1# 2# linux/arch/x86/boot/compressed/Makefile 3# 4# create a compressed vmlinux image from the original vmlinux 5# 6# vmlinuz is: 7# decompression code (*.o) 8# asm globals (piggy.S), including: 9# vmlinux.bin.(gz|bz2|lzma|...) 10# 11# vmlinux.bin is: 12# vmlinux stripped of debugging and comments 13# vmlinux.bin.all is: 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 18 19KASAN_SANITIZE := n 20OBJECT_FILES_NON_STANDARD := y 21 22# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in. 23KCOV_INSTRUMENT := n 24 25targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \ 26 vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4 27 28KBUILD_CFLAGS := -m$(BITS) -D__KERNEL__ $(LINUX_INCLUDE) -O2 29KBUILD_CFLAGS += -fno-strict-aliasing $(call cc-option, -fPIE, -fPIC) 30KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING 31cflags-$(CONFIG_X86_32) := -march=i386 32cflags-$(CONFIG_X86_64) := -mcmodel=small 33KBUILD_CFLAGS += $(cflags-y) 34KBUILD_CFLAGS += -mno-mmx -mno-sse 35KBUILD_CFLAGS += $(call cc-option,-ffreestanding) 36KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) 37 38KBUILD_AFLAGS := $(KBUILD_CFLAGS) -D__ASSEMBLY__ 39GCOV_PROFILE := n 40UBSAN_SANITIZE :=n 41 42LDFLAGS := -m elf_$(UTS_MACHINE) 43ifeq ($(CONFIG_RELOCATABLE),y) 44# If kernel is relocatable, build compressed kernel as PIE. 45ifeq ($(CONFIG_X86_32),y) 46LDFLAGS += $(call ld-option, -pie) $(call ld-option, --no-dynamic-linker) 47else 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. 51LDFLAGS += $(shell $(LD) --help 2>&1 | grep -q "\-z noreloc-overflow" \ 52 && echo "-z noreloc-overflow -pie --no-dynamic-linker") 53endif 54endif 55LDFLAGS_vmlinux := -T 56 57hostprogs-y := mkpiggy 58HOST_EXTRACFLAGS += -I$(srctree)/tools/include 59 60sed-voffset := -e 's/^\([0-9a-fA-F]*\) [ABCDGRSTVW] \(_text\|__bss_start\|_end\)$$/\#define VO_\2 _AC(0x\1,UL)/p' 61 62quiet_cmd_voffset = VOFFSET $@ 63 cmd_voffset = $(NM) $< | sed -n $(sed-voffset) > $@ 64 65targets += ../voffset.h 66 67$(obj)/../voffset.h: vmlinux FORCE 68 $(call if_changed,voffset) 69 70$(obj)/misc.o: $(obj)/../voffset.h 71 72vmlinux-objs-y := $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \ 73 $(obj)/string.o $(obj)/cmdline.o $(obj)/error.o \ 74 $(obj)/piggy.o $(obj)/cpuflags.o 75 76vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o 77vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o 78ifdef CONFIG_X86_64 79 vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/pagetable.o 80endif 81 82$(obj)/eboot.o: KBUILD_CFLAGS += -fshort-wchar -mno-red-zone 83 84vmlinux-objs-$(CONFIG_EFI_STUB) += $(obj)/eboot.o $(obj)/efi_stub_$(BITS).o \ 85 $(objtree)/drivers/firmware/efi/libstub/lib.a 86vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_thunk_$(BITS).o 87 88# The compressed kernel is built with -fPIC/-fPIE so that a boot loader 89# can place it anywhere in memory and it will still run. However, since 90# it is executed as-is without any ELF relocation processing performed 91# (and has already had all relocation sections stripped from the binary), 92# none of the code can use data relocations (e.g. static assignments of 93# pointer values), since they will be meaningless at runtime. This check 94# will refuse to link the vmlinux if any of these relocations are found. 95quiet_cmd_check_data_rel = DATAREL $@ 96define cmd_check_data_rel 97 for obj in $(filter %.o,$^); do \ 98 readelf -S $$obj | grep -qF .rel.local && { \ 99 echo "error: $$obj has data relocations!" >&2; \ 100 exit 1; \ 101 } || true; \ 102 done 103endef 104 105$(obj)/vmlinux: $(vmlinux-objs-y) FORCE 106 $(call if_changed,check_data_rel) 107 $(call if_changed,ld) 108 109OBJCOPYFLAGS_vmlinux.bin := -R .comment -S 110$(obj)/vmlinux.bin: vmlinux FORCE 111 $(call if_changed,objcopy) 112 113targets += $(patsubst $(obj)/%,%,$(vmlinux-objs-y)) vmlinux.bin.all vmlinux.relocs 114 115CMD_RELOCS = arch/x86/tools/relocs 116quiet_cmd_relocs = RELOCS $@ 117 cmd_relocs = $(CMD_RELOCS) $< > $@;$(CMD_RELOCS) --abs-relocs $< 118$(obj)/vmlinux.relocs: vmlinux FORCE 119 $(call if_changed,relocs) 120 121vmlinux.bin.all-y := $(obj)/vmlinux.bin 122vmlinux.bin.all-$(CONFIG_X86_NEED_RELOCS) += $(obj)/vmlinux.relocs 123 124$(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE 125 $(call if_changed,gzip) 126$(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y) FORCE 127 $(call if_changed,bzip2) 128$(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y) FORCE 129 $(call if_changed,lzma) 130$(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y) FORCE 131 $(call if_changed,xzkern) 132$(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y) FORCE 133 $(call if_changed,lzo) 134$(obj)/vmlinux.bin.lz4: $(vmlinux.bin.all-y) FORCE 135 $(call if_changed,lz4) 136 137suffix-$(CONFIG_KERNEL_GZIP) := gz 138suffix-$(CONFIG_KERNEL_BZIP2) := bz2 139suffix-$(CONFIG_KERNEL_LZMA) := lzma 140suffix-$(CONFIG_KERNEL_XZ) := xz 141suffix-$(CONFIG_KERNEL_LZO) := lzo 142suffix-$(CONFIG_KERNEL_LZ4) := lz4 143 144quiet_cmd_mkpiggy = MKPIGGY $@ 145 cmd_mkpiggy = $(obj)/mkpiggy $< > $@ || ( rm -f $@ ; false ) 146 147targets += piggy.S 148$(obj)/piggy.S: $(obj)/vmlinux.bin.$(suffix-y) $(obj)/mkpiggy FORCE 149 $(call if_changed,mkpiggy) 150