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Date:   Tue, 29 Nov 2022 09:41:51 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Lei Rao <lei.rao@intel.com>
Cc:     kbusch@kernel.org, axboe@fb.com, hch@lst.de, sagi@grimberg.me,
        linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] nvme: clear the prp2 field of the nvme command.
Message-ID: <20221129084151.GA25609@lst.de>
References: <20221129014711.91305-1-lei.rao@intel.com>
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On Tue, Nov 29, 2022 at 09:47:11AM +0800, Lei Rao wrote:
> If the prp2 field is not filled in nvme_setup_prp_simple(), the prp2
> field is garbage data. According to nvme spec, the prp2 is reserved if
> the data transfer does not cross a memory page boundary. Writing a
> reserved coded value into a controller property field produces undefined
> results, so it needs to be cleared in nvme_setup_rw().

But this is not the right place to clear it, that needs to be done
in the place that sets up the PRPs, і.e. nvme_setup_prp_simple.