linux 内核升级方法

 linux 内核升级方法

前沿：你是不是为你的x86下linux代码的内核版本和嵌入式编译的时候不一致而发愁，下面的过程主要是内核的编译和升级的步骤。

注：下面只贴代码，注意哪些带颜色的就是步骤中很重要的部分（下面代码在redhat中实验成功，在centos有些不同，不过后来也成功了（下面介绍的有））

1.redhat中的步骤

[root@localhost guoqian]# ls

linux-2.6.29  linux-2.6.29.tar.bz2

[root@localhost guoqian]# cd linux-2.6.29

[root@localhost linux-2.6.29]# cp /boot/config-2.6.18-53.el5 ./.config

[root@localhost linux-2.6.29]# ls -a

.        COPYING        firmware    ipc       MAINTAINERS  REPORTING-BUGS  usr

..       CREDITS        fs          Kbuild    Makefile     samples         virt

arch     crypto         .gitignore  kernel    mm           scripts

block    Documentation  include     lib       net          security

.config  drivers        init        .mailmap  README       sound

[root@localhost linux-2.6.29]# make menuconfig

  HOSTCC  scripts/basic/fixdep

  HOSTCC  scripts/basic/docproc


[root@localhost linux-2.6.29]# make bzImage

……..


  OBJCOPY arch/x86/boot/setup.bin

  OBJCOPY arch/x86/boot/vmlinux.bin

  HOSTCC  arch/x86/boot/tools/build

  BUILD   arch/x86/boot/bzImage

Kernel: arch/x86/boot/bzImage is ready  (#1)

[root@localhost linux-2.6.29]# make modules

....


root@localhost linux-2.6.29]# make modules_install


[root@localhost linux-2.6.29]# ls /lib/modules/

2.6.18-53.el5  2.6.29   （这个2.6.29出来了，这个是为下面做准备）

[root@localhost linux-2.6.29]# cd ..

[root@localhost guoqian]# ls

4-1-2  linux-2.6.29  linux-2.6.29.tar.bz2

[root@localhost guoqian]# mkinitrd initrd-2.6.29 2.6.29

[root@localhost guoqian]# ls

4-1-2  initrd-2.6.29  linux-2.6.29  linux-2.6.29.tar.bz2


[root@localhost guoqian]# cp initrd-2.6.29 /boot/

[root@localhost guoqian]# ls /boot

config-2.6.18-53.el5      initrd-2.6.29             System.map-2.6.18-53.el5

grub                      lost+found                vmlinuz-2.6.18-53.el5

initrd-2.6.18-53.el5.img  symvers-2.6.18-53.el5.gz

 [root@localhost guoqian]# cp ./linux-2.6.29/arch/x86/boot/bzImage  /boot/vmlinuz-2.6.29

(注：上面这个名字很重要，后面的那个2.6.29一定要和/lib/modules目录下的有才行)

[root@localhost guoqian]# ls /boot

config-2.6.18-53.el5      initrd-2.6.29             System.map-2.6.18-53.el5

grub                      lost+found                vmlinuz-2.6.18-53.el5

initrd-2.6.18-53.el5.img  symvers-2.6.18-53.el5.gz  vmlinuz-2.6.29



[root@localhost guoqian]# vi /etc/grub.conf

# grub.conf generated by anaconda

#

# Note that you do not have to rerun grub after making changes to this file

# NOTICE:  You have a /boot partition.  This means that

#          all kernel and initrd paths are relative to /boot/, eg.

#          root (hd0,1)

#          kernel /vmlinuz-version ro root=/dev/sda1

#          initrd /initrd-version.img

#boot=/dev/sda

default=0

timeout=7

splashimage=(hd0,1)/grub/splash.xpm.gz

hiddenmenu

title Red Hat Enterprise Linux Server (2.6.18-53.el5)

        root (hd0,1)

        kernel /vmlinuz-2.6.18-53.el5 ro root=LABEL=/ rhgb quiet

        initrd /initrd-2.6.18-53.el5.img


title My-Linux(2.6.29)

        root (hd0,1)

        kernel /vmlinuz-2.6.29 ro root=LABEL=/ rhgb quiet

        initrd /initrd-2.6.29



1.centos中的步骤

上面的是redhat中的设置，下面介绍一下centos中的设置：基本上所有的都一样，就是最后的哪一个配置文件有些不同，下面贴出来centos中的/etc/grub.conf中的内容：

# grub.conf generated by anaconda

#

# Note that you do not have to rerun grub after making changes to this file

# NOTICE:  You do not have a /boot partition.  This means that

#          all kernel and initrd paths are relative to /, eg.

#          root (hd0,0)

#          kernel /boot/vmlinuz-version ro root=/dev/sda1

#          initrd /boot/initrd-version.img

#boot=/dev/sda

default=0



timeout=5

splashimage=(hd0,0)/boot/grub/splash.xpm.gz

hiddenmenu

title CentOS (2.6.18-194.32.1.el5)

        root (hd0,0)

        kernel /boot/vmlinuz-2.6.18-194.32.1.el5 ro root=LABEL=/ apm=on  apm=powe-off rhgb quiet

        initrd /boot/initrd-2.6.18-194.32.1.el5.img

title CentOS (2.6.18-92.el5)

        root (hd0,0)

        kernel /boot/vmlinuz-2.6.18-92.el5 ro root=LABEL=/ apm=on  apm=powe-off rhgb quiet

        initrd /boot/initrd-2.6.18-92.el5.img



#下面的是我添加的

title my_linux(2.6.29)

        root(hd0,0)

        kernel /boot/vmlinuz-2.6.29 ro root=LABEL=/ apm=on  apm=powe-off rhgb quiet

        initrd /boot/initrd-2.6.29



/*看到了么，centos中就是比redhat中多了一个/boot(后来证明，这个/boot也不一定，你要看原来的设置，直接复制粘贴，修改，因为我发现centos有时候会变的)，

还有多了kernel中后面的那些内容。不过我还是有点郁闷，centos不是说是redhat的克隆版么？怎么会这个地方不一样？怎么解释。。。呵呵。。*/