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See http://www.infradead.org/rpr.html Cc: Ohad Ben-Cohen , Mathieu Poirier , Arnd Bergmann , Amit Shah , Greg Kroah-Hartman , "Michael S. Tsirkin" , Arnaud Pouliquen , linux-kernel@vger.kernel.org, stable@vger.kernel.org, Bjorn Andersson , Christoph Hellwig , linux-remoteproc@vger.kernel.org, Suman Anna , virtualization@lists.linux-foundation.org X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" On Mon, Nov 16, 2020 at 01:07:28PM +0000, Alexander Lobakin wrote: > But lots of subsystems like netdev for example uses dev->parent for > DMA operations. I know that their pointers go directly to the > platform/PCI/etc. device, but still. Oh, every drivers is perfectly fine to use ->parent as it suits. The problem is when we have layered architectures, where this pokes a massive hole into the layering. > The only reason behind "fake" DMA devices for rproc is to be able to > reserve DMA memory through the Device Tree exclusively for only one > virtio dev like virtio_console or virtio_rpmsg_bus. That's why > they are present, are coercing DMA caps from physical dev > representor, and why questinable dma_declare_coherent_memory() > is still here and doesn't allow to build rproc core as a module. > I agree that this is not the best model obviously, and we should take > a look at it. As far as I can tell the series from Arnaud does the right thing here. _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization