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

[Gerd Hoffmann]

  Hi,

> If you want to add hotplug to microvm, you can reuse the existing code
> for CPU and memory hotplug controllers, and write drivers for them in
> Linux's drivers/platform.  The drivers would basically do what the ACPI
> AML tells the interpreter to do.

How would the linux kernel detect those devices?

I guess that wouldn't be ACPI, seems everyone wants avoid it[1].

So device tree on x86?  Something else?

cheers,
  Gerd

[1] Not clear to me why, some minimal ACPI tables listing our
    devices (isa-serial, fw_cfg, ...) doesn't look unreasonable
    to me.  We could also make virtio-mmio discoverable that way.
    Also we could do acpi cpu hotplug without having to write those
    linux platform drivers.  We would need a sysbus-acpi device though,
    but given that most acpi code is already separated out so piix and
    q35 can share it it should not be that hard to wire up.