On Tue, Mar 24, 2020 at 07:24:39AM +0000, Ani Sinha wrote: > Hi All : > > I have been playing with Qemu trying to disable hot-unplug capability for conventional PCI. I have discussed this briefly on IRC and the plan is to have an option on the pci-pci bridge that would disable SHPC and ACPI hotplug capability for all the slots on that bus. I am _not_ trying to implement a per slot capability for conventional PCI as was previously posted for PCIE slots in this patch : https://lists.gnu.org/archive/html/qemu-devel/2020-03/msg01833.html (we do not need this atm). > > I am following the conversations which happened few weeks back here: > > https://lists.gnu.org/archive/html/qemu-devel/2020-02/msg00985.html > > To that end, I have been experimenting with Qemu using the patch I mention below. I have attached the virtio balloon driver with bus 1 which is attached to the pci bridge. > > <controller type='pci' index='0' model='pci-root'> > <alias name='pci.0'/> > </controller> > <controller type='pci' index='1' model='pci-bridge'> > <model name='pci-bridge'/> > <target chassisNr='1'/> > <alias name='pci.1'/> > <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/> > </controller> > <memballoon model='virtio'> > <stats period='30'/> > <alias name='balloon0'/> > <address type='pci' domain='0x0000' bus='0x02' slot='0x01' function='0x0'/> > </memballoon> > > > I am using a windows guest and from the guest I can see that the balloon driver is indeed attached to the pci bridge (see attached screenshot). > I still find Windows giving me an option to hot eject the pci balloon driver. > > So what am I doing wrong here? > [cid:87E6C01C-8B8C-4E24-AC4B-C0D746C2F605] > > The patch I am experimenting with (which is currently a hack) is > attached below. It is based off libvirt 4.5 and not the latest mainline. This is a patch against QEMU actually. I doubt many on the libvirt mailing list are familiar with the PCI / ACPI needs around hotplug, so it is probably best to re-send this patch to the QEMU mailing list and ask questions there. > > --- > hw/pci-bridge/pci_bridge_dev.c | 16 ++++++++-------- > 1 file changed, 8 insertions(+), 8 deletions(-) > > diff --git a/hw/pci-bridge/pci_bridge_dev.c b/hw/pci-bridge/pci_bridge_dev.c > index b2d861d..e706d49 100644 > --- a/hw/pci-bridge/pci_bridge_dev.c > +++ b/hw/pci-bridge/pci_bridge_dev.c > @@ -58,7 +58,7 @@ static void pci_bridge_dev_realize(PCIDevice *dev, Error **errp) > > pci_bridge_initfn(dev, TYPE_PCI_BUS); > > - if (bridge_dev->flags & (1 << PCI_BRIDGE_DEV_F_SHPC_REQ)) { > + if (0) {//bridge_dev->flags & (1 << PCI_BRIDGE_DEV_F_SHPC_REQ)) { > dev->config[PCI_INTERRUPT_PIN] = 0x1; > memory_region_init(&bridge_dev->bar, OBJECT(dev), "shpc-bar", > shpc_bar_size(dev)); > @@ -161,7 +161,7 @@ static Property pci_bridge_dev_properties[] = { > DEFINE_PROP_ON_OFF_AUTO(PCI_BRIDGE_DEV_PROP_MSI, PCIBridgeDev, msi, > ON_OFF_AUTO_AUTO), > DEFINE_PROP_BIT(PCI_BRIDGE_DEV_PROP_SHPC, PCIBridgeDev, flags, > - PCI_BRIDGE_DEV_F_SHPC_REQ, true), > + PCI_BRIDGE_DEV_F_SHPC_REQ, false), > DEFINE_PROP_END_OF_LIST(), > }; > > @@ -181,7 +181,7 @@ static const VMStateDescription pci_bridge_dev_vmstate = { > VMSTATE_END_OF_LIST() > } > }; > - > +#if 0 > static void pci_bridge_dev_hotplug_cb(HotplugHandler *hotplug_dev, > DeviceState *dev, Error **errp) > { > @@ -208,12 +208,12 @@ static void pci_bridge_dev_hot_unplug_request_cb(HotplugHandler *hotplug_dev, > } > shpc_device_hot_unplug_request_cb(hotplug_dev, dev, errp); > } > - > +#endif > static void pci_bridge_dev_class_init(ObjectClass *klass, void *data) > { > DeviceClass *dc = DEVICE_CLASS(klass); > PCIDeviceClass *k = PCI_DEVICE_CLASS(klass); > - HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass); > + //HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass); > > k->realize = pci_bridge_dev_realize; > k->exit = pci_bridge_dev_exitfn; > @@ -227,8 +227,8 @@ static void pci_bridge_dev_class_init(ObjectClass *klass, void *data) > dc->props = pci_bridge_dev_properties; > dc->vmsd = &pci_bridge_dev_vmstate; > set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories); > - hc->plug = pci_bridge_dev_hotplug_cb; > - hc->unplug_request = pci_bridge_dev_hot_unplug_request_cb; > + //hc->plug = pci_bridge_dev_hotplug_cb; > + //hc->unplug_request = pci_bridge_dev_hot_unplug_request_cb; > } > > static const TypeInfo pci_bridge_dev_info = { > @@ -238,7 +238,7 @@ static const TypeInfo pci_bridge_dev_info = { > .class_init = pci_bridge_dev_class_init, > .instance_finalize = pci_bridge_dev_instance_finalize, > .interfaces = (InterfaceInfo[]) { > - { TYPE_HOTPLUG_HANDLER }, > + //{ TYPE_HOTPLUG_HANDLER }, > { INTERFACE_CONVENTIONAL_PCI_DEVICE }, > { } > } > -- > 1.9.4 > Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
