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Date:   Wed, 1 Jun 2022 10:12:26 -0600
From:   Keith Busch <kbusch@kernel.org>
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     Keith Busch <kbusch@fb.com>, linux-fsdevel@vger.kernel.org,
        linux-block@vger.kernel.org, linux-nvme@lists.infradead.org,
        axboe@kernel.dk, Kernel Team <Kernel-team@fb.com>, hch@lst.de,
        bvanassche@acm.org, damien.lemoal@opensource.wdc.com,
        pankydev8@gmail.com
Subject: Re: [PATCHv5 00/11] direct-io dma alignment
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On Wed, Jun 01, 2022 at 08:28:31AM -0600, Keith Busch wrote:
> On Wed, Jun 01, 2022 at 12:11:40AM -0700, Eric Biggers wrote:
> > I still don't think you've taken care of all the assumptions that bv_len is a
> > multiple of logical block size, or at least SECTOR_SIZE.  Try this:
> > 
> > 	git grep -E 'bv_len (>>|/)'
> 
> There are only 8 drivers that set the request_queue's dma alignment, which are
> the only ones that could be affected from this patch series.

It's actually even simpler to audit than that. Of the 8 drivers that explicitly
set dma alignment, only 3 set it to something smaller than a sector size. None
of them assume any particular bv_len, so I think we're fine.