Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

Open Menu /arch/x86/boot/compressed/Makefile 
  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
#
# linux/arch/x86/boot/compressed/Makefile
#
# create a compressed vmlinux image from the original vmlinux
#
# vmlinuz is:
#	decompression code (*.o)
#	asm globals (piggy.S), including:
#		vmlinux.bin.(gz|bz2|lzma|...)
#
# vmlinux.bin is:
#	vmlinux stripped of debugging and comments
# vmlinux.bin.all is:
#	vmlinux.bin + vmlinux.relocs
# vmlinux.bin.(gz|bz2|lzma|...) is:
#	(see scripts/Makefile.lib size_append)
#	compressed vmlinux.bin.all + u32 size of vmlinux.bin.all

KASAN_SANITIZE			:= n
OBJECT_FILES_NON_STANDARD	:= y

# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
KCOV_INSTRUMENT		:= n

targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
	vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4

KBUILD_CFLAGS := -m$(BITS) -D__KERNEL__ -O2
KBUILD_CFLAGS += -fno-strict-aliasing $(call cc-option, -fPIE, -fPIC)
KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING
cflags-$(CONFIG_X86_32) := -march=i386
cflags-$(CONFIG_X86_64) := -mcmodel=small
KBUILD_CFLAGS += $(cflags-y)
KBUILD_CFLAGS += -mno-mmx -mno-sse
KBUILD_CFLAGS += $(call cc-option,-ffreestanding)
KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector)

KBUILD_AFLAGS  := $(KBUILD_CFLAGS) -D__ASSEMBLY__
KBUILD_CFLAGS  += -include $(srctree)/include/linux/lockdoc.h -DX86_BOOT_CODE
GCOV_PROFILE := n
UBSAN_SANITIZE :=n

LDFLAGS := -m elf_$(UTS_MACHINE)
# Compressed kernel should be built as PIE since it may be loaded at any
# address by the bootloader.
ifeq ($(CONFIG_X86_32),y)
LDFLAGS += $(call ld-option, -pie) $(call ld-option, --no-dynamic-linker)
else
# To build 64-bit compressed kernel as PIE, we disable relocation
# overflow check to avoid relocation overflow error with a new linker
# command-line option, -z noreloc-overflow.
LDFLAGS += $(shell $(LD) --help 2>&1 | grep -q "\-z noreloc-overflow" \
	&& echo "-z noreloc-overflow -pie --no-dynamic-linker")
endif
LDFLAGS_vmlinux := -T

hostprogs-y	:= mkpiggy
HOST_EXTRACFLAGS += -I$(srctree)/tools/include

sed-voffset := -e 's/^\([0-9a-fA-F]*\) [ABCDGRSTVW] \(_text\|__bss_start\|_end\)$$/\#define VO_\2 _AC(0x\1,UL)/p'

quiet_cmd_voffset = VOFFSET $@
      cmd_voffset = $(NM) $< | sed -n $(sed-voffset) > $@

targets += ../voffset.h

$(obj)/../voffset.h: vmlinux FORCE
	$(call if_changed,voffset)

$(obj)/misc.o: $(obj)/../voffset.h

vmlinux-objs-y := $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \
	$(obj)/string.o $(obj)/cmdline.o $(obj)/error.o \
	$(obj)/piggy.o $(obj)/cpuflags.o

vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o
vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o
ifdef CONFIG_X86_64
	vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/pagetable.o
endif

$(obj)/eboot.o: KBUILD_CFLAGS += -fshort-wchar -mno-red-zone

vmlinux-objs-$(CONFIG_EFI_STUB) += $(obj)/eboot.o $(obj)/efi_stub_$(BITS).o \
	$(objtree)/drivers/firmware/efi/libstub/lib.a
vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_thunk_$(BITS).o

# The compressed kernel is built with -fPIC/-fPIE so that a boot loader
# can place it anywhere in memory and it will still run. However, since
# it is executed as-is without any ELF relocation processing performed
# (and has already had all relocation sections stripped from the binary),
# none of the code can use data relocations (e.g. static assignments of
# pointer values), since they will be meaningless at runtime. This check
# will refuse to link the vmlinux if any of these relocations are found.
quiet_cmd_check_data_rel = DATAREL $@
define cmd_check_data_rel
	for obj in $(filter %.o,$^); do \
		readelf -S $$obj | grep -qF .rel.local && { \
			echo "error: $$obj has data relocations!" >&2; \
			exit 1; \
		} || true; \
	done
endef

$(obj)/vmlinux: $(vmlinux-objs-y) FORCE
	$(call if_changed,check_data_rel)
	$(call if_changed,ld)

OBJCOPYFLAGS_vmlinux.bin :=  -R .comment -S
$(obj)/vmlinux.bin: vmlinux FORCE
	$(call if_changed,objcopy)

targets += $(patsubst $(obj)/%,%,$(vmlinux-objs-y)) vmlinux.bin.all vmlinux.relocs

CMD_RELOCS = arch/x86/tools/relocs
quiet_cmd_relocs = RELOCS  $@
      cmd_relocs = $(CMD_RELOCS) $< > $@;$(CMD_RELOCS) --abs-relocs $<
$(obj)/vmlinux.relocs: vmlinux FORCE
	$(call if_changed,relocs)

vmlinux.bin.all-y := $(obj)/vmlinux.bin
vmlinux.bin.all-$(CONFIG_X86_NEED_RELOCS) += $(obj)/vmlinux.relocs

$(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE
	$(call if_changed,gzip)
$(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y) FORCE
	$(call if_changed,bzip2)
$(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y) FORCE
	$(call if_changed,lzma)
$(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y) FORCE
	$(call if_changed,xzkern)
$(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y) FORCE
	$(call if_changed,lzo)
$(obj)/vmlinux.bin.lz4: $(vmlinux.bin.all-y) FORCE
	$(call if_changed,lz4)

suffix-$(CONFIG_KERNEL_GZIP)	:= gz
suffix-$(CONFIG_KERNEL_BZIP2)	:= bz2
suffix-$(CONFIG_KERNEL_LZMA)	:= lzma
suffix-$(CONFIG_KERNEL_XZ)	:= xz
suffix-$(CONFIG_KERNEL_LZO) 	:= lzo
suffix-$(CONFIG_KERNEL_LZ4) 	:= lz4

quiet_cmd_mkpiggy = MKPIGGY $@
      cmd_mkpiggy = $(obj)/mkpiggy $< > $@ || ( rm -f $@ ; false )

targets += piggy.S
$(obj)/piggy.S: $(obj)/vmlinux.bin.$(suffix-y) $(obj)/mkpiggy FORCE
	$(call if_changed,mkpiggy)