Re: [RFC] cfg80211: Fix incompatible interfaces combination

[Johannes Berg <johannes@sipsolutions.net>]

Hi Mohammed,

> >> static const struct ieee80211_iface_limit a[] = {
> >>           { .max = 2,     .types = BIT(NL80211_IFTYPE_STATION) },
> >> };
> >>
> >> static const struct ieee80211_iface_limit b[] = {
> >>           { .max = 2,     .types = BIT(NL80211_IFTYPE_MESH_POINT) },
> >> };
> >>
> >> static const struct ieee80211_iface_combination if_comb[] = {
> >>           {.limits = a,
> >>           .n_limits = ARRAY_SIZE(a),
> >>           .max_interfaces = 2,
> >>           .num_different_channels = 1,
> >>           },
> >>           {.limits = b,
> >>           .n_limits = ARRAY_SIZE(b),
> >>           .max_interfaces = 2,
> >>           .num_different_channels = 1,
> >>           },
> >>
> >> };
> >>
> >> i could not add mesh interface if a managed interface is already there
> >> and vice versa. if this is the expected behavior, then fine.
> >
> > No, that's not expected! Another bug!

Actually, I'm sorry -- clearly I wasn't paying attention before -- it is
expected. The above means you can add two managed or two mesh interface,
but no combinations of them. Basically, the things in if_comb are XOR,
and the things inside each limit are AND.

johannes