Hi Johannes, On Tue, 2019-10-01 at 11:14 +0200, Johannes Berg wrote: > Hi, > > > > > Because userspace needs to know if this is supported? > > > > IFF_LIVE_ADDR_CHANGE is a private flag... AFAIK userspace has > > > > no > > > > way of > > > > obtaining this. > > > > > > Oh, annoying. > > > > > > But that doesn't really mean that nl80211 is an appropriate place > > > to > > > advertise it, IMHO? > > > > The intention of the flag was not soley related to > > CMD_CONNECT/CMD_AUTHENTICATE. Its an indication that the > > hardware/driver supports a live address change. If you don't want > > it > > here could you suggest a better location for it? > > I guess RTNL would be the right place? This can hardly be specific to > wireless, the flag comes from elsewhere.
I do see where your coming from, and maybe the answer is both RTNL and NL80211? In this context a NL80211 flag would mean something different than only putting a flag into RTNL. The NL80211 flag means this device supports changing the MAC while running and not offchannel/scanning. Which is what -EBUSY would mean in this context. Managing the offchannel/scanning work is only possible with a NL80211 application. An RTNL only application has no idea about scanning/offchannel work, so it has no way of knowing what -EBUSY means in the wireless device context, or a way to prevent this from happening (stopping scanning or offchannel before changing the MAC). Now, another example would be an RTNL application that only cares about non-wireless devices (like ethernet), and in this case it could benefit from some type of RTNL specific flag and not care about a NL80211 flag. Since there is no such application that cares about this RTNL flag (since it doesn't exist) I would say that adding NL80211 flag is the way to go. If someone wants to add an RTNL flag I would say that is appropriate too. But in terms of this feature, a NL80211 flag is really what fits best since the changes are wireless specific. Thanks, James > > johannes >
