'ubi clone' from Live NAND.

[Bill Pringlemeir]

On Wed, 2013-03-06 at 15:08 -0500, Bill Pringlemeir wrote:
>> I have a 'ubinize' image that I have created on a PC and I have a
>> 'raw' copy of the NAND flash on a 'Live' Linux distribution; the
>> target was cleanly unmounted.  I use nandsim, with all my real FLASH
>> id bytes and setup partitions as per the target.  Here is the
>> sequence I follow on my PC.

>>  modprobe nandsim first_id_byte=0x2c second_id_byte=0xda third_id_byte=0x90 fourth_id_byte=0x95 parts=2,64,64
>>  flash_erase /dev/mtd3 0 0
>>  ubiformat /dev/mtd3 -f rootfs.ubi
>>  modprobe ubi mtd=3
>>  mount -t ubifs /dev/ubi0_3 /mnt/ubifs

On 13 Mar 2013, dedekind1 at gmail.com wrote:

> Does it work if you do the same, but avoid flashing your 'rootfs.ubi'.
> Just run 'ubiformat /dev/mtd3'. Can you mount it then, successfully do
> the I/O, unmount, and remount? If that works fine, you probably did
> not create 'rootfs.ubi' correctly. Double-check that you specified
> correct eraseblock size, correct nand page size and subpage size.

Thanks, all.  Indeed everything is fine if I don't use the 'improper'
rootfs.ubi.  Pekon Gupta had clued me in to the problem; If he hadn't, I
think Brian would have.  I am not using 'nandump' as I don't want the
file system to be live.  I wanted to use a flash programmer/JTAG device
to get a copy of the flash.

The problem is simply that the binary copy must include the 'entire
flash' and not be limited to a 'df' size because of course UBI does wear
leveling across the whole partition; a benefit of using it that I had
forgot about.

The 'dmesg' was basically as if someone suddenly truncated the 'UbiFs'
file system.

Sorry to trouble you.  I hope the information is useful to someone in
the future.  Btw, it doesn't seem that I have to avoid bad blocks.  I
think the 'host' UBI/UbiFs recognizes that erase blocks are bad from the
'target' copy and doesn't use them, or I was lucky and somehow I didn't
have bad blocks or the tool/code I am using is somehow removing them.

Regards,
Bill Pringlemeir.

-- 
If it weren't for pickpockets I'd have no sex life at all. 
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