Re: regression: [PATCH] wifi: mac80211: set station RX-NSS on reconfig

[Johannes Berg <johannes@sipsolutions.net>]

On Fri, 2024-03-08 at 12:58 +0100, Andreas Tobler wrote:
> Hello Johannes, all.
> 
> with this commit[0] we encounter a performance regression in one of our 
> AP/STA tests. The performance drop is about 100Mbps+
> 
> Our setup is a hostap (2.10) configured AP on 802.11ac, channel 46. 
> (40MHz). The client connects via wpa (2.10) and then we produce traffic. 
> Before this commit, the throughput was around 250 Mbps, with this commit 
> the performance is now down to 135 Mbps.
> 
> The wifi cards we use are WLE600VX from compex, a ath10k based one. The 
> kernel we're on is 6.1.80. We've seen it on 6.6 too but didn't investigate.
> 
> Now, the ieee80211_sta_set_rx_nss() function has two FIXME comments. One 
> in where it handles the ht capability and one in the vht part. Both 
> FIXME's are: 'consider rx_highest?'
> 

I think you'll find that all that is unrelated, and this fixes it:

https://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next.git/commit/?id=a8bca3e9371dc5e276af4168be099b2a05554c2a

johannes