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See http://www.infradead.org/rpr.html Cc: Jesper Dangaard Brouer , Daniel Borkmann , "Michael S. Tsirkin" , netdev@vger.kernel.org, John Fastabend , Alexei Starovoitov , virtualization@lists.linux-foundation.org, Christoph Hellwig , Eric Dumazet , Jakub Kicinski , bpf@vger.kernel.org, Paolo Abeni , "David S. Miller" 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, Jul 10, 2023 at 11:42:30AM +0800, Xuan Zhuo wrote: > This helper allows the driver change the dma mode to premapped mode. > Under the premapped mode, the virtio core do not do dma mapping > internally. > > This just work when the use_dma_api is true. If the use_dma_api is false, > the dma options is not through the DMA APIs, that is not the standard > way of the linux kernel. I have a hard time parsing this. More importantly having two modes seems very error prone going down the route. If the premapping is so important, why don't we do it always? _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization