On 30.10.19 15:04, Johannes Berg wrote: > On Wed, 2019-10-30 at 14:40 +0100, Markus Theil wrote: >> Mesh interfaces are allowed to perform EDCA according to the standard >> 802.11-2016. > Well, they *have to* in a sense :-) > > [...] >> Changing beacons on the fly from user-space in these modes is only >> useful, if vendor-specific elements are used, which can change over time. >> >> All in all I can nevertheless understand your point, that these changes >> could be "wrong" from a pragmatic point of view. > No no, that's not even it. The problem is that you're focusing too much > on the standard without understanding how the stack works. > > Take the QoS parameters again for example. Setting them from userspace > is wrong because that data will immediately be forgotten and killed > again by the call to ieee80211_set_wmm_default() in that code. > > Or look at how the change_beacon call is handled - the data you set here > will never even be used for IBSS or mesh because in mac80211 > ieee80211_change_beacon() will quite possibly even crash when you call > it for a non-AP interface since it accesses sdata->u.ap.beacon without > any other checks. > > So while the *idea* of being able to change beacons or WMM parameters > *might* be correct, this kind of implementation is (fairly obviously) > completely wrong. > > johannes > Ok, thank you for the clarification :) Markus