On Wed, Aug 23, 2017 at 07:14:42PM -0300, Eduardo Habkost wrote: > The following devices support both PCIe and legacy PCI, by > including special code to handle the QEMU_PCI_CAP_EXPRESS flag: > > * vfio-pci (is_express=1, but legacy PCI handled by > vfio_populate_device()) > * vmxnet3 (is_express=0, but PCIe handled by vmxnet3_realize()) > * pvscsi (is_express=0, but PCIe handled by pvscsi_realize()) > * virtio-pci (is_express=0, but PCIe handled by > virtio_pci_dc_realize(), and additional legacy PCI code at > virtio_pci_realize())
Oh, the rules are even messier than that: QEMU_PCI_CAP_EXPRESS controls _some_ of the code that makes a device become a PCI Express device, but not every case. In addition to vmxnet3, pvscsi and virtio-pci, PCIe caps initialization is conditional on hcd-xhci (see below). This means xhci is also a hybrid device. But it doesn't seem to clear QEMU_PCI_CAP_EXPRESS. Doesn't it mean pci_config_size() is broken if xhci is plugged to a legacy PCI bus? How does it affect migration? Full list of pci_endpoint_cap*_init() calls: hw/usb/hcd-xhci.c- if (pci_bus_is_express(dev->bus) || hw/usb/hcd-xhci.c- xhci_get_flag(xhci, XHCI_FLAG_FORCE_PCIE_ENDCAP)) { hw/usb/hcd-xhci.c: ret = pcie_endpoint_cap_init(dev, 0xa0); hw/net/vmxnet3.c- if (pci_is_express(pci_dev)) { hw/net/vmxnet3.c- if (pci_bus_is_express(pci_dev->bus)) { hw/net/vmxnet3.c: pcie_endpoint_cap_init(pci_dev, VMXNET3_EXP_EP_OFFSET); hw/net/vmxnet3.c- } hw/scsi/megasas.c- if (pci_is_express(dev)) { hw/scsi/megasas.c: pcie_endpoint_cap_init(dev, 0xa0); hw/scsi/megasas.c- } hw/scsi/vmw_pvscsi.c- if (pci_is_express(pci_dev) && pci_bus_is_express(pci_dev->bus)) { hw/scsi/vmw_pvscsi.c: pcie_endpoint_cap_init(pci_dev, PVSCSI_EXP_EP_OFFSET); hw/scsi/vmw_pvscsi.c- } hw/virtio/virtio-pci.c- if (pcie_port && pci_is_express(pci_dev)) { hw/virtio/virtio-pci.c- int pos; hw/virtio/virtio-pci.c- hw/virtio/virtio-pci.c: pos = pcie_endpoint_cap_init(pci_dev, 0); Note: on megasas, pci_endpoitn_cap_init() is conditional on pci_is_express(), but pci_is_express() will never be false on megasas-gen2 (because QEMU_PCI_CAP_EXPRESS is always set). Full list of unconditional pci_endpoint_cap*init() calls: hw/block/nvme.c: pcie_endpoint_cap_init(&n->parent_obj, 0x80); hw/net/e1000e.c: if (pcie_endpoint_cap_v1_init(pci_dev, e1000e_pcie_offset) < 0) { hw/pci-bridge/pcie_root_port.c: rc = pcie_cap_init(d, rpc->exp_offset, PCI_EXP_TYPE_ROOT_PORT, hw/pci-bridge/pcie_root_port.c- p->port, errp); hw/pci-bridge/xio3130_downstream.c: rc = pcie_cap_init(d, XIO3130_EXP_OFFSET, PCI_EXP_TYPE_DOWNSTREAM, hw/pci-bridge/xio3130_downstream.c- p->port, errp); hw/pci-bridge/xio3130_upstream.c: rc = pcie_cap_init(d, XIO3130_EXP_OFFSET, PCI_EXP_TYPE_UPSTREAM, hw/pci-bridge/xio3130_upstream.c- p->port, errp); hw/pci-host/xilinx-pcie.c: if (pcie_endpoint_cap_v1_init(dev, 0x80) < 0) { > > Signed-off-by: Eduardo Habkost <ehabk...@redhat.com> > --- > hw/net/vmxnet3.c | 5 +++++ > hw/scsi/vmw_pvscsi.c | 2 ++ > hw/vfio/pci.c | 5 +++++ > hw/virtio/virtio-pci.c | 5 +++++ > 4 files changed, 17 insertions(+) > > diff --git a/hw/net/vmxnet3.c b/hw/net/vmxnet3.c > index a19a7a3..61feacf 100644 > --- a/hw/net/vmxnet3.c > +++ b/hw/net/vmxnet3.c > @@ -2651,6 +2651,11 @@ static const TypeInfo vmxnet3_info = { > .instance_size = sizeof(VMXNET3State), > .class_init = vmxnet3_class_init, > .instance_init = vmxnet3_instance_init, > + .interfaces = (InterfaceInfo[]) { > + { INTERFACE_PCIE_DEVICE }, > + { INTERFACE_LEGACY_PCI_DEVICE }, > + { } > + }, > }; > > static void vmxnet3_register_types(void) > diff --git a/hw/scsi/vmw_pvscsi.c b/hw/scsi/vmw_pvscsi.c > index 77d8b6f..40dfffa 100644 > --- a/hw/scsi/vmw_pvscsi.c > +++ b/hw/scsi/vmw_pvscsi.c > @@ -1300,6 +1300,8 @@ static const TypeInfo pvscsi_info = { > .class_init = pvscsi_class_init, > .interfaces = (InterfaceInfo[]) { > { TYPE_HOTPLUG_HANDLER }, > + { INTERFACE_PCIE_DEVICE }, > + { INTERFACE_LEGACY_PCI_DEVICE }, > { } > } > }; > diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c > index 31e1edf..2b21391 100644 > --- a/hw/vfio/pci.c > +++ b/hw/vfio/pci.c > @@ -3023,6 +3023,11 @@ static const TypeInfo vfio_pci_dev_info = { > .class_init = vfio_pci_dev_class_init, > .instance_init = vfio_instance_init, > .instance_finalize = vfio_instance_finalize, > + .interfaces = (InterfaceInfo[]) { > + { INTERFACE_PCIE_DEVICE }, > + { INTERFACE_LEGACY_PCI_DEVICE }, > + { } > + }, > }; > > static void register_vfio_pci_dev_type(void) > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > index 8b0d6b6..8c0b6bf 100644 > --- a/hw/virtio/virtio-pci.c > +++ b/hw/virtio/virtio-pci.c > @@ -1958,6 +1958,11 @@ static const TypeInfo virtio_pci_info = { > .class_init = virtio_pci_class_init, > .class_size = sizeof(VirtioPCIClass), > .abstract = true, > + .interfaces = (InterfaceInfo[]) { > + { INTERFACE_PCIE_DEVICE }, > + { INTERFACE_LEGACY_PCI_DEVICE }, > + { } > + }, > }; > > /* virtio-blk-pci */ > -- > 2.9.4 > > -- Eduardo