[PATCH] virtio-vga: fix virtio-vga bar ordering

[Anthoine Bourgeois]

With virtio-vga, pci bar are reordered. Bar #2 is used for compatibility
with stdvga. By default, bar #2 is used by virtio modern io bar.
This bar is the last one introduce in the virtio pci bar layout and it's
crushed by the virtio-vga reordering. So virtio-vga and
modern-pio-notify are incompatible because virtio-vga failed to
initialize with this option.

This fix exchange the modern io bar with the modern memory bar,
replacing the msix bar that is never impacted anyway.

Signed-off-by: Anthoine Bourgeois <address@hidden>
---
 hw/display/virtio-vga.c | 2 +-
 hw/virtio/virtio-pci.c  | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/hw/display/virtio-vga.c b/hw/display/virtio-vga.c
index 2b4c2aa126..f5f8737c60 100644
--- a/hw/display/virtio-vga.c
+++ b/hw/display/virtio-vga.c
@@ -113,7 +113,7 @@ static void virtio_vga_base_realize(VirtIOPCIProxy 
*vpci_dev, Error **errp)
      * the stdvga mmio registers at the start of bar #2.
      */
     vpci_dev->modern_mem_bar_idx = 2;
-    vpci_dev->msix_bar_idx = 4;
+    vpci_dev->modern_io_bar_idx = 4;
 
     if (!(vpci_dev->flags & VIRTIO_PCI_FLAG_PAGE_PER_VQ)) {
         /*
diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index 4cb784389c..9c5efaa06e 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -1705,6 +1705,7 @@ static void virtio_pci_realize(PCIDevice *pci_dev, Error 
**errp)
      *
      *   region 0   --  virtio legacy io bar
      *   region 1   --  msi-x bar
+     *   region 2   --  virtio modern io bar
      *   region 4+5 --  virtio modern memory (64bit) bar
      *
      */
-- 
2.20.1