From: "Jason J. Herne" <jjhe...@linux.vnet.ibm.com> virtio_ccw_{save|load}_config are missing code to save and restore a vdev's config_vector value. This causes some virtio devices to become disabled following a migration.
This patch fixes a bug whereby the qmp/hmp balloon command (virsh setmem) silently fails to update the guest's available memory because the device was not properly migrated. This will break compatibility, but vmstate_s390_cpu was bumped from version 2 to version 4 between v2.3.0 and v2.4.0 without a compat handler. Furthermore, there is no production environment yet so migration is fenced anyway between any relevant version of 2.3 and 2.4. Signed-off-by: Jason J. Herne <jjhe...@linux.vnet.ibm.com> Message-Id: <1433343843-803-1-git-send-email-jjhe...@linux.vnet.ibm.com> Reviewed-by: Michael S. Tsirkin <m...@redhat.com> Signed-off-by: Christian Borntraeger <borntrae...@de.ibm.com> --- hw/s390x/virtio-ccw.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c index ab629fe..ab5fc7f 100644 --- a/hw/s390x/virtio-ccw.c +++ b/hw/s390x/virtio-ccw.c @@ -1311,6 +1311,7 @@ static void virtio_ccw_save_config(DeviceState *d, QEMUFile *f) { VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d); SubchDev *s = dev->sch; + VirtIODevice *vdev = virtio_ccw_get_vdev(s); subch_device_save(s, f); if (dev->indicators != NULL) { @@ -1334,6 +1335,7 @@ static void virtio_ccw_save_config(DeviceState *d, QEMUFile *f) qemu_put_be32(f, 0); qemu_put_be64(f, 0UL); } + qemu_put_be16(f, vdev->config_vector); qemu_put_be64(f, dev->routes.adapter.ind_offset); qemu_put_byte(f, dev->thinint_isc); } @@ -1342,6 +1344,7 @@ static int virtio_ccw_load_config(DeviceState *d, QEMUFile *f) { VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d); SubchDev *s = dev->sch; + VirtIODevice *vdev = virtio_ccw_get_vdev(s); int len; s->driver_data = dev; @@ -1367,6 +1370,7 @@ static int virtio_ccw_load_config(DeviceState *d, QEMUFile *f) qemu_get_be64(f); dev->summary_indicator = NULL; } + qemu_get_be16s(f, &vdev->config_vector); dev->routes.adapter.ind_offset = qemu_get_be64(f); dev->thinint_isc = qemu_get_byte(f); if (s->thinint_active) { -- 2.3.0