Re: [Qemu-devel] [patch 13/18] qemu: warn if PCI region is not power of two

[Marcelo Tosatti]

On Wed, Feb 04, 2009 at 02:38:05PM +0000, Paul Brook wrote:
> This should be an error. It is a requirement of the PCI spec, and not 
> something that's user configurable. Any odd sizes indicate a fairly serious 
> bug elsewhere in qemu.
> 
> Paul

qemu: bail out if PCI region is not power of two

Otherwise the PCI size for such regions can be calculated erroneously.

Signed-off-by: Marcelo Tosatti <address@hidden>

Index: trunk/hw/pci.c
===================================================================
--- trunk.orig/hw/pci.c
+++ trunk/hw/pci.c
@@ -249,6 +249,13 @@ void pci_register_io_region(PCIDevice *p
 
     if ((unsigned int)region_num >= PCI_NUM_REGIONS)
         return;
+
+    if (size & (size-1)) {
+        term_printf("ERROR: PCI region size must be pow2 "
+                    "type=0x%x, size=0x%x\n", type, size);
+        exit(1);
+    }
+
     r = &pci_dev->io_regions[region_num];
     r->addr = -1;
     r->size = size;