suddently, can't use "cp jffs2.img /dev/mtd0" anymore

[rolf liu]

Yesterday, I can use "cp jffs2.img  /dev/mtd0" to copy the jffs2 image
to mtd. Today, I applied the cvs snapshot of mtd to kernel and
compiled it. Suddenly, the "cp" command stops working.

it tells me:
MTD do_write_buffer(): software timeout
cp: writing '/dev/mtd0' : Input/output error

any idea?

thanks