VGA: Don't register deprecated VBE range

Old versions of the BOCHs VGA BIOS (cira 2003) made use of VBE
registers at 0xff80/81.  In VBE API version 0xb0c2 these were
moved to 0x1ce/cf.  Unfortunately, QEMU still registers handlers
for the old range.  If a guest attempts to assign an I/O device
overlapping this region, QEMU exits with a hw_error.  Windows
guests seem to like to assign I/O devices to the high end of
the address space, so it's pretty easy to hot add an rtl8139
to a Win2k8 guest and trigger the bug.  I can't find any reason
to register these handlers, so let's remove the cruft.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

diff --git a/hw/vga.c b/hw/vga.c
index b5c7ee7..966185e 100644 (file)
--- a/hw/vga.c
+++ b/hw/vga.c
@@ -2313,13 +2313,6 @@ void vga_init(VGACommonState *s)
 
     register_ioport_write(0x1ce, 1, 2, vbe_ioport_write_index, s);
     register_ioport_write(0x1cf, 1, 2, vbe_ioport_write_data, s);
-
-    /* old Bochs IO ports */
-    register_ioport_read(0xff80, 1, 2, vbe_ioport_read_index, s);
-    register_ioport_read(0xff81, 1, 2, vbe_ioport_read_data, s);
-
-    register_ioport_write(0xff80, 1, 2, vbe_ioport_write_index, s);
-    register_ioport_write(0xff81, 1, 2, vbe_ioport_write_data, s);
 #else
     register_ioport_read(0x1ce, 1, 2, vbe_ioport_read_index, s);
     register_ioport_read(0x1d0, 1, 2, vbe_ioport_read_data, s);