Alex Williamson wrote: > On Mon, 2012-08-13 at 18:36 +0200, Andreas Hartmann wrote: [...] >> If I'm using your qemu instead of qemu from kvm-0.15 (opensuse package), >> this error comes up when passing through a PCIe device, which works >> absolutely fine with kvm 0.15. I would have expected, that your qemu >> works with the legacy way of handling pcie passthrough, too (with >> pci-stub module). > > VFIO cannot work with pci-stub, the backends are fundamentally > different. KVM making use pci-stub to hold onto a device is actually > one of the design problems that VFIO is meant to correct. The other > significant interface change is use of IOMMU groups, which is actually > why VFIO works for some of your uses while pci-assign does not. > >> This would mean, that all users get errors if they use the traditional >> way. IOW: there are changes needed (which?) to move from kvm 0.15 to >> your qemu version. > > But the way we solve this is to make libvirt understand how to do both. > Then it can probe the qemu/kvm binary and host system to figure out > which is supported and use the correct device options based on what it > finds. Trying to do both via the same qemu command line doesn't make > sense to me, especially when the device setup is so different. Ok! I thought your qemu version still would understand the old way via pci-stub. But this obviously was a misunderstanding of mine :-(. Thanks, Andreas -- 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
