完整的错误信息如下：

zzh@ubuntu14:~/gem5/x86Dist/linux-2.6.28.4$ make menuconfig
 *** Unable to find the ncurses libraries or the
 *** required header files.
 *** 'make menuconfig' requires the ncurses libraries.
 *** 
 *** Install ncurses (ncurses-devel) and try again.
 *** 
make[1]: *** [scripts/kconfig/dochecklxdialog] Error 1
make: *** [menuconfig] Error 2

然后我就根据提示安装ncurses

zzh@ubuntu14:~/gem5/x86Dist/linux-2.6.28.4$ sudo apt-get install ncurses
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Package ncurses is not available,but is referred to by another package.
This may mean that the package is missing,has been obsoleted,or
is only available from another source

E: Package 'ncurses' has no installation candidate

试过apt-get update、apt-get upgrade等都没有解决问题，后来搜索了一圈，是要安装下面这个，才解决问题：

zzh@ubuntu14:~/gem5/x86Dist/linux-2.6.28.4$ sudo apt-get install libncurses5-dev

问题解决~~~这样就可以执行make menuconfig了