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Date:   Wed, 17 Aug 2022 17:25:34 +0300
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Subject: Re: [RFC PATCH] nvmet-tcp: Don't kmap() pages which can't come from
 HIGHMEM
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To:     Keith Busch <kbusch@kernel.org>
Cc:     "Fabio M. De Francesco" <fmdefrancesco@gmail.com>,
        Christoph Hellwig <hch@lst.de>,
        Chaitanya Kulkarni <kch@nvidia.com>,
        linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org,
        Ira Weiny <ira.weiny@intel.com>
References: <20220816091808.23236-1-fmdefrancesco@gmail.com>
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From:   Sagi Grimberg <sagi@grimberg.me>
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>>> You should also remove the cmd's 'nr_mapped' field while you're at it,
>>> otherwise you'll hit the WARN in nvmet_tcp_free_cmd_buffers().
>>
>> Not remove nr_mapped because we use it to know the iovec entries, but
>> we can just remove the WARN statement.
> 
> It's only used locally within nvmet_tcp_map_pdu_iovec() after this change, so
> no need to carry it in struct nvmet_tcp_cmd anymore.

You are right, we can kill it.