public inbox for linux-mtd@lists.infradead.org
 help / color / mirror / Atom feed
From: Jamie Lokier <jamie@shareable.org>
To: Iwo Mergler <iwo@call-direct.com.au>
Cc: linux-mtd@lists.infradead.org, joern@logfs.org,
	dwmw2@infradead.org, Alexey Korolev <akorolev@infradead.org>,
	Matthieu CASTET <matthieu.castet@parrot.com>
Subject: Re: [BUG] JFFS2 power loss recovery issues on NAND
Date: Wed, 18 Jun 2008 13:19:36 +0100	[thread overview]
Message-ID: <20080618121936.GD305@shareable.org> (raw)
In-Reply-To: <48584DE9.3000709@call-direct.com.au>

Iwo Mergler wrote:
> Forgive my ignorance - does that mean that not everything in JFFS2 is 
> CRC protected?

I think every _individual_ record is CRC protected in JFFS2

_But_ that doesn't always detect file corruption.  If JFFS2 records
don't match their CRC, they are treated as if not there.

If there's corrupt data records, that causes holes in files.  There's
no I/O error reported to the application, just blocks of zero bytes.

There's no mechanism in JFFS2 to detect that.  It requires checksums
at a higher level than individual records.

-- Jamie

  reply	other threads:[~2008-06-18 12:19 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-06-10 13:57 [BUG] JFFS2 power loss recovery issues on NAND Alexey Korolev
2008-06-17  1:03 ` Iwo Mergler
2008-06-17  8:13   ` Matthieu CASTET
2008-06-17  9:24     ` Jörn Engel
2008-06-17 16:00       ` Alexey Korolev
2008-06-17 16:57         ` Jörn Engel
2008-06-17 23:51     ` Iwo Mergler
2008-06-18 12:19       ` Jamie Lokier [this message]
2008-06-18 12:33         ` David Woodhouse

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=20080618121936.GD305@shareable.org \
    --to=jamie@shareable.org \
    --cc=akorolev@infradead.org \
    --cc=dwmw2@infradead.org \
    --cc=iwo@call-direct.com.au \
    --cc=joern@logfs.org \
    --cc=linux-mtd@lists.infradead.org \
    --cc=matthieu.castet@parrot.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox