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Date:   Thu, 27 Aug 2020 08:02:37 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Amir Goldstein <amir73il@gmail.com>
Cc:     Brian Foster <bfoster@redhat.com>,
        fstests <fstests@vger.kernel.org>,
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        Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH 1/4] generic: require discard zero behavior for
 dmlogwrites on XFS
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On Thu, Aug 27, 2020 at 09:58:09AM +0300, Amir Goldstein wrote:
> I imagine that ext4 could also be burned by this.
> Do we have a reason to limit this requirement to xfs?
> I prefer to make it generic.

The whole idea that discard zeroes data is just completely broken.
Discard is a hint that is explicitly allowed to do nothing.