hi3798cv200 nand烧写rootfs异常

在fastboot下使用nand write.yaffs没有问题
但是在linux下，使用sample里面的flash读写用例烧录rootfs，没有报错。
但是重启后，有时候是正常的，
但大部分情况下会丢失文件及目录，还有库文件
类似这样：
./sample_flash -W -D /dev/mtd9  -T nand -i rootfs_4k8b.yaffs  -O
./sample_flash: error while loading shared libraries: libhi_common.so: cannot open shared object file: No such file or directory
还有时候会出现???乱码：
# ls
bin
boot
dev
disk
home
kmod
lib
lib64
linuxrc
lost+found
obj748
opt
proc
sbin
share
tmp
var
?????????????????????????????????????????????????????
?????????????????????????????????????????????????????
?????????????????????????????????????????????????????

can't open /dev/tty2: No such file or directory
can't open /dev/tty3: No such file or directory
can't open /dev/tty4: No such file or directory
can't open /dev/tty2: No such file or directory
can't open /dev/tty3: No such file or directory
can't open /dev/tty4: No such file or directory
can't open /dev/tty2: No such file or directory
can't open /dev/tty3: No such file or directory

请问可能是什么问题，还没有任何报错提示