今天心血来潮，想编译以下Linux内核来玩玩。一开始编译x86的版本，遇到了openssl/opensslv.h文件缺失的问题，经过一番折腾，顺利解决（解决过程请参见“linux（ubuntu）编译linux内核提示openssl/opensslv.h文件缺失”）（http://www.linuxdiyf.com/linux/28051.html）。然后就进而想编译一个arm的版本出来，放到我的mini2440开发板上跑一跑。
于是按照文章（移植Linux3.4.2版本内核到mini2440）的步骤[附1]，修改makefile，指定交叉编译器（arm-linux-gcc）和配置文件（s3c2410_defconfig），运行make uImage命令。大约半个多小时后，提示：
CC arch/arm/boot/compressed/decompress.o
AS arch/arm/boot/compressed/debug.o
CC arch/arm/boot/compressed/string.o
SHIPPED arch/arm/boot/compressed/lib1funcs.S
AS arch/arm/boot/compressed/lib1funcs.o
SHIPPED arch/arm/boot/compressed/ashldi3.S
AS arch/arm/boot/compressed/ashldi3.o
SHIPPED arch/arm/boot/compressed/bswapsdi2.S
AS arch/arm/boot/compressed/bswapsdi2.o
LD arch/arm/boot/compressed/vmlinux
OBJCOPY arch/arm/boot/zImage
Kernel: arch/arm/boot/zImage is ready
UIMAGE arch/arm/boot/uImage
"mkimage" command not found - U-Boot images will not be built
make[1]: *** [arch/arm/boot/uImage] 错误 1
make: *** [uImage] 错误 2
搜索了一下，发现是因为系统缺少mkimage工具导致，解决办法很简单，直接安装一下这个工具就好：
leon@Ubuntu:~/linux$ sudo apt-get install uboot-mkimage
正在读取软件包列表... 完成
正在分析软件包的依赖关系树
正在读取状态信息... 完成
将会安装下列额外的软件包：
u-boot-tools
下列【新】软件包将被安装：
u-boot-tools uboot-mkimage
升级了 0 个软件包，新安装了 2 个软件包，要卸载 0 个软件包，有 221 个软件包未被升级。
需要下载 71.4 kB 的软件包。
解压缩后会消耗掉 245 kB 的额外空间。
您希望继续执行吗？[Y/n]y
获取：1 http://cn.archive.ubuntu.com/ubuntu/ precise/main u-boot-tools amd64 2011.09-2 [60.4 kB]
获取：2 http://cn.archive.ubuntu.com/ubuntu/ precise/main uboot-mkimage all 2011.09-2 [11.0 kB]
下载 71.4 kB，耗时 0秒 (201 kB/s)
Selecting previously unselected package u-boot-tools.
(正在读取数据库 ... 系统当前共安装有 166411 个文件和目录。)
正在解压缩 u-boot-tools (从 .../u-boot-tools_2011.09-2_amd64.deb) ...
Selecting previously unselected package uboot-mkimage.
正在解压缩 uboot-mkimage (从 .../uboot-mkimage_2011.09-2_all.deb) ...
正在处理用于 man-db 的触发器...
正在设置 u-boot-tools (2011.09-2) ...
正在设置 uboot-mkimage (2011.09-2) ..
然后再次运行生成命令，顺利成功！
leon@Ubuntu:~/linux$ make uImage
CHK include/config/kernel.release
CHK include/generated/uapi/linux/version.h
CHK include/generated/utsrelease.h
CHK include/generated/bounds.h
CHK include/generated/timeconst.h
CHK include/generated/asm-offsets.h
CALL scripts/checksyscalls.sh
CHK include/generated/compile.h
Kernel: arch/arm/boot/Image is ready
Kernel: arch/arm/boot/zImage is ready
UIMAGE arch/arm/boot/uImage
Image Name: Linux-4.9.0-dirty
Created: Tue Jan 24 16:25:24 2017
Image Type: ARM Linux Kernel Image (uncompressed)
Data Size: 3200648 Bytes = 3125.63 kB = 3.05 MB
Load Address: 30108000
Entry Point: 30108000
生成的可执行文件信息如下：
leon@Ubuntu:~/linux/arch/arm/boot$ file uImage
uImage: u-boot legacy uImage, Linux-4.9.0-dirty, Linux/ARM, OS Kernel Image (Not compressed), 3200648 bytes, Tue Jan 24 16:25:24 2017, Load Address: 0x30108000, Entry Point: 0x30108000, Header CRC: 0xE1FE38F1, Data CRC: 0x5E772F78
搞定！收工！
附[1]：
