slow_map: minor improvements to ROM BAR handling

Commit Message

Michael S. Tsirkin Dec. 22, 2009, 4:05 p.m. UTC

None

Patch

diff --git a/hw/device-assignment.c b/hw/device-assignment.c
index 066fdb6..0c3c8f4 100644
--- a/hw/device-assignment.c
+++ b/hw/device-assignment.c
@@ -233,7 +233,8 @@  static void assigned_dev_iomem_map_slow(PCIDevice *pci_dev, int region_num,
     int m;
 
     DEBUG("slow map\n");
-    m = cpu_register_io_memory(slow_bar_read, slow_bar_write, region);
+    m = cpu_register_io_memory(slow_bar_read, region_num == PCI_ROM_SLOT ?
+                               NULL : slow_bar_write, region);
     cpu_register_physical_memory(e_phys, e_size, m);
 
     /* MSI-X MMIO page */