virtio: verify that legacy support is not accidentally on

If a virtio device does not have legacy support, make sure that
it is actually off, and bail out if not.

For virtio-pci, this means that any device without legacy support
that has been specified to modern-only (or that has been forced
to it) will work.

For virtio-ccw, this duplicates the check that is currently done
prior to realization for any device that explicitly specified no
support for legacy.

This catches devices that have not been fenced properly.

Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200707105446.677966-3-cohuck@redhat.com>
Cc: qemu-stable@nongnu.org
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Cornelia Huck 2020-07-07 12:54:46 +02:00 committed by Michael S. Tsirkin
parent 7c78bdd7a3
commit 9b3a35ec82
2 changed files with 10 additions and 0 deletions

View File

@ -1121,6 +1121,12 @@ static void virtio_ccw_device_plugged(DeviceState *d, Error **errp)
dev->max_rev = 0; dev->max_rev = 0;
} }
if (!virtio_ccw_rev_max(dev) && !virtio_legacy_allowed(vdev)) {
error_setg(errp, "Invalid value of property max_rev "
"(is %d expected >= 1)", virtio_ccw_rev_max(dev));
return;
}
if (virtio_get_num_queues(vdev) > VIRTIO_QUEUE_MAX) { if (virtio_get_num_queues(vdev) > VIRTIO_QUEUE_MAX) {
error_setg(errp, "The number of virtqueues %d " error_setg(errp, "The number of virtqueues %d "
"exceeds virtio limit %d", n, "exceeds virtio limit %d", n,

View File

@ -1581,6 +1581,10 @@ static void virtio_pci_device_plugged(DeviceState *d, Error **errp)
} }
if (legacy) { if (legacy) {
if (!virtio_legacy_allowed(vdev)) {
error_setg(errp, "device is modern-only, use disable-legacy=on");
return;
}
if (virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM)) { if (virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM)) {
error_setg(errp, "VIRTIO_F_IOMMU_PLATFORM was supported by" error_setg(errp, "VIRTIO_F_IOMMU_PLATFORM was supported by"
" neither legacy nor transitional device"); " neither legacy nor transitional device");