Hi! On OpenWrt, between these versions: https://dev.openwrt.org/log/branches/barrier_breaker?action=stop_on_copy&mode=stop_on_copy&rev=44952&stop_rev=42475&limit=200&mail_addr=&mail_addr_confirm= there was a regression in how iw set bitrates operate. Because I suspect it is an upstream issue, I am reporting it here. With previous version of our firmware image, I was using the /etc/hotplug.d/iface/30-bitrates script you can see in this file: https://github.com/cloyne/network/blob/349297c8bfd115aa68e3b8c47bb3a7197f1e777f/unifi/README.md The goal was to limit on all 2.4 GHz interfaces bitrates to G standard and higher, removing all legacy stuff. It seems it worked. But with an upgrade to the new firmware image, this script started misbehaving and high-end WiFi devices were able to connect only with MSC 0. I determined that the issue is in the following command: iw wlan0 set bitrates legacy-2.4 6 9 12 18 24 36 48 54 ht-mcs-2.4 lgi-2.4 With this command in effect, my client has in station dump the following bitrates: tx bitrate: 6.5 MBit/s MCS 0 rx bitrate: 216.7 MBit/s MCS 23 short GI If I change the command to: iw wlan0 set bitrates legacy-2.4 6 9 12 18 24 36 48 54 tx bitrate: 195.0 MBit/s MCS 23 rx bitrate: 216.7 MBit/s MCS 23 short GI Which is the expected bitrate. If I run only: iw wlan0 set bitrates ht-mcs-2.4 tx bitrate: 11.0 MBit/s rx bitrate: 117.0 MBit/s MCS 20 This goes against the documentation which is saying that this should reset bitrates masks to normal: https://wireless.wiki.kernel.org/en/users/documentation/iw#modifying_tx_ht_mcs_bitrates Maybe I am not using the command correctly. In general it is unclear what should be correct behavior here. I also opened a SuperUser question: http://superuser.com/questions/881025/limiting-low-bitrates-with-iw-on-ath9k So maybe clearer documentation would make it easier to know what is the correct command? So, what is current (and hopefully future proof) command to not allow legacy bitrates, but to allow any other (which would work also on future devices without having to modify the list of allowed MCS when they are added)? iw --version iw version 3.15 kmod-ath - 3.10.49+2014-05-22-1 kmod-ath9k - 3.10.49+2014-05-22-1 kmod-ath9k-common - 3.10.49+2014-05-22-1 kmod-cfg80211 - 3.10.49+2014-05-22-1 kmod-mac80211 - 3.10.49+2014-05-22-1 wireless-info - 0.1-1 wireless-tools - 29-5 Mitar -- http://mitar.tnode.com/ https://twitter.com/mitar_m -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
