On Mon, 1 Jul 2024 14:27:50 +0000 "Gao,Shiyuan" <gaoshiy...@baidu.com> wrote:
> > > > > If I want to use ACPI PCI hotplug in the pxb bridge, what else need > > > > > to be done? > > > > > > > > does it have to be hotplug directly into pxb or > > > > would be it be sufficient to have hotplug support > > > > on pci-bridge attached to a pxb? > > > > > > It's sufficient to hotplug support on pci-bridge attached to a pxb. > > > > ... but I guess using this instead would be better anyway? > > https://lore.kernel.org/all/20220422135101.65796...@redhat.com/t/#r831d589f243c24334a09995620b74408847a87a0 > > According this message, It seems that the current QEMU does not support it > yet. > I tried to hotplug on pci-bridge attached to a pxb, no device found in the > guest. SHPC works for q35, which provides _OSC. It is broken for pc machine though, since machine lacks either _OSC or OSHP. Theoretically SHPC should still work for hotplugged bridges (i.e. with ACPI hotplug enabled, when one hotplugs a bridge into pci.0, but I haven't tried that lately) I'm still not sure if we should make OSHP global, or put it only under bridges that have shcp=on && don't have ACPI hotplug. The later seems cleaner though. > > > > take care, > > Gerd >
