virtio-pci: fix bus master work around on load

Commit c81131db15dd1844d0db1d51f3cd7a105cfd2cf3
detects old guests by comparing virtio and
PCI status. It attempts to do this on load,
as well, but load_config callback in a binding
is invoked too early and so the virtio status
isn't set yet.

We could add yet another callback to the
binding, to invoke after load, but it
seems easier to reuse the existing vmstate
callback.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Alexander Graf <agraf@suse.de>

diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
index ef655906016e69b27be219a7b75528c49762aa83..df10703b294fe45989b7b35acab7f158ed9d0dc6 100644 (file)
--- a/hw/virtio-pci.c
+++ b/hw/virtio-pci.c
@@ -160,13 +160,6 @@ static int virtio_pci_load_config(void * opaque, QEMUFile *f)
     if (proxy->vdev->config_vector != VIRTIO_NO_VECTOR) {
         return msix_vector_use(&proxy->pci_dev, proxy->vdev->config_vector);
     }
-
-    /* Try to find out if the guest has bus master disabled, but is
-       in ready state. Then we have a buggy guest OS. */
-    if ((proxy->vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
-        !(proxy->pci_dev.config[PCI_COMMAND] & PCI_COMMAND_MASTER)) {
-        proxy->flags |= VIRTIO_PCI_FLAG_BUS_MASTER_BUG;
-    }
     return 0;
 }
 
@@ -651,6 +644,12 @@ static void virtio_pci_vmstate_change(void *opaque, bool running)
     VirtIOPCIProxy *proxy = opaque;
 
     if (running) {
+        /* Try to find out if the guest has bus master disabled, but is
+           in ready state. Then we have a buggy guest OS. */
+        if ((proxy->vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) &&
+            !(proxy->pci_dev.config[PCI_COMMAND] & PCI_COMMAND_MASTER)) {
+            proxy->flags |= VIRTIO_PCI_FLAG_BUS_MASTER_BUG;
+        }
         virtio_pci_start_ioeventfd(proxy);
     } else {
         virtio_pci_stop_ioeventfd(proxy);

diff --git a/hw/virtio.h b/hw/virtio.h
index d0920a84c4cec047144bb83dd75c5b90081b4cde..bc722896c98e46feefb3135b886c5ac224bd881b 100644 (file)
--- a/hw/virtio.h
+++ b/hw/virtio.h
@@ -92,6 +92,7 @@ typedef struct {
     void (*save_queue)(void * opaque, int n, QEMUFile *f);
     int (*load_config)(void * opaque, QEMUFile *f);
     int (*load_queue)(void * opaque, int n, QEMUFile *f);
+    int (*load_done)(void * opaque, QEMUFile *f);
     unsigned (*get_features)(void * opaque);
     bool (*query_guest_notifiers)(void * opaque);
     int (*set_guest_notifiers)(void * opaque, bool assigned);