On Sat, Sep 16, 2023 at 1:03 AM Eugenio Pérez <epere...@redhat.com> wrote:
>
> This patch solves a few issues. The most obvious is that the feature
> set was done previous to ACKNOWLEDGE | DRIVER status bit set. Current
> vdpa devices are permissive with this, but it is better to follow the
> standard.
>
> Signed-off-by: Eugenio Pérez <epere...@redhat.com>
> ---
> net/vhost-vdpa.c | 14 ++++++++++----
> 1 file changed, 10 insertions(+), 4 deletions(-)
>
> diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
> index 51d8144070..4b30325977 100644
> --- a/net/vhost-vdpa.c
> +++ b/net/vhost-vdpa.c
> @@ -1270,8 +1270,7 @@ static int vhost_vdpa_probe_cvq_isolation(int
> device_fd, uint64_t features,
> uint64_t backend_features;
> int64_t cvq_group;
> uint8_t status = VIRTIO_CONFIG_S_ACKNOWLEDGE |
> - VIRTIO_CONFIG_S_DRIVER |
> - VIRTIO_CONFIG_S_FEATURES_OK;
> + VIRTIO_CONFIG_S_DRIVER;
> int r;
>
> ERRP_GUARD();
> @@ -1286,15 +1285,22 @@ static int vhost_vdpa_probe_cvq_isolation(int
> device_fd, uint64_t features,
> return 0;
> }
>
> + r = ioctl(device_fd, VHOST_VDPA_SET_STATUS, &status);
> + if (unlikely(r)) {
> + error_setg_errno(errp, -r, "Cannot set device status");
> + goto out;
> + }
> +
> r = ioctl(device_fd, VHOST_SET_FEATURES, &features);
> if (unlikely(r)) {
> - error_setg_errno(errp, errno, "Cannot set features");
> + error_setg_errno(errp, -r, "Cannot set features");
> goto out;
> }
>
Spec requires a re-read ?
"
Re-read device status to ensure the FEATURES_OK bit is still set:
otherwise, the device does not support our subset of features and the
device is unusable.
"
Thanks
> + status |= VIRTIO_CONFIG_S_FEATURES_OK;
> r = ioctl(device_fd, VHOST_VDPA_SET_STATUS, &status);
> if (unlikely(r)) {
> - error_setg_errno(errp, -r, "Cannot set status");
> + error_setg_errno(errp, -r, "Cannot set device status");
> goto out;
> }
>
> --
> 2.39.3
>
