Re: [PATCH v4 0/8] Introduce the microvm machine type

[Pankaj Gupta <pagupta@redhat.com>]

> >>> Microvm is a machine type inspired by both NEMU and Firecracker, and
> >>> constructed after the machine model implemented by the latter.
> >>>
> >>> It's main purpose is providing users a minimalist machine type free
> >>> from the burden of legacy compatibility, serving as a stepping stone
> >>> for future projects aiming at improving boot times, reducing the
> >>> attack surface and slimming down QEMU's footprint.
> >>>
> >>> The microvm machine type supports the following devices:
> >>>
> >>>  - ISA bus
> >>>  - i8259 PIC
> >>>  - LAPIC (implicit if using KVM)
> >>>  - IOAPIC (defaults to kernel_irqchip_split = true)
> >>>  - i8254 PIT
> >>>  - MC146818 RTC (optional)
> >>>  - kvmclock (if using KVM)
> >>>  - fw_cfg
> >>>  - One ISA serial port (optional)
> >>>  - Up to eight virtio-mmio devices (configured by the user)
> >>
> >> So I assume also no ACPI (CPU/memory hotplug), correct?
> > 
> > Correct.
> > 
> >> @Pankaj, I think it would make sense to make virtio-pmem play with
> >> virtio-mmio/microvm.
> > 
> > That would be great. I'm also looking forward for virtio-mem (and an
> > hypothetical virtio-cpu) to eventually gain hotplug capabilities in
> > microvm.
> 
> @Pankaj, do you have time to look into the virtio-pmem thingy? I guess
> the virtio-mmio rapper shouldn't be too hard (very similar to the
> virtio-pci wrapper - luckily I insisted to make it work independently
> from PCI BARs and ACPI slots ;) ). The microvm bits would be properly
> setting up device memory and wiring up the hotplug handlers, similar as
> done in the other PC machine types (maybe that comes for free?).

Yes, I can look at.

> 
> virtio-pmem will allow (in read-only mode) to place the rootfs on a fake
> NVDIMM, as done e.g., in kata containers. We might have to include the
> virtio-pmem kernel module in the initramfs, shouldn't  be too hard. Not
> sure what else we'll need to make virtio-pmem get used as a rootfs.

Sure, will work on it.

Thanks,
Pankaj

> 
> > 
> > Thanks,
> > Sergio.
> > 
> 
> 
> --
> 
> Thanks,
> 
> David / dhildenb
> 
>