On Mon, Mar 04, 2024 at 02:46:06PM -0500, Jonah Palmer wrote:
> Prevent ioeventfd from being enabled/disabled when a virtio-pci
> device has negotiated the VIRTIO_F_NOTIFICATION_DATA transport
> feature.
>
> Due to ioeventfd not being able to carry the extra data associated with
> this feature, the ioeventfd should be left in a disabled state for
> emulated virtio-pci devices using this feature.
>
> Reviewed-by: Eugenio Pérez <[email protected]>
> Signed-off-by: Jonah Palmer <[email protected]>
I thought hard about this. I propose that for now,
instead of disabling ioevetfd silently we error out unless
user disabled it for us.
WDYT?
> ---
> hw/virtio/virtio-pci.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
> index d12edc567f..287b8f7720 100644
> --- a/hw/virtio/virtio-pci.c
> +++ b/hw/virtio/virtio-pci.c
> @@ -417,13 +417,15 @@ static void virtio_ioport_write(void *opaque, uint32_t
> addr, uint32_t val)
> }
> break;
> case VIRTIO_PCI_STATUS:
> - if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) {
> + if (!(val & VIRTIO_CONFIG_S_DRIVER_OK) &&
> + !virtio_vdev_has_feature(vdev, VIRTIO_F_NOTIFICATION_DATA)) {
> virtio_pci_stop_ioeventfd(proxy);
> }
>
> virtio_set_status(vdev, val & 0xFF);
>
> - if (val & VIRTIO_CONFIG_S_DRIVER_OK) {
> + if ((val & VIRTIO_CONFIG_S_DRIVER_OK) &&
> + !virtio_vdev_has_feature(vdev, VIRTIO_F_NOTIFICATION_DATA)) {
> virtio_pci_start_ioeventfd(proxy);
> }
>
> --
> 2.39.3
