[mirror_ubuntu-bionic-kernel.git] / arch / x86 / Makefile

# SPDX-License-Identifier: GPL-2.0
# Unified Makefile for i386 and x86_64

# select defconfig based on actual architecture
ifeq ($(ARCH),x86)
  ifeq ($(shell uname -m),x86_64)
        KBUILD_DEFCONFIG := x86_64_defconfig
  else
        KBUILD_DEFCONFIG := i386_defconfig
  endif
else
        KBUILD_DEFCONFIG := $(ARCH)_defconfig
endif

# For gcc stack alignment is specified with -mpreferred-stack-boundary,
# clang has the option -mstack-alignment for that purpose.
ifneq ($(call cc-option, -mpreferred-stack-boundary=4),)
      cc_stack_align4 := -mpreferred-stack-boundary=2
      cc_stack_align8 := -mpreferred-stack-boundary=3
else ifneq ($(call cc-option, -mstack-alignment=16),)
      cc_stack_align4 := -mstack-alignment=4
      cc_stack_align8 := -mstack-alignment=8
endif

# How to compile the 16-bit code.  Note we always compile for -march=i386;
# that way we can complain to the user if the CPU is insufficient.
#
# The -m16 option is supported by GCC >= 4.9 and clang >= 3.5. For
# older versions of GCC, include an *assembly* header to make sure that
# gcc doesn't play any games behind our back.
CODE16GCC_CFLAGS := -m32 -Wa,$(srctree)/arch/x86/boot/code16gcc.h
M16_CFLAGS	 := $(call cc-option, -m16, $(CODE16GCC_CFLAGS))

REALMODE_CFLAGS	:= $(M16_CFLAGS) -g -Os -D__KERNEL__ \
		   -DDISABLE_BRANCH_PROFILING \
		   -Wall -Wstrict-prototypes -march=i386 -mregparm=3 \
		   -fno-strict-aliasing -fomit-frame-pointer -fno-pic \
		   -mno-mmx -mno-sse

REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -ffreestanding)
REALMODE_CFLAGS += $(call __cc-option, $(CC), $(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))
export REALMODE_CFLAGS

# BITS is used as extension for files which are available in a 32 bit
# and a 64 bit version to simplify shared Makefiles.
# e.g.: obj-y += foo_$(BITS).o
export BITS

ifdef CONFIG_X86_NEED_RELOCS
        LDFLAGS_vmlinux := --emit-relocs --discard-none
endif

#
# Prevent GCC from generating any FP code by mistake.
#
# This must happen before we try the -mpreferred-stack-boundary, see:
#
#    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,)

ifeq ($(CONFIG_X86_32),y)
        BITS := 32
        UTS_MACHINE := i386
        CHECKFLAGS += -D__i386__

        biarch := $(call cc-option,-m32)
        KBUILD_AFLAGS += $(biarch)
        KBUILD_CFLAGS += $(biarch)

        KBUILD_CFLAGS += -msoft-float -mregparm=3 -freg-struct-return

        # Never want PIC in a 32-bit kernel, prevent breakage with GCC built
        # with nonstandard options
        KBUILD_CFLAGS += -fno-pic

        # 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))

        # Disable unit-at-a-time mode on pre-gcc-4.0 compilers, it makes gcc use
        # a lot more stack due to the lack of sharing of stacklots:
        KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0400, \
				$(call cc-option,-fno-unit-at-a-time))

        # CPU-specific tuning. Anything which can be shared with UML should go here.
        include arch/x86/Makefile_32.cpu
        KBUILD_CFLAGS += $(cflags-y)

        # temporary until string.h is fixed
        KBUILD_CFLAGS += -ffreestanding
else
        BITS := 64
        UTS_MACHINE := x86_64
        CHECKFLAGS += -D__x86_64__ -m64

        biarch := -m64
        KBUILD_AFLAGS += -m64
        KBUILD_CFLAGS += -m64

        # Align jump targets to 1 byte, not the default 16 bytes:
        KBUILD_CFLAGS += $(call cc-option,-falign-jumps=1)

        # Pack loops tightly as well:
        KBUILD_CFLAGS += $(call cc-option,-falign-loops=1)

        # Don't autogenerate traditional x87 instructions
        KBUILD_CFLAGS += $(call cc-option,-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.
        # However the standard kernel entry on x86-64 leaves the stack on an
        # 8-byte boundary. If the compiler isn't informed about the actual
        # alignment it will generate extra alignment instructions for the
        # 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))

	# 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)
        KBUILD_CFLAGS += $(cflags-y)

        KBUILD_CFLAGS += -mno-red-zone
        KBUILD_CFLAGS += -mcmodel=kernel

        # -funit-at-a-time shrinks the kernel .text considerably
        # unfortunately it makes reading oopses harder.
        KBUILD_CFLAGS += $(call cc-option,-funit-at-a-time)
endif

ifdef CONFIG_X86_X32
	x32_ld_ok := $(call try-run,\
			/bin/echo -e '1: .quad 1b' | \
			$(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" - && \
			$(OBJCOPY) -O elf32-x86-64 "$$TMP" "$$TMPO" && \
			$(LD) -m elf32_x86_64 "$$TMPO" -o "$$TMP",y,n)
        ifeq ($(x32_ld_ok),y)
                CONFIG_X86_X32_ABI := y
                KBUILD_AFLAGS += -DCONFIG_X86_X32_ABI
                KBUILD_CFLAGS += -DCONFIG_X86_X32_ABI
        else
                $(warning CONFIG_X86_X32 enabled but no binutils support)
        endif
endif
export CONFIG_X86_X32_ABI

#
# If the function graph tracer is used with mcount instead of fentry,
# '-maccumulate-outgoing-args' is needed to prevent a GCC bug
# (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=42109)
#
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

#
# Jump labels need '-maccumulate-outgoing-args' for gcc < 4.5.2 to prevent a
# GCC bug (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=46226).  There's no way
# to test for this bug at compile-time because the test case needs to execute,
# which is a no-go for cross compilers.  So check the GCC version instead.
#
ifdef CONFIG_JUMP_LABEL
  ifneq ($(ACCUMULATE_OUTGOING_ARGS), 1)
	ACCUMULATE_OUTGOING_ARGS = $(call cc-if-fullversion, -lt, 040502, 1)
  endif
endif

ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1)
	# This compiler flag is not supported by Clang:
	KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args,)
endif

# Stackpointer is addressed different for 32 bit and 64 bit x86
sp-$(CONFIG_X86_32) := esp
sp-$(CONFIG_X86_64) := rsp

# do binutils support CFI?
cfi := $(call as-instr,.cfi_startproc\n.cfi_rel_offset $(sp-y)$(comma)0\n.cfi_endproc,-DCONFIG_AS_CFI=1)
# is .cfi_signal_frame supported too?
cfi-sigframe := $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1)
cfi-sections := $(call as-instr,.cfi_sections .debug_frame,-DCONFIG_AS_CFI_SECTIONS=1)

# does binutils support specific instructions?
asinstr := $(call as-instr,fxsaveq (%rax),-DCONFIG_AS_FXSAVEQ=1)
asinstr += $(call as-instr,pshufb %xmm0$(comma)%xmm0,-DCONFIG_AS_SSSE3=1)
asinstr += $(call as-instr,crc32l %eax$(comma)%eax,-DCONFIG_AS_CRC32=1)
avx_instr := $(call as-instr,vxorps %ymm0$(comma)%ymm1$(comma)%ymm2,-DCONFIG_AS_AVX=1)
avx2_instr :=$(call as-instr,vpbroadcastb %xmm0$(comma)%ymm1,-DCONFIG_AS_AVX2=1)
avx512_instr :=$(call as-instr,vpmovm2b %k1$(comma)%zmm5,-DCONFIG_AS_AVX512=1)
sha1_ni_instr :=$(call as-instr,sha1msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA1_NI=1)
sha256_ni_instr :=$(call as-instr,sha256msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA256_NI=1)

KBUILD_AFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr)
KBUILD_CFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr)

LDFLAGS := -m elf_$(UTS_MACHINE)

#
# 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
# by the linker.
#
ifdef CONFIG_X86_64
LDFLAGS += $(call ld-option, -z max-page-size=0x200000)
endif

# Speed up the build
KBUILD_CFLAGS += -pipe
# Workaround for a gcc prelease that unfortunately was shipped in a suse release
KBUILD_CFLAGS += -Wno-sign-compare
#
KBUILD_CFLAGS += -fno-asynchronous-unwind-tables

# Avoid indirect branches in kernel to deal with Spectre
ifdef CONFIG_RETPOLINE
  KBUILD_CFLAGS += $(RETPOLINE_CFLAGS)
  # Additionally, avoid generating expensive indirect jumps which
  # are subject to retpolines for small number of switch cases.
  # clang turns off jump table generation by default when under
  # retpoline builds, however, gcc does not for x86. This has
  # only been fixed starting from gcc stable version 8.4.0 and
  # onwards, but not for older ones. See gcc bug #86952.
  ifneq ($(cc-name), clang)
    KBUILD_CFLAGS += $(call cc-option,-fno-jump-tables)
  endif
endif

archscripts: scripts_basic
	$(Q)$(MAKE) $(build)=arch/x86/tools relocs

###
# Syscall table generation

archheaders:
	$(Q)$(MAKE) $(build)=arch/x86/entry/syscalls all

archprepare:
ifeq ($(CONFIG_KEXEC_FILE),y)
	$(Q)$(MAKE) $(build)=arch/x86/purgatory arch/x86/purgatory/kexec-purgatory.c
endif
ifdef CONFIG_RETPOLINE
ifeq ($(RETPOLINE_CFLAGS),)
	@echo "You are building kernel with non-retpoline compiler." >&2
	@echo "Please update your compiler." >&2
	@false
endif
endif

###
# Kernel objects

head-y := arch/x86/kernel/head_$(BITS).o
head-y += arch/x86/kernel/head$(BITS).o
head-y += arch/x86/kernel/ebda.o
head-y += arch/x86/kernel/platform-quirks.o

libs-y  += arch/x86/lib/

# See arch/x86/Kbuild for content of core part of the kernel
core-y += arch/x86/

# drivers-y are linked after core-y
drivers-$(CONFIG_MATH_EMULATION) += arch/x86/math-emu/
drivers-$(CONFIG_PCI)            += arch/x86/pci/

# must be linked after kernel/
drivers-$(CONFIG_OPROFILE) += arch/x86/oprofile/

# suspend and hibernation support
drivers-$(CONFIG_PM) += arch/x86/power/

drivers-$(CONFIG_FB) += arch/x86/video/

####
# boot loader support. Several targets are kept for legacy purposes

boot := arch/x86/boot

BOOT_TARGETS = bzlilo bzdisk fdimage fdimage144 fdimage288 isoimage

PHONY += bzImage $(BOOT_TARGETS)

# Default kernel to build
all: bzImage

# KBUILD_IMAGE specify target image being built
KBUILD_IMAGE := $(boot)/bzImage

bzImage: vmlinux
ifeq ($(CONFIG_X86_DECODER_SELFTEST),y)
	$(Q)$(MAKE) $(build)=arch/x86/tools posttest
endif
	$(Q)$(MAKE) $(build)=$(boot) $(KBUILD_IMAGE)
	$(Q)mkdir -p $(objtree)/arch/$(UTS_MACHINE)/boot
	$(Q)ln -fsn ../../x86/boot/bzImage $(objtree)/arch/$(UTS_MACHINE)/boot/$@

$(BOOT_TARGETS): vmlinux
	$(Q)$(MAKE) $(build)=$(boot) $@

PHONY += install
install:
	$(Q)$(MAKE) $(build)=$(boot) $@

PHONY += vdso_install
vdso_install:
	$(Q)$(MAKE) $(build)=arch/x86/entry/vdso $@

archclean:
	$(Q)rm -rf $(objtree)/arch/i386
	$(Q)rm -rf $(objtree)/arch/x86_64
	$(Q)$(MAKE) $(clean)=$(boot)
	$(Q)$(MAKE) $(clean)=arch/x86/tools
	$(Q)$(MAKE) $(clean)=arch/x86/purgatory

define archhelp
  echo  '* bzImage      - Compressed kernel image (arch/x86/boot/bzImage)'
  echo  '  install      - Install kernel using'
  echo  '                  (your) ~/bin/$(INSTALLKERNEL) or'
  echo  '                  (distribution) /sbin/$(INSTALLKERNEL) or'
  echo  '                  install to $$(INSTALL_PATH) and run lilo'
  echo  '  fdimage      - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)'
  echo  '  fdimage144   - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)'
  echo  '  fdimage288   - Create 2.8MB boot floppy image (arch/x86/boot/fdimage)'
  echo  '  isoimage     - Create a boot CD-ROM image (arch/x86/boot/image.iso)'
  echo  '                  bzdisk/fdimage*/isoimage also accept:'
  echo  '                  FDARGS="..."  arguments for the booted kernel'
  echo  '                  FDINITRD=file initrd for the booted kernel'
endef
Commit	Line	Data
	1	# SPDX-License-Identifier: GPL-2.0
	2	# Unified Makefile for i386 and x86_64
	3
	4	# select defconfig based on actual architecture
	5	ifeq ($(ARCH),x86)
	6	ifeq ($(shell uname -m),x86_64)
	7	KBUILD_DEFCONFIG := x86_64_defconfig
	8	else
	9	KBUILD_DEFCONFIG := i386_defconfig
	10	endif
	11	else
	12	KBUILD_DEFCONFIG := $(ARCH)_defconfig
	13	endif
	14
	15	# For gcc stack alignment is specified with -mpreferred-stack-boundary,
	16	# clang has the option -mstack-alignment for that purpose.
	17	ifneq ($(call cc-option, -mpreferred-stack-boundary=4),)
	18	cc_stack_align4 := -mpreferred-stack-boundary=2
	19	cc_stack_align8 := -mpreferred-stack-boundary=3
	20	else ifneq ($(call cc-option, -mstack-alignment=16),)
	21	cc_stack_align4 := -mstack-alignment=4
	22	cc_stack_align8 := -mstack-alignment=8
	23	endif
	24
	25	# How to compile the 16-bit code. Note we always compile for -march=i386;
	26	# that way we can complain to the user if the CPU is insufficient.
	27	#
	28	# The -m16 option is supported by GCC >= 4.9 and clang >= 3.5. For
	29	# older versions of GCC, include an assembly header to make sure that
	30	# gcc doesn't play any games behind our back.
	31	CODE16GCC_CFLAGS := -m32 -Wa,$(srctree)/arch/x86/boot/code16gcc.h
	32	M16_CFLAGS := $(call cc-option, -m16, $(CODE16GCC_CFLAGS))
	33
	34	REALMODE_CFLAGS := $(M16_CFLAGS) -g -Os -D__KERNEL__ \
	35	-DDISABLE_BRANCH_PROFILING \
	36	-Wall -Wstrict-prototypes -march=i386 -mregparm=3 \
	37	-fno-strict-aliasing -fomit-frame-pointer -fno-pic \
	38	-mno-mmx -mno-sse
	39
	40	REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -ffreestanding)
	41	REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -fno-stack-protector)
	42	REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -Wno-address-of-packed-member)
	43	REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), $(cc_stack_align4))
	44	export REALMODE_CFLAGS
	45
	46	# BITS is used as extension for files which are available in a 32 bit
	47	# and a 64 bit version to simplify shared Makefiles.
	48	# e.g.: obj-y += foo_$(BITS).o
	49	export BITS
	50
	51	ifdef CONFIG_X86_NEED_RELOCS
	52	LDFLAGS_vmlinux := --emit-relocs --discard-none
	53	endif
	54
	55	#
	56	# Prevent GCC from generating any FP code by mistake.
	57	#
	58	# This must happen before we try the -mpreferred-stack-boundary, see:
	59	#
	60	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383
	61	#
	62	KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow
	63	KBUILD_CFLAGS += $(call cc-option,-mno-avx,)
	64
	65	ifeq ($(CONFIG_X86_32),y)
	66	BITS := 32
	67	UTS_MACHINE := i386
	68	CHECKFLAGS += -D__i386__
	69
	70	biarch := $(call cc-option,-m32)
	71	KBUILD_AFLAGS += $(biarch)
	72	KBUILD_CFLAGS += $(biarch)
	73
	74	KBUILD_CFLAGS += -msoft-float -mregparm=3 -freg-struct-return
	75
	76	# Never want PIC in a 32-bit kernel, prevent breakage with GCC built
	77	# with nonstandard options
	78	KBUILD_CFLAGS += -fno-pic
	79
	80	# Align the stack to the register width instead of using the default
	81	# alignment of 16 bytes. This reduces stack usage and the number of
	82	# alignment instructions.
	83	KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align4))
	84
	85	# Disable unit-at-a-time mode on pre-gcc-4.0 compilers, it makes gcc use
	86	# a lot more stack due to the lack of sharing of stacklots:
	87	KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0400, \
	88	$(call cc-option,-fno-unit-at-a-time))
	89
	90	# CPU-specific tuning. Anything which can be shared with UML should go here.
	91	include arch/x86/Makefile_32.cpu
	92	KBUILD_CFLAGS += $(cflags-y)
	93
	94	# temporary until string.h is fixed
	95	KBUILD_CFLAGS += -ffreestanding
	96	else
	97	BITS := 64
	98	UTS_MACHINE := x86_64
	99	CHECKFLAGS += -D__x86_64__ -m64
	100
	101	biarch := -m64
	102	KBUILD_AFLAGS += -m64
	103	KBUILD_CFLAGS += -m64
	104
	105	# Align jump targets to 1 byte, not the default 16 bytes:
	106	KBUILD_CFLAGS += $(call cc-option,-falign-jumps=1)
	107
	108	# Pack loops tightly as well:
	109	KBUILD_CFLAGS += $(call cc-option,-falign-loops=1)
	110
	111	# Don't autogenerate traditional x87 instructions
	112	KBUILD_CFLAGS += $(call cc-option,-mno-80387)
	113	KBUILD_CFLAGS += $(call cc-option,-mno-fp-ret-in-387)
	114
	115	# By default gcc and clang use a stack alignment of 16 bytes for x86.
	116	# However the standard kernel entry on x86-64 leaves the stack on an
	117	# 8-byte boundary. If the compiler isn't informed about the actual
	118	# alignment it will generate extra alignment instructions for the
	119	# default alignment which keep the stack misaligned.
	120	# Furthermore an alignment to the register width reduces stack usage
	121	# and the number of alignment instructions.
	122	KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align8))
	123
	124	# Use -mskip-rax-setup if supported.
	125	KBUILD_CFLAGS += $(call cc-option,-mskip-rax-setup)
	126
	127	# FIXME - should be integrated in Makefile.cpu (Makefile_32.cpu)
	128	cflags-$(CONFIG_MK8) += $(call cc-option,-march=k8)
	129	cflags-$(CONFIG_MPSC) += $(call cc-option,-march=nocona)
	130
	131	cflags-$(CONFIG_MCORE2) += \
	132	$(call cc-option,-march=core2,$(call cc-option,-mtune=generic))
	133	cflags-$(CONFIG_MATOM) += $(call cc-option,-march=atom) \
	134	$(call cc-option,-mtune=atom,$(call cc-option,-mtune=generic))
	135	cflags-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=generic)
	136	KBUILD_CFLAGS += $(cflags-y)
	137
	138	KBUILD_CFLAGS += -mno-red-zone
	139	KBUILD_CFLAGS += -mcmodel=kernel
	140
	141	# -funit-at-a-time shrinks the kernel .text considerably
	142	# unfortunately it makes reading oopses harder.
	143	KBUILD_CFLAGS += $(call cc-option,-funit-at-a-time)
	144	endif
	145
	146	ifdef CONFIG_X86_X32
	147	x32_ld_ok := $(call try-run,\
	148	/bin/echo -e '1: .quad 1b' \| \
	149	$(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" - && \
	150	$(OBJCOPY) -O elf32-x86-64 "$$TMP" "$$TMPO" && \
	151	$(LD) -m elf32_x86_64 "$$TMPO" -o "$$TMP",y,n)
	152	ifeq ($(x32_ld_ok),y)
	153	CONFIG_X86_X32_ABI := y
	154	KBUILD_AFLAGS += -DCONFIG_X86_X32_ABI
	155	KBUILD_CFLAGS += -DCONFIG_X86_X32_ABI
	156	else
	157	$(warning CONFIG_X86_X32 enabled but no binutils support)
	158	endif
	159	endif
	160	export CONFIG_X86_X32_ABI
	161
	162	#
	163	# If the function graph tracer is used with mcount instead of fentry,
	164	# '-maccumulate-outgoing-args' is needed to prevent a GCC bug
	165	# (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=42109)
	166	#
	167	ifdef CONFIG_FUNCTION_GRAPH_TRACER
	168	ifndef CONFIG_HAVE_FENTRY
	169	ACCUMULATE_OUTGOING_ARGS := 1
	170	else
	171	ifeq ($(call cc-option-yn, -mfentry), n)
	172	ACCUMULATE_OUTGOING_ARGS := 1
	173
	174	# GCC ignores '-maccumulate-outgoing-args' when used with '-Os'.
	175	# If '-Os' is enabled, disable it and print a warning.
	176	ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
	177	undefine CONFIG_CC_OPTIMIZE_FOR_SIZE
	178	$(warning Disabling CONFIG_CC_OPTIMIZE_FOR_SIZE. Your compiler does not have -mfentry so you cannot optimize for size with CONFIG_FUNCTION_GRAPH_TRACER.)
	179	endif
	180
	181	endif
	182	endif
	183	endif
	184
	185	#
	186	# Jump labels need '-maccumulate-outgoing-args' for gcc < 4.5.2 to prevent a
	187	# GCC bug (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=46226). There's no way
	188	# to test for this bug at compile-time because the test case needs to execute,
	189	# which is a no-go for cross compilers. So check the GCC version instead.
	190	#
	191	ifdef CONFIG_JUMP_LABEL
	192	ifneq ($(ACCUMULATE_OUTGOING_ARGS), 1)
	193	ACCUMULATE_OUTGOING_ARGS = $(call cc-if-fullversion, -lt, 040502, 1)
	194	endif
	195	endif
	196
	197	ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1)
	198	# This compiler flag is not supported by Clang:
	199	KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args,)
	200	endif
	201
	202	# Stackpointer is addressed different for 32 bit and 64 bit x86
	203	sp-$(CONFIG_X86_32) := esp
	204	sp-$(CONFIG_X86_64) := rsp
	205
	206	# do binutils support CFI?
	207	cfi := $(call as-instr,.cfi_startproc\n.cfi_rel_offset $(sp-y)$(comma)0\n.cfi_endproc,-DCONFIG_AS_CFI=1)
	208	# is .cfi_signal_frame supported too?
	209	cfi-sigframe := $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1)
	210	cfi-sections := $(call as-instr,.cfi_sections .debug_frame,-DCONFIG_AS_CFI_SECTIONS=1)
	211
	212	# does binutils support specific instructions?
	213	asinstr := $(call as-instr,fxsaveq (%rax),-DCONFIG_AS_FXSAVEQ=1)
	214	asinstr += $(call as-instr,pshufb %xmm0$(comma)%xmm0,-DCONFIG_AS_SSSE3=1)
	215	asinstr += $(call as-instr,crc32l %eax$(comma)%eax,-DCONFIG_AS_CRC32=1)
	216	avx_instr := $(call as-instr,vxorps %ymm0$(comma)%ymm1$(comma)%ymm2,-DCONFIG_AS_AVX=1)
	217	avx2_instr :=$(call as-instr,vpbroadcastb %xmm0$(comma)%ymm1,-DCONFIG_AS_AVX2=1)
	218	avx512_instr :=$(call as-instr,vpmovm2b %k1$(comma)%zmm5,-DCONFIG_AS_AVX512=1)
	219	sha1_ni_instr :=$(call as-instr,sha1msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA1_NI=1)
	220	sha256_ni_instr :=$(call as-instr,sha256msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA256_NI=1)
	221
	222	KBUILD_AFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr)
	223	KBUILD_CFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr)
	224
	225	LDFLAGS := -m elf_$(UTS_MACHINE)
	226
	227	#
	228	# The 64-bit kernel must be aligned to 2MB. Pass -z max-page-size=0x200000 to
	229	# the linker to force 2MB page size regardless of the default page size used
	230	# by the linker.
	231	#
	232	ifdef CONFIG_X86_64
	233	LDFLAGS += $(call ld-option, -z max-page-size=0x200000)
	234	endif
	235
	236	# Speed up the build
	237	KBUILD_CFLAGS += -pipe
	238	# Workaround for a gcc prelease that unfortunately was shipped in a suse release
	239	KBUILD_CFLAGS += -Wno-sign-compare
	240	#
	241	KBUILD_CFLAGS += -fno-asynchronous-unwind-tables
	242
	243	# Avoid indirect branches in kernel to deal with Spectre
	244	ifdef CONFIG_RETPOLINE
	245	KBUILD_CFLAGS += $(RETPOLINE_CFLAGS)
	246	# Additionally, avoid generating expensive indirect jumps which
	247	# are subject to retpolines for small number of switch cases.
	248	# clang turns off jump table generation by default when under
	249	# retpoline builds, however, gcc does not for x86. This has
	250	# only been fixed starting from gcc stable version 8.4.0 and
	251	# onwards, but not for older ones. See gcc bug #86952.
	252	ifneq ($(cc-name), clang)
	253	KBUILD_CFLAGS += $(call cc-option,-fno-jump-tables)
	254	endif
	255	endif
	256
	257	archscripts: scripts_basic
	258	$(Q)$(MAKE) $(build)=arch/x86/tools relocs
	259
	260	###
	261	# Syscall table generation
	262
	263	archheaders:
	264	$(Q)$(MAKE) $(build)=arch/x86/entry/syscalls all
	265
	266	archprepare:
	267	ifeq ($(CONFIG_KEXEC_FILE),y)
	268	$(Q)$(MAKE) $(build)=arch/x86/purgatory arch/x86/purgatory/kexec-purgatory.c
	269	endif
	270	ifdef CONFIG_RETPOLINE
	271	ifeq ($(RETPOLINE_CFLAGS),)
	272	@echo "You are building kernel with non-retpoline compiler." >&2
	273	@echo "Please update your compiler." >&2
	274	@false
	275	endif
	276	endif
	277
	278	###
	279	# Kernel objects
	280
	281	head-y := arch/x86/kernel/head_$(BITS).o
	282	head-y += arch/x86/kernel/head$(BITS).o
	283	head-y += arch/x86/kernel/ebda.o
	284	head-y += arch/x86/kernel/platform-quirks.o
	285
	286	libs-y += arch/x86/lib/
	287
	288	# See arch/x86/Kbuild for content of core part of the kernel
	289	core-y += arch/x86/
	290
	291	# drivers-y are linked after core-y
	292	drivers-$(CONFIG_MATH_EMULATION) += arch/x86/math-emu/
	293	drivers-$(CONFIG_PCI) += arch/x86/pci/
	294
	295	# must be linked after kernel/
	296	drivers-$(CONFIG_OPROFILE) += arch/x86/oprofile/
	297
	298	# suspend and hibernation support
	299	drivers-$(CONFIG_PM) += arch/x86/power/
	300
	301	drivers-$(CONFIG_FB) += arch/x86/video/
	302
	303	####
	304	# boot loader support. Several targets are kept for legacy purposes
	305
	306	boot := arch/x86/boot
	307
	308	BOOT_TARGETS = bzlilo bzdisk fdimage fdimage144 fdimage288 isoimage
	309
	310	PHONY += bzImage $(BOOT_TARGETS)
	311
	312	# Default kernel to build
	313	all: bzImage
	314
	315	# KBUILD_IMAGE specify target image being built
	316	KBUILD_IMAGE := $(boot)/bzImage
	317
	318	bzImage: vmlinux
	319	ifeq ($(CONFIG_X86_DECODER_SELFTEST),y)
	320	$(Q)$(MAKE) $(build)=arch/x86/tools posttest
	321	endif
	322	$(Q)$(MAKE) $(build)=$(boot) $(KBUILD_IMAGE)
	323	$(Q)mkdir -p $(objtree)/arch/$(UTS_MACHINE)/boot
	324	$(Q)ln -fsn ../../x86/boot/bzImage $(objtree)/arch/$(UTS_MACHINE)/boot/$@
	325
	326	$(BOOT_TARGETS): vmlinux
	327	$(Q)$(MAKE) $(build)=$(boot) $@
	328
	329	PHONY += install
	330	install:
	331	$(Q)$(MAKE) $(build)=$(boot) $@
	332
	333	PHONY += vdso_install
	334	vdso_install:
	335	$(Q)$(MAKE) $(build)=arch/x86/entry/vdso $@
	336
	337	archclean:
	338	$(Q)rm -rf $(objtree)/arch/i386
	339	$(Q)rm -rf $(objtree)/arch/x86_64
	340	$(Q)$(MAKE) $(clean)=$(boot)
	341	$(Q)$(MAKE) $(clean)=arch/x86/tools
	342	$(Q)$(MAKE) $(clean)=arch/x86/purgatory
	343
	344	define archhelp
	345	echo '* bzImage - Compressed kernel image (arch/x86/boot/bzImage)'
	346	echo ' install - Install kernel using'
	347	echo ' (your) ~/bin/$(INSTALLKERNEL) or'
	348	echo ' (distribution) /sbin/$(INSTALLKERNEL) or'
	349	echo ' install to $$(INSTALL_PATH) and run lilo'
	350	echo ' fdimage - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)'
	351	echo ' fdimage144 - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)'
	352	echo ' fdimage288 - Create 2.8MB boot floppy image (arch/x86/boot/fdimage)'
	353	echo ' isoimage - Create a boot CD-ROM image (arch/x86/boot/image.iso)'
	354	echo ' bzdisk/fdimage*/isoimage also accept:'
	355	echo ' FDARGS="..." arguments for the booted kernel'
	356	echo ' FDINITRD=file initrd for the booted kernel'
	357	endef