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[80.230.79.166]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-43796abcda5sm59310906f8f.19.2026.02.20.02.03.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Feb 2026 02:03:23 -0800 (PST) Date: Fri, 20 Feb 2026 05:03:20 -0500 From: "Michael S. Tsirkin" To: Parav Pandit Cc: Bill Mills , "virtio-comment@lists.linux.dev" , Bertrand Marquis , "Edgar E . Iglesias" , Arnaud Pouliquen , Viresh Kumar , Alex Bennee , Armelle Laine Subject: Re: [PATCH v1 0/4] virtio-msg transport layer Message-ID: <20260220050136-mutt-send-email-mst@kernel.org> References: <20260126163230.1122685-1-bill.mills@linaro.org> <20260219185034-mutt-send-email-mst@kernel.org> Precedence: bulk X-Mailing-List: virtio-comment@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: 54LvFsLl46tGSqF1Jx5-Xak39MM4yAjkwWXwQ2N0Wto_1771581805 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Fri, Feb 20, 2026 at 06:13:55AM +0000, Parav Pandit wrote: > > > 4. I dont find the transport messages to read and write to the driver memory supplied in VIRTIO_MSG_SET_VQUEUE addresses to operate > > the virtqueues. > > > Dont we need VIRTIO_MEM_READ, VIRTIO_MEM_WRITE request and response? > > > > surely this can be an optional transport feature bit. > > > How is this optional? > How can one implement a transport without defining the basic data transfer semantics? > For example for TCP transporting, driver side OS is implementing header format foo, and device side is using header format bar. > How does it work? I'm not sure what do foo/bar refer to, or what TCP transporting means. The simplest way to do TCP on top of virtio is to layer it above virtio net. That uses VQs for data transfers. -- MST