Re: [PATCH 06/25] qemu: Add basic framework for 'microvm' machine type

On Tue, Feb 27, 2024 at 05:36:08PM +0100, Peter Krempa wrote: > @@ -4157,6 +4158,14 @@ qemuDomainDefAddDefaultDevices(virQEMUDriver *driver, > switch (def->os.arch) { > case VIR_ARCH_I686: > case VIR_ARCH_X86_64: > + /* don't add anything for microvm */ > + if (qemuDomainIsMicrovm(def)) { > + /* explicitly add 'none' USB controller */ > + usbModel = VIR_DOMAIN_CONTROLLER_MODEL_USB_NONE; > + addDefaultUSB = true; > + break; > + } I'm not terribly keen on seeing support for microvm officially introduced in libvirt. AFAIK nobody ever asked for it, and given that the intended use case for the machine type is specifically to have incredibly minimal, fast booting VMs, to the extent where trimmed out kernels and even custom firmware implementations are employed to shave every last possible microsecond off the boot time, I really don't expect that anyone would ever consider using libvirt to manage them. In other words, I think we should just keep pretending they don't exist and save a bit of code/complexity.