我们将上面的部分内容抓取出来，独立来分析，这样就不会被其它的代码干扰到，见下面的代码：
$(obj)/Image: vmlinux FORCE
$(call if_changed,objcopy)
@echo ' Kernel: $@ is ready'
$(call if_changed,objcopy)
@echo ' Kernel: $@ is ready'
由此可见，zImage是由arch/arm/boot/compressed/vmlinux二进制化得到的，与此同时在arch/armboot/compressed/Makefile中：
$(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/$(HEAD) $(obj)/piggy.$(suffix_y).o \
$(addprefix $(obj)/, $(OBJS)) $(lib1funcs) FORCE
$(call if_changed,ld)
@:
$(obj)/piggy.$(suffix_y): $(obj)/../Image FORCE
$(call if_changed,$(suffix_y))
$(obj)/piggy.$(suffix_y).o: $(obj)/piggy.$(suffix_y) FORCE
其中Image是由内核顶层目录下的vmlinux二进制化后得到的[见上面蓝色加粗部分代码]，其中在arch/armboot/compressed/Makefile链接选项中有个 –fpic参数：
EXTRA_CFLAGS := -fpic -fno-builtin
EXTRA_AFLAGS := -Wa,-march=all
总结一下zImage的组成，它是由一个压缩后的内核piggy.o，连接上一段初始化及解压功能的代码（head.o misc.o）,组成的。见下面的代码：
[plain]
# # linux/arch/arm/boot/compressed/Makefile # # create a compressed vmlinuz image from the original vmlinux # ...................... ...................... # # We now have a PIC decompressor implementation. Decompressors running # from RAM should not define ZTEXTADDR. Decompressors running directly # from ROM or Flash must define ZTEXTADDR (preferably via the config) # FIXME: Previous assignment to ztextaddr-y is lost here. See SHARK ifeq ($(CONFIG_ZBOOT_ROM),y) ZTEXTADDR := $(CONFIG_ZBOOT_ROM_TEXT) ZBSSADDR := $(CONFIG_ZBOOT_ROM_BSS) else ZTEXTADDR := 0 ZBSSADDR := ALIGN(8) endif SEDFLAGS = s/TEXT_START/$(ZTEXTADDR)/;s/BSS_START/$(ZBSSADDR)/ suffix_$(CONFIG_KERNEL_GZIP) = gzip suffix_$(CONFIG_KERNEL_LZO) = lzo suffix_$(CONFIG_KERNEL_LZMA) = lzma targets := vmlinux vmlinux.lds \ piggy.$(suffix_y) piggy.$(suffix_y).o \ font.o font.c head.o misc.o $(OBJS) # Make sure files are removed during clean extra-y += piggy.gzip piggy.lzo piggy.lzma lib1funcs.S targets := vmlinux vmlinux.lds \piggy.$(suffix_y) piggy.$(suffix_y).o \
font.o font.c head.o misc.o $(OBJS)