All of lore.kernel.org
 help / color / mirror / Atom feed
From: Richard Weinberger <richard@nod.at>
To: Piotr Wojtaszczyk <wojtaszczykp@cumminsallison.com>
Cc: tglx@linutronix.de, linux-mtd@lists.infradead.org,
	boris.brezillon@bootlin.com, miquel.raynal@bootlin.com,
	beanhuo@micron.com
Subject: Re: [PATCH RFC] mtd: rawnand: Cure MICRON NAND partial erase issue
Date: Mon, 03 Dec 2018 20:02:16 +0100	[thread overview]
Message-ID: <1844020.iFgpUNDC3t@blindfold> (raw)
In-Reply-To: <2acabca0-cc7a-6655-8bd9-592b516f58a2@cumminsallison.com>

Am Montag, 3. Dezember 2018, 19:55:46 CET schrieb Piotr Wojtaszczyk:
> On Thu, 29 Nov 2018 22:12:50 +0100 (CET)
> Thomas Gleixner <tglx at linutronix.de> wrote:
> 
>  > On some Micron NAND chips block erase fails occasionaly despite the chip
>  > claiming that it succeeded. The flash block seems to be not completely
>  > erased and subsequent usage of the block results in hard to decode 
> and very
>  > subtle failures or corruption.
> 
> Doesn't UBI check block after erase in do_sync_erase()? Do the bitflips 
> develop over time?

You mean ubi_self_check_all_ff()? This is a very expensive self-check
which is disabled by default and makes only sense then you test UBI itself.
Also think of power-cuts, what happens if you face power-loss right
after mtd_erase() and before the check?

Finally, I'm not sure if you can detect partial erase right after
mtd_erase(). I fear failure happens after you write to that block.

Thanks,
//richard  

  reply	other threads:[~2018-12-03 19:02 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-12-03 18:55 [PATCH RFC] mtd: rawnand: Cure MICRON NAND partial erase issue Piotr Wojtaszczyk
2018-12-03 19:02 ` Richard Weinberger [this message]
2018-12-03 19:28   ` Piotr Wojtaszczyk
     [not found] <mailman.5261.1543570682.2376.linux-mtd@lists.infradead.org>
2018-11-30 16:40 ` Wojtaszczyk, Piotr
  -- strict thread matches above, loose matches on Subject: below --
2018-11-29 21:12 Thomas Gleixner
2018-12-02  7:29 ` Boris Brezillon
2018-12-02 14:22   ` Thomas Gleixner

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1844020.iFgpUNDC3t@blindfold \
    --to=richard@nod.at \
    --cc=beanhuo@micron.com \
    --cc=boris.brezillon@bootlin.com \
    --cc=linux-mtd@lists.infradead.org \
    --cc=miquel.raynal@bootlin.com \
    --cc=tglx@linutronix.de \
    --cc=wojtaszczykp@cumminsallison.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.