qxl: create slots on post_load in any state (fix RHBZ 740547)

Submitted by Alon Levy on Sept. 22, 2011, 12:33 p.m.

Details

Message ID 1316694826-20568-1-git-send-email-alevy@redhat.com
State New
Headers show

Commit Message

Alon Levy Sept. 22, 2011, 12:33 p.m.
If we migrate when the device is not in a native state the guest
still believes the slots are created, and will cause operations
that reference the slots, causing a "panic: virtual address out of range"
on the first of them. Easy to see by migrating in vga mode (with
a driver loaded, for instance windows cmd window in full screen mode)
and then exiting vga mode back to native mode will cause said panic.

Fixed by doing the slot recreation unconditionally at post_load

Signed-off-by: Alon Levy <alevy@redhat.com>
---
 hw/qxl.c |   12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)

Comments

Gerd Hoffmann Oct. 14, 2011, 1:01 p.m.
On 09/22/11 14:33, Alon Levy wrote:
> If we migrate when the device is not in a native state the guest
> still believes the slots are created, and will cause operations
> that reference the slots, causing a "panic: virtual address out of range"
> on the first of them. Easy to see by migrating in vga mode (with
> a driver loaded, for instance windows cmd window in full screen mode)
> and then exiting vga mode back to native mode will cause said panic.
>
> Fixed by doing the slot recreation unconditionally at post_load

Added to spice patch queue.

thanks,
   Gerd

Patch hide | download patch | download mbox

diff --git a/hw/qxl.c b/hw/qxl.c
index 6db2f1a..c5204d8 100644
--- a/hw/qxl.c
+++ b/hw/qxl.c
@@ -1684,6 +1684,12 @@  static int qxl_post_load(void *opaque, int version)
         qxl_mode_to_string(d->mode));
     newmode = d->mode;
     d->mode = QXL_MODE_UNDEFINED;
+    for (i = 0; i < NUM_MEMSLOTS; i++) {
+        if (!d->guest_slots[i].active) {
+            continue;
+        }
+        qxl_add_memslot(d, i, 0, QXL_SYNC);
+    }
     switch (newmode) {
     case QXL_MODE_UNDEFINED:
         break;
@@ -1691,12 +1697,6 @@  static int qxl_post_load(void *opaque, int version)
         qxl_enter_vga_mode(d);
         break;
     case QXL_MODE_NATIVE:
-        for (i = 0; i < NUM_MEMSLOTS; i++) {
-            if (!d->guest_slots[i].active) {
-                continue;
-            }
-            qxl_add_memslot(d, i, 0, QXL_SYNC);
-        }
         qxl_create_guest_primary(d, 1, QXL_SYNC);
 
         /* replay surface-create and cursor-set commands */