From: Ying Fang <fangying1@huawei.com>

QEMU will abort when vhost-user process is restarted during migration when
vhost_log_global_start/stop is called. The reason is clear that
vhost_dev_set_log returns -1 because network connection is temporarily lost.
To handle this situation, let's cancel migration and report it to user.

Signed-off-by: Ying Fang <fangying1@huawei.com>
---
 hw/virtio/vhost.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index ddc42f0..a9d1895 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -27,6 +27,7 @@
 #include "hw/virtio/virtio-access.h"
 #include "migration/blocker.h"
 #include "sysemu/dma.h"
+#include "migration/migration.h"
 
 /* enabled until disconnected backend stabilizes */
 #define _VHOST_DEBUG 1
@@ -882,20 +883,24 @@ static int vhost_migration_log(MemoryListener *listener, int enable)
 static void vhost_log_global_start(MemoryListener *listener)
 {
     int r;
+    Error *errp = NULL;
 
     r = vhost_migration_log(listener, true);
     if (r < 0) {
-        abort();
+        error_setg(&errp, "Failed to start vhost migration log");
+        migrate_fd_error(migrate_get_current(), errp);
     }
 }
 
 static void vhost_log_global_stop(MemoryListener *listener)
 {
     int r;
+    Error *errp = NULL;
 
     r = vhost_migration_log(listener, false);
     if (r < 0) {
-        abort();
+        error_setg(&errp, "Failed to stop vhost migration log");
+        migrate_fd_error(migrate_get_current(), errp);
     }
 }
 
-- 
2.10.0.windows.1