linux-ext4 - Re: [patch] ext2/3: document conditions when reliable operation is possible

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <200908262234.54586.rob@landley.net>
Date:	Wed, 26 Aug 2009 22:34:52 -0500
From:	Rob Landley <rob@...dley.net>
To:	Theodore Tso <tytso@....edu>
Cc:	Pavel Machek <pavel@....cz>, Ric Wheeler <rwheeler@...hat.com>,
	Florian Weimer <fweimer@....de>,
	Goswin von Brederlow <goswin-v-b@....de>,
	kernel list <linux-kernel@...r.kernel.org>,
	Andrew Morton <akpm@...l.org>, mtk.manpages@...il.com,
	rdunlap@...otime.net, linux-doc@...r.kernel.org,
	linux-ext4@...r.kernel.org, corbet@....net
Subject: Re: [patch] ext2/3: document conditions when reliable operation is possible

On Monday 24 August 2009 19:08:42 Theodore Tso wrote:
> And if your
> claim is that several hundred lines of fsck output detailing the
> filesystem's destruction somehow makes things all better, I suspect
> most users would disagree with you.

Suppose a small office makes nightly backups to an offsite server via rsync.  If 
a thunderstorm goes by causing their system to reboot twice in a 15 minute 
period, would they rather notice the filesystem corruption immediately upon 
reboot, or notice after the next rsync?

> In any case, depending on where the flash was writing at the time of
> the unplug, the data corruption could be silent anyway.

Yup.  Hopefully btrfs will cope less badly?  They keep talking about 
checksumming extents...

> Maybe this came as a surprise to you, but anyone who has used a
> compact flash in a digital camera knows that you ***have*** to wait
> until the led has gone out before trying to eject the flash card.

I doubt the cupholder crowd is going to stop treating USB sticks as magical 
any time soon, but I also wonder how many of them even remember Linux _exists_ 
anymore.

> I
> remember seeing all sorts of horror stories from professional
> photographers about how they lost an important wedding's day worth of
> pictures with the attendant commercial loss, on various digital
> photography forums.  It tends to be the sort of mistake that digital
> photographers only make once.

Professionals have horror stories about this issue, therefore documenting it 
is _less_ important?

Ok...

Rob
-- 
Latency is more important than throughput. It's that simple. - Linus Torvalds
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html