On Mon, Nov 22, 2010 at 2:05 PM, Prasad Joshi <P.G.Joshi@xxxxxxxxxxxxxxxxxxxxx> wrote: > I was under the impression that the each virtio driver will have a frontend and backend part. The frontend part would be loaded in the Guest OS and the backend driver will be loaded in the Host OS. These two drivers will communicate with each other. The backend driver will then retransmit the actual request to correct driver. > > But seems like my understanding is wrong. > I attached a virtio disk to the Guest OS. When the Guest was booted, after creating a file system on the attached disk I mounted it. > > [prasad@Prasad-Fedora12-VM ~]$ lsmod | grep -i virtio > virtio_blk 7352 1 > virtio_pci 8680 0 > virtio_ring 6080 1 virtio_pci > virtio 5220 2 virtio_blk,virtio_pci > > But on the host machine no backend driver was loaded > > root@prasad-desktop:~/VMDisks# lsmod | grep -i virtio > root@prasad-desktop:~/VMDisks# > > Does this mean there is no explicit backend driver? A virtio device is a PCI adapter in the guest. That's why you see virtio_pci. The userspace QEMU process (called qemu-kvm or qemu) does device emulation and contains the virtio code you are looking for. See hw/virtio-blk.c in qemu-kvm.git. Stefan -- 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
