pc: Support coldplugging of virtio-pmem-pci devices on all buses

E.g., with "pc-q35-4.2", trying to coldplug a virtio-pmem-pci devices
results in
    "virtio-pmem-pci not supported on this bus"

Reasons is, that the bus does not support hotplug and, therefore, does
not have a hotplug handler. Let's allow coldplugging virtio-pmem devices
on such buses. The hotplug order is only relevant for virtio-pmem-pci
when the guest is already alive and the device is visible before
memory_device_plug() wired up the memory device bits.

Hotplug attempts will still fail with:
    "Error: Bus 'pcie.0' does not support hotplugging"

Hotunplug attempts will still fail with:
    "Error: Bus 'pcie.0' does not support hotplugging"

Reported-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20200626072248.78761-2-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
David Hildenbrand 2020-06-26 09:22:28 +02:00 committed by Michael S. Tsirkin
parent dd8eeb9671
commit af1d039f6d

View file

@ -1643,13 +1643,13 @@ static void pc_virtio_pmem_pci_pre_plug(HotplugHandler *hotplug_dev,
HotplugHandler *hotplug_dev2 = qdev_get_bus_hotplug_handler(dev);
Error *local_err = NULL;
if (!hotplug_dev2) {
if (!hotplug_dev2 && dev->hotplugged) {
/*
* Without a bus hotplug handler, we cannot control the plug/unplug
* order. This should never be the case on x86, however better add
* a safety net.
* order. We should never reach this point when hotplugging on x86,
* however, better add a safety net.
*/
error_setg(errp, "virtio-pmem-pci not supported on this bus.");
error_setg(errp, "virtio-pmem-pci hotplug not supported on this bus.");
return;
}
/*
@ -1658,7 +1658,7 @@ static void pc_virtio_pmem_pci_pre_plug(HotplugHandler *hotplug_dev,
*/
memory_device_pre_plug(MEMORY_DEVICE(dev), MACHINE(hotplug_dev), NULL,
&local_err);
if (!local_err) {
if (!local_err && hotplug_dev2) {
hotplug_handler_pre_plug(hotplug_dev2, dev, &local_err);
}
error_propagate(errp, local_err);
@ -1676,9 +1676,11 @@ static void pc_virtio_pmem_pci_plug(HotplugHandler *hotplug_dev,
* device bits.
*/
memory_device_plug(MEMORY_DEVICE(dev), MACHINE(hotplug_dev));
hotplug_handler_plug(hotplug_dev2, dev, &local_err);
if (local_err) {
memory_device_unplug(MEMORY_DEVICE(dev), MACHINE(hotplug_dev));
if (hotplug_dev2) {
hotplug_handler_plug(hotplug_dev2, dev, &local_err);
if (local_err) {
memory_device_unplug(MEMORY_DEVICE(dev), MACHINE(hotplug_dev));
}
}
error_propagate(errp, local_err);
}