[Qemu-devel] [PATCH 2/2] qxl: change rom so that 4096 < size < 8192

[Alon Levy <alevy@redhat.com>]

This is a simpler solution to 869981, where migration breaks since qxl's
rom bar size has changed. Instead of ignoring fields in QXLRom, which is what has
actually changed, we remove some of the modes, a mechanism already
accounted for by the guest. To reach exactly two pages and not one, we
remove two out of four orientations, the remaining are normal and right
turn (chosen arbitrarily). Leaving only normal would result in a single
page which would also break migration.

Added assertions to ensure changes in spice-protocol in the future
causing increase or decrease of page size will result in failure at
startup (could do this compile time also but not sure how).

Signed-off-by: Alon Levy <alevy@redhat.com>
---
 hw/qxl.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/hw/qxl.c b/hw/qxl.c
index 8611ee9..99b354a 100644
--- a/hw/qxl.c
+++ b/hw/qxl.c
@@ -88,9 +88,7 @@
 
 #define QXL_MODE_EX(x_res, y_res)                 \
     QXL_MODE_16_32(x_res, y_res, 0),              \
-    QXL_MODE_16_32(y_res, x_res, 1),              \
-    QXL_MODE_16_32(x_res, y_res, 2),              \
-    QXL_MODE_16_32(y_res, x_res, 3)
+    QXL_MODE_16_32(x_res, y_res, 1)
 
 static QXLMode qxl_modes[] = {
     QXL_MODE_EX(640, 480),
-- 
1.8.0.1