1 # SPDX-License-Identifier: GPL-2.0
3 # linux/arch/x86/boot/compressed/Makefile
5 # create a compressed vmlinux image from the original vmlinux
8 # decompression code (*.o)
9 # asm globals (piggy.S), including:
10 # vmlinux.bin.(gz|bz2|lzma|...)
13 # vmlinux stripped of debugging and comments
15 # vmlinux.bin + vmlinux.relocs
16 # vmlinux.bin.(gz|bz2|lzma|...) is:
17 # (see scripts/Makefile.lib size_append)
18 # compressed vmlinux.bin.all + u32 size of vmlinux.bin.all
21 OBJECT_FILES_NON_STANDARD
:= y
23 # Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
26 targets
:= vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
27 vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4
29 KBUILD_CFLAGS
:= -m
$(BITS
) -D__KERNEL__
-O2
30 KBUILD_CFLAGS
+= -fno-strict-aliasing
$(call cc-option
, -fPIE
, -fPIC
)
31 KBUILD_CFLAGS
+= -DDISABLE_BRANCH_PROFILING
32 cflags-
$(CONFIG_X86_32
) := -march
=i386
33 cflags-
$(CONFIG_X86_64
) := -mcmodel
=small
34 KBUILD_CFLAGS
+= $(cflags-y
)
35 KBUILD_CFLAGS
+= -mno-mmx
-mno-sse
36 KBUILD_CFLAGS
+= $(call cc-option
,-ffreestanding
)
37 KBUILD_CFLAGS
+= $(call cc-option
,-fno-stack-protector
)
38 KBUILD_CFLAGS
+= $(call cc-disable-warning
, address-of-packed-member
)
39 KBUILD_CFLAGS
+= $(call cc-disable-warning
, gnu
)
41 KBUILD_AFLAGS
:= $(KBUILD_CFLAGS
) -D__ASSEMBLY__
45 LDFLAGS
:= -m elf_
$(UTS_MACHINE
)
46 # Compressed kernel should be built as PIE since it may be loaded at any
47 # address by the bootloader.
48 ifeq ($(CONFIG_X86_32
),y
)
49 LDFLAGS
+= $(call ld-option
, -pie
) $(call ld-option
, --no-dynamic-linker
)
51 # To build 64-bit compressed kernel as PIE, we disable relocation
52 # overflow check to avoid relocation overflow error with a new linker
53 # command-line option, -z noreloc-overflow.
54 LDFLAGS
+= $(shell $(LD
) --help
2>&1 | grep
-q
"\-z noreloc-overflow" \
55 && echo
"-z noreloc-overflow -pie --no-dynamic-linker")
59 hostprogs-y
:= mkpiggy
60 HOST_EXTRACFLAGS
+= -I
$(srctree
)/tools
/include
62 sed-voffset
:= -e
's/^\([0-9a-fA-F]*\) [ABCDGRSTVW] \(_text\|__bss_start\|_end\)$$/\#define VO_\2 _AC(0x\1,UL)/p'
64 quiet_cmd_voffset
= VOFFSET
$@
65 cmd_voffset
= $(NM
) $< | sed
-n
$(sed-voffset
) > $@
67 targets
+= ..
/voffset.h
69 $(obj
)/..
/voffset.h
: vmlinux FORCE
70 $(call if_changed
,voffset
)
72 $(obj
)/misc.o
: $(obj
)/..
/voffset.h
74 vmlinux-objs-y
:= $(obj
)/vmlinux.lds
$(obj
)/head_
$(BITS
).o
$(obj
)/misc.o \
75 $(obj
)/string.o
$(obj
)/cmdline.o
$(obj
)/error.o \
76 $(obj
)/piggy.o
$(obj
)/cpuflags.o
78 vmlinux-objs-
$(CONFIG_EARLY_PRINTK
) += $(obj
)/early_serial_console.o
79 vmlinux-objs-
$(CONFIG_RANDOMIZE_BASE
) += $(obj
)/kaslr.o
81 vmlinux-objs-
$(CONFIG_RANDOMIZE_BASE
) += $(obj
)/pagetable.o
82 vmlinux-objs-y
+= $(obj
)/mem_encrypt.o
85 $(obj
)/eboot.o
: KBUILD_CFLAGS
+= -fshort-wchar
-mno-red-zone
87 vmlinux-objs-
$(CONFIG_EFI_STUB
) += $(obj
)/eboot.o
$(obj
)/efi_stub_
$(BITS
).o \
88 $(objtree
)/drivers
/firmware
/efi
/libstub
/lib.a
89 vmlinux-objs-
$(CONFIG_EFI_MIXED
) += $(obj
)/efi_thunk_
$(BITS
).o
91 # The compressed kernel is built with -fPIC/-fPIE so that a boot loader
92 # can place it anywhere in memory and it will still run. However, since
93 # it is executed as-is without any ELF relocation processing performed
94 # (and has already had all relocation sections stripped from the binary),
95 # none of the code can use data relocations (e.g. static assignments of
96 # pointer values), since they will be meaningless at runtime. This check
97 # will refuse to link the vmlinux if any of these relocations are found.
98 quiet_cmd_check_data_rel
= DATAREL
$@
99 define cmd_check_data_rel
100 for obj in
$(filter %.o
,$^
); do \
101 ${CROSS_COMPILE}readelf
-S
$$obj | grep
-qF .rel.local
&& { \
102 echo
"error: $$obj has data relocations!" >&2; \
108 $(obj
)/vmlinux
: $(vmlinux-objs-y
) FORCE
109 $(call if_changed
,check_data_rel
)
110 $(call if_changed
,ld)
112 OBJCOPYFLAGS_vmlinux.bin
:= -R .comment
-S
113 $(obj
)/vmlinux.bin
: vmlinux FORCE
114 $(call if_changed
,objcopy
)
116 targets
+= $(patsubst $(obj
)/%,%,$(vmlinux-objs-y
)) vmlinux.bin.
all vmlinux.relocs
118 CMD_RELOCS
= arch
/x86
/tools
/relocs
119 quiet_cmd_relocs
= RELOCS
$@
120 cmd_relocs
= $(CMD_RELOCS
) $< > $@
;$(CMD_RELOCS
) --abs-relocs
$<
121 $(obj
)/vmlinux.relocs
: vmlinux FORCE
122 $(call if_changed
,relocs
)
124 vmlinux.bin.all-y
:= $(obj
)/vmlinux.bin
125 vmlinux.bin.all-
$(CONFIG_X86_NEED_RELOCS
) += $(obj
)/vmlinux.relocs
127 $(obj
)/vmlinux.bin.gz
: $(vmlinux.bin.all-y
) FORCE
128 $(call if_changed
,gzip
)
129 $(obj
)/vmlinux.bin.bz2
: $(vmlinux.bin.all-y
) FORCE
130 $(call if_changed
,bzip2
)
131 $(obj
)/vmlinux.bin.lzma
: $(vmlinux.bin.all-y
) FORCE
132 $(call if_changed
,lzma
)
133 $(obj
)/vmlinux.bin.xz
: $(vmlinux.bin.all-y
) FORCE
134 $(call if_changed
,xzkern
)
135 $(obj
)/vmlinux.bin.lzo
: $(vmlinux.bin.all-y
) FORCE
136 $(call if_changed
,lzo
)
137 $(obj
)/vmlinux.bin.lz4
: $(vmlinux.bin.all-y
) FORCE
138 $(call if_changed
,lz4
)
140 suffix-
$(CONFIG_KERNEL_GZIP
) := gz
141 suffix-
$(CONFIG_KERNEL_BZIP2
) := bz2
142 suffix-
$(CONFIG_KERNEL_LZMA
) := lzma
143 suffix-
$(CONFIG_KERNEL_XZ
) := xz
144 suffix-
$(CONFIG_KERNEL_LZO
) := lzo
145 suffix-
$(CONFIG_KERNEL_LZ4
) := lz4
147 quiet_cmd_mkpiggy
= MKPIGGY
$@
148 cmd_mkpiggy
= $(obj
)/mkpiggy
$< > $@ ||
( rm -f
$@
; false
)
151 $(obj
)/piggy.S
: $(obj
)/vmlinux.bin.
$(suffix-y
) $(obj
)/mkpiggy FORCE
152 $(call if_changed
,mkpiggy
)