mkfs.jffs2 min erase block size: 4 vs 8 KiB

[Guillaume LECERF]

Hi Mike,

2011/6/22 Mike Frysinger <vapier.adi at gmail.com>:
> the current mkfs.jffs2 util has in its --eraseblock handling:
> /* If it's less than 8KiB, they're not allowed */
> if (erase_block_size < 0x2000) {
>    fprintf(stderr, "Erase size 0x%x too small. Increasing to 8KiB minimum\n",
>        erase_block_size);
>    erase_block_size = 0x2000;
> }
>
> but i cant seem to find documentation on where this comes from.  it's
> not uncommon to have SPI flashes with 4KiB erase sectors, and removing
> this sanity check and allowing 4 KiB seems to produce an image that
> works OK.
>
> am i missing something ?  or should i send a patch to drop this check ?

This has already be pointed by Fabio Giovagnini :
http://lists.infradead.org/pipermail/linux-mtd/2011-February/033992.html
He patched mkfs.jffs2 to allow "--eraseblock=0x1000" and he reported
it works ok.

AFAIK, there should be no problem removing this sanity check.
Artem, david, objections ?

-- 
Guillaume LECERF
GeeXboX developer - www.geexbox.org