From 104f5a6206f4b3133c675e3d41eca2ca4c41406b Mon Sep 17 00:00:00 2001 From: Eliad Peller Date: Sun, 8 Feb 2015 12:36:07 +0200 Subject: mac80211: clear sdata->radar_required If ieee80211_vif_use_channel() fails, we have to clear sdata->radar_required (which we might have just set). Failing to do it results in stale radar_required field which prevents starting new scan requests. Reported-by: Jouni Malinen Signed-off-by: Eliad Peller [use false instead of 0] Signed-off-by: Johannes Berg --- net/mac80211/chan.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'net/mac80211') diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c index ff0d2db09df9..5bcd4e5589d3 100644 --- a/net/mac80211/chan.c +++ b/net/mac80211/chan.c @@ -1508,6 +1508,8 @@ static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata) if (ieee80211_chanctx_refcount(local, ctx) == 0) ieee80211_free_chanctx(local, ctx); + sdata->radar_required = false; + /* Unreserving may ready an in-place reservation. */ if (use_reserved_switch) ieee80211_vif_use_reserved_switch(local); @@ -1566,6 +1568,9 @@ int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata, ieee80211_recalc_smps_chanctx(local, ctx); ieee80211_recalc_radar_chanctx(local, ctx); out: + if (ret) + sdata->radar_required = false; + mutex_unlock(&local->chanctx_mtx); return ret; } -- cgit v1.2.3 From 17dce15801d5602719936045a7e84ff7dc6b6da2 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Thu, 19 Feb 2015 12:57:40 +0100 Subject: mac80211/minstrel: fix !x!=0 confusion Commit 06d961a8e210 ("mac80211/minstrel: use the new rate control API") inverted the condition 'if (msr->sample_limit != 0)' to 'if (!msr->sample_limit != 0)'. But it is confusing both to people and compilers (gcc5): net/mac80211/rc80211_minstrel.c: In function 'minstrel_get_rate': net/mac80211/rc80211_minstrel.c:376:26: warning: logical not is only applied to the left hand side of comparison if (!msr->sample_limit != 0) ^ Let there be only 'if (!msr->sample_limit)'. Fixes: 06d961a8e210 ("mac80211/minstrel: use the new rate control API") Signed-off-by: Jiri Slaby Signed-off-by: Johannes Berg --- net/mac80211/rc80211_minstrel.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/mac80211') diff --git a/net/mac80211/rc80211_minstrel.c b/net/mac80211/rc80211_minstrel.c index 7c86a002df95..ef6e8a6c4253 100644 --- a/net/mac80211/rc80211_minstrel.c +++ b/net/mac80211/rc80211_minstrel.c @@ -373,7 +373,7 @@ minstrel_get_rate(void *priv, struct ieee80211_sta *sta, rate++; mi->sample_deferred++; } else { - if (!msr->sample_limit != 0) + if (!msr->sample_limit) return; mi->sample_packets++; -- cgit v1.2.3 From 9c1c98a3bb7b7593b60264b9a07e001e68b46697 Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Thu, 26 Feb 2015 15:50:50 +0200 Subject: mac80211: Send EAPOL frames at lowest rate The current minstrel_ht rate control behavior is somewhat optimistic in trying to find optimum TX rate. While this is usually fine for normal Data frames, there are cases where a more conservative set of retry parameters would be beneficial to make the connection more robust. EAPOL frames are critical to the authentication and especially the EAPOL-Key message 4/4 (the last message in the 4-way handshake) is important to get through to the AP. If that message is lost, the only recovery mechanism in many cases is to reassociate with the AP and start from scratch. This can often be avoided by trying to send the frame with more conservative rate and/or with more link layer retries. In most cases, minstrel_ht is currently using the initial EAPOL-Key frames for probing higher rates and this results in only five link layer transmission attempts (one at high(ish) MCS and four at MCS0). While this works with most APs, it looks like there are some deployed APs that may have issues with the EAPOL frames using HT MCS immediately after association. Similarly, there may be issues in cases where the signal strength or radio environment is not good enough to be able to get frames through even at couple of MCS 0 tries. The best approach for this would likely to be to reduce the TX rate for the last rate (3rd rate parameter in the set) to a low basic rate (say, 6 Mbps on 5 GHz and 2 or 5.5 Mbps on 2.4 GHz), but doing that cleanly requires some more effort. For now, we can start with a simple one-liner that forces the minimum rate to be used for EAPOL frames similarly how the TX rate is selected for the IEEE 802.11 Management frames. This does result in a small extra latency added to the cases where the AP would be able to receive the higher rate, but taken into account how small number of EAPOL frames are used, this is likely to be insignificant. A future optimization in the minstrel_ht design can also allow this patch to be reverted to get back to the more optimized initial TX rate. It should also be noted that many drivers that do not use minstrel as the rate control algorithm are already doing similar workarounds by forcing the lowest TX rate to be used for EAPOL frames. Cc: stable@vger.kernel.org Reported-by: Linus Torvalds Tested-by: Linus Torvalds Signed-off-by: Jouni Malinen Signed-off-by: Johannes Berg --- net/mac80211/tx.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net/mac80211') diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 88a18ffe2975..07bd8db00af8 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -566,6 +566,7 @@ ieee80211_tx_h_check_control_port_protocol(struct ieee80211_tx_data *tx) if (tx->sdata->control_port_no_encrypt) info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; info->control.flags |= IEEE80211_TX_CTRL_PORT_CTRL_PROTO; + info->flags |= IEEE80211_TX_CTL_USE_MINRATE; } return TX_CONTINUE; -- cgit v1.2.3