Probably a FAQ. I have implemented a prototype: * QEMU event for an in-guest issue (tools installation / crash etc), via fwcfg / vmcore (similar). (QEMU_PROCESS_EVENT_DBGTOOLS_CHANGED). * Qemu Process / QemuMonitor handling for same event. * Mapped this through to VIR_DOMAIN_EVENT_ID_DBG_TOOLS, * Corresponding changes to top level event handling. We would find this *very useful* in cases where vm migration, debugging and the like require co-operation with guest user-mode. Are you folks happy to countenance some simple, but top-level, event handling changes triggered by guest software, or is this considered a no no? Should I be burying the details somewhere in EVENT_TUNABLE instead? Patchsets also available ... MH.