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 KBUILD_CFLAGS += -Wno-pointer-sign
  41
  42 KBUILD_AFLAGS  := $(KBUILD_CFLAGS) -D__ASSEMBLY__
  43 GCOV_PROFILE := n
  44 UBSAN_SANITIZE :=n
  45
  46 KBUILD_LDFLAGS := -m elf_$(UTS_MACHINE)
  47 # Compressed kernel should be built as PIE since it may be loaded at any
  48 # address by the bootloader.
  49 ifeq ($(CONFIG_X86_32),y)
  50 KBUILD_LDFLAGS += $(call ld-option, -pie) $(call ld-option, --no-dynamic-linker)
  51 else
  52 # To build 64-bit compressed kernel as PIE, we disable relocation
  53 # overflow check to avoid relocation overflow error with a new linker
  54 # command-line option, -z noreloc-overflow.
  55 KBUILD_LDFLAGS += $(shell $(LD) --help 2>&1 | grep -q "\-z noreloc-overflow" \
  56         && echo "-z noreloc-overflow -pie --no-dynamic-linker")
  57 endif
  58 LDFLAGS_vmlinux := -T
  59
  60 hostprogs-y     := mkpiggy
  61 HOST_EXTRACFLAGS += -I$(srctree)/tools/include
  62
  63 sed-voffset := -e 's/^\([0-9a-fA-F]*\) [ABCDGRSTVW] \(_text\|__bss_start\|_end\)$$/\#define VO_\2 _AC(0x\1,UL)/p'
  64
  65 quiet_cmd_voffset = VOFFSET $@
  66       cmd_voffset = $(NM) $< | sed -n $(sed-voffset) > $@
  67
  68 targets += ../voffset.h
  69
  70 $(obj)/../voffset.h: vmlinux FORCE
  71         $(call if_changed,voffset)
  72
  73 $(obj)/misc.o: $(obj)/../voffset.h
  74
  75 vmlinux-objs-y := $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \
  76         $(obj)/string.o $(obj)/cmdline.o $(obj)/error.o \
  77         $(obj)/piggy.o $(obj)/cpuflags.o
  78
  79 vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o
  80 vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o
  81 ifdef CONFIG_X86_64
  82         vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr_64.o
  83         vmlinux-objs-y += $(obj)/mem_encrypt.o
  84         vmlinux-objs-y += $(obj)/pgtable_64.o
  85 endif
  86
  87 $(obj)/eboot.o: KBUILD_CFLAGS += -fshort-wchar -mno-red-zone
  88
  89 vmlinux-objs-$(CONFIG_EFI_STUB) += $(obj)/eboot.o $(obj)/efi_stub_$(BITS).o \
  90         $(objtree)/drivers/firmware/efi/libstub/lib.a
  91 vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_thunk_$(BITS).o
  92
  93 # The compressed kernel is built with -fPIC/-fPIE so that a boot loader
  94 # can place it anywhere in memory and it will still run. However, since
  95 # it is executed as-is without any ELF relocation processing performed
  96 # (and has already had all relocation sections stripped from the binary),
  97 # none of the code can use data relocations (e.g. static assignments of
  98 # pointer values), since they will be meaningless at runtime. This check
  99 # will refuse to link the vmlinux if any of these relocations are found.
 100 quiet_cmd_check_data_rel = DATAREL $@
 101 define cmd_check_data_rel
 102         for obj in $(filter %.o,$^); do \
 103                 ${CROSS_COMPILE}readelf -S $$obj | grep -qF .rel.local && { \
 104                         echo "error: $$obj has data relocations!" >&2; \
 105                         exit 1; \
 106                 } || true; \
 107         done
 108 endef
 109
 110 # We need to run two commands under "if_changed", so merge them into a
 111 # single invocation.
 112 quiet_cmd_check-and-link-vmlinux = LD      $@
 113       cmd_check-and-link-vmlinux = $(cmd_check_data_rel); $(cmd_ld)
 114
 115 $(obj)/vmlinux: $(vmlinux-objs-y) FORCE
 116         $(call if_changed,check-and-link-vmlinux)
 117
 118 OBJCOPYFLAGS_vmlinux.bin :=  -R .comment -S
 119 $(obj)/vmlinux.bin: vmlinux FORCE
 120         $(call if_changed,objcopy)
 121
 122 targets += $(patsubst $(obj)/%,%,$(vmlinux-objs-y)) vmlinux.bin.all vmlinux.relocs
 123
 124 CMD_RELOCS = arch/x86/tools/relocs
 125 quiet_cmd_relocs = RELOCS  $@
 126       cmd_relocs = $(CMD_RELOCS) $< > $@;$(CMD_RELOCS) --abs-relocs $<
 127 $(obj)/vmlinux.relocs: vmlinux FORCE
 128         $(call if_changed,relocs)
 129
 130 vmlinux.bin.all-y := $(obj)/vmlinux.bin
 131 vmlinux.bin.all-$(CONFIG_X86_NEED_RELOCS) += $(obj)/vmlinux.relocs
 132
 133 $(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE
 134         $(call if_changed,gzip)
 135 $(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y) FORCE
 136         $(call if_changed,bzip2)
 137 $(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y) FORCE
 138         $(call if_changed,lzma)
 139 $(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y) FORCE
 140         $(call if_changed,xzkern)
 141 $(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y) FORCE
 142         $(call if_changed,lzo)
 143 $(obj)/vmlinux.bin.lz4: $(vmlinux.bin.all-y) FORCE
 144         $(call if_changed,lz4)
 145
 146 suffix-$(CONFIG_KERNEL_GZIP)    := gz
 147 suffix-$(CONFIG_KERNEL_BZIP2)   := bz2
 148 suffix-$(CONFIG_KERNEL_LZMA)    := lzma
 149 suffix-$(CONFIG_KERNEL_XZ)      := xz
 150 suffix-$(CONFIG_KERNEL_LZO)     := lzo
 151 suffix-$(CONFIG_KERNEL_LZ4)     := lz4
 152
 153 quiet_cmd_mkpiggy = MKPIGGY $@
 154       cmd_mkpiggy = $(obj)/mkpiggy $< > $@ || ( rm -f $@ ; false )
 155
 156 targets += piggy.S
 157 $(obj)/piggy.S: $(obj)/vmlinux.bin.$(suffix-y) $(obj)/mkpiggy FORCE
 158         $(call if_changed,mkpiggy)