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Date: Tue, 20 Jan 2004 19:42:17 -0800
From: Kris Kennaway <kris@obsecurity.org>
To: Peter Schuller <peter.schuller@infidyne.com>
Message-ID: <20040121034217.GB29338@xor.obsecurity.org>
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Subject: Re: Unexpected soft update inconsistency
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On Tue, Jan 20, 2004 at 12:31:30AM +0100, Peter Schuller wrote:

> Do soft updates, or do they not, algorithmically guarantee filesystem=20
> meta-data consistency in the event of a crash?

If you have a power failure or similar unclean shutdown, then SU
guarantees consistency.  If there is a kernel panic or hardware
failure, all bets are off, because there is no way to be sure that the
kernel was writing the correct bits to the hardware prior to the
crash, or that the hardware was writing the correct bits to disk.

Kris

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