Jason Wang
2022-Jun-02 07:36 UTC
[PATCH 4/6] vDPA: !FEATURES_OK should not block querying device config space
On Thu, Jun 2, 2022 at 10:48 AM Zhu Lingshan <lingshan.zhu at intel.com> wrote:> > Users may want to query the config space of a vDPA device, > to choose a appropriate one for a certain guest. This means the > users need to read the config space before FEATURES_OK, and > the existence of config space contents does not depend on > FEATURES_OK.Quotes from the spec: "The device MUST allow reading of any device-specific configuration field before FEATURES_OK is set by the driver. This includes fields which are conditional on feature bits, as long as those feature bits are offered by the device."> > This commit removes FEATURES_OK blocker in vdpa_dev_config_fill() > which calls vdpa_dev_net_config_fill() for virtio-net > > Signed-off-by: Zhu Lingshan <lingshan.zhu at intel.com> > --- > drivers/vdpa/vdpa.c | 8 -------- > 1 file changed, 8 deletions(-) > > diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c > index c820dd2b0307..030d96bdeed2 100644 > --- a/drivers/vdpa/vdpa.c > +++ b/drivers/vdpa/vdpa.c > @@ -863,17 +863,9 @@ vdpa_dev_config_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, > { > u32 device_id; > void *hdr; > - u8 status; > int err; > > mutex_lock(&vdev->cf_mutex); > - status = vdev->config->get_status(vdev); > - if (!(status & VIRTIO_CONFIG_S_FEATURES_OK)) { > - NL_SET_ERR_MSG_MOD(extack, "Features negotiation not completed"); > - err = -EAGAIN; > - goto out; > - }So we had the following in vdpa_dev_net_config_fill(): features = vdev->config->get_driver_features(vdev); if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_NEGOTIATED_FEATURES, features, VDPA_ATTR_PAD)) return -EMSGSIZE; It looks to me we need to switch to using get_device_features() instead. Thanks> - > hdr = genlmsg_put(msg, portid, seq, &vdpa_nl_family, flags, > VDPA_CMD_DEV_CONFIG_GET); > if (!hdr) { > -- > 2.31.1 >