[prefix] Ignore PCI autoboot device location if set to 00:00.0

qemu can load an option ROM which is not associated with a particular PCI device using the "-option-rom" syntax. Under these circumstances, we should ignore the PCI bus:dev.fn address that we expect to find in %ax on entry to the initialisation vector. Fix by using the PCI bus:dev.fn address only if it is non-zero. Since 00:00.0 will always be the host bridge, it can never be the address of a network card. Reported-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
ipxe · Mar 3, 2014 · ff1e7fc · ff1e7fc
1 parent c429bf0
commit ff1e7fc
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/src/arch/i386/core/pci_autoboot.c b/src/arch/i386/core/pci_autoboot.c
@@ -34,8 +34,10 @@ uint16_t __bss16 ( autoboot_busdevfn );
  */
 static void pci_autoboot_init ( void ) {
 
-	autoboot_device.bus_type = BUS_TYPE_PCI;
-	autoboot_device.location = autoboot_busdevfn;
+	if ( autoboot_busdevfn ) {
+		autoboot_device.bus_type = BUS_TYPE_PCI;
+		autoboot_device.location = autoboot_busdevfn;
+	}
 }
 
 /** PCI autoboot device initialisation function */