Message-ID: <1396946168.5936.0.camel@jlt4.sipsolutions.net> (sfid-20140408_103629_220978_35F291B3)
Subject: Re: [PATCH] mac80211: fix radar_enabled propagation
From: Johannes Berg <johannes@sipsolutions.net>
To: Michal Kazior <michal.kazior@tieto.com>
Cc: linux-wireless@vger.kernel.org
Date: Tue, 08 Apr 2014 10:36:08 +0200
In-Reply-To: <1396609363-24539-1-git-send-email-michal.kazior@tieto.com> (sfid-20140404_130852_698229_A2912E57)
References: <1396609363-24539-1-git-send-email-michal.kazior@tieto.com>
	 (sfid-20140404_130852_698229_A2912E57)
Content-Type: text/plain; charset="UTF-8"
Mime-Version: 1.0
Sender: linux-wireless-owner@vger.kernel.org

On Fri, 2014-04-04 at 13:02 +0200, Michal Kazior wrote:
> If chandef had non-HT width it was possible for
> radar_enabled update to not be propagated properly
> through drv_config(). This happened because
> ieee80211_hw_conf_chan() would never see different
> local->hw.conf.chandef and local->_oper_chandef.
> 
> This wasn't a problem with HT chandefs because
> _oper_chandef width is reset to non-HT in
> ieee80211_free_chanctx() making
> ieee80211_hw_conf_chan() to kick in.
> 
> This problem led (at least) ath10k to not start
> CAC if prior CAC was cancelled and both CACs were
> requested for identical non-HT chandefs.
> 
> Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
> ---
>  net/mac80211/chan.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
> index 122033d..b472daa 100644
> --- a/net/mac80211/chan.c
> +++ b/net/mac80211/chan.c
> @@ -269,7 +269,7 @@ ieee80211_new_chanctx(struct ieee80211_local *local,
>  
>  	if (!local->use_chanctx) {
>  		local->_oper_chandef = *chandef;
> -		ieee80211_hw_config(local, 0);
> +		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);

I'm not convinced that this is the right way to do this - couldn't
ieee80211_hw_conf_chan() detect the radar detection requirement change?

johannes