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Date: Tue, 15 Jul 2025 08:05:09 +0200
From: Christoph Hellwig <hch@lst.de>
To: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@lst.de>, John Garry <john.g.garry@oracle.com>,
	"Darrick J. Wong" <djwong@kernel.org>,
	linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org,
	linux-block@vger.kernel.org, linux-nvme@lists.infradead.org
Subject: Re: Do we need an opt-in for file systems use of hw atomic writes?
Message-ID: <20250715060509.GD18349@lst.de>
References: <20250714131713.GA8742@lst.de> <aHVuSU3TB4eNRq8V@dread.disaster.area>
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On Tue, Jul 15, 2025 at 06:53:29AM +1000, Dave Chinner wrote:
> This isn't a filesystem question - this is a question about what
> features the block device should expose by default to the
> user/filesystem by default.

It's both.  As I said before we've spent a lot of time making the file
systems less reliant on hardware getting everything right by adding
checksums (for metadata everywhere, and non-XFS file systems for data),
lsn verifications, etc.  And now we go all in to trust a new (in case
of nvme very much misdesigned) feature.

I'm perfectly fine offering that use, but I'm a lot less excited by
automatically using using it due to my deep mistrust of hardware.