Commit 9b3a35ec authored by Cornelia Huck's avatar Cornelia Huck Committed by Michael S. Tsirkin
Browse files

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: default avatarCornelia Huck <cohuck@redhat.com>
Message-Id: <20200707105446.677966-3-cohuck@redhat.com>
Cc: qemu-stable@nongnu.org
Acked-by: default avatarHalil Pasic <pasic@linux.ibm.com>
Reviewed-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent 7c78bdd7

hw/s390x/virtio-ccw.c

+6 −0
Original line number Diff line number Diff line
@@ -1121,6 +1121,12 @@ static void virtio_ccw_device_plugged(DeviceState *d, Error **errp) 
        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) {

        error_setg(errp, "The number of virtqueues %d "

                   "exceeds virtio limit %d", n,

hw/virtio/virtio-pci.c

+4 −0
Original line number Diff line number Diff line
@@ -1581,6 +1581,10 @@ static void virtio_pci_device_plugged(DeviceState *d, Error **errp) 
    }



    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)) {

            error_setg(errp, "VIRTIO_F_IOMMU_PLATFORM was supported by"

                       " neither legacy nor transitional device");