2 # linux/arch/x86/boot/compressed/Makefile
4 # create a compressed vmlinux image from the original vmlinux
7 # decompression code (*.o)
8 # asm globals (piggy.S), including:
9 # vmlinux.bin.(gz|bz2|lzma|...)
12 # vmlinux stripped of debugging and comments
14 # vmlinux.bin + vmlinux.relocs
15 # vmlinux.bin.(gz|bz2|lzma|...) is:
16 # (see scripts/Makefile.lib size_append)
17 # compressed vmlinux.bin.all + u32 size of vmlinux.bin.all
20 OBJECT_FILES_NON_STANDARD := y
22 # Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
25 targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
26 vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4
28 KBUILD_CFLAGS := -m$(BITS) -D__KERNEL__ -O2
29 KBUILD_CFLAGS += -fno-strict-aliasing $(call cc-option, -fPIE, -fPIC)
30 KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING
31 cflags-$(CONFIG_X86_32) := -march=i386
32 cflags-$(CONFIG_X86_64) := -mcmodel=small
33 KBUILD_CFLAGS += $(cflags-y)
34 KBUILD_CFLAGS += -mno-mmx -mno-sse
35 KBUILD_CFLAGS += $(call cc-option,-ffreestanding)
36 KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector)
38 KBUILD_AFLAGS := $(KBUILD_CFLAGS) -D__ASSEMBLY__
42 LDFLAGS := -m elf_$(UTS_MACHINE)
43 # Compressed kernel should be built as PIE since it may be loaded at any
44 # address by the bootloader.
45 ifeq ($(CONFIG_X86_32),y)
46 LDFLAGS += $(call ld-option, -pie) $(call ld-option, --no-dynamic-linker)
48 # To build 64-bit compressed kernel as PIE, we disable relocation
49 # overflow check to avoid relocation overflow error with a new linker
50 # command-line option, -z noreloc-overflow.
51 LDFLAGS += $(shell $(LD) --help 2>&1 | grep -q "\-z noreloc-overflow" \
52 && echo "-z noreloc-overflow -pie --no-dynamic-linker")
56 hostprogs-y := mkpiggy
57 HOST_EXTRACFLAGS += -I$(srctree)/tools/include
59 sed-voffset := -e 's/^\([0-9a-fA-F]*\) [ABCDGRSTVW] \(_text\|__bss_start\|_end\)$$/\#define VO_\2 _AC(0x\1,UL)/p'
61 quiet_cmd_voffset = VOFFSET $@
62 cmd_voffset = $(NM) $< | sed -n $(sed-voffset) > $@
64 targets += ../voffset.h
66 $(obj)/../voffset.h: vmlinux FORCE
67 $(call if_changed,voffset)
69 $(obj)/misc.o: $(obj)/../voffset.h
71 vmlinux-objs-y := $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \
72 $(obj)/string.o $(obj)/cmdline.o $(obj)/error.o \
73 $(obj)/piggy.o $(obj)/cpuflags.o
75 vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o
76 vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o
78 vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/pagetable.o
81 $(obj)/eboot.o: KBUILD_CFLAGS += -fshort-wchar -mno-red-zone
83 vmlinux-objs-$(CONFIG_EFI_STUB) += $(obj)/eboot.o $(obj)/efi_stub_$(BITS).o \
84 $(objtree)/drivers/firmware/efi/libstub/lib.a
85 vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_thunk_$(BITS).o
87 # The compressed kernel is built with -fPIC/-fPIE so that a boot loader
88 # can place it anywhere in memory and it will still run. However, since
89 # it is executed as-is without any ELF relocation processing performed
90 # (and has already had all relocation sections stripped from the binary),
91 # none of the code can use data relocations (e.g. static assignments of
92 # pointer values), since they will be meaningless at runtime. This check
93 # will refuse to link the vmlinux if any of these relocations are found.
94 quiet_cmd_check_data_rel = DATAREL $@
95 define cmd_check_data_rel
96 for obj in $(filter %.o,$^); do \
97 ${CROSS_COMPILE}readelf -S $$obj | grep -qF .rel.local && { \
98 echo "error: $$obj has data relocations!" >&2; \
104 $(obj)/vmlinux: $(vmlinux-objs-y) FORCE
105 $(call if_changed,check_data_rel)
106 $(call if_changed,ld)
108 OBJCOPYFLAGS_vmlinux.bin := -R .comment -S
109 $(obj)/vmlinux.bin: vmlinux FORCE
110 $(call if_changed,objcopy)
112 targets += $(patsubst $(obj)/%,%,$(vmlinux-objs-y)) vmlinux.bin.all vmlinux.relocs
114 CMD_RELOCS = arch/x86/tools/relocs
115 quiet_cmd_relocs = RELOCS $@
116 cmd_relocs = $(CMD_RELOCS) $< > $@;$(CMD_RELOCS) --abs-relocs $<
117 $(obj)/vmlinux.relocs: vmlinux FORCE
118 $(call if_changed,relocs)
120 vmlinux.bin.all-y := $(obj)/vmlinux.bin
121 vmlinux.bin.all-$(CONFIG_X86_NEED_RELOCS) += $(obj)/vmlinux.relocs
123 $(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE
124 $(call if_changed,gzip)
125 $(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y) FORCE
126 $(call if_changed,bzip2)
127 $(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y) FORCE
128 $(call if_changed,lzma)
129 $(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y) FORCE
130 $(call if_changed,xzkern)
131 $(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y) FORCE
132 $(call if_changed,lzo)
133 $(obj)/vmlinux.bin.lz4: $(vmlinux.bin.all-y) FORCE
134 $(call if_changed,lz4)
136 suffix-$(CONFIG_KERNEL_GZIP) := gz
137 suffix-$(CONFIG_KERNEL_BZIP2) := bz2
138 suffix-$(CONFIG_KERNEL_LZMA) := lzma
139 suffix-$(CONFIG_KERNEL_XZ) := xz
140 suffix-$(CONFIG_KERNEL_LZO) := lzo
141 suffix-$(CONFIG_KERNEL_LZ4) := lz4
143 quiet_cmd_mkpiggy = MKPIGGY $@
144 cmd_mkpiggy = $(obj)/mkpiggy $< > $@ || ( rm -f $@ ; false )
147 $(obj)/piggy.S: $(obj)/vmlinux.bin.$(suffix-y) $(obj)/mkpiggy FORCE
148 $(call if_changed,mkpiggy)