vga: Add mechanism to force the use of a shadow surface

This prevents surface sharing which will be necessary to
fix cirrus HW cursor support.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/hw/display/vga_int.h b/hw/display/vga_int.h
index ed69e064a8..72e00f2e0c 100644
--- a/hw/display/vga_int.h
+++ b/hw/display/vga_int.h
@@ -151,6 +151,7 @@ typedef struct VGACommonState {
     uint32_t last_scr_width, last_scr_height; /* in pixels */
     uint32_t last_depth; /* in bits */
     bool last_byteswap;
+    bool force_shadow;
     uint8_t cursor_start, cursor_end;
     bool cursor_visible_phase;
     int64_t cursor_blink_time;