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Date: Thu, 1 Jun 2017 15:23:20 -0700
From: Brian Norris <computersforpeace@gmail.com>
To: Chris Packham <Chris.Packham@alliedtelesis.co.nz>
Cc: Boris Brezillon <boris.brezillon@free-electrons.com>,
 "dwmw2@infradead.org" <dwmw2@infradead.org>,
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 Marek Vasut <marek.vasut@gmail.com>, Richard Weinberger <richard@nod.at>,
 Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>
Subject: Re: [PATCH 3/4] mtd: mchp23k256: add partitioning support
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On Thu, Jun 01, 2017 at 09:30:07PM +0000, Chris Packham wrote:
> On 02/06/17 06:43, Brian Norris wrote:
> > On Wed, May 17, 2017 at 05:29:11PM +0200, Boris Brezillon wrote:
> >> Can we fix allocate_partition() to properly handle the
> >> master->erasesize == 0 case instead of doing that?
> >
> > Is everything actually ready for the eraseblock size to be 0?
> 
> That was my initial motivation for faking it.

Understood. I think it's probably better to avoid hacking drivers like
you were about to, but I was also curious if anyone had thought through
the implications of *not* forcing a non-zero size.

> > That would
> > seem surprising to many applications, I would think. Can you, for
> > instance, even use UBI on such a device?
> 
> I've tried ext2 and I believe Andrew has tried minix fs. We're talking 
> SRAM so UBI/UBIFS doesn't really provide much benefit for this use-case.

Right. But that's not necessarily true for all NO_ERASE devices, so we'd
probably want to think about that before allowing it.

Brian