arch/x86/boot/compressed/Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 #
   3 # linux/arch/x86/boot/compressed/Makefile
   4 #
   5 # create a compressed vmlinux image from the original vmlinux
   6 #
   7 # vmlinuz is:
   8 #       decompression code (*.o)
   9 #       asm globals (piggy.S), including:
  10 #               vmlinux.bin.(gz|bz2|lzma|...)
  11 #
  12 # vmlinux.bin is:
  13 #       vmlinux stripped of debugging and comments
  14 # vmlinux.bin.all is:
  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
  19
  20 KASAN_SANITIZE                  := n
  21 OBJECT_FILES_NON_STANDARD       := y
  22
  23 # Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
  24 KCOV_INSTRUMENT         := n
  25
  26 targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
  27         vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4
  28
  29 KBUILD_CFLAGS := -m$(BITS) -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)
  40
  41 KBUILD_AFLAGS  := $(KBUILD_CFLAGS) -D__ASSEMBLY__
  42 GCOV_PROFILE := n
  43 UBSAN_SANITIZE :=n
  44
  45 LDFLAGS := -m elf_$(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)
  50 else
  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 $(LD) --help 2>&1 | grep -q "\-z noreloc-overflow" \
  55         && echo "-z noreloc-overflow -pie --no-dynamic-linker")
  56 endif
  57 LDFLAGS_vmlinux := -T
  58
  59 hostprogs-y     := mkpiggy
  60 HOST_EXTRACFLAGS += -I$(srctree)/tools/include
  61
  62 sed-voffset := -e 's/^\([0-9a-fA-F]*\) [ABCDGRSTVW] \(_text\|__bss_start\|_end\)$$/\#define VO_\2 _AC(0x\1,UL)/p'
  63
  64 quiet_cmd_voffset = VOFFSET $@
  65       cmd_voffset = $(NM) $< | sed -n $(sed-voffset) > $@
  66
  67 targets += ../voffset.h
  68
  69 $(obj)/../voffset.h: vmlinux FORCE
  70         $(call if_changed,voffset)
  71
  72 $(obj)/misc.o: $(obj)/../voffset.h
  73
  74 vmlinux-objs-y := $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \
  75         $(obj)/string.o $(obj)/cmdline.o $(obj)/error.o \
  76         $(obj)/piggy.o $(obj)/cpuflags.o
  77
  78 vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o
  79 vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o
  80 ifdef CONFIG_X86_64
  81         vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr_64.o
  82         vmlinux-objs-y += $(obj)/mem_encrypt.o
  83         vmlinux-objs-y += $(obj)/pgtable_64.o
  84 endif
  85
  86 $(obj)/eboot.o: KBUILD_CFLAGS += -fshort-wchar -mno-red-zone
  87
  88 vmlinux-objs-$(CONFIG_EFI_STUB) += $(obj)/eboot.o $(obj)/efi_stub_$(BITS).o \
  89         $(objtree)/drivers/firmware/efi/libstub/lib.a
  90 vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_thunk_$(BITS).o
  91
  92 # The compressed kernel is built with -fPIC/-fPIE so that a boot loader
  93 # can place it anywhere in memory and it will still run. However, since
  94 # it is executed as-is without any ELF relocation processing performed
  95 # (and has already had all relocation sections stripped from the binary),
  96 # none of the code can use data relocations (e.g. static assignments of
  97 # pointer values), since they will be meaningless at runtime. This check
  98 # will refuse to link the vmlinux if any of these relocations are found.
  99 quiet_cmd_check_data_rel = DATAREL $@
 100 define cmd_check_data_rel
 101         for obj in $(filter %.o,$^); do \
 102                 ${CROSS_COMPILE}readelf -S $$obj | grep -qF .rel.local && { \
 103                         echo "error: $$obj has data relocations!" >&2; \
 104                         exit 1; \
 105                 } || true; \
 106         done
 107 endef
 108
 109 # We need to run two commands under "if_changed", so merge them into a
 110 # single invocation.
 111 quiet_cmd_check-and-link-vmlinux = LD      $@
 112       cmd_check-and-link-vmlinux = $(cmd_check_data_rel); $(cmd_ld)
 113
 114 $(obj)/vmlinux: $(vmlinux-objs-y) FORCE
 115         $(call if_changed,check-and-link-vmlinux)
 116
 117 OBJCOPYFLAGS_vmlinux.bin :=  -R .comment -S
 118 $(obj)/vmlinux.bin: vmlinux FORCE
 119         $(call if_changed,objcopy)
 120
 121 targets += $(patsubst $(obj)/%,%,$(vmlinux-objs-y)) vmlinux.bin.all vmlinux.relocs
 122
 123 CMD_RELOCS = arch/x86/tools/relocs
 124 quiet_cmd_relocs = RELOCS  $@
 125       cmd_relocs = $(CMD_RELOCS) $< > $@;$(CMD_RELOCS) --abs-relocs $<
 126 $(obj)/vmlinux.relocs: vmlinux FORCE
 127         $(call if_changed,relocs)
 128
 129 vmlinux.bin.all-y := $(obj)/vmlinux.bin
 130 vmlinux.bin.all-$(CONFIG_X86_NEED_RELOCS) += $(obj)/vmlinux.relocs
 131
 132 $(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE
 133         $(call if_changed,gzip)
 134 $(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y) FORCE
 135         $(call if_changed,bzip2)
 136 $(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y) FORCE
 137         $(call if_changed,lzma)
 138 $(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y) FORCE
 139         $(call if_changed,xzkern)
 140 $(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y) FORCE
 141         $(call if_changed,lzo)
 142 $(obj)/vmlinux.bin.lz4: $(vmlinux.bin.all-y) FORCE
 143         $(call if_changed,lz4)
 144
 145 suffix-$(CONFIG_KERNEL_GZIP)    := gz
 146 suffix-$(CONFIG_KERNEL_BZIP2)   := bz2
 147 suffix-$(CONFIG_KERNEL_LZMA)    := lzma
 148 suffix-$(CONFIG_KERNEL_XZ)      := xz
 149 suffix-$(CONFIG_KERNEL_LZO)     := lzo
 150 suffix-$(CONFIG_KERNEL_LZ4)     := lz4
 151
 152 quiet_cmd_mkpiggy = MKPIGGY $@
 153       cmd_mkpiggy = $(obj)/mkpiggy $< > $@ || ( rm -f $@ ; false )
 154
 155 targets += piggy.S
 156 $(obj)/piggy.S: $(obj)/vmlinux.bin.$(suffix-y) $(obj)/mkpiggy FORCE
 157         $(call if_changed,mkpiggy)