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Date: Thu, 30 Oct 2025 07:55:04 +0100
From: Christoph Hellwig <hch@lst.de>
To: Qu Wenruo <wqu@suse.com>
Cc: Christoph Hellwig <hch@lst.de>, Qu Wenruo <quwenruo.btrfs@gmx.com>,
	"Darrick J. Wong" <djwong@kernel.org>,
	Carlos Maiolino <cem@kernel.org>,
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	"Martin K. Petersen" <martin.petersen@oracle.com>,
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	linux-fsdevel@vger.kernel.org, linux-raid@vger.kernel.org,
	linux-block@vger.kernel.org, linux-btrfs@vger.kernel.org
Subject: Re: [PATCH 4/4] xfs: fallback to buffered I/O for direct I/O when
 stable writes are required
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References: <20251029071537.1127397-1-hch@lst.de> <20251029071537.1127397-5-hch@lst.de> <20251029155306.GC3356773@frogsfrogsfrogs> <20251029163555.GB26985@lst.de> <8f384c85-e432-445e-afbf-0d9953584b05@suse.com> <20251030055851.GA12703@lst.de> <04db952d-2319-4ef9-8986-50e744b00b62@gmx.com> <20251030064917.GA13549@lst.de> <a44566d9-4fef-43cc-b53e-bd102724344a@suse.com>
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On Thu, Oct 30, 2025 at 05:23:32PM +1030, Qu Wenruo wrote:
>> So what is your application going to do if the open fails?
>
> If it can not accept buffered fallback, error out.

Why would it not be able to accept that?