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Date: Sat, 26 Mar 2016 07:01:37 +0100
From: Willy Tarreau <w@1wt.eu>
To: Richard Weinberger <richard@nod.at>
Cc: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>,
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Subject: Re: ubiblock RW
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On Fri, Mar 25, 2016 at 10:25:17PM +0100, Richard Weinberger wrote:
> Am 25.03.2016 um 21:50 schrieb Ezequiel Garcia:
> > I guess we could have some UBI parameter to enable this support,
> > and print a very noisy message to warn users about potential
> > device wear out -- naively assuming users read messages...
> 
> As I wrote in my previous mail, I think a new parameter for the ubiblock
> tool would do the job.
> I'd default ubiblock to RO and via the ubiblock tool you can enable RW mode.
> ...which would also trigger a warning.
> 
> What I'd like to avoid is a kernel command line or a Kconfig option to make
> RW default. If someone *really* wants RW she has to run ubiblock --enable-rw....
> in userspace. This should even work for block filesystems on top of UBI
> as root fs as you can remount them later RW.
> 
> Sounds like a plan?

I would see something a little bit better (from a user perspective), though
I don't know if it's possible. It would be nice to mark the UBI image RO/RW
when it is created via ubiformat. That would be a bit stored on the ubiblock
itself. That way the decision is taken at creation time and is not changed
later (or only using a specific tool). Note that it is very possible I'm
missing something important, but you get the idea.

Thanks,
Willy