[Yaffs] Yaffs2 generate many badblocks

Hello all,

I am using yaffs2-7862c13 on a Linux 3.3 kernel on ARM (omap4).
When writing to the yaffs2 partition I could never write more than
approximatively half the size of the partition after the partition looks
like full.

Then if I try to erase the partition with flash_erase I have many
(approx. half of the partition) badblocks that I could never revert.

I have tried exactly the same manipulation on the same hardware with the
same kernel (but with a new flash) using jffs2 instead of yaffs2 and I
have not this problems of badblocks.

The flash is a 1Gb with 2048 bytes blocks.

Do you have any idea why ?
How could I revert the badblocks markers ?

Thanks for your help.

Patrick