[PATCH] virtio: disable ioeventfd for record/replay

[Pavel Dovgalyuk]

virtio devices support separate iothreads waiting for
events from file descriptors. These are asynchronous
events that can't be recorded and replayed, therefore
this patch disables ioeventfd for all devices when
record or replay is enabled.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
---
 hw/virtio/virtio-pci.c |    6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index 094c36aa3e..76fbc111ea 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -37,6 +37,7 @@
 #include "qemu/range.h"
 #include "hw/virtio/virtio-bus.h"
 #include "qapi/visitor.h"
+#include "sysemu/replay.h"
 
 #define VIRTIO_PCI_REGION_SIZE(dev)     
VIRTIO_PCI_CONFIG_OFF(msix_present(dev))
 
@@ -1746,6 +1747,11 @@ static void virtio_pci_realize(PCIDevice *pci_dev, Error 
**errp)
         proxy->flags &= ~VIRTIO_PCI_FLAG_USE_IOEVENTFD;
     }
 
+    /* fd-based ioevents can't be synchronized in record/replay */
+    if (replay_mode != REPLAY_MODE_NONE) {
+        proxy->flags &= ~VIRTIO_PCI_FLAG_USE_IOEVENTFD;
+    }
+
     /*
      * virtio pci bar layout used by default.
      * subclasses can re-arrange things if needed.