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Date:   Wed, 23 Dec 2020 15:51:45 +0000
From:   Christoph Hellwig <hch@infradead.org>
To:     Pavel Begunkov <asml.silence@gmail.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Ming Lei <ming.lei@redhat.com>, linux-block@vger.kernel.org,
        Jens Axboe <axboe@kernel.dk>,
        Matthew Wilcox <willy@infradead.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        "Darrick J . Wong" <darrick.wong@oracle.com>,
        "Martin K . Petersen" <martin.petersen@oracle.com>,
        Jonathan Corbet <corbet@lwn.net>, linux-xfs@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, io-uring@vger.kernel.org,
        linux-kernel@vger.kernel.org, target-devel@vger.kernel.org,
        linux-scsi@vger.kernel.org, linux-doc@vger.kernel.org
Subject: Re: [PATCH v1 0/6] no-copy bvec
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On Wed, Dec 23, 2020 at 12:52:59PM +0000, Pavel Begunkov wrote:
> Can scatterlist have 0-len entries? Those are directly translated into
> bvecs, e.g. in nvme/target/io-cmd-file.c and target/target_core_file.c.
> I've audited most of others by this moment, they're fine.

For block layer SGLs we should never see them, and for nvme neither.
I think the same is true for the SCSI target code, but please double
check.