移植linux到U盘时，启动遇到mount: could not find filesystem '/dev/root'

pengdingbo

移植linux到U盘时，启动遇到mount: could not find filesystem '/dev/root' [复制链接]

本人想把硬盘上的linux 2.6.28系统移植到U盘上，一个vmlinux 和 initrd.img在硬盘上运行良好。硬盘分了7个分区，sda1 是boot分区，sda2是根分区，一个2G的U盘，分了2个分区，都格式成ext3，sda1是boot分区，copy硬盘boot里的东西，打算把root挂在sda2上，U盘sda2也copy了硬盘的lib;etc;sbin;bin;dev;sysroot;proc;mnt;几个必需目录的内容；
grub是这样写的 :

default=1
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title USB(2.6.28)
   root (hd0,0)
   kernel /vmlinuz-2.6.28 ro root=/dev/sda2
   initrd /initrd-usb.img

启动后一直遇到这个错误：
mount: could not find filesystem '/dev/root'
Setting up other filesystems.
Setting up new root fs
setuproot: moving /dev failed: No such file or directory
no fstab.sys, mounting internal defaults
setuproot: error mounting /proc: No such file or directory
setuproot: error mounting /sys: No such file or directory
Switching to new root and running init.
unmounting old /dev
unmounting old /proc
unmounting old /sys
switchroot: mount failed: No such file or directory
Kernel panic - not syncing: Attempted to kill init!

提示找不到根文件系统

折腾几天，一直找不到原因，还望大虾赐教！！