[libvirt] Re: [PATCH 10/12] Implement SCSI controller hotplug/unplug for QEMU

Hi, Daniel P. Berrange wrote: > From: Wolfgang Mauerer <wolfgang.mauerer(a)siemens.com&gt; > > This patch allows for explicit hotplug/unplug of SCSI controllers. > Ordinarily this is not required, since QEMU/libvirt will attach > a new SCSI controller whenever one is required. Allowing explicit > hotplug of controllers though, enables the caller to specify a > static PCI address, instead of auto-assigning the next available > PCI slot. Or it will when we have static PCI addressing. > > This patch is derived from Wolfgang Mauerer's disk controller > patch series. > > * src/qemu/qemu_driver.c: Support hotplug & unplug of SCSI > controllers > * src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h, > src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h, > src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add > new API for attaching PCI SCSI controllers (...) > +int qemuMonitorTextAttachPCIDiskController(qemuMonitorPtr mon, > + const char *bus, > + virDomainDevicePCIAddress *guestAddr) > +{ > + char *cmd = NULL; > + char *reply = NULL; > + int tryOldSyntax = 0; > + int ret = -1; > + > +try_command: > + if (virAsprintf(&cmd, "pci_add %s storage if=%s", > + (tryOldSyntax ? "0": "pci_addr=auto"), bus) < 0) { > + virReportOOMError(NULL); > + goto cleanup; > + } I just realised that qemu-kvm HEAD prohibits adding empty SCSI controllers currently, they consider this to be a bug. I've asked to revert the corresponding patch on qemu-devel, but if this does not happen, we will need to devise some other mechanism.