1 files changed, 160 insertions, 0 deletions
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
new file mode 100644
index 000000000..5642f025b
--- /dev/null
+++ b/arch/x86/boot/compressed/Makefile
@@ -0,0 +1,160 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# linux/arch/x86/boot/compressed/Makefile
+#
+# create a compressed vmlinux image from the original vmlinux
+#
+# vmlinuz is:
+#	decompression code (*.o)
+#	asm globals (piggy.S), including:
+#		vmlinux.bin.(gz|bz2|lzma|...)
+#
+# vmlinux.bin is:
+#	vmlinux stripped of debugging and comments
+# vmlinux.bin.all is:
+#	vmlinux.bin + vmlinux.relocs
+# vmlinux.bin.(gz|bz2|lzma|...) is:
+#	(see scripts/Makefile.lib size_append)
+#	compressed vmlinux.bin.all + u32 size of vmlinux.bin.all
+
+KASAN_SANITIZE			:= n
+OBJECT_FILES_NON_STANDARD	:= y
+
+# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
+KCOV_INSTRUMENT		:= n
+
+targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
+	vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4
+
+KBUILD_CFLAGS := -m$(BITS) -O2
+KBUILD_CFLAGS += -fno-strict-aliasing $(call cc-option, -fPIE, -fPIC)
+KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING
+cflags-$(CONFIG_X86_32) := -march=i386
+cflags-$(CONFIG_X86_64) := -mcmodel=small
+KBUILD_CFLAGS += $(cflags-y)
+KBUILD_CFLAGS += -mno-mmx -mno-sse
+KBUILD_CFLAGS += $(call cc-option,-ffreestanding)
+KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector)
+KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
+KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
+KBUILD_CFLAGS += -Wno-pointer-sign
+# Disable relocation relaxation in case the link is not PIE.
+KBUILD_CFLAGS += $(call as-option,-Wa$(comma)-mrelax-relocations=no)
+
+KBUILD_AFLAGS  := $(KBUILD_CFLAGS) -D__ASSEMBLY__
+GCOV_PROFILE := n
+UBSAN_SANITIZE :=n
+
+KBUILD_LDFLAGS := -m elf_$(UTS_MACHINE)
+# Compressed kernel should be built as PIE since it may be loaded at any
+# address by the bootloader.
+ifeq ($(CONFIG_X86_32),y)
+KBUILD_LDFLAGS += $(call ld-option, -pie) $(call ld-option, --no-dynamic-linker)
+else
+# To build 64-bit compressed kernel as PIE, we disable relocation
+# overflow check to avoid relocation overflow error with a new linker
+# command-line option, -z noreloc-overflow.
+KBUILD_LDFLAGS += $(shell $(LD) --help 2>&1 | grep -q "\-z noreloc-overflow" \
+	&& echo "-z noreloc-overflow -pie --no-dynamic-linker")
+endif
+LDFLAGS_vmlinux := -T
+
+hostprogs-y	:= mkpiggy
+HOST_EXTRACFLAGS += -I$(srctree)/tools/include
+
+sed-voffset := -e 's/^\([0-9a-fA-F]*\) [ABCDGRSTVW] \(_text\|__bss_start\|_end\)$$/\#define VO_\2 _AC(0x\1,UL)/p'
+
+quiet_cmd_voffset = VOFFSET $@
+      cmd_voffset = $(NM) $< | sed -n $(sed-voffset) > $@
+
+targets += ../voffset.h
+
+$(obj)/../voffset.h: vmlinux FORCE
+	$(call if_changed,voffset)
+
+$(obj)/misc.o: $(obj)/../voffset.h
+
+vmlinux-objs-y := $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \
+	$(obj)/string.o $(obj)/cmdline.o $(obj)/error.o \
+	$(obj)/piggy.o $(obj)/cpuflags.o
+
+vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o
+vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o
+ifdef CONFIG_X86_64
+	vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr_64.o
+	vmlinux-objs-y += $(obj)/mem_encrypt.o
+	vmlinux-objs-y += $(obj)/pgtable_64.o
+endif
+
+$(obj)/eboot.o: KBUILD_CFLAGS += -fshort-wchar -mno-red-zone
+
+vmlinux-objs-$(CONFIG_EFI_STUB) += $(obj)/eboot.o $(obj)/efi_stub_$(BITS).o \
+	$(objtree)/drivers/firmware/efi/libstub/lib.a
+vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_thunk_$(BITS).o
+
+# The compressed kernel is built with -fPIC/-fPIE so that a boot loader
+# can place it anywhere in memory and it will still run. However, since
+# it is executed as-is without any ELF relocation processing performed
+# (and has already had all relocation sections stripped from the binary),
+# none of the code can use data relocations (e.g. static assignments of
+# pointer values), since they will be meaningless at runtime. This check
+# will refuse to link the vmlinux if any of these relocations are found.
+quiet_cmd_check_data_rel = DATAREL $@
+define cmd_check_data_rel
+	for obj in $(filter %.o,$^); do \
+		$(READELF) -S $$obj | grep -qF .rel.local && { \
+			echo "error: $$obj has data relocations!" >&2; \
+			exit 1; \
+		} || true; \
+	done
+endef
+
+# We need to run two commands under "if_changed", so merge them into a
+# single invocation.
+quiet_cmd_check-and-link-vmlinux = LD      $@
+      cmd_check-and-link-vmlinux = $(cmd_check_data_rel); $(cmd_ld)
+
+$(obj)/vmlinux: $(vmlinux-objs-y) FORCE
+	$(call if_changed,check-and-link-vmlinux)
+
+OBJCOPYFLAGS_vmlinux.bin :=  -R .comment -S
+$(obj)/vmlinux.bin: vmlinux FORCE
+	$(call if_changed,objcopy)
+
+targets += $(patsubst $(obj)/%,%,$(vmlinux-objs-y)) vmlinux.bin.all vmlinux.relocs
+
+CMD_RELOCS = arch/x86/tools/relocs
+quiet_cmd_relocs = RELOCS  $@
+      cmd_relocs = $(CMD_RELOCS) $< > $@;$(CMD_RELOCS) --abs-relocs $<
+$(obj)/vmlinux.relocs: vmlinux FORCE
+	$(call if_changed,relocs)
+
+vmlinux.bin.all-y := $(obj)/vmlinux.bin
+vmlinux.bin.all-$(CONFIG_X86_NEED_RELOCS) += $(obj)/vmlinux.relocs
+
+$(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE
+	$(call if_changed,gzip)
+$(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y) FORCE
+	$(call if_changed,bzip2)
+$(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y) FORCE
+	$(call if_changed,lzma)
+$(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y) FORCE
+	$(call if_changed,xzkern)
+$(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y) FORCE
+	$(call if_changed,lzo)
+$(obj)/vmlinux.bin.lz4: $(vmlinux.bin.all-y) FORCE
+	$(call if_changed,lz4)
+
+suffix-$(CONFIG_KERNEL_GZIP)	:= gz
+suffix-$(CONFIG_KERNEL_BZIP2)	:= bz2
+suffix-$(CONFIG_KERNEL_LZMA)	:= lzma
+suffix-$(CONFIG_KERNEL_XZ)	:= xz
+suffix-$(CONFIG_KERNEL_LZO) 	:= lzo
+suffix-$(CONFIG_KERNEL_LZ4) 	:= lz4
+
+quiet_cmd_mkpiggy = MKPIGGY $@
+      cmd_mkpiggy = $(obj)/mkpiggy $< > $@ || ( rm -f $@ ; false )
+
+targets += piggy.S
+$(obj)/piggy.S: $(obj)/vmlinux.bin.$(suffix-y) $(obj)/mkpiggy FORCE
+	$(call if_changed,mkpiggy)