> From: Jason Wang <jasowang@xxxxxxxxxx> > Sent: Monday, July 4, 2022 12:47 AM > > > 在 2022/7/2 06:02, Parav Pandit 写道: > > > >> From: Zhu Lingshan <lingshan.zhu@xxxxxxxxx> > >> Sent: Friday, July 1, 2022 9:28 AM > >> > >> This commit adds a new vDPA netlink attribution > >> VDPA_ATTR_VDPA_DEV_SUPPORTED_FEATURES. Userspace can query > features > >> of vDPA devices through this new attr. > >> > >> Fixes: a64917bc2e9b vdpa: (Provide interface to read driver feature) > > Missing the "" in the line. > > I reviewed the patches again. > > > > However, this is not the fix. > > A fix cannot add a new UAPI. > > > > Code is already considering negotiated driver features to return the device > config space. > > Hence it is fine. > > > > This patch intents to provide device features to user space. > > First what vdpa device are capable of, are already returned by features > attribute on the management device. > > This is done in commit [1]. > > > > The only reason to have it is, when one management device indicates that > feature is supported, but device may end up not supporting this feature if > such feature is shared with other devices on same physical device. > > For example all VFs may not be symmetric after large number of them are > in use. In such case features bit of management device can differ (more > features) than the vdpa device of this VF. > > Hence, showing on the device is useful. > > > > As mentioned before in V2, commit [1] has wrongly named the attribute to > VDPA_ATTR_DEV_SUPPORTED_FEATURES. > > It should have been, > VDPA_ATTR_DEV_MGMTDEV_SUPPORTED_FEATURES. > > Because it is in UAPI, and since we don't want to break compilation of > > iproute2, It cannot be renamed anymore. > > > > Given that, we do not want to start trend of naming device attributes with > additional _VDPA_ to it as done in this patch. > > Error in commit [1] was exception. > > > > Hence, please reuse VDPA_ATTR_DEV_SUPPORTED_FEATURES to return > for device features too. > > > This will probably break or confuse the existing userspace? > It shouldn't break, because its new attribute on the device. All attributes are per command, so old one will not be confused either. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
