On Fri, Jun 24, 2016 at 12:27:57PM +0800, Chen Fan wrote: > hi all, > in openstack, we can use the pci passthrough feature now, refer to > https://wiki.openstack.org/wiki/Pci_passthrough > but we can't definitely specify the host pci driver is LEGACY_KVM or > newer VFIO, > new VFIO driver is more safer, and higher-performance user-space driver > than legacy kvm driver (pci-stub), the benefit relative to kvm > assignment driver > could refer to http://lwn.net/Articles/474088/. > In additional, VFIO driver provides the GPU passthrough as primary card > support. > I think it is more useful for further GPU passthrough support in > openstack. > > Openstack relies on the libvirt nodedev device configuration to do pci > passthrough, > with managed mode, the configured device is automatically detached and > re-attached > with KVM or VFIO driver that depended on the host driver modules > configuration, > so now we can't specify the driver in openstack to VFIO mode, I think > we should need > to add this feature support in openstack to get pci passhthrough more > scalability. > > a simply idea is to add a option in nova.conf HOST_PCI_MODEL = VFIO > /KVM to specify > the pci passthrough device driver is using VFIO driver. > any comments are welcome. :)
I don't see any reason to add a configuration option. If the host is capable of doing VFIO, libvirt will always aim to use VFIO in preference to the legacy system. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :| __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: [email protected]?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
