[Yaffs] mount problem with yaffs bug: fs/yaffs2/yaffs_guts.c…

Hi, friends:
I find some problema about u/mount.
Here is my test:

First, I erase the nand and mount the partition,
When I copy some mp3 file to the partition, then umount it.
After reboot, mounting the partition works fine.

If I do not do umount command, the other steps are the same.
Mounting will pop lots of yaffs bugs.

my friends, any suggests for me?

Thanks in advanced.

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/ # mount -t yaffs /dev/mtdblock/0 /mnt/f0
yaffs: dev is 32505856 name is "mtdblock0"
yaffs: Attempting MTD mount on 31.0, "mtdblock0"
yaffs: auto selecting yaffs2
**>> yaffs: BlockBits block 27375 is not valid
==>> yaffs bug: fs/yaffs2/yaffs_guts.c 343
**>> yaffs: Chunk Id (27375:111) invalid
==>> yaffs bug: fs/yaffs2/yaffs_guts.c 355
**>> yaffs: getBlockInfo block 27375 is not valid
==>> yaffs bug: fs/yaffs2/yaffs_getblockinfo.h 29
**>> yaffs: BlockBits block 27375 is not valid
==>> yaffs bug: fs/yaffs2/yaffs_guts.c 343
**>> yaffs: Chunk Id (27375:111) invalid
==>> yaffs bug: fs/yaffs2/yaffs_guts.c 355
**>> yaffs: BlockBits block 25336 is not valid
==>> yaffs bug: fs/yaffs2/yaffs_guts.c 343
**>> yaffs: Chunk Id (25336:120) invalid
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