On 02.04.19 10:12, Igor Mammedov wrote: > On Tue, 2 Apr 2019 09:56:13 +0200 > David Hildenbrand <david@xxxxxxxxxx> wrote: > >>>> >>>> I guess there will be quite some issues to be sorted out. >>>> >>> >>> That's what I'm getting from the several feedback I got so far. But the >>> more fundamental question is about the need for it. If you think this >>> goes in the right direction to make things more generic and >>> architecture agnostic, it might be worth the effort of trying to design >>> such solution. If instead you think this will be reinventing the wheel >>> and will not benefit any use case, then let's not waste some time on >>> this. >>> >> >> I think, the general cpu hotplug/unplug infrastructure in QEMU is pretty >> much generic. The only special case most probably is hotplugging >> different topologies. But the general "device_add $MODEL-$ARCH-cpu, >> id=$ID..." + device_del $ID is most probably easy to deal with by QEMU >> users. >> >> The main issue I think really is different hot(un)plug support per >> architecture. We heard that there might be a solution for s390x soon. I >> wonder what about other architectures. >> >> Of course, if people want to scrap ACPI completely, then > question is why one would want this and what we would be trying to achieve doing so? I'll direct that question to Sebastien. I remember it being one of the goals of NEMU. > > If ACPI is removed completely then one would need to provide > an alternative means to describe various HW which is main purpose of ACPI > ACPI bytecode methods is just a nice icing on top of that > which helps to abstract drivers from HW/firmware. > > Idea to use non standard DT instead looks like a horrible > alternative instead. > (well custom built kernel for fixed hw (thinking about cloud) can drop > ACPI and just hardcode everything for faster boot and skip any kind of > enumeration, but that's not applicable general purpose OS and probably > is not maintainable long-term). I could imagine that much information provided by ACPI is simply not needed in the case of kata containers. But as you correctly say, the question is for how long that will be true. -- Thanks, David / dhildenb
