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Date: Thu, 21 Aug 2025 08:01:34 -0600
From: Keith Busch <kbusch@kernel.org>
To: John Garry <john.g.garry@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>, Christoph Hellwig <hch@infradead.org>,
	"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: <aKcmvfECWdv6CedK@kbusch-mbp>
References: <20250714131713.GA8742@lst.de>
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 <6babdebb-45d1-4f33-b8b5-6b1c4e381e35@oracle.com>
 <20250715060247.GC18349@lst.de>
 <072b174d-8efe-49d6-a7e3-c23481fdb3fc@oracle.com>
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In-Reply-To: <bd7b1eea-18bc-431e-bc29-42b780ff3c31@oracle.com>

On Tue, Aug 19, 2025 at 12:42:01PM +0100, John Garry wrote:
> 
> If we always ignore AWUPF, I fear that lots of sound NVMe implementations
> will be excluded from HW atomics.

It's not that they're excluded from HW atomics. They're just excluded
from the block layer's attributes and guard rails. People were using
NVMe atomics long before those block layer features, at least.