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Date:   Tue, 2 Jun 2020 13:53:38 +0200
From:   Boris Brezillon <boris.brezillon@collabora.com>
To:     Bean Huo <huobean@gmail.com>
Cc:     miquel.raynal@bootlin.com, vigneshr@ti.com, s.hauer@pengutronix.de,
        derosier@gmail.com, Richard Weinberger <richard@nod.at>,
        linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org,
        Bean Huo <beanhuo@micron.com>
Subject: Re: [PATCH v6 0/5] Micron SLC NAND filling block
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On Tue, 02 Jun 2020 10:59:46 +0200
Bean Huo <huobean@gmail.com> wrote:

> On Tue, 2020-06-02 at 09:48 +0200, Boris Brezillon wrote:
> > Hi Bean,
> > 
> > On Mon, 01 Jun 2020 23:10:43 +0200
> > Bean Huo <huobean@gmail.com> wrote:
> >   
> > > Hi Richard 
> > > would you please help us confirm below question??  
> > 
> > Miquel suggested an approach that would allow us to deal with both
> > JFFS2
> > and UBI/UBIFS without having any FS/wear-leveling specific code at
> > the
> > NAND level, but you decided to ignore his comments. Sorry but there's
> > nothing we can do to help you if you don't listen to our
> > recommendations.  
> 
> Expose this issue to FS layer, it is not good idea. that will impact
> more code, and involve duplicated code.

Sorry but as far as I'm concerned, you've lost the right to have your
word in such design choices a long time ago. You can't deliberately lie
to us for several weeks/months and expect us to trust you (your
judgment) after that.

Back to the actual proposal, it's something that came from a discussion
we had with Miquel and Richard. It's certainly not perfect, but neither
is the option of hardcoding a quirk for JFFS2/UBI/UBIFS in the Micron
NAND driver.

BTW, I think you completely occluded Miquel's suggestion to have a
generic implementation at the MTD level for users who don't care about
the pattern that's written to those 'soon-to-be-erased' blocks. See,
that's one of the things I'm complaining about. You seem to ignore
(don't know if it's deliberate or not) some of the suggestions we do.

> > 
> > I've been quite disappointed by your behavior in the past, and it  
> 
> > continues. Recently you've taken Miquel's patches and claimed
> > ownership  
> did you seem my recent patch? you can ignore that see this.

I don't understand what you mean here, sorry.

> 
> 
> > on them (probably not intentionally, but still) while you were
> > clearly
> > unable to rework your original series the way I suggested (which
> > Miquel
> > did after seeing you would never send new versions).   
> 
> seriously?

Yes, seriously!

> 
> > And when Miquel
> > suggested a change to the implementation he had done based on the
> > discussion we had with Richard, you decided to ignore it and pursue
> > in
> > the original direction. So, quite frankly, I'm really not convinced
> > you
> > can conduct such a change.
> >   
> 
> As Miquel mentioned, we need richard's final comfirmation,
> If he agrees with this proposal, I give up my current patch.
> 

Actually, you need more than Richard's blessing. Miquel has to agree on
the NAND changes, and even if I can't block the solution, I think I can
at least give my opinion: anything that involves FS/wear-leveling
specific code at the NAND level should be avoided. Given the discussion
we had regarding JFFS2 and the cleanmarkers, I don't think we can come
up with a solution that's safe for every users, hence the proposal to
empower users with this responsibility.