From af483cb870ad81dce8e10215e0add284fcc38da4 Mon Sep 17 00:00:00 2001
From: Michael S. Tsirkin <mst@redhat.com>
Date: Wed, 24 Feb 2010 21:09:45 +0200
Subject: [PATCH] msix: migration fix

Be careful to match mask/unmask callbacks from msix.
Fixes crash during migration.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 hw/msix.c |   16 +++++++++++++---
 1 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/hw/msix.c b/hw/msix.c
index 3fcf3a1..fafaf09 100644
--- a/hw/msix.c
+++ b/hw/msix.c
@@ -614,9 +614,19 @@ int msix_set_mask_notifier(PCIDevice *dev, unsigned vector, void *opaque)
     if (vector >= dev->msix_entries_nr || !dev->msix_entry_used[vector])
         return 0;

-    if (dev->msix_mask_notifier)
-        r = dev->msix_mask_notifier(dev, vector, opaque,
-                                    msix_is_masked(dev, vector));
+    if (dev->msix_mask_notifier && !msix_is_masked(dev, vector)) {
+        /* Mask previous notifier if any */
+        if (dev->msix_mask_notifier_opaque[vector]) {
+            r = dev->msix_mask_notifier(dev, vector,
+                                        dev->msix_mask_notifier_opaque[vector],
+                                        1);
+            assert(r >= 0);
+        }
+        /* Unmask new notifier, assumed to be masked at start */
+        if (opaque) {
+            r = dev->msix_mask_notifier(dev, vector, opaque, 0);
+        }
+    }
     if (r >= 0)
         dev->msix_mask_notifier_opaque[vector] = opaque;
     return r;
-- 
1.6.6.1