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McKenney" , Konrad Rzeszutek Wilk , Muchun Song , Thomas Gleixner , Juergen Gross , Thomas Bogendoerfer , Andrii Anisov , linuxppc-dev@lists.ozlabs.org, Randy Dunlap , linux-mips@vger.kernel.org, iommu , Roman Skakun , Andrew Morton , "Maciej W. Rozycki" , Robin Murphy , Mike Rapoport 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: , From: Jan Beulich via iommu Reply-To: Jan Beulich Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On 17.09.2021 11:36, Roman Skakun wrote: > I use Xen PV display. In my case, PV display backend(Dom0) allocates > contiguous buffer via DMA-API to > to implement zero-copy between Dom0 and DomU. Why does the buffer need to be allocated by Dom0? If it was allocated by DomU, it could use grants to give the backend direct (zero-copy) access. Jan _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu