From 989ceac799cb28a477304cdc9ee72995191c6378 Mon Sep 17 00:00:00 2001 From: Nick Desaulniers Date: Thu, 12 Aug 2021 11:38:48 -0700 Subject: x86/build: Remove stale cc-option checks cc-option, __cc-option, cc-option-yn, and cc-disable-warning all invoke the compiler during build time, and can slow down the build when these checks become stale for our supported compilers, whose minimally supported versions increases over time. See Documentation/process/changes.rst for the current supported minimal versions (GCC 4.9+, clang 10.0.1+). Compiler version support for these flags may be verified on godbolt.org. The following flags are supported by all supported versions of GCC and Clang. Remove their cc-option, __cc-option, and cc-option-yn tests. -Wno-address-of-packed-member -mno-avx -m32 -mno-80387 -march=k8 -march=nocona -march=core2 -march=atom -mtune=generic -mfentry [ mingo: Fixed regression on GCC, via partial revert of the stack-boundary changes. ] Signed-off-by: Nick Desaulniers Signed-off-by: Borislav Petkov Signed-off-by: Ingo Molnar Link: https://github.com/ClangBuiltLinux/linux/issues/1436 Link: https://lkml.kernel.org/r/20210812183848.1519994-1-ndesaulniers@google.com --- arch/x86/Makefile | 46 ++++++++++++++-------------------------------- 1 file changed, 14 insertions(+), 32 deletions(-) diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 307fd0000a83..88fb2bca6a3e 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -31,8 +31,8 @@ REALMODE_CFLAGS := -m16 -g -Os -DDISABLE_BRANCH_PROFILING \ REALMODE_CFLAGS += -ffreestanding REALMODE_CFLAGS += -fno-stack-protector -REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -Wno-address-of-packed-member) -REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), $(cc_stack_align4)) +REALMODE_CFLAGS += -Wno-address-of-packed-member +REALMODE_CFLAGS += $(cc_stack_align4) REALMODE_CFLAGS += $(CLANG_FLAGS) export REALMODE_CFLAGS @@ -48,8 +48,7 @@ export BITS # # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383 # -KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow -KBUILD_CFLAGS += $(call cc-option,-mno-avx,) +KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow -mno-avx # Intel CET isn't enabled in the kernel KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none) @@ -59,9 +58,8 @@ ifeq ($(CONFIG_X86_32),y) UTS_MACHINE := i386 CHECKFLAGS += -D__i386__ - biarch := $(call cc-option,-m32) - KBUILD_AFLAGS += $(biarch) - KBUILD_CFLAGS += $(biarch) + KBUILD_AFLAGS += -m32 + KBUILD_CFLAGS += -m32 KBUILD_CFLAGS += -msoft-float -mregparm=3 -freg-struct-return @@ -72,7 +70,7 @@ ifeq ($(CONFIG_X86_32),y) # Align the stack to the register width instead of using the default # alignment of 16 bytes. This reduces stack usage and the number of # alignment instructions. - KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align4)) + KBUILD_CFLAGS += $(cc_stack_align4) # CPU-specific tuning. Anything which can be shared with UML should go here. include arch/x86/Makefile_32.cpu @@ -93,7 +91,6 @@ else UTS_MACHINE := x86_64 CHECKFLAGS += -D__x86_64__ - biarch := -m64 KBUILD_AFLAGS += -m64 KBUILD_CFLAGS += -m64 @@ -104,7 +101,7 @@ else KBUILD_CFLAGS += $(call cc-option,-falign-loops=1) # Don't autogenerate traditional x87 instructions - KBUILD_CFLAGS += $(call cc-option,-mno-80387) + KBUILD_CFLAGS += -mno-80387 KBUILD_CFLAGS += $(call cc-option,-mno-fp-ret-in-387) # By default gcc and clang use a stack alignment of 16 bytes for x86. @@ -114,20 +111,17 @@ else # default alignment which keep the stack *mis*aligned. # Furthermore an alignment to the register width reduces stack usage # and the number of alignment instructions. - KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align8)) + KBUILD_CFLAGS += $(cc_stack_align8) # Use -mskip-rax-setup if supported. KBUILD_CFLAGS += $(call cc-option,-mskip-rax-setup) # FIXME - should be integrated in Makefile.cpu (Makefile_32.cpu) - cflags-$(CONFIG_MK8) += $(call cc-option,-march=k8) - cflags-$(CONFIG_MPSC) += $(call cc-option,-march=nocona) - - cflags-$(CONFIG_MCORE2) += \ - $(call cc-option,-march=core2,$(call cc-option,-mtune=generic)) - cflags-$(CONFIG_MATOM) += $(call cc-option,-march=atom) \ - $(call cc-option,-mtune=atom,$(call cc-option,-mtune=generic)) - cflags-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=generic) + cflags-$(CONFIG_MK8) += -march=k8 + cflags-$(CONFIG_MPSC) += -march=nocona + cflags-$(CONFIG_MCORE2) += -march=core2 + cflags-$(CONFIG_MATOM) += -march=atom + cflags-$(CONFIG_GENERIC_CPU) += -mtune=generic KBUILD_CFLAGS += $(cflags-y) KBUILD_CFLAGS += -mno-red-zone @@ -158,18 +152,6 @@ export CONFIG_X86_X32_ABI ifdef CONFIG_FUNCTION_GRAPH_TRACER ifndef CONFIG_HAVE_FENTRY ACCUMULATE_OUTGOING_ARGS := 1 - else - ifeq ($(call cc-option-yn, -mfentry), n) - ACCUMULATE_OUTGOING_ARGS := 1 - - # GCC ignores '-maccumulate-outgoing-args' when used with '-Os'. - # If '-Os' is enabled, disable it and print a warning. - ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE - undefine CONFIG_CC_OPTIMIZE_FOR_SIZE - $(warning Disabling CONFIG_CC_OPTIMIZE_FOR_SIZE. Your compiler does not have -mfentry so you cannot optimize for size with CONFIG_FUNCTION_GRAPH_TRACER.) - endif - - endif endif endif @@ -193,7 +175,7 @@ ifdef CONFIG_RETPOLINE # only been fixed starting from gcc stable version 8.4.0 and # onwards, but not for older ones. See gcc bug #86952. ifndef CONFIG_CC_IS_CLANG - KBUILD_CFLAGS += $(call cc-option,-fno-jump-tables) + KBUILD_CFLAGS += -fno-jump-tables endif endif -- cgit 1.4.1 From 03dca99e200f4d268f70079cf54e3b1200c9eb9d Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Fri, 25 Jun 2021 17:10:16 +0200 Subject: x86/tools/relocs: Mark die() with the printf function attr format Mark die() as a function which accepts printf-style arguments so that the compiler can typecheck them against the supplied format string. Use the C99 inttypes.h format specifiers as relocs.c gets built for both 32- and 64-bit. Original version of the patch by Greg Kroah-Hartman Signed-off-by: Borislav Petkov Reviewed-by: Greg Kroah-Hartman Link: http://lkml.kernel.org/r/YNnb6Q4QHtNYC049@zn.tnic --- arch/x86/tools/relocs.c | 37 ++++++++++++++++++++----------------- arch/x86/tools/relocs.h | 1 + 2 files changed, 21 insertions(+), 17 deletions(-) diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c index 9ba700dc47de..27c82207d387 100644 --- a/arch/x86/tools/relocs.c +++ b/arch/x86/tools/relocs.c @@ -26,6 +26,9 @@ static struct relocs relocs32; #if ELF_BITS == 64 static struct relocs relocs32neg; static struct relocs relocs64; +#define FMT PRIu64 +#else +#define FMT PRIu32 #endif struct section { @@ -389,7 +392,7 @@ static void read_ehdr(FILE *fp) Elf_Shdr shdr; if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) - die("Seek to %d failed: %s\n", ehdr.e_shoff, strerror(errno)); + die("Seek to %" FMT " failed: %s\n", ehdr.e_shoff, strerror(errno)); if (fread(&shdr, sizeof(shdr), 1, fp) != 1) die("Cannot read initial ELF section header: %s\n", strerror(errno)); @@ -412,17 +415,17 @@ static void read_shdrs(FILE *fp) secs = calloc(shnum, sizeof(struct section)); if (!secs) { - die("Unable to allocate %d section headers\n", + die("Unable to allocate %ld section headers\n", shnum); } if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) { - die("Seek to %d failed: %s\n", - ehdr.e_shoff, strerror(errno)); + die("Seek to %" FMT " failed: %s\n", + ehdr.e_shoff, strerror(errno)); } for (i = 0; i < shnum; i++) { struct section *sec = &secs[i]; if (fread(&shdr, sizeof(shdr), 1, fp) != 1) - die("Cannot read ELF section headers %d/%d: %s\n", + die("Cannot read ELF section headers %d/%ld: %s\n", i, shnum, strerror(errno)); sec->shdr.sh_name = elf_word_to_cpu(shdr.sh_name); sec->shdr.sh_type = elf_word_to_cpu(shdr.sh_type); @@ -450,12 +453,12 @@ static void read_strtabs(FILE *fp) } sec->strtab = malloc(sec->shdr.sh_size); if (!sec->strtab) { - die("malloc of %d bytes for strtab failed\n", - sec->shdr.sh_size); + die("malloc of %" FMT " bytes for strtab failed\n", + sec->shdr.sh_size); } if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) { - die("Seek to %d failed: %s\n", - sec->shdr.sh_offset, strerror(errno)); + die("Seek to %" FMT " failed: %s\n", + sec->shdr.sh_offset, strerror(errno)); } if (fread(sec->strtab, 1, sec->shdr.sh_size, fp) != sec->shdr.sh_size) { @@ -475,12 +478,12 @@ static void read_symtabs(FILE *fp) } sec->symtab = malloc(sec->shdr.sh_size); if (!sec->symtab) { - die("malloc of %d bytes for symtab failed\n", - sec->shdr.sh_size); + die("malloc of %" FMT " bytes for symtab failed\n", + sec->shdr.sh_size); } if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) { - die("Seek to %d failed: %s\n", - sec->shdr.sh_offset, strerror(errno)); + die("Seek to %" FMT " failed: %s\n", + sec->shdr.sh_offset, strerror(errno)); } if (fread(sec->symtab, 1, sec->shdr.sh_size, fp) != sec->shdr.sh_size) { @@ -508,12 +511,12 @@ static void read_relocs(FILE *fp) } sec->reltab = malloc(sec->shdr.sh_size); if (!sec->reltab) { - die("malloc of %d bytes for relocs failed\n", - sec->shdr.sh_size); + die("malloc of %" FMT " bytes for relocs failed\n", + sec->shdr.sh_size); } if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) { - die("Seek to %d failed: %s\n", - sec->shdr.sh_offset, strerror(errno)); + die("Seek to %" FMT " failed: %s\n", + sec->shdr.sh_offset, strerror(errno)); } if (fread(sec->reltab, 1, sec->shdr.sh_size, fp) != sec->shdr.sh_size) { diff --git a/arch/x86/tools/relocs.h b/arch/x86/tools/relocs.h index 43c83c0fd22c..4c49c82446eb 100644 --- a/arch/x86/tools/relocs.h +++ b/arch/x86/tools/relocs.h @@ -17,6 +17,7 @@ #include #include +__attribute__((__format__(printf, 1, 2))) void die(char *fmt, ...) __attribute__((noreturn)); #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) -- cgit 1.4.1 From 6d61b8e66d343d61b650f9a2ca4d8746dc6cf774 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 29 Jul 2021 23:00:22 +0900 Subject: x86/build: Remove the left-over bzlilo target Commit f279b49f13bd ("x86/boot: Modernize genimage script; hdimage+EFI support") removed the bzlilo target from arch/x86/boot/Makefile. Remove the left-over from arch/x86/Makefile. Signed-off-by: Masahiro Yamada Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/20210729140023.442101-1-masahiroy@kernel.org --- arch/x86/Makefile | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 88fb2bca6a3e..1a7c10ee9a37 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -257,8 +257,8 @@ endif $(BOOT_TARGETS): vmlinux $(Q)$(MAKE) $(build)=$(boot) $@ -PHONY += install bzlilo -install bzlilo: +PHONY += install +install: $(Q)$(MAKE) $(build)=$(boot) $@ PHONY += vdso_install -- cgit 1.4.1 From 081551266d2fbf6ce69a30c13a355ee476b2e745 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 29 Jul 2021 23:00:23 +0900 Subject: x86/build: Move the install rule to arch/x86/Makefile Currently, the install target in arch/x86/Makefile descends into arch/x86/boot/Makefile to invoke the shell script, but there is no good reason to do so. arch/x86/Makefile can run the shell script directly. Signed-off-by: Masahiro Yamada Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/20210729140023.442101-2-masahiroy@kernel.org --- arch/x86/Makefile | 3 ++- arch/x86/boot/Makefile | 7 +------ 2 files changed, 3 insertions(+), 7 deletions(-) diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 1a7c10ee9a37..d82d01490dd3 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -259,7 +259,8 @@ $(BOOT_TARGETS): vmlinux PHONY += install install: - $(Q)$(MAKE) $(build)=$(boot) $@ + $(CONFIG_SHELL) $(srctree)/$(boot)/install.sh $(KERNELRELEASE) \ + $(KBUILD_IMAGE) System.map "$(INSTALL_PATH)" PHONY += vdso_install vdso_install: diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile index dfbc26a8e924..b5aecb524a8a 100644 --- a/arch/x86/boot/Makefile +++ b/arch/x86/boot/Makefile @@ -133,7 +133,7 @@ quiet_cmd_genimage = GENIMAGE $3 cmd_genimage = $(BASH) $(srctree)/$(src)/genimage.sh $2 $3 $(obj)/bzImage \ $(obj)/mtools.conf '$(FDARGS)' $(FDINITRD) -PHONY += bzdisk fdimage fdimage144 fdimage288 hdimage isoimage install +PHONY += bzdisk fdimage fdimage144 fdimage288 hdimage isoimage # This requires write access to /dev/fd0 # All images require syslinux to be installed; hdimage also requires @@ -156,8 +156,3 @@ hdimage: $(imgdeps) isoimage: $(imgdeps) $(call cmd,genimage,isoimage,$(obj)/image.iso) @$(kecho) 'Kernel: $(obj)/image.iso is ready' - -install: - $(CONFIG_SHELL) $(srctree)/$(src)/install.sh \ - $(KERNELRELEASE) $(obj)/bzImage \ - System.map "$(INSTALL_PATH)" -- cgit 1.4.1