Recent commits made it so that pci-root controllers for pSeries guests are automatically assigned the spapr-pci-host-bridge model name; however, that prevents guests to migrate to older versions of libvirt which don't know about that model name at all, which at the moment is all of them :) To avoid the issue, just strip the model name from PHBs when formatting the migratable XML; guests that use more than one PHB are not going to be migratable anyway. Signed-off-by: Andrea Bolognani <abologna@xxxxxxxxxx> --- src/conf/domain_conf.c | 25 ++++++++++++++++++++++++- 1 file changed, 24 insertions(+), 1 deletion(-) diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index d88a88e..b5ab97a 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -21813,7 +21813,30 @@ virDomainControllerDefFormat(virBufferPtr buf, } if (def->type == VIR_DOMAIN_CONTROLLER_TYPE_PCI) { - if (def->opts.pciopts.modelName != VIR_DOMAIN_CONTROLLER_PCI_MODEL_NAME_NONE) { + bool formatModelName = true; + + if (def->opts.pciopts.modelName == VIR_DOMAIN_CONTROLLER_PCI_MODEL_NAME_NONE) + formatModelName = false; + + /* Historically, libvirt didn't support specifying a model name for + * pci-root controllers; starting from 3.6.0, however, pSeries guests + * use pci-root controllers with model name spapr-pci-host-bridge to + * represent all PHBs, including the default one. + * + * In order to allow migration of pSeries guests from older libvirt + * versions and back, we don't format the model name in the migratable + * XML if it's spapr-pci-host-bridge, thus making "no model name" and + * "spapr-pci-host-bridge model name" basically equivalent. + * + * The spapr-pci-host-bridge device is specific to pSeries. + */ + if (def->model == VIR_DOMAIN_CONTROLLER_MODEL_PCI_ROOT && + def->opts.pciopts.modelName == VIR_DOMAIN_CONTROLLER_PCI_MODEL_NAME_SPAPR_PCI_HOST_BRIDGE && + flags & VIR_DOMAIN_DEF_FORMAT_MIGRATABLE) { + formatModelName = false; + } + + if (formatModelName) { modelName = virDomainControllerPCIModelNameTypeToString(def->opts.pciopts.modelName); if (!modelName) { virReportError(VIR_ERR_INTERNAL_ERROR, -- 2.7.5 -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list