PATCH: Adjust PCI rom code to handle more broken ROMs

[Jon Smirl <jonsmirl@gmail.com>]

There are ROMs reporting that their size exceeds their PCI ROM
resource window. This patch returns the minimum of the resource window
size or the size in the ROM.  An example of this breakage is the XGI
Volari Z7.

Signed-off-by: Jon Smirl <jonsmirl@gmail.com>
Patch is in an attachment since gmail will mangle the tabs.

-- 
Jon Smirl
jonsmirl@gmail.com

diff --git a/drivers/pci/rom.c b/drivers/pci/rom.c
--- a/drivers/pci/rom.c
+++ b/drivers/pci/rom.c
@@ -125,7 +125,9 @@ void __iomem *pci_map_rom(struct pci_dev
 		image += readw(pds + 16) * 512;
 	} while (!last_image);
 
-	*size = image - rom;
+	/* never return a size larger than the PCI resource window */
+	/* there are known ROMs that get the size wrong */
+	*size = min((size_t)(image - rom), *size);
 
 	return rom;
 }