Return-path: Received: from cora.hrz.tu-chemnitz.de ([134.109.228.40]:55824 "EHLO cora.hrz.tu-chemnitz.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935919Ab3DHUna (ORCPT ); Mon, 8 Apr 2013 16:43:30 -0400 From: Simon Wunderlich To: linux-wireless@vger.kernel.org Cc: zefir.kurtisi@neratec.com, mathias.kretschmer@fokus.fraunhofer.de, ordex@autistici.org, Simon Wunderlich Subject: [PATCHv4] mac80211: fix recalc_radar hwconf sync problem Date: Mon, 8 Apr 2013 22:43:16 +0200 Message-Id: <1365453796-17572-1-git-send-email-siwu@hrz.tu-chemnitz.de> (sfid-20130408_224347_713775_388BD8E8) In-Reply-To: <20130408175352.GC5938@ritirata.org> References: <20130408175352.GC5938@ritirata.org> Sender: linux-wireless-owner@vger.kernel.org List-ID: local->hw.conf maybe not be synced when recalcing whether radar is enabled, sometimes leaving radar enabled even if it's not neccesary anymore. Fix this by: * setting radar_enabled when creating the chanctx * turning radar_enabled off before destroying the last channel context Reported-by: Zefir Kurtisi Signed-off-by: Simon Wunderlich --- Changes to PATCHv3: * fix typo * move whole check into WARN_ON Changes to PATCHv2: * add comment about single context, and check for it * rebase on mac80211-next --- net/mac80211/chan.c | 43 +++++++++++++++++++++++++++++++++---------- 1 file changed, 33 insertions(+), 10 deletions(-) diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c index 8024874..166165e 100644 --- a/net/mac80211/chan.c +++ b/net/mac80211/chan.c @@ -57,6 +57,22 @@ ieee80211_find_chanctx(struct ieee80211_local *local, return NULL; } +static bool ieee80211_is_radar_required(struct ieee80211_local *local) +{ + struct ieee80211_sub_if_data *sdata; + + rcu_read_lock(); + list_for_each_entry_rcu(sdata, &local->interfaces, list) { + if (sdata->radar_required) { + rcu_read_unlock(); + return true; + } + } + rcu_read_unlock(); + + return false; +} + static struct ieee80211_chanctx * ieee80211_new_chanctx(struct ieee80211_local *local, const struct cfg80211_chan_def *chandef, @@ -75,6 +91,9 @@ ieee80211_new_chanctx(struct ieee80211_local *local, ctx->conf.rx_chains_static = 1; ctx->conf.rx_chains_dynamic = 1; ctx->mode = mode; + ctx->conf.radar_enabled = ieee80211_is_radar_required(local); + if (!local->use_chanctx) + local->hw.conf.radar_enabled = ctx->conf.radar_enabled; if (!local->use_chanctx) { local->_oper_chandef = *chandef; @@ -99,6 +118,7 @@ ieee80211_new_chanctx(struct ieee80211_local *local, static void ieee80211_free_chanctx(struct ieee80211_local *local, struct ieee80211_chanctx *ctx) { + bool check_single_channel = false; lockdep_assert_held(&local->chanctx_mtx); WARN_ON_ONCE(ctx->refcount != 0); @@ -108,6 +128,14 @@ static void ieee80211_free_chanctx(struct ieee80211_local *local, chandef->width = NL80211_CHAN_WIDTH_20_NOHT; chandef->center_freq1 = chandef->chan->center_freq; chandef->center_freq2 = 0; + + /* NOTE: Disabling radar is only valid here for + * single channel context. To be sure, check it ... + */ + if (local->hw.conf.radar_enabled) + check_single_channel = true; + local->hw.conf.radar_enabled = false; + ieee80211_hw_config(local, 0); } else { drv_remove_chanctx(local, ctx); @@ -116,6 +144,9 @@ static void ieee80211_free_chanctx(struct ieee80211_local *local, list_del_rcu(&ctx->list); kfree_rcu(ctx, rcu_head); + /* throw a warning if this wasn't the only channel context. */ + WARN_ON(check_single_channel && !list_empty(&local->chanctx_list)); + mutex_lock(&local->mtx); ieee80211_recalc_idle(local); mutex_unlock(&local->mtx); @@ -227,19 +258,11 @@ static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata) void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local, struct ieee80211_chanctx *chanctx) { - struct ieee80211_sub_if_data *sdata; - bool radar_enabled = false; + bool radar_enabled; lockdep_assert_held(&local->chanctx_mtx); - rcu_read_lock(); - list_for_each_entry_rcu(sdata, &local->interfaces, list) { - if (sdata->radar_required) { - radar_enabled = true; - break; - } - } - rcu_read_unlock(); + radar_enabled = ieee80211_is_radar_required(local); if (radar_enabled == chanctx->conf.radar_enabled) return; -- 1.7.10.4