[Yaffs] yaffs2 mount problem

Hi
I am using linux 2.6.11 kernel on an ARM board which has 128MiB of ST
Nand flash.

I used JFFS2 as a root file system and it works fine. Now I want to try
YAFFS2. I copied latest Yaffs2 source files into the kernel and
enabled yaffs2 and rebuild the kernel.

my  NAND partition is shown below.
dev:    size   erasesize  name
mtd0: 00200000 00020000 "M1 boot partition"
mtd1: 00200000 00020000 "Linux boot partition"
mtd2: 02800000 00020000 "Filesystem partition 1"
mtd3: 02800000 00020000 "Filesystem partition 2"
mtd4: 02c00000 00020000 "Free data section"

what I do step by step:

flash_eraseall /dev/mtd3
cd /mnt
mount -t jffs2 /dev/mtdblock3 test/

it mounts ok.
cd test
tar xzvf /root/rootfs.tar.gz

then I can see all directories of the file system in this directory like
/bin, /etc, /usr ....

cd /mnt
umount

if I mount again, then there is only lost+found in the /mnt/test
directory. would you tell me what went wrong?

If everthing was fine then I would reset the system and give the
following boot arguments to u-boot

root=/dev/mtdblock3 rw rootfstype=yaffs2

then I would expect system booting with yaffs2 as root fs.

best regards.

Ensar