[PATCH mtd-utils] nandwrite: warn about writing 0xff blocks

[Richard Weinberger]

----- Ursprüngliche Mail -----
> Von: "Miquel Raynal" <miquel.raynal at bootlin.com>
>> > While I like the patch I'm still not so convinced why we can't make
>> > skipallffs=true by default.
>> 
>> I thought it's about changing / breaking user interface:
>> 
>> [2022-03-25] [11:40:53 CET] <derRichard> mraynal: i think we should make
>> --skip-all-ffs default in nandwrite
>> [2022-03-25] [11:40:56 CET] <derRichard> what do you think?
>> [2022-03-25] [11:42:00 CET] <rmilecki> i was preparing a patch with warning if
>> any 0xff block has been written
>> [2022-03-25] [11:42:33 CET] <rmilecki> i didn't know defaulting to
>> --skip-all-ffs can be done
>> [2022-03-25] [11:47:05 CET] <mraynal> well, that would break the user interface
> 
> Indeed I raised this issue but I am not opposed to this change if
> everybody agrees that it's a good move. In particular, the NAND
> sublayer will give the same "empty" data to userspace whether it
> programmed empty pages or skipped them. So I guess we are fine against
> direct regressions (but we might break clever scripts doing strange
> things).
> 
> I would go for this solution:
> - Bring support for the double flag -[no-]skip-ffs
> - Make the use of -skip-ffs the default
> So that it is easy for scripting people to ensure their way is fine?

Also emit a warning that a 0xff page is being skipped if the user
no not specify anything at the command line.
Then users will notice that the default has changed.

Thanks,
//richard