While doing a kernel backup of an mtd (Memory Technology Device) from /dev/mtd/mtd3ro of a TI board gives many "BCH decoding failed", Here are system info

#cat /proc/mtd
dev:    size   erasesize  name
mtd0: 00080000 00020000 "X-Loader"
mtd1: 00140000 00020000 "U-Boot"
mtd2: 000c0000 00020000 "U-Boot Env"
mtd3: 00500000 00020000 "Kernel"
mtd4: 1f880000 00020000 "File System"

here is the method used,

dd  if=/dev/mtd/mtd3ro of=/data/local/tmp/mtd3.bin

doing a cat also returns the same error,

and here is the error,

BCH decoding failed
BCH decoding failed

yes, the destination has enough space ;)

tell me what do you think? Thanks