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.