From: Michael S. Tsirkin <mst@redhat.com>
Date: Fri, 11 Oct 2019 13:58:03 +0000 (+0200)
Subject: virtio: new post_load hook
X-Git-Tag: v4.2.0-rc0~25^2~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=1dd713837cac8ec5a97d3b8492d72ce5ac94803c;p=thirdparty%2Fqemu.git

virtio: new post_load hook

Post load hook in virtio vmsd is called early while device is processed,
and when VirtIODevice core isn't fully initialized.  Most device
specific code isn't ready to deal with a device in such state, and
behaves weirdly.

Add a new post_load hook in a device class instead.  Devices should use
this unless they specifically want to verify the migration stream as
it's processed, e.g. for bounds checking.

Cc: qemu-stable@nongnu.org
Suggested-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mikhail Sennikovsky <mikhail.sennikovskii@cloud.ionos.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
---

diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 527df03bfd0..54a46e204cb 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -2291,6 +2291,13 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id)
     }
     rcu_read_unlock();
 
+    if (vdc->post_load) {
+        ret = vdc->post_load(vdev);
+        if (ret) {
+            return ret;
+        }
+    }
+
     return 0;
 }
 
diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
index 48e8d04ff6f..ca4f9c0bcc2 100644
--- a/include/hw/virtio/virtio.h
+++ b/include/hw/virtio/virtio.h
@@ -158,6 +158,12 @@ typedef struct VirtioDeviceClass {
      */
     void (*save)(VirtIODevice *vdev, QEMUFile *f);
     int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
+    /* Post load hook in vmsd is called early while device is processed, and
+     * when VirtIODevice isn't fully initialized.  Devices should use this instead,
+     * unless they specifically want to verify the migration stream as it's
+     * processed, e.g. for bounds checking.
+     */
+    int (*post_load)(VirtIODevice *vdev);
     const VMStateDescription *vmsd;
 } VirtioDeviceClass;