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Date:   Mon, 24 Sep 2018 18:00:25 +0000
From:   Christopher Lameter <cl@linux.com>
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To:     Jens Axboe <axboe@kernel.dk>
cc:     Christoph Hellwig <hch@lst.de>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Ming Lei <tom.leiming@gmail.com>,
        linux-block <linux-block@vger.kernel.org>,
        linux-mm <linux-mm@kvack.org>,
        Linux FS Devel <linux-fsdevel@vger.kernel.org>,
        "open list:XFS FILESYSTEM" <linux-xfs@vger.kernel.org>,
        Dave Chinner <dchinner@redhat.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Ming Lei <ming.lei@redhat.com>
Subject: Re: block: DMA alignment of IO buffer allocated from slab
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On Mon, 24 Sep 2018, Jens Axboe wrote:

> The situation is making me a little uncomfortable, though. If we export
> such a setting, we really should be honoring it...

Various subsystems create custom slab arrays with their particular
alignment requirement for these allocations.