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Date:   Mon, 13 May 2019 16:02:46 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Akinobu Mita <akinobu.mita@gmail.com>
Cc:     linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org,
        Johannes Berg <johannes@sipsolutions.net>,
        Keith Busch <keith.busch@intel.com>, Jens Axboe <axboe@fb.com>,
        Christoph Hellwig <hch@lst.de>,
        Sagi Grimberg <sagi@grimberg.me>,
        Minwoo Im <minwoo.im.dev@gmail.com>,
        Kenneth Heitke <kenneth.heitke@intel.com>
Subject: Re: [PATCH v3 5/7] nvme-pci: add device coredump infrastructure
Message-ID: <20190513140246.GB24840@lst.de>
References: <1557676457-4195-1-git-send-email-akinobu.mita@gmail.com> <1557676457-4195-6-git-send-email-akinobu.mita@gmail.com>
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Usage of a scatterlist here is rather bogus as we never use
it for dma mapping.  Why can't you store the various pages in a
large bio_vec and then just issue that to the device in one
get log page command?  (or at least a few if MDTS kicks in?)