[PATCH 2/3] xen/igd: don't register rom bar twice

[Chuck Zmudzinski <brchuckz@xxxxxxx>]

This also fixes a failed assertion in pci [1] for Qemu
version 10 and higher when passing through an Intel
IGD with an option ROM to the guest.

[1] f6fc01c ("hw/pci: Assert a bar is not registered multiple times")

Fixes: 881213f ("xen, gfx passthrough: retrieve VGA BIOS to work")
Signed-off-by: Chuck Zmudzinski <brchuckz@xxxxxxx>
---
 hw/xen/xen_pt.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/hw/xen/xen_pt.c b/hw/xen/xen_pt.c
index 474606e..c3b6c1e 100644
--- a/hw/xen/xen_pt.c
+++ b/hw/xen/xen_pt.c
@@ -495,7 +495,8 @@ static int xen_pt_register_regions(XenPCIPassthroughState 
*s, uint16_t *cmd)
     }
 
     /* Register expansion ROM address */
-    if (d->rom.base_addr && d->rom.size) {
+    PCIIORegion region = s->dev.io_regions[PCI_ROM_SLOT];
+    if (!region.size && d->rom.base_addr && d->rom.size) {
         uint32_t bar_data = 0;
 
         /* Re-set BAR reported by OS, otherwise ROM can't be read. */
-- 
2.52.0