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Date: Thu, 9 Jan 2025 07:12:38 +0100
From: Christoph Hellwig <hch@lst.de>
To: Andrey Albershteyn <aalbersh@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>, linux-xfs@vger.kernel.org,
	djwong@kernel.org, david@fromorbit.com,
	Andrey Albershteyn <aalbersh@kernel.org>
Subject: Re: [RFC] Directly mapped xattr data & fs-verity
Message-ID: <20250109061238.GA16687@lst.de>
References: <20241229133350.1192387-1-aalbersh@kernel.org> <20250106154212.GA27933@lst.de> <prijdbxigrvzr5xsjviohbkb3gjzrans6yqzygncqrwdacfhcu@lhc3vtgd6ecw> <20250107165057.GA371@lst.de> <j7barlm3iix22ytjuu5y5mptfqzjme5pfdxk2a3vgb43ukoqxg@uhbobs5fs2uz>
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On Wed, Jan 08, 2025 at 10:20:59AM +0100, Andrey Albershteyn wrote:
> > Maybe we can used it for $HANDWAVE is not a good idea. 
> 
> > Hash based verification works poorly for mutable files, so we'd
> > rather have a really good argument for that.
> 
> hmm, why? Not sure I have an understanding of this

You need a consistent point in time to verify with your hash to have
a meaning.  How do you define that point for a mutable file?