Re: [libvirt] [PATCH v2 2/4] qemu: Use generic PCIe Root Ports by default when available

On Thu, 2017-03-16 at 18:30 -0400, Laine Stump wrote: >> @@ -1861,7 +1863,12 @@ qemuDomainPCIControllerSetDefaultModelName(virDomainControllerDefPtr cont) >> *modelName = VIR_DOMAIN_CONTROLLER_PCI_MODEL_NAME_I82801B11_BRIDGE; >> break; >> case VIR_DOMAIN_CONTROLLER_MODEL_PCIE_ROOT_PORT: >> - *modelName = VIR_DOMAIN_CONTROLLER_PCI_MODEL_NAME_IOH3420; >> + /* Use generic PCIe Root Ports if available, falling back to >> + * ioh3420 otherwise */ >> + if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE_PCIE_ROOT_PORT)) >> + *modelName = VIR_DOMAIN_CONTROLLER_PCI_MODEL_NAME_PCIE_ROOT_PORT; >> + else >> + *modelName = VIR_DOMAIN_CONTROLLER_PCI_MODEL_NAME_IOH3420; > > I wonder if we should check caps for IOH3420 here just to be consistent > (and log an error if neither is available). I realize that's not the way > it worked before (existing code only checks the caps for a particular > device at the time we generate the commandline), but I'll be the first > to admit my original code was, err, "less than ideal". > > It's up to you though, add it or not. We already check when building the QEMU command line, which is the appropriate place IMHO. I'd rather not duplicate the check here as well.