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Date:   Thu, 19 May 2022 09:41:14 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Keith Busch <kbusch@kernel.org>
Cc:     Eric Biggers <ebiggers@kernel.org>, Keith Busch <kbusch@fb.com>,
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        axboe@kernel.dk, Kernel Team <Kernel-team@fb.com>, hch@lst.de,
        bvanassche@acm.org, damien.lemoal@opensource.wdc.com
Subject: Re: [PATCHv2 3/3] block: relax direct io memory alignment
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On Wed, May 18, 2022 at 10:56:04PM -0600, Keith Busch wrote:
> I'm surely missing something here. I know the bvecs are not necessarily lbs
> aligned, but why does that matter? Is there some driver that can only take
> exactly 1 bvec, but allows it to be unaligned? If so, we could take the segment
> queue limit into account, but I am not sure that we need to.

At least stacking drivers had all kinds of interesting limitations in
this area.  How much testing did this series get with all kinds of
interesting dm targets and md pesonalities?