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Date:   Wed, 5 Jun 2019 12:09:28 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Sebastian Ott <sebott@linux.ibm.com>
Cc:     Christoph Hellwig <hch@lst.de>, Ming Lei <ming.lei@redhat.com>,
        Hannes Reinecke <hare@suse.com>, Jens Axboe <axboe@kernel.dk>,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: too large sg segments with commit 09324d32d2a08
Message-ID: <20190605100928.GA9828@lst.de>
References: <alpine.LFD.2.21.1906051057200.2118@schleppi>
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The problem is that we don't communicate the block level max_segment
size to the iommu, and the commit really is just the messenger.

I'll cook up a series to fix this as papering over it in every driver
does not seem sustainable.