Toke Høiland-Jørgensen <toke@toke.dk> writes:

> The TXQ intermediate queues can cause packet reordering when more than
> one flow is active to a single station. Since some of the wifi-specific
> packet handling (notably sequence number and encryption handling) is
> sensitive to re-ordering, things break if they are applied before the
> TXQ.
>
> This splits up the TX handlers and fast_xmit logic into two parts: An
> early part and a late part. The former is applied before TXQ enqueue,
> and the latter after dequeue. The non-TXQ path just applies both parts
> at once.
>
> To avoid having to deal with fragmentation on dequeue, the split is set
> to be after the fragmentation handler. This means that some reordering
> of TX handlers is necessary, and some handlers had to be made aware of
> fragmentation due to this reordering.
>
> This approach avoids having to scatter special cases for when TXQ is
> enabled, at the cost of making the fast_xmit and TX handler code
> slightly more complex.
>
> Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>


And here's a version suitable for dropping into a LEDE build... Just
stick it in package/kernel/mac80211/patches.

-Toke