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Date:   Thu, 31 Oct 2019 14:59:04 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Charles Machalow <csm10495@gmail.com>
Cc:     Christoph Hellwig <hch@lst.de>, linux-nvme@lists.infradead.org,
        marta.rybczynska@kalray.eu, Keith Busch <kbusch@kernel.org>,
        Jens Axboe <axboe@fb.com>, Sagi Grimberg <sagi@grimberg.me>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] nvme: change nvme_passthru_cmd64's result field.
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On Thu, Oct 31, 2019 at 06:55:33AM -0700, Charles Machalow wrote:
> Not quite sure what you mean by check for zero in the ioctl handler. I like
> the idea of being able to use the same struct for either the original or 64
> ioctls from userspace. I don't believe adding the explicit rsvd field
> allows that.

You might like the idea, but it fundamentally is a bad idea.  For example
you completely break architectures that do not support unaligned loads
and stores.