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1# SPDX-License-Identifier: GPL-2.0
2# Unified Makefile for i386 and x86_64
3
4# select defconfig based on actual architecture
5ifeq ($(ARCH),x86)
6 ifeq ($(shell uname -m | sed -e 's/i.86/i386/'),i386)
7 KBUILD_DEFCONFIG := i386_defconfig
8 else
9 KBUILD_DEFCONFIG := x86_64_defconfig
10 endif
11else
12 KBUILD_DEFCONFIG := $(ARCH)_defconfig
13endif
14
15ifdef CONFIG_CC_IS_GCC
16RETPOLINE_CFLAGS := $(call cc-option,-mindirect-branch=thunk-extern -mindirect-branch-register)
17RETPOLINE_VDSO_CFLAGS := $(call cc-option,-mindirect-branch=thunk-inline -mindirect-branch-register)
18endif
19ifdef CONFIG_CC_IS_CLANG
20RETPOLINE_CFLAGS := -mretpoline-external-thunk
21RETPOLINE_VDSO_CFLAGS := -mretpoline
22endif
23RETPOLINE_CFLAGS += $(call cc-option,-mindirect-branch-cs-prefix)
24
25ifdef CONFIG_MITIGATION_RETHUNK
26RETHUNK_CFLAGS := -mfunction-return=thunk-extern
27RETHUNK_RUSTFLAGS := -Zfunction-return=thunk-extern
28RETPOLINE_CFLAGS += $(RETHUNK_CFLAGS)
29RETPOLINE_RUSTFLAGS += $(RETHUNK_RUSTFLAGS)
30endif
31
32export RETHUNK_CFLAGS
33export RETHUNK_RUSTFLAGS
34export RETPOLINE_CFLAGS
35export RETPOLINE_RUSTFLAGS
36export RETPOLINE_VDSO_CFLAGS
37
38# For gcc stack alignment is specified with -mpreferred-stack-boundary,
39# clang has the option -mstack-alignment for that purpose.
40ifneq ($(call cc-option, -mpreferred-stack-boundary=4),)
41 cc_stack_align4 := -mpreferred-stack-boundary=2
42 cc_stack_align8 := -mpreferred-stack-boundary=3
43else ifneq ($(call cc-option, -mstack-alignment=16),)
44 cc_stack_align4 := -mstack-alignment=4
45 cc_stack_align8 := -mstack-alignment=8
46endif
47
48# How to compile the 16-bit code. Note we always compile for -march=i386;
49# that way we can complain to the user if the CPU is insufficient.
50REALMODE_CFLAGS := -std=gnu11 -m16 -g -Os -DDISABLE_BRANCH_PROFILING -D__DISABLE_EXPORTS \
51 -Wall -Wstrict-prototypes -march=i386 -mregparm=3 \
52 -fno-strict-aliasing -fomit-frame-pointer -fno-pic \
53 -mno-mmx -mno-sse $(call cc-option,-fcf-protection=none)
54
55REALMODE_CFLAGS += -ffreestanding
56REALMODE_CFLAGS += -fno-stack-protector
57REALMODE_CFLAGS += -Wno-address-of-packed-member
58REALMODE_CFLAGS += $(cc_stack_align4)
59REALMODE_CFLAGS += $(CLANG_FLAGS)
60ifdef CONFIG_CC_IS_CLANG
61REALMODE_CFLAGS += -Wno-gnu
62endif
63export REALMODE_CFLAGS
64
65# BITS is used as extension for files which are available in a 32 bit
66# and a 64 bit version to simplify shared Makefiles.
67# e.g.: obj-y += foo_$(BITS).o
68export BITS
69
70#
71# Prevent GCC from generating any FP code by mistake.
72#
73# This must happen before we try the -mpreferred-stack-boundary, see:
74#
75# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383
76#
77KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow -mno-avx
78KBUILD_RUSTFLAGS += --target=$(objtree)/scripts/target.json
79KBUILD_RUSTFLAGS += -Ctarget-feature=-sse,-sse2,-sse3,-ssse3,-sse4.1,-sse4.2,-avx,-avx2
80
81#
82# CFLAGS for compiling floating point code inside the kernel.
83#
84CC_FLAGS_FPU := -msse -msse2
85ifdef CONFIG_CC_IS_GCC
86# Stack alignment mismatch, proceed with caution.
87# GCC < 7.1 cannot compile code using `double` and -mpreferred-stack-boundary=3
88# (8B stack alignment).
89# See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383
90#
91# The "-msse" in the first argument is there so that the
92# -mpreferred-stack-boundary=3 build error:
93#
94# -mpreferred-stack-boundary=3 is not between 4 and 12
95#
96# can be triggered. Otherwise gcc doesn't complain.
97CC_FLAGS_FPU += -mhard-float
98CC_FLAGS_FPU += $(call cc-option,-msse -mpreferred-stack-boundary=3,-mpreferred-stack-boundary=4)
99endif
100
101ifeq ($(CONFIG_X86_KERNEL_IBT),y)
102#
103# Kernel IBT has S_CET.NOTRACK_EN=0, as such the compilers must not generate
104# NOTRACK prefixes. Current generation compilers unconditionally employ NOTRACK
105# for jump-tables, as such, disable jump-tables for now.
106#
107# (jump-tables are implicitly disabled by RETPOLINE)
108#
109# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104816
110#
111KBUILD_CFLAGS += $(call cc-option,-fcf-protection=branch -fno-jump-tables)
112KBUILD_RUSTFLAGS += -Zcf-protection=branch -Zno-jump-tables
113else
114KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
115endif
116
117ifeq ($(CONFIG_X86_32),y)
118 BITS := 32
119 UTS_MACHINE := i386
120 CHECKFLAGS += -D__i386__
121
122 KBUILD_AFLAGS += -m32
123 KBUILD_CFLAGS += -m32
124
125 KBUILD_CFLAGS += -msoft-float -mregparm=3 -freg-struct-return
126
127 # Never want PIC in a 32-bit kernel, prevent breakage with GCC built
128 # with nonstandard options
129 KBUILD_CFLAGS += -fno-pic
130
131 # Align the stack to the register width instead of using the default
132 # alignment of 16 bytes. This reduces stack usage and the number of
133 # alignment instructions.
134 KBUILD_CFLAGS += $(cc_stack_align4)
135
136 # CPU-specific tuning. Anything which can be shared with UML should go here.
137 include $(srctree)/arch/x86/Makefile_32.cpu
138 KBUILD_CFLAGS += $(cflags-y)
139
140 # temporary until string.h is fixed
141 KBUILD_CFLAGS += -ffreestanding
142
143 ifeq ($(CONFIG_STACKPROTECTOR),y)
144 ifeq ($(CONFIG_SMP),y)
145 KBUILD_CFLAGS += -mstack-protector-guard-reg=fs \
146 -mstack-protector-guard-symbol=__ref_stack_chk_guard
147 else
148 KBUILD_CFLAGS += -mstack-protector-guard=global
149 endif
150 endif
151else
152 BITS := 64
153 UTS_MACHINE := x86_64
154 CHECKFLAGS += -D__x86_64__
155
156 KBUILD_AFLAGS += -m64
157 KBUILD_CFLAGS += -m64
158
159 # Align jump targets to 1 byte, not the default 16 bytes:
160 KBUILD_CFLAGS += $(call cc-option,-falign-jumps=1)
161
162 # Pack loops tightly as well:
163 KBUILD_CFLAGS += $(call cc-option,-falign-loops=1)
164
165 # Don't autogenerate traditional x87 instructions
166 KBUILD_CFLAGS += -mno-80387
167 KBUILD_CFLAGS += $(call cc-option,-mno-fp-ret-in-387)
168
169 # By default gcc and clang use a stack alignment of 16 bytes for x86.
170 # However the standard kernel entry on x86-64 leaves the stack on an
171 # 8-byte boundary. If the compiler isn't informed about the actual
172 # alignment it will generate extra alignment instructions for the
173 # default alignment which keep the stack *mis*aligned.
174 # Furthermore an alignment to the register width reduces stack usage
175 # and the number of alignment instructions.
176 KBUILD_CFLAGS += $(cc_stack_align8)
177
178 # Use -mskip-rax-setup if supported.
179 KBUILD_CFLAGS += $(call cc-option,-mskip-rax-setup)
180
181 # FIXME - should be integrated in Makefile.cpu (Makefile_32.cpu)
182 cflags-$(CONFIG_MK8) += -march=k8
183 cflags-$(CONFIG_MPSC) += -march=nocona
184 cflags-$(CONFIG_MCORE2) += -march=core2
185 cflags-$(CONFIG_MATOM) += -march=atom
186 cflags-$(CONFIG_GENERIC_CPU) += -mtune=generic
187 KBUILD_CFLAGS += $(cflags-y)
188
189 rustflags-$(CONFIG_MK8) += -Ctarget-cpu=k8
190 rustflags-$(CONFIG_MPSC) += -Ctarget-cpu=nocona
191 rustflags-$(CONFIG_MCORE2) += -Ctarget-cpu=core2
192 rustflags-$(CONFIG_MATOM) += -Ctarget-cpu=atom
193 rustflags-$(CONFIG_GENERIC_CPU) += -Ztune-cpu=generic
194 KBUILD_RUSTFLAGS += $(rustflags-y)
195
196 KBUILD_CFLAGS += -mno-red-zone
197 KBUILD_CFLAGS += -mcmodel=kernel
198 KBUILD_RUSTFLAGS += -Cno-redzone=y
199 KBUILD_RUSTFLAGS += -Ccode-model=kernel
200endif
201
202#
203# If the function graph tracer is used with mcount instead of fentry,
204# '-maccumulate-outgoing-args' is needed to prevent a GCC bug
205# (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=42109)
206#
207ifdef CONFIG_FUNCTION_GRAPH_TRACER
208 ifndef CONFIG_HAVE_FENTRY
209 ACCUMULATE_OUTGOING_ARGS := 1
210 endif
211endif
212
213ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1)
214 # This compiler flag is not supported by Clang:
215 KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args,)
216endif
217
218# Workaround for a gcc prelease that unfortunately was shipped in a suse release
219KBUILD_CFLAGS += -Wno-sign-compare
220#
221KBUILD_CFLAGS += -fno-asynchronous-unwind-tables
222
223# Avoid indirect branches in kernel to deal with Spectre
224ifdef CONFIG_MITIGATION_RETPOLINE
225 KBUILD_CFLAGS += $(RETPOLINE_CFLAGS)
226 KBUILD_RUSTFLAGS += $(RETPOLINE_RUSTFLAGS)
227 # Additionally, avoid generating expensive indirect jumps which
228 # are subject to retpolines for small number of switch cases.
229 # LLVM turns off jump table generation by default when under
230 # retpoline builds, however, gcc does not for x86. This has
231 # only been fixed starting from gcc stable version 8.4.0 and
232 # onwards, but not for older ones. See gcc bug #86952.
233 ifndef CONFIG_CC_IS_CLANG
234 KBUILD_CFLAGS += -fno-jump-tables
235 endif
236endif
237
238ifdef CONFIG_MITIGATION_SLS
239 KBUILD_CFLAGS += -mharden-sls=all
240endif
241
242ifdef CONFIG_CALL_PADDING
243PADDING_CFLAGS := -fpatchable-function-entry=$(CONFIG_FUNCTION_PADDING_BYTES),$(CONFIG_FUNCTION_PADDING_BYTES)
244KBUILD_CFLAGS += $(PADDING_CFLAGS)
245export PADDING_CFLAGS
246
247PADDING_RUSTFLAGS := -Zpatchable-function-entry=$(CONFIG_FUNCTION_PADDING_BYTES),$(CONFIG_FUNCTION_PADDING_BYTES)
248KBUILD_RUSTFLAGS += $(PADDING_RUSTFLAGS)
249export PADDING_RUSTFLAGS
250endif
251
252KBUILD_LDFLAGS += -m elf_$(UTS_MACHINE)
253
254ifdef CONFIG_X86_NEED_RELOCS
255LDFLAGS_vmlinux := --emit-relocs --discard-none
256else
257LDFLAGS_vmlinux :=
258endif
259
260#
261# The 64-bit kernel must be aligned to 2MB. Pass -z max-page-size=0x200000 to
262# the linker to force 2MB page size regardless of the default page size used
263# by the linker.
264#
265ifdef CONFIG_X86_64
266LDFLAGS_vmlinux += -z max-page-size=0x200000
267endif
268
269
270archscripts: scripts_basic
271 $(Q)$(MAKE) $(build)=arch/x86/tools relocs
272
273###
274# Syscall table generation
275
276archheaders:
277 $(Q)$(MAKE) $(build)=arch/x86/entry/syscalls all
278
279###
280# Kernel objects
281
282libs-y += arch/x86/lib
283
284# drivers-y are linked after core-y
285drivers-$(CONFIG_MATH_EMULATION) += arch/x86/math-emu/
286drivers-$(CONFIG_PCI) += arch/x86/pci/
287
288# suspend and hibernation support
289drivers-$(CONFIG_PM) += arch/x86/power/
290
291drivers-$(CONFIG_VIDEO) += arch/x86/video/
292
293####
294# boot loader support. Several targets are kept for legacy purposes
295
296boot := arch/x86/boot
297
298BOOT_TARGETS = bzdisk fdimage fdimage144 fdimage288 hdimage isoimage
299
300PHONY += bzImage $(BOOT_TARGETS)
301
302# Default kernel to build
303all: bzImage
304
305# KBUILD_IMAGE specify target image being built
306KBUILD_IMAGE := $(boot)/bzImage
307
308bzImage: vmlinux
309ifeq ($(CONFIG_X86_DECODER_SELFTEST),y)
310 $(Q)$(MAKE) $(build)=arch/x86/tools posttest
311endif
312 $(Q)$(MAKE) $(build)=$(boot) $(KBUILD_IMAGE)
313 $(Q)mkdir -p $(objtree)/arch/$(UTS_MACHINE)/boot
314 $(Q)ln -fsn ../../x86/boot/bzImage $(objtree)/arch/$(UTS_MACHINE)/boot/$@
315
316$(BOOT_TARGETS): vmlinux
317 $(Q)$(MAKE) $(build)=$(boot) $@
318
319PHONY += install
320install:
321 $(call cmd,install)
322
323vdso-install-$(CONFIG_X86_64) += arch/x86/entry/vdso/vdso64.so.dbg
324vdso-install-$(CONFIG_X86_X32_ABI) += arch/x86/entry/vdso/vdsox32.so.dbg
325vdso-install-$(CONFIG_COMPAT_32) += arch/x86/entry/vdso/vdso32.so.dbg
326
327archprepare: checkbin
328checkbin:
329ifdef CONFIG_MITIGATION_RETPOLINE
330ifeq ($(RETPOLINE_CFLAGS),)
331 @echo "You are building kernel with non-retpoline compiler." >&2
332 @echo "Please update your compiler." >&2
333 @false
334endif
335endif
336
337ifdef CONFIG_UNWINDER_ORC
338orc_hash_h := arch/$(SRCARCH)/include/generated/asm/orc_hash.h
339orc_hash_sh := $(srctree)/scripts/orc_hash.sh
340targets += $(orc_hash_h)
341quiet_cmd_orc_hash = GEN $@
342 cmd_orc_hash = mkdir -p $(dir $@); \
343 $(CONFIG_SHELL) $(orc_hash_sh) < $< > $@
344$(orc_hash_h): $(srctree)/arch/x86/include/asm/orc_types.h $(orc_hash_sh) FORCE
345 $(call if_changed,orc_hash)
346archprepare: $(orc_hash_h)
347endif
348
349archclean:
350 $(Q)rm -rf $(objtree)/arch/i386
351 $(Q)rm -rf $(objtree)/arch/x86_64
352
353define archhelp
354 echo '* bzImage - Compressed kernel image (arch/x86/boot/bzImage)'
355 echo ' install - Install kernel using (your) ~/bin/$(INSTALLKERNEL) or'
356 echo ' (distribution) /sbin/$(INSTALLKERNEL) or install to '
357 echo ' $$(INSTALL_PATH) and run lilo'
358 echo ''
359 echo ' fdimage - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)'
360 echo ' fdimage144 - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)'
361 echo ' fdimage288 - Create 2.8MB boot floppy image (arch/x86/boot/fdimage)'
362 echo ' hdimage - Create a BIOS/EFI hard disk image (arch/x86/boot/hdimage)'
363 echo ' isoimage - Create a boot CD-ROM image (arch/x86/boot/image.iso)'
364 echo ' bzdisk/fdimage*/hdimage/isoimage also accept:'
365 echo ' FDARGS="..." arguments for the booted kernel'
366 echo ' FDINITRD=file initrd for the booted kernel'
367
368endef
1# SPDX-License-Identifier: GPL-2.0
2# Unified Makefile for i386 and x86_64
3
4# select defconfig based on actual architecture
5ifeq ($(ARCH),x86)
6 ifeq ($(shell uname -m),x86_64)
7 KBUILD_DEFCONFIG := x86_64_defconfig
8 else
9 KBUILD_DEFCONFIG := i386_defconfig
10 endif
11else
12 KBUILD_DEFCONFIG := $(ARCH)_defconfig
13endif
14
15# For gcc stack alignment is specified with -mpreferred-stack-boundary,
16# clang has the option -mstack-alignment for that purpose.
17ifneq ($(call cc-option, -mpreferred-stack-boundary=4),)
18 cc_stack_align4 := -mpreferred-stack-boundary=2
19 cc_stack_align8 := -mpreferred-stack-boundary=3
20else ifneq ($(call cc-option, -mstack-alignment=16),)
21 cc_stack_align4 := -mstack-alignment=4
22 cc_stack_align8 := -mstack-alignment=8
23endif
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.
31CODE16GCC_CFLAGS := -m32 -Wa,$(srctree)/arch/x86/boot/code16gcc.h
32M16_CFLAGS := $(call cc-option, -m16, $(CODE16GCC_CFLAGS))
33
34REALMODE_CFLAGS := $(M16_CFLAGS) -g -Os -DDISABLE_BRANCH_PROFILING \
35 -Wall -Wstrict-prototypes -march=i386 -mregparm=3 \
36 -fno-strict-aliasing -fomit-frame-pointer -fno-pic \
37 -mno-mmx -mno-sse
38
39REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -ffreestanding)
40REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -fno-stack-protector)
41REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), $(cc_stack_align4))
42export REALMODE_CFLAGS
43
44# BITS is used as extension for files which are available in a 32 bit
45# and a 64 bit version to simplify shared Makefiles.
46# e.g.: obj-y += foo_$(BITS).o
47export BITS
48
49ifdef CONFIG_X86_NEED_RELOCS
50 LDFLAGS_vmlinux := --emit-relocs
51endif
52
53#
54# Prevent GCC from generating any FP code by mistake.
55#
56# This must happen before we try the -mpreferred-stack-boundary, see:
57#
58# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383
59#
60KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow
61KBUILD_CFLAGS += $(call cc-option,-mno-avx,)
62
63ifeq ($(CONFIG_X86_32),y)
64 BITS := 32
65 UTS_MACHINE := i386
66 CHECKFLAGS += -D__i386__
67
68 biarch := $(call cc-option,-m32)
69 KBUILD_AFLAGS += $(biarch)
70 KBUILD_CFLAGS += $(biarch)
71
72 KBUILD_CFLAGS += -msoft-float -mregparm=3 -freg-struct-return
73
74 # Never want PIC in a 32-bit kernel, prevent breakage with GCC built
75 # with nonstandard options
76 KBUILD_CFLAGS += -fno-pic
77
78 # Align the stack to the register width instead of using the default
79 # alignment of 16 bytes. This reduces stack usage and the number of
80 # alignment instructions.
81 KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align4))
82
83 # Disable unit-at-a-time mode on pre-gcc-4.0 compilers, it makes gcc use
84 # a lot more stack due to the lack of sharing of stacklots:
85 KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0400, \
86 $(call cc-option,-fno-unit-at-a-time))
87
88 # CPU-specific tuning. Anything which can be shared with UML should go here.
89 include arch/x86/Makefile_32.cpu
90 KBUILD_CFLAGS += $(cflags-y)
91
92 # temporary until string.h is fixed
93 KBUILD_CFLAGS += -ffreestanding
94else
95 BITS := 64
96 UTS_MACHINE := x86_64
97 CHECKFLAGS += -D__x86_64__ -m64
98
99 biarch := -m64
100 KBUILD_AFLAGS += -m64
101 KBUILD_CFLAGS += -m64
102
103 # Align jump targets to 1 byte, not the default 16 bytes:
104 KBUILD_CFLAGS += $(call cc-option,-falign-jumps=1)
105
106 # Pack loops tightly as well:
107 KBUILD_CFLAGS += $(call cc-option,-falign-loops=1)
108
109 # Don't autogenerate traditional x87 instructions
110 KBUILD_CFLAGS += $(call cc-option,-mno-80387)
111 KBUILD_CFLAGS += $(call cc-option,-mno-fp-ret-in-387)
112
113 # By default gcc and clang use a stack alignment of 16 bytes for x86.
114 # However the standard kernel entry on x86-64 leaves the stack on an
115 # 8-byte boundary. If the compiler isn't informed about the actual
116 # alignment it will generate extra alignment instructions for the
117 # default alignment which keep the stack *mis*aligned.
118 # Furthermore an alignment to the register width reduces stack usage
119 # and the number of alignment instructions.
120 KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align8))
121
122 # Use -mskip-rax-setup if supported.
123 KBUILD_CFLAGS += $(call cc-option,-mskip-rax-setup)
124
125 # FIXME - should be integrated in Makefile.cpu (Makefile_32.cpu)
126 cflags-$(CONFIG_MK8) += $(call cc-option,-march=k8)
127 cflags-$(CONFIG_MPSC) += $(call cc-option,-march=nocona)
128
129 cflags-$(CONFIG_MCORE2) += \
130 $(call cc-option,-march=core2,$(call cc-option,-mtune=generic))
131 cflags-$(CONFIG_MATOM) += $(call cc-option,-march=atom) \
132 $(call cc-option,-mtune=atom,$(call cc-option,-mtune=generic))
133 cflags-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=generic)
134 KBUILD_CFLAGS += $(cflags-y)
135
136 KBUILD_CFLAGS += -mno-red-zone
137 KBUILD_CFLAGS += -mcmodel=kernel
138
139 # -funit-at-a-time shrinks the kernel .text considerably
140 # unfortunately it makes reading oopses harder.
141 KBUILD_CFLAGS += $(call cc-option,-funit-at-a-time)
142endif
143
144ifdef CONFIG_X86_X32
145 x32_ld_ok := $(call try-run,\
146 /bin/echo -e '1: .quad 1b' | \
147 $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" - && \
148 $(OBJCOPY) -O elf32-x86-64 "$$TMP" "$$TMPO" && \
149 $(LD) -m elf32_x86_64 "$$TMPO" -o "$$TMP",y,n)
150 ifeq ($(x32_ld_ok),y)
151 CONFIG_X86_X32_ABI := y
152 KBUILD_AFLAGS += -DCONFIG_X86_X32_ABI
153 KBUILD_CFLAGS += -DCONFIG_X86_X32_ABI
154 else
155 $(warning CONFIG_X86_X32 enabled but no binutils support)
156 endif
157endif
158export CONFIG_X86_X32_ABI
159
160#
161# If the function graph tracer is used with mcount instead of fentry,
162# '-maccumulate-outgoing-args' is needed to prevent a GCC bug
163# (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=42109)
164#
165ifdef CONFIG_FUNCTION_GRAPH_TRACER
166 ifndef CONFIG_HAVE_FENTRY
167 ACCUMULATE_OUTGOING_ARGS := 1
168 else
169 ifeq ($(call cc-option-yn, -mfentry), n)
170 ACCUMULATE_OUTGOING_ARGS := 1
171
172 # GCC ignores '-maccumulate-outgoing-args' when used with '-Os'.
173 # If '-Os' is enabled, disable it and print a warning.
174 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
175 undefine CONFIG_CC_OPTIMIZE_FOR_SIZE
176 $(warning Disabling CONFIG_CC_OPTIMIZE_FOR_SIZE. Your compiler does not have -mfentry so you cannot optimize for size with CONFIG_FUNCTION_GRAPH_TRACER.)
177 endif
178
179 endif
180 endif
181endif
182
183ifndef CC_HAVE_ASM_GOTO
184 $(error Compiler lacks asm-goto support.)
185endif
186
187#
188# Jump labels need '-maccumulate-outgoing-args' for gcc < 4.5.2 to prevent a
189# GCC bug (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=46226). There's no way
190# to test for this bug at compile-time because the test case needs to execute,
191# which is a no-go for cross compilers. So check the GCC version instead.
192#
193ifdef CONFIG_JUMP_LABEL
194 ifneq ($(ACCUMULATE_OUTGOING_ARGS), 1)
195 ACCUMULATE_OUTGOING_ARGS = $(call cc-if-fullversion, -lt, 040502, 1)
196 endif
197endif
198
199ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1)
200 # This compiler flag is not supported by Clang:
201 KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args,)
202endif
203
204# Stackpointer is addressed different for 32 bit and 64 bit x86
205sp-$(CONFIG_X86_32) := esp
206sp-$(CONFIG_X86_64) := rsp
207
208# do binutils support CFI?
209cfi := $(call as-instr,.cfi_startproc\n.cfi_rel_offset $(sp-y)$(comma)0\n.cfi_endproc,-DCONFIG_AS_CFI=1)
210# is .cfi_signal_frame supported too?
211cfi-sigframe := $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1)
212cfi-sections := $(call as-instr,.cfi_sections .debug_frame,-DCONFIG_AS_CFI_SECTIONS=1)
213
214# does binutils support specific instructions?
215asinstr := $(call as-instr,fxsaveq (%rax),-DCONFIG_AS_FXSAVEQ=1)
216asinstr += $(call as-instr,pshufb %xmm0$(comma)%xmm0,-DCONFIG_AS_SSSE3=1)
217asinstr += $(call as-instr,crc32l %eax$(comma)%eax,-DCONFIG_AS_CRC32=1)
218avx_instr := $(call as-instr,vxorps %ymm0$(comma)%ymm1$(comma)%ymm2,-DCONFIG_AS_AVX=1)
219avx2_instr :=$(call as-instr,vpbroadcastb %xmm0$(comma)%ymm1,-DCONFIG_AS_AVX2=1)
220avx512_instr :=$(call as-instr,vpmovm2b %k1$(comma)%zmm5,-DCONFIG_AS_AVX512=1)
221sha1_ni_instr :=$(call as-instr,sha1msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA1_NI=1)
222sha256_ni_instr :=$(call as-instr,sha256msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA256_NI=1)
223
224KBUILD_AFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr)
225KBUILD_CFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr)
226
227LDFLAGS := -m elf_$(UTS_MACHINE)
228
229#
230# The 64-bit kernel must be aligned to 2MB. Pass -z max-page-size=0x200000 to
231# the linker to force 2MB page size regardless of the default page size used
232# by the linker.
233#
234ifdef CONFIG_X86_64
235LDFLAGS += $(call ld-option, -z max-page-size=0x200000)
236endif
237
238# Speed up the build
239KBUILD_CFLAGS += -pipe
240# Workaround for a gcc prelease that unfortunately was shipped in a suse release
241KBUILD_CFLAGS += -Wno-sign-compare
242#
243KBUILD_CFLAGS += -fno-asynchronous-unwind-tables
244
245# Avoid indirect branches in kernel to deal with Spectre
246ifdef CONFIG_RETPOLINE
247ifneq ($(RETPOLINE_CFLAGS),)
248 KBUILD_CFLAGS += $(RETPOLINE_CFLAGS) -DRETPOLINE
249endif
250endif
251
252archscripts: scripts_basic
253 $(Q)$(MAKE) $(build)=arch/x86/tools relocs
254
255###
256# Syscall table generation
257
258archheaders:
259 $(Q)$(MAKE) $(build)=arch/x86/entry/syscalls all
260
261archprepare:
262ifeq ($(CONFIG_KEXEC_FILE),y)
263 $(Q)$(MAKE) $(build)=arch/x86/purgatory arch/x86/purgatory/kexec-purgatory.c
264endif
265
266###
267# Kernel objects
268
269head-y := arch/x86/kernel/head_$(BITS).o
270head-y += arch/x86/kernel/head$(BITS).o
271head-y += arch/x86/kernel/ebda.o
272head-y += arch/x86/kernel/platform-quirks.o
273
274libs-y += arch/x86/lib
275
276# See arch/x86/Kbuild for content of core part of the kernel
277core-y += arch/x86/
278
279# drivers-y are linked after core-y
280drivers-$(CONFIG_MATH_EMULATION) += arch/x86/math-emu/
281drivers-$(CONFIG_PCI) += arch/x86/pci/
282
283# must be linked after kernel
284drivers-$(CONFIG_OPROFILE) += arch/x86/oprofile/
285
286# suspend and hibernation support
287drivers-$(CONFIG_PM) += arch/x86/power/
288
289drivers-$(CONFIG_FB) += arch/x86/video/
290
291####
292# boot loader support. Several targets are kept for legacy purposes
293
294boot := arch/x86/boot
295
296BOOT_TARGETS = bzlilo bzdisk fdimage fdimage144 fdimage288 isoimage
297
298PHONY += bzImage $(BOOT_TARGETS)
299
300# Default kernel to build
301all: bzImage
302
303# KBUILD_IMAGE specify target image being built
304KBUILD_IMAGE := $(boot)/bzImage
305
306bzImage: vmlinux
307ifeq ($(CONFIG_X86_DECODER_SELFTEST),y)
308 $(Q)$(MAKE) $(build)=arch/x86/tools posttest
309endif
310 $(Q)$(MAKE) $(build)=$(boot) $(KBUILD_IMAGE)
311 $(Q)mkdir -p $(objtree)/arch/$(UTS_MACHINE)/boot
312 $(Q)ln -fsn ../../x86/boot/bzImage $(objtree)/arch/$(UTS_MACHINE)/boot/$@
313
314$(BOOT_TARGETS): vmlinux
315 $(Q)$(MAKE) $(build)=$(boot) $@
316
317PHONY += install
318install:
319 $(Q)$(MAKE) $(build)=$(boot) $@
320
321PHONY += vdso_install
322vdso_install:
323 $(Q)$(MAKE) $(build)=arch/x86/entry/vdso $@
324
325archclean:
326 $(Q)rm -rf $(objtree)/arch/i386
327 $(Q)rm -rf $(objtree)/arch/x86_64
328 $(Q)$(MAKE) $(clean)=$(boot)
329 $(Q)$(MAKE) $(clean)=arch/x86/tools
330 $(Q)$(MAKE) $(clean)=arch/x86/purgatory
331
332define archhelp
333 echo '* bzImage - Compressed kernel image (arch/x86/boot/bzImage)'
334 echo ' install - Install kernel using'
335 echo ' (your) ~/bin/$(INSTALLKERNEL) or'
336 echo ' (distribution) /sbin/$(INSTALLKERNEL) or'
337 echo ' install to $$(INSTALL_PATH) and run lilo'
338 echo ' fdimage - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)'
339 echo ' fdimage144 - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)'
340 echo ' fdimage288 - Create 2.8MB boot floppy image (arch/x86/boot/fdimage)'
341 echo ' isoimage - Create a boot CD-ROM image (arch/x86/boot/image.iso)'
342 echo ' bzdisk/fdimage*/isoimage also accept:'
343 echo ' FDARGS="..." arguments for the booted kernel'
344 echo ' FDINITRD=file initrd for the booted kernel'
345endef