grub-install --boot-directory=/mnt/boot /dev/sda

unrecognized option   --boot-directory=/mnt/boot 

Error 8r :Kernel must be loaded before booting

Switching to locksource tsc

registered taskstats version 1

input imps/2 Generic Wheel Mouse as /devices/platform/i802/serio1/input/

input3/ftc_cm-s 00:04 setting system clock to 

if you do not use raid use raid =noautodetect

Autodectection RAID arrays

Scanned 0 and added 0 device 

autorun

VFS can not open root device "null or unknown 253.0

please append a correct root= boot option here are the available partition

1确认文件系统的格式

内核是否支持这种文件系统格式