Hello, when we configure the VM network using tap device, the actual send and receive function is realized by writev and read system call. Is that right? But when I look into the E1000 ehternet emulation code, the start send function is start_xmit -> process_tx_desc->xmit_seg -> qemu_send_packet->qemu_deliver_packet. The qemu_deliver_packet is function traverse the sender list, calling each VlanClient's receive function(register when init). If for the e1000, the receive function registered is e1000_receive. If that flow is right, I have a puzzle on e1000_receive, where only cpu_physical_memory_write/read is called, which can invoke the start_xmit. Then how and when is the tap device send/recv function called where the actual packet delivered to harddevice? Am I clear above? And also , anyone can give me some light on when the packet send or receive request yielded in GUEST OS reach the QEMU e1000, What a role does the KVM play durning the network packet deliver? Thanks advance. -- BestRegards. YangLiang -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
