Hi Jones: Thanks~It is great that Qemu has been working on that :-) On 18 August 2016 at 00:13, Andrew Jones <drjo...@redhat.com> wrote:
> On Wed, Aug 17, 2016 at 08:08:11PM +0800, Kevin Zhao wrote: > > Hi all, > > Now I'm investigating net device hot plug and disk hotplug for > > AArch64. For virtio , the default address is virtio-mmio. After Libvirt > > 1.3.5, user can explicitly specify the address-type to pci and so libvirt > > will pass the virtio-pci parameters to the Qemu. > > Both my host and guest OS is Debian8, and Qemu version is 2.6.0. > > Libvirt version is 1.3.5. > > For net-device, I change the address-type to pci, and libvirt pass > the > > command below: > > -device > > virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00: > 0d:25:25,bus=pci.2,addr=0x1 > > > > After booting, the eth0 device disappear(eth0 occur when the address > > is virtio-mmio), > > but I can find another net-device enp2s1, also it can't work for dhcp: > > Running lspci: 02:01.0 Ethernet controller: Red Hat, Inc Virtio network > > device > > I'm not sure whether it worked. > > > > For disk device,* when I change the address-type to pci, the whole > > qemu command is :* > > https://paste.fedoraproject.org/409553/, but the VM can not boot > > successfully. Does Qemu not support device disk of virtio-pci in AArch64 > > just as it in X86_64? > > Thanks~Since I am not very familiar with Qemu, really looking > forward > > to your response. > > > > Best Regards, > > Kevin Zhao > > libvirt 1.3.5 is a bit old. Later versions no longer unconditionally add > the i82801b11 bridge, which was necessary to use PCI devices with the PCIe > host bridge mach-virt has. IMO, libvirt and qemu still have a long way to > go in order to configure a base/standard mach-virt PCIe machine. > > Yeah, I am changing to libvirt 2.1.0, I find that I should use PCI by manually add the slots and bus to it. 1) If we want to support both PCIe devices and PCI, then things are messy. > Currently we propose dropping PCI support. mach-virt pretty much > exclusively uses virtio, which can be set to PCIe mode (virtio-1.0) > 2) root complex ports, switches (upstream/downstream ports) are currently > based on Intel parts. Marcel is thinking about creating generic models. > 3) libvirt needs to learn how to plug everything together, in proper PCIe > fashion, leaving holes for hotplug. > 4) Probably more... I forget all the different issues we discovered when > we started playing with this a few months ago. > > The good news is that x86 folk want all the same things for the q35 model. > mach-virt enthusiasts like us get to ride along pretty much for free. > > So, using virtio-pci with mach-virt and libvirt isn't possible right now, > not without manual changes to the XML. It might be nice to document how to > manually convert a guest, so developers who want to use virtio-pci don't > have to abandon libvirt. I'd have to look into that, or ask one of our > libvirt friends to help. Certainly the instructions would be for latest > libvirt though. > > As you said, that means that I can use PCIe as the bus for disk and net-device. I will try using pcie in libvirt. I will try the newest version of libvirt. Do I need to change <address type = 'pcie'> to enable it in AArch64 ? The pcie bus will be automatically assigned in libvirt ? > Finally, FWIW, with a guest kernel of 4.6.4-301.fc24.aarch64. The > following qemu command line works for me. > (notice the use of PCIe), and my network interface gets labeled enp0s1. > > $QEMU -machine virt-2.6,accel=kvm -cpu host \ > -m 1024 -smp 1 -nographic \ > -bios /usr/share/AAVMF/AAVMF_CODE.fd \ > -device ioh3420,bus=pcie.0,id=pcie.1,port=1,chassis=1 \ > -device ioh3420,bus=pcie.0,id=pcie.2,port=2,chassis=2 \ > -device > virtio-scsi-pci,disable-modern=off,disable-legacy=on,bus=pcie.1,addr=00.0,id=scsi0 > \ > -drive file=/home/drjones/.local/libvirt/images/fedora.qcow2, > format=qcow2,if=none,id=drive-scsi0-0-0-0 \ > -device scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,drive=drive- > scsi0-0-0-0,id=scsi0-0-0-0,bootindex=1 \ > -netdev user,id=hostnet0 \ > -device virtio-net-pci,disable-modern=off,disable-legacy=on,bus= > pcie.2,addr=00.0,netdev=hostnet0,id=net0 > > I prefer always using virtio-scsi for the disk, but a similar command > line can be used for a virtio-blk-pci disk. > > OK great! Because in Openstack Nova ,AArch64 need to realize the hotplug only with the virtio bus, so investigate the virtio-pci. :-) Thanks again! > Thanks, > drew >
