[PATCH] hw/pci/pci_bridge: ensure PCIe slots have only one slot

[Roman Kagan]

It's possible to create non-working configurations by attaching a device
to a derivative of PCIe slot (pcie-root-port, ioh3420, etc) and
specifying a slot number other that zero, e.g.:

    -device pcie-root-port,id=s0,... \
    -device virtio-blk-pci,bus=s0,addr=4,...

Make QEMU reject such configurations and only allow addr=0 on the
secondary bus of a PCIe slot.

Signed-off-by: Roman Kagan <rvkagan@yandex-team.ru>
---
 hw/pci/pci_bridge.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/hw/pci/pci_bridge.c b/hw/pci/pci_bridge.c
index da34c8ebcd..8b38d5ad3d 100644
--- a/hw/pci/pci_bridge.c
+++ b/hw/pci/pci_bridge.c
@@ -33,6 +33,7 @@
 #include "qemu/units.h"
 #include "hw/pci/pci_bridge.h"
 #include "hw/pci/pci_bus.h"
+#include "hw/pci/pcie_port.h"
 #include "qemu/module.h"
 #include "qemu/range.h"
 #include "qapi/error.h"
@@ -386,6 +387,10 @@ void pci_bridge_initfn(PCIDevice *dev, const char 
*typename)
     br->windows = pci_bridge_region_init(br);
     QLIST_INIT(&sec_bus->child);
     QLIST_INSERT_HEAD(&parent->child, sec_bus, sibling);
+
+    if (PCIE_SLOT(dev)) {
+        sec_bus->slot_reserved_mask = ~1u;
+    }
 }
 
 /* default qdev clean up function for PCI-to-PCI bridge */
-- 
2.36.1