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See http://www.infradead.org/rpr.html Cc: intel-gfx@lists.freedesktop.org, Joonas Lahtinen , Linux Kernel Mailing List , Jani Nikula , Christoph Hellwig , iommu@lists.linux-foundation.org, Rodrigo Vivi , David Woodhouse X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Tue, Sep 08, 2020 at 06:36:19AM +0100, Christoph Hellwig wrote: > On Mon, Sep 07, 2020 at 09:18:50PM +0100, Tom Murphy wrote: > > Yeah we talked about passing an attr to map_sg to disable merging at > > the following microconfernce: > > https://linuxplumbersconf.org/event/7/contributions/846/ > > As far as I can remember everyone seemed happy with that solution. I > > won't be working on this though as I don't have any more time to > > dedicate to this. It seems Lu Baolu will take over this. > > I'm absolutely again passing a flag. Tha just invites further > abuse. We need a PCI ID based quirk or something else that can't > be as easily abused. Also, I looked at i915 and there are just three dma_map_sg callers. The two dmabuf related ones are fixed by Marek in his series, leaving just the one in i915_gem_gtt_prepare_pages, which does indeed look very fishy. But if that one is so hard to fix it can just be replaced by an open coded for_each_sg loop that contains manual dma_map_page calls. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu