JFFS2 ECC options

[Davide CASCONE]

I'm working with JFFS2 on a NAND device. In order to disable the software ECC is it enough to set the mtd field "nand.eccmode" to "NAND_ECC_NONE"? 
If I do this, I have some CRC errors if JFFS2 file system includes a bad block. Is it right? Does the CRC check depend on the ECC options?

In order to use the summary support, is it enough to set the macro "CONFIG_JFFS2_SUMMARY" in the file ".config"? Do I have to re-make the file system image (that I create using the mkfs.jffs2 utility) in order to use it with the summary support?

Thanks in advance,
Davide