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Date: Tue, 5 Aug 2025 16:52:11 -0600
From: Keith Busch <kbusch@kernel.org>
To: Keith Busch <kbusch@meta.com>
Cc: linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, hch@lst.de,
	axboe@kernel.dk
Subject: Re: [PATCH 1/2] block: accumulate segment page gaps per bio
Message-ID: <aJKLGy9UkVjJTIIQ@kbusch-mbp>
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On Tue, Aug 05, 2025 at 12:56:07PM -0700, Keith Busch wrote:
> +	bv = next->bio->bi_io_vec[0];
> +	bvprv = req->biotail->bi_io_vec[req->biotail->bi_vcnt - 1];

Hm, commit 7bcd79ac50d9d8 suggests I missed something obvious about not
being allowed to use 'bi_vcnt - 1' for the tail bvec of the previous
bio. I guess it's some stacking thing.