@@ -48,6 +48,7 @@ typedef void (*hotplug_fn)(HotplugHandler *plug_handler,
* @unplug: unplug callback.
* Used for device removal with devices that implement
* asynchronous and synchronous (surprise) removal.
+ * @is_hotpluggable_bus: called to check if bus/its parent allow hotplug on bus
*/
struct HotplugHandlerClass {
/* <private> */
@@ -58,6 +59,7 @@ struct HotplugHandlerClass {
hotplug_fn plug;
hotplug_fn unplug_request;
hotplug_fn unplug;
+ bool (*is_hotpluggable_bus)(HotplugHandler *plug_handler, BusState *bus);
};
/**
@@ -812,7 +812,18 @@ void qbus_set_bus_hotplug_handler(BusState *bus);
static inline bool qbus_is_hotpluggable(BusState *bus)
{
- return bus->hotplug_handler;
+ HotplugHandler *plug_handler = bus->hotplug_handler;
+ bool ret = !!plug_handler;
+
+ if (plug_handler) {
+ HotplugHandlerClass *hdc;
+
+ hdc = HOTPLUG_HANDLER_GET_CLASS(plug_handler);
+ if (hdc->is_hotpluggable_bus) {
+ ret = hdc->is_hotpluggable_bus(plug_handler, bus);
+ }
+ }
+ return ret;
}
/**
@@ -161,6 +161,13 @@ PCIDevice *pcie_find_port_by_pn(PCIBus *bus, uint8_t pn)
return NULL;
}
+static bool pcie_slot_is_hotpluggbale_bus(HotplugHandler *plug_handler,
+ BusState *bus)
+{
+ PCIESlot *s = PCIE_SLOT(bus->parent);
+ return s->hotplug;
+}
+
static const TypeInfo pcie_port_type_info = {
.name = TYPE_PCIE_PORT,
.parent = TYPE_PCI_BRIDGE,
@@ -188,6 +195,7 @@ static void pcie_slot_class_init(ObjectClass *oc, void *data)
hc->plug = pcie_cap_slot_plug_cb;
hc->unplug = pcie_cap_slot_unplug_cb;
hc->unplug_request = pcie_cap_slot_unplug_request_cb;
+ hc->is_hotpluggable_bus = pcie_slot_is_hotpluggbale_bus;
}
static const TypeInfo pcie_slot_type_info = {
Currently the property may flip its state during VM bring up or just doesn't work as the name implies. In particular with PCIE root port that has 'hotplug={on|off}' property, and when it's turned off, one would expect 'hotpluggable' == false for any devices attached to it. Which is not the case since qbus_is_hotpluggable() used by the property just checks for presence of any hotplug_handler set on bus. The problem is that name BusState::hotplug_handler from its inception is misnomer, as it handles not only hotplug but also in many cases coldplug as well (i.e. generic wiring interface), and it's fine to have hotplug_handler set on bus while it doesn't support hotplug (ex. pcie-slot with hotplug=off). Another case of root port flipping 'hotpluggable' state when ACPI PCI hotplug is enabled in this case root port with 'hotplug=off' starts as hotpluggable and then later on, pcihp hotplug_handler clears hotplug_handler explicitly after checking root port's 'hotplug' property. So root-port hotpluggablity check sort of works if pcihp is enabled but is broken if pcihp is disabled. One way to deal with the issue is to ask hotplug_handler if bus it controls is hotpluggable or not. To do that add is_hotpluggable_bus() hook to HotplugHandler interface and use it in 'hotpluggable' property + teach pcie-slot to actually look into 'hotplug' property state before deciding if bus is hotpluggable. Signed-off-by: Igor Mammedov <imammedo@redhat.com> --- include/hw/hotplug.h | 2 ++ include/hw/qdev-core.h | 13 ++++++++++++- hw/pci/pcie_port.c | 8 ++++++++ 3 files changed, 22 insertions(+), 1 deletion(-)