References: bsc#978164 CVE-2016-3710 XSA-179

From fbcff82cd7998f93556c28dfc63bbbd7b206c8ce Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kraxel@redhat.com>
Date: Tue, 26 Apr 2016 15:39:22 +0200
Subject: [PATCH 4/5] vga: update vga register setup on vbe changes

Call the new vbe_update_vgaregs() function on vbe configuration
changes, to make sure vga registers are up-to-date.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
---
 hw/vga.c | 1 +
 1 file changed, 1 insertion(+)

Index: xen-4.2.5-testing/tools/qemu-xen-dir-remote/hw/vga.c
===================================================================
--- xen-4.2.5-testing.orig/tools/qemu-xen-dir-remote/hw/vga.c
+++ xen-4.2.5-testing/tools/qemu-xen-dir-remote/hw/vga.c
@@ -763,6 +763,7 @@ static void vbe_ioport_write_data(void *
                     s->vbe_start_addr += x * ((s->vbe_regs[VBE_DISPI_INDEX_BPP] + 7) >> 3);
                 s->vbe_start_addr >>= 2;
             }
+            vbe_update_vgaregs(s);
             break;
         default:
             break;
