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Date: Sat, 14 Sep 2024 09:30:12 +0200
From: Christoph Hellwig <hch@lst.de>
To: Keith Busch <kbusch@meta.com>
Cc: axboe@kernel.dk, hch@lst.de, martin.petersen@oracle.com,
	linux-block@vger.kernel.org, linux-nvme@lists.infradead.org,
	linux-scsi@vger.kernel.org, sagi@grimberg.me,
	Keith Busch <kbusch@kernel.org>
Subject: Re: [PATCHv5 4/9] blk-integrity: consider entire bio list for
 merging
Message-ID: <20240914073011.GA30261@lst.de>
References: <20240913182854.2445457-1-kbusch@meta.com> <20240913182854.2445457-5-kbusch@meta.com>
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On Fri, Sep 13, 2024 at 11:28:49AM -0700, Keith Busch wrote:
> From: Keith Busch <kbusch@kernel.org>
> 
> If a bio is merged to a request, the entire bio list is merged, so don't
> temporarily detach it from its list when counting segments. In most
> cases, bi_next will already be NULL, so detaching is usually a no-op.
> But if the bio does have a list, the current code is miscounting the
> segments for the resulting merge.

As I explained in detail last round this is still wrong.  There is
no bio list here ever.