diff options
Diffstat (limited to 'arch/x86/Makefile')
| -rw-r--r-- | arch/x86/Makefile | 94 |
1 files changed, 62 insertions, 32 deletions
diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 662d9d4033e6..594723005d95 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -24,11 +24,15 @@ RETPOLINE_CFLAGS += $(call cc-option,-mindirect-branch-cs-prefix) ifdef CONFIG_MITIGATION_RETHUNK RETHUNK_CFLAGS := -mfunction-return=thunk-extern +RETHUNK_RUSTFLAGS := -Zfunction-return=thunk-extern RETPOLINE_CFLAGS += $(RETHUNK_CFLAGS) +RETPOLINE_RUSTFLAGS += $(RETHUNK_RUSTFLAGS) endif export RETHUNK_CFLAGS +export RETHUNK_RUSTFLAGS export RETPOLINE_CFLAGS +export RETPOLINE_RUSTFLAGS export RETPOLINE_VDSO_CFLAGS # For gcc stack alignment is specified with -mpreferred-stack-boundary, @@ -74,6 +78,26 @@ KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow -mno-avx KBUILD_RUSTFLAGS += --target=$(objtree)/scripts/target.json KBUILD_RUSTFLAGS += -Ctarget-feature=-sse,-sse2,-sse3,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 +# +# CFLAGS for compiling floating point code inside the kernel. +# +CC_FLAGS_FPU := -msse -msse2 +ifdef CONFIG_CC_IS_GCC +# Stack alignment mismatch, proceed with caution. +# GCC < 7.1 cannot compile code using `double` and -mpreferred-stack-boundary=3 +# (8B stack alignment). +# See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383 +# +# The "-msse" in the first argument is there so that the +# -mpreferred-stack-boundary=3 build error: +# +# -mpreferred-stack-boundary=3 is not between 4 and 12 +# +# can be triggered. Otherwise gcc doesn't complain. +CC_FLAGS_FPU += -mhard-float +CC_FLAGS_FPU += $(call cc-option,-msse -mpreferred-stack-boundary=3,-mpreferred-stack-boundary=4) +endif + ifeq ($(CONFIG_X86_KERNEL_IBT),y) # # Kernel IBT has S_CET.NOTRACK_EN=0, as such the compilers must not generate @@ -113,16 +137,12 @@ ifeq ($(CONFIG_X86_32),y) include $(srctree)/arch/x86/Makefile_32.cpu KBUILD_CFLAGS += $(cflags-y) - # temporary until string.h is fixed + ifneq ($(call clang-min-version, 160000),y) + # https://github.com/llvm/llvm-project/issues/53645 KBUILD_CFLAGS += -ffreestanding - - ifeq ($(CONFIG_STACKPROTECTOR),y) - ifeq ($(CONFIG_SMP),y) - KBUILD_CFLAGS += -mstack-protector-guard-reg=fs -mstack-protector-guard-symbol=__stack_chk_guard - else - KBUILD_CFLAGS += -mstack-protector-guard=global - endif endif + + percpu_seg := fs else BITS := 64 UTS_MACHINE := x86_64 @@ -153,25 +173,24 @@ else # 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) += -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 += $(cflags-y) - - rustflags-$(CONFIG_MK8) += -Ctarget-cpu=k8 - rustflags-$(CONFIG_MPSC) += -Ctarget-cpu=nocona - rustflags-$(CONFIG_MCORE2) += -Ctarget-cpu=core2 - rustflags-$(CONFIG_MATOM) += -Ctarget-cpu=atom - rustflags-$(CONFIG_GENERIC_CPU) += -Ztune-cpu=generic - KBUILD_RUSTFLAGS += $(rustflags-y) + KBUILD_CFLAGS += -march=x86-64 -mtune=generic + KBUILD_RUSTFLAGS += -Ctarget-cpu=x86-64 -Ztune-cpu=generic KBUILD_CFLAGS += -mno-red-zone KBUILD_CFLAGS += -mcmodel=kernel KBUILD_RUSTFLAGS += -Cno-redzone=y KBUILD_RUSTFLAGS += -Ccode-model=kernel + + percpu_seg := gs +endif + +ifeq ($(CONFIG_STACKPROTECTOR),y) + ifeq ($(CONFIG_SMP),y) + KBUILD_CFLAGS += -mstack-protector-guard-reg=$(percpu_seg) + KBUILD_CFLAGS += -mstack-protector-guard-symbol=__ref_stack_chk_guard + else + KBUILD_CFLAGS += -mstack-protector-guard=global + endif endif # @@ -198,9 +217,10 @@ KBUILD_CFLAGS += -fno-asynchronous-unwind-tables # Avoid indirect branches in kernel to deal with Spectre ifdef CONFIG_MITIGATION_RETPOLINE KBUILD_CFLAGS += $(RETPOLINE_CFLAGS) + KBUILD_RUSTFLAGS += $(RETPOLINE_RUSTFLAGS) # Additionally, avoid generating expensive indirect jumps which # are subject to retpolines for small number of switch cases. - # clang turns off jump table generation by default when under + # LLVM turns off jump table generation by default when under # retpoline builds, however, gcc does not for x86. This has # only been fixed starting from gcc stable version 8.4.0 and # onwards, but not for older ones. See gcc bug #86952. @@ -217,16 +237,14 @@ ifdef CONFIG_CALL_PADDING PADDING_CFLAGS := -fpatchable-function-entry=$(CONFIG_FUNCTION_PADDING_BYTES),$(CONFIG_FUNCTION_PADDING_BYTES) KBUILD_CFLAGS += $(PADDING_CFLAGS) export PADDING_CFLAGS + +PADDING_RUSTFLAGS := -Zpatchable-function-entry=$(CONFIG_FUNCTION_PADDING_BYTES),$(CONFIG_FUNCTION_PADDING_BYTES) +KBUILD_RUSTFLAGS += $(PADDING_RUSTFLAGS) +export PADDING_RUSTFLAGS endif KBUILD_LDFLAGS += -m elf_$(UTS_MACHINE) -ifdef CONFIG_X86_NEED_RELOCS -LDFLAGS_vmlinux := --emit-relocs --discard-none -else -LDFLAGS_vmlinux := -endif - # # The 64-bit kernel must be aligned to 2MB. Pass -z max-page-size=0x200000 to # the linker to force 2MB page size regardless of the default page size used @@ -247,12 +265,24 @@ archheaders: $(Q)$(MAKE) $(build)=arch/x86/entry/syscalls all ### +# <asm/cpufeaturemasks.h> header generation + +cpufeaturemasks.hdr := arch/x86/include/generated/asm/cpufeaturemasks.h +cpufeaturemasks.awk := $(srctree)/arch/x86/tools/cpufeaturemasks.awk +cpufeatures_hdr := $(srctree)/arch/x86/include/asm/cpufeatures.h +targets += $(cpufeaturemasks.hdr) + filechk_gen_featuremasks = $(AWK) -f $(cpufeaturemasks.awk) $(cpufeatures_hdr) $(KCONFIG_CONFIG) + +$(cpufeaturemasks.hdr): $(cpufeaturemasks.awk) $(cpufeatures_hdr) $(KCONFIG_CONFIG) FORCE + $(shell mkdir -p $(dir $@)) + $(call filechk,gen_featuremasks) +archprepare: $(cpufeaturemasks.hdr) + +### # Kernel objects libs-y += arch/x86/lib/ -core-y += arch/x86/virt/ - # drivers-y are linked after core-y drivers-$(CONFIG_MATH_EMULATION) += arch/x86/math-emu/ drivers-$(CONFIG_PCI) += arch/x86/pci/ @@ -260,7 +290,7 @@ drivers-$(CONFIG_PCI) += arch/x86/pci/ # suspend and hibernation support drivers-$(CONFIG_PM) += arch/x86/power/ -drivers-$(CONFIG_FB_CORE) += arch/x86/video/ +drivers-$(CONFIG_VIDEO) += arch/x86/video/ #### # boot loader support. Several targets are kept for legacy purposes |