On Thu, 27 Apr 2017 14:09:11 -0700 (PDT)
Stefano Stabellini <sstabell...@kernel.org> wrote:
> On Thu, 27 Apr 2017, Bruce Rogers wrote:
> > Commit f0c9d64a exposed the issue that with a xenfv machine using
> > pci passthrough, acpi cpi hotplug code was being executed by mistake.
> > Guard calls to acpi_pcihp_device_plug_cb (and corresponding
> > acpi_pcihp_device_unplug_cb) with a check for xen_enabled(). Without
> > this check I am seeing an error that the bus doesn't have the
> > acpi-pcihp-bsel property set.
> >
> > Signed-off-by: Bruce Rogers <brog...@suse.com>
> > ---
> > hw/acpi/piix4.c | 11 ++++++++---
> > 1 file changed, 8 insertions(+), 3 deletions(-)
> >
> > diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
> > index a553a7e..c409374 100644
> > --- a/hw/acpi/piix4.c
> > +++ b/hw/acpi/piix4.c
> > @@ -385,7 +385,10 @@ static void piix4_device_plug_cb(HotplugHandler
> > *hotplug_dev,
> > dev, errp);
> > }
> > } else if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {
> > - acpi_pcihp_device_plug_cb(hotplug_dev, &s->acpi_pci_hotplug, dev,
> > errp);
> > + if (!xen_enabled()) {
> > + acpi_pcihp_device_plug_cb(hotplug_dev, &s->acpi_pci_hotplug,
> > dev,
> > + errp);
> > + }
> > } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
> > if (s->cpu_hotplug_legacy) {
> > legacy_acpi_cpu_plug_cb(hotplug_dev, &s->gpe_cpu, dev, errp);
> > @@ -408,8 +411,10 @@ static void
> > piix4_device_unplug_request_cb(HotplugHandler *hotplug_dev,
> > acpi_memory_unplug_request_cb(hotplug_dev, &s->acpi_memory_hotplug,
> > dev, errp);
> > } else if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {
> > - acpi_pcihp_device_unplug_cb(hotplug_dev, &s->acpi_pci_hotplug, dev,
> > - errp);
> > + if (!xen_enabled()) {
> > + acpi_pcihp_device_unplug_cb(hotplug_dev, &s->acpi_pci_hotplug,
> > dev,
> > + errp);
> > + }
> > } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU) &&
> > !s->cpu_hotplug_legacy) {
> > acpi_cpu_unplug_request_cb(hotplug_dev, &s->cpuhp_state, dev,
> > errp);
>
> Wouldn't it be better to simply turn the error_setg("Unsupported bus...)
> in acpi_pcihp_device_plug_cb and acpi_pcihp_device_unplug_cb into debug
> printfs? After all, from this description it is clear that they are not
> an error conditions. PCI Passthough works correctly, right?
it's error condition if acpi hotplug is in use, so we should keep it
