH 2/9] kbuild: initialize CLANG_FLAGS correctly in the top Makefile CLANG_FLAGS is initialized by the following line: CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%)) ..., which is run only when CROSS_COMPILE is set. Some build targets (bindeb-pkg etc.) recurse to the top Makefile. When you build the kernel with Clang but without CROSS_COMPILE, the same compiler flags such as -no-integrated-as are accumulated into CLANG_FLAGS. If you run 'make CC=clang' and then 'make CC=clang bindeb-pkg', Kbuild will recompile everything needlessly due to the build command change. Fix this by correctly initializing CLANG_FLAGS. Fixes: 238bcbc4e07f ("kbuild: consolidate Clang compiler flags") Cc: # v5.0+ Signed-off-by: Masahiro Yamada Reviewed-by: Nathan Chancellor Acked-by: Nick Desaulniers --- Makefile | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/Makefile b/Makefile index fa0fbe7851ea..5ee6f6889869 100644 --- a/Makefile +++ b/Makefile @@ -472,6 +472,7 @@ KBUILD_CFLAGS_MODULE := -DMODULE KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds KBUILD_LDFLAGS := GCC_PLUGINS_CFLAGS := +CLANG_FLAGS := export ARCH SRCARCH CONFIG_SHELL HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC export CPP AR NM STRIP OBJCOPY OBJDUMP PAHOLE KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS @@ -519,7 +520,7 @@ endif ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),) ifneq ($(CROSS_COMPILE),) -CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%)) +CLANG_FLAGS += --target=$(notdir $(CROSS_COMPILE:%-=%)) GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit)) CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR) GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..) From 944cfe9be1fbbec73bab2f7e77fe2e8f9c72970f Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 31 Jul 2019 00:58:59 +0900 Subject: [PATCH 3/9] kbuild: modpost: include .*.cmd files only when targets exist If a build rule fails, the .DELETE_ON_ERROR special target removes the target, but does nothing for the .*.cmd file, which might be corrupted. So, .*.cmd files should be included only when the corresponding targets exist. Commit 392885ee82d3 ("kbuild: let fixdep directly write to .*.cmd files") missed to fix up this file. Fixes: 392885ee82d3 ("kbuild: let fixdep directly write to .*.cmd") Cc: # v5.0+ Signed-off-by: Masahiro Yamada --- scripts/Makefile.modpost | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index 6b19c1a4eae5..ad4b9829a456 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -145,10 +145,8 @@ FORCE: # optimization, we don't need to read them if the target does not # exist, we will rebuild anyway in that case. -cmd_files := $(wildcard $(foreach f,$(sort $(targets)),$(dir $(f)).$(notdir $(f)).cmd)) +existing-targets := $(wildcard $(sort $(targets))) -ifneq ($(cmd_files),) - include $(cmd_files) -endif +-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd) .PHONY: $(PHONY) From cb4819934a7f9b87876f11ed05b8624c0114551b Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 31 Jul 2019 00:59:00 +0900 Subject: [PATCH 4/9] kbuild: modpost: handle KBUILD_EXTRA_SYMBOLS only for external modules KBUILD_EXTRA_SYMBOLS makes sense only when building external modules. Moreover, the modpost sets 'external_module' if the -e option is given. I replaced $(patsubst %, -e %,...) with simpler $(addprefix -e,...) while I was here. Signed-off-by: Masahiro Yamada --- scripts/Makefile.modpost | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index ad4b9829a456..c856512349cd 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -78,7 +78,7 @@ modpost = scripts/mod/modpost \ $(if $(CONFIG_MODULE_SRCVERSION_ALL),-a,) \ $(if $(KBUILD_EXTMOD),-i,-o) $(kernelsymfile) \ $(if $(KBUILD_EXTMOD),-I $(modulesymfile)) \ - $(if $(KBUILD_EXTRA_SYMBOLS), $(patsubst %, -e %,$(KBUILD_EXTRA_SYMBOLS))) \ + $(if $(KBUILD_EXTMOD),$(addprefix -e ,$(KBUILD_EXTRA_SYMBOLS))) \ $(if $(KBUILD_EXTMOD),-o $(modulesymfile)) \ $(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \ $(if $(KBUILD_MODPOST_WARN),-w) From acf2a1397a686365775385ed4657941119172263 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 31 Jul 2019 00:59:01 +0900 Subject: [PATCH 5/9] kbuild: modpost: remove unnecessary dependency for __modpost __modpost is a phony target. The dependency on FORCE is pointless. All the objects have been built in the previous stage, so the dependency on the objects are not necessary either. Count the number of modules in a more straightforward way. Signed-off-by: Masahiro Yamada --- scripts/Makefile.modpost | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index c856512349cd..fdab32d6f552 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -86,11 +86,11 @@ modpost = scripts/mod/modpost \ MODPOST_OPT=$(subst -i,-n,$(filter -i,$(MAKEFLAGS))) # We can go over command line length here, so be careful. -quiet_cmd_modpost = MODPOST $(words $(filter-out vmlinux FORCE, $^)) modules +quiet_cmd_modpost = MODPOST $(words $(modules)) modules cmd_modpost = sed 's/ko$$/o/' $(modorder) | $(modpost) $(MODPOST_OPT) -s -T - PHONY += __modpost -__modpost: $(modules:.ko=.o) FORCE +__modpost: $(call cmd,modpost) $(wildcard vmlinux) quiet_cmd_kernel-mod = MODPOST $@ From a721588d9475cbbf9e8b3ae1a69b1dea88d01653 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 31 Jul 2019 00:59:02 +0900 Subject: [PATCH 6/9] kbuild: modpost: do not parse unnecessary rules for vmlinux modpost Since commit ff9b45c55b26 ("kbuild: modpost: read modules.order instead of $(MODVERDIR)/*.mod"), 'make vmlinux' emits a warning, like this: $ make defconfig vmlinux [ snip ] LD vmlinux.o cat: modules.order: No such file or directory MODPOST vmlinux.o MODINFO modules.builtin.modinfo KSYM .tmp_kallsyms1.o KSYM .tmp_kallsyms2.o LD vmlinux SORTEX vmlinux SYSMAP System.map When building only vmlinux, KBUILD_MODULES is not set. Hence, the modules.order is not generated. For the vmlinux modpost, it is not necessary at all. Separate scripts/Makefile.modpost for the vmlinux/modules stages. This works more efficiently because the vmlinux modpost does not need to include .*.cmd files. Fixes: ff9b45c55b26 ("kbuild: modpost: read modules.order instead of $(MODVERDIR)/*.mod") Signed-off-by: Masahiro Yamada --- scripts/Makefile.modpost | 74 ++++++++++++++++++++++------------------ scripts/link-vmlinux.sh | 2 +- 2 files changed, 41 insertions(+), 35 deletions(-) diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index fdab32d6f552..92ed02d7cd5e 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -38,12 +38,39 @@ # symbols in the final module linking stage # KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. # This is solely useful to speed up test compiles -PHONY := _modpost -_modpost: __modpost + +PHONY := __modpost +__modpost: include include/config/auto.conf include scripts/Kbuild.include +kernelsymfile := $(objtree)/Module.symvers +modulesymfile := $(firstword $(KBUILD_EXTMOD))/Module.symvers + +MODPOST = scripts/mod/modpost \ + $(if $(CONFIG_MODVERSIONS),-m) \ + $(if $(CONFIG_MODULE_SRCVERSION_ALL),-a) \ + $(if $(KBUILD_EXTMOD),-i,-o) $(kernelsymfile) \ + $(if $(KBUILD_EXTMOD),-I $(modulesymfile)) \ + $(if $(KBUILD_EXTMOD),$(addprefix -e ,$(KBUILD_EXTRA_SYMBOLS))) \ + $(if $(KBUILD_EXTMOD),-o $(modulesymfile)) \ + $(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \ + $(if $(KBUILD_MODPOST_WARN),-w) + +ifdef MODPOST_VMLINUX + +__modpost: vmlinux.o + +quiet_cmd_modpost = MODPOST $@ + cmd_modpost = $(MODPOST) $@ + +PHONY += vmlinux.o +vmlinux.o: + $(call cmd,modpost) + +else + # When building external modules load the Kbuild file to retrieve EXTRA_SYMBOLS info ifneq ($(KBUILD_EXTMOD),) @@ -58,50 +85,27 @@ endif include scripts/Makefile.lib -kernelsymfile := $(objtree)/Module.symvers -modulesymfile := $(firstword $(KBUILD_EXTMOD))/Module.symvers - modorder := $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)modules.order -# Step 1), find all modules listed in modules.order -ifdef CONFIG_MODULES +# find all modules listed in modules.order modules := $(sort $(shell cat $(modorder))) -endif # Stop after building .o files if NOFINAL is set. Makes compile tests quicker -_modpost: $(if $(KBUILD_MODPOST_NOFINAL), $(modules:.ko:.o),$(modules)) +__modpost: $(if $(KBUILD_MODPOST_NOFINAL), $(modules:.ko:.o),$(modules)) + @: -# Step 2), invoke modpost -# Includes step 3,4 -modpost = scripts/mod/modpost \ - $(if $(CONFIG_MODVERSIONS),-m) \ - $(if $(CONFIG_MODULE_SRCVERSION_ALL),-a,) \ - $(if $(KBUILD_EXTMOD),-i,-o) $(kernelsymfile) \ - $(if $(KBUILD_EXTMOD),-I $(modulesymfile)) \ - $(if $(KBUILD_EXTMOD),$(addprefix -e ,$(KBUILD_EXTRA_SYMBOLS))) \ - $(if $(KBUILD_EXTMOD),-o $(modulesymfile)) \ - $(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \ - $(if $(KBUILD_MODPOST_WARN),-w) - -MODPOST_OPT=$(subst -i,-n,$(filter -i,$(MAKEFLAGS))) +MODPOST += $(subst -i,-n,$(filter -i,$(MAKEFLAGS))) -s -T - $(wildcard vmlinux) # We can go over command line length here, so be careful. quiet_cmd_modpost = MODPOST $(words $(modules)) modules - cmd_modpost = sed 's/ko$$/o/' $(modorder) | $(modpost) $(MODPOST_OPT) -s -T - + cmd_modpost = sed 's/ko$$/o/' $(modorder) | $(MODPOST) -PHONY += __modpost -__modpost: - $(call cmd,modpost) $(wildcard vmlinux) - -quiet_cmd_kernel-mod = MODPOST $@ - cmd_kernel-mod = $(modpost) $@ - -vmlinux.o: FORCE - $(call cmd,kernel-mod) +PHONY += modules-modpost +modules-modpost: + $(call cmd,modpost) # Declare generated files as targets for modpost -$(modules:.ko=.mod.c): __modpost ; - +$(modules:.ko=.mod.c): modules-modpost # Step 5), compile all *.mod.c files @@ -149,4 +153,6 @@ existing-targets := $(wildcard $(sort $(targets))) -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd) +endif + .PHONY: $(PHONY) diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index a7124f895b24..915775eb2921 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -210,7 +210,7 @@ info LD vmlinux.o modpost_link vmlinux.o # modpost vmlinux.o to check for section mismatches -${MAKE} -f "${srctree}/scripts/Makefile.modpost" vmlinux.o +${MAKE} -f "${srctree}/scripts/Makefile.modpost" MODPOST_VMLINUX=1 info MODINFO modules.builtin.modinfo ${OBJCOPY} -j .modinfo -O binary vmlinux.o modules.builtin.modinfo From e2a280d28d32d2cf7eaa2b1cecefd079b24c0245 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 31 Jul 2019 01:40:42 +0900 Subject: [PATCH 7/9] lib/raid6: fix unnecessary rebuild of vpermxor*.c The following four files are every time rebuilt: UNROLL lib/raid6/vpermxor1.c UNROLL lib/raid6/vpermxor2.c UNROLL lib/raid6/vpermxor4.c UNROLL lib/raid6/vpermxor8.c Fix the suffixes in the targets. Fixes: 72ad21075df8 ("lib/raid6: refactor unroll rules with pattern rules") Signed-off-by: Masahiro Yamada --- lib/raid6/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/raid6/Makefile b/lib/raid6/Makefile index 42695bc8d451..0083b5cc646c 100644 --- a/lib/raid6/Makefile +++ b/lib/raid6/Makefile @@ -66,7 +66,7 @@ CFLAGS_vpermxor1.o += $(altivec_flags) CFLAGS_vpermxor2.o += $(altivec_flags) CFLAGS_vpermxor4.o += $(altivec_flags) CFLAGS_vpermxor8.o += $(altivec_flags) -targets += vpermxor1.o vpermxor2.o vpermxor4.o vpermxor8.o +targets += vpermxor1.c vpermxor2.c vpermxor4.c vpermxor8.c $(obj)/vpermxor%.c: $(src)/vpermxor.uc $(src)/unroll.awk FORCE $(call if_changed,unroll) From e8de12fb7cde2c85bc31097cd098da79a4818305 Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Tue, 30 Jul 2019 09:48:03 -0700 Subject: [PATCH 8/9] kbuild: Check for unknown options with cc-option usage in Kconfig and clang If the particular version of clang a user has doesn't enable -Werror=unknown-warning-option by default, even though it is the default[1], then make sure to pass the option to the Kconfig cc-option command so that testing options from Kconfig files works properly. Otherwise, depending on the default values setup in the clang toolchain we will silently assume options such as -Wmaybe-uninitialized are supported by clang, when they really aren't. A compilation issue only started happening for me once commit 589834b3a009 ("kbuild: Add -Werror=unknown-warning-option to CLANG_FLAGS") was applied on top of commit b303c6df80c9 ("kbuild: compute false-positive -Wmaybe-uninitialized cases in Kconfig"). This leads kbuild to try and test for the existence of the -Wmaybe-uninitialized flag with the cc-option command in scripts/Kconfig.include, and it doesn't see an error returned from the option test so it sets the config value to Y. Then the Makefile tries to pass the unknown option on the command line and -Werror=unknown-warning-option catches the invalid option and breaks the build. Before commit 589834b3a009 ("kbuild: Add -Werror=unknown-warning-option to CLANG_FLAGS") the build works fine, but any cc-option test of a warning option in Kconfig files silently evaluates to true, even if the warning option flag isn't supported on clang. Note: This doesn't change cc-option usages in Makefiles because those use a different rule that includes KBUILD_CFLAGS by default (see the __cc-option command in scripts/Kbuild.incluide). The KBUILD_CFLAGS variable already has the -Werror=unknown-warning-option flag set. Thanks to Doug for pointing out the different rule. [1] https://clang.llvm.org/docs/DiagnosticsReference.html#wunknown-warning-option Cc: Peter Smith Cc: Nick Desaulniers Cc: Douglas Anderson Signed-off-by: Stephen Boyd Reviewed-by: Nathan Chancellor Signed-off-by: Masahiro Yamada --- scripts/Kconfig.include | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include index 8a5c4d645eb1..4bbf4fc163a2 100644 --- a/scripts/Kconfig.include +++ b/scripts/Kconfig.include @@ -25,7 +25,7 @@ failure = $(if-success,$(1),n,y) # $(cc-option,) # Return y if the compiler supports , n otherwise -cc-option = $(success,$(CC) -Werror $(1) -E -x c /dev/null -o /dev/null) +cc-option = $(success,$(CC) -Werror $(CLANG_FLAGS) $(1) -E -x c /dev/null -o /dev/null) # $(ld-option,) # Return y if the linker supports , n otherwise From 0c5b6c28ed68becb692b43eae5e44d5aa7e160ce Mon Sep 17 00:00:00 2001 From: "M. Vefa Bicakci" Date: Sat, 3 Aug 2019 06:02:12 -0400 Subject: [PATCH 9/9] kconfig: Clear "written" flag to avoid data loss Prior to this commit, starting nconfig, xconfig or gconfig, and saving the .config file more than once caused data loss, where a .config file that contained only comments would be written to disk starting from the second save operation. This bug manifests itself because the SYMBOL_WRITTEN flag is never cleared after the first call to conf_write, and subsequent calls to conf_write then skip all of the configuration symbols due to the SYMBOL_WRITTEN flag being set. This commit resolves this issue by clearing the SYMBOL_WRITTEN flag from all symbols before conf_write returns. Fixes: 8e2442a5f86e ("kconfig: fix missing choice values in auto.conf") Cc: linux-stable # 4.19+ Signed-off-by: M. Vefa Bicakci Signed-off-by: Masahiro Yamada --- scripts/kconfig/confdata.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c index 1134892599da..3569d2dec37c 100644 --- a/scripts/kconfig/confdata.c +++ b/scripts/kconfig/confdata.c @@ -848,6 +848,7 @@ int conf_write(const char *name) const char *str; char tmpname[PATH_MAX + 1], oldname[PATH_MAX + 1]; char *env; + int i; bool need_newline = false; if (!name) @@ -930,6 +931,9 @@ next: } fclose(out); + for_all_symbols(i, sym) + sym->flags &= ~SYMBOL_WRITTEN; + if (*tmpname) { if (is_same(name, tmpname)) { conf_message("No change to %s", name);