Message-ID: <3a4fc4398a5dfe03933de8d695a8b605d700a94b.camel@sipsolutions.net>
Subject: Re: [PATCH] mac80211: disable BSS color collision detection in case
 of no free colors
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Rameshkumar Sundaram <quic_ramess@quicinc.com>
Cc:     linux-wireless@vger.kernel.org,
        Lavanya Suresh <lavaks@codeaurora.org>
Date:   Fri, 03 Dec 2021 09:08:32 +0100
In-Reply-To: <1638506507-21139-1-git-send-email-quic_ramess@quicinc.com>
References: <1638506507-21139-1-git-send-email-quic_ramess@quicinc.com>
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On Fri, 2021-12-03 at 10:11 +0530, Rameshkumar Sundaram wrote:
> 
> +++ b/net/mac80211/cfg.c
> @@ -995,6 +995,8 @@ static int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
>  	struct beacon_data *new, *old;
>  	int new_head_len, new_tail_len;
>  	int size, err;
> +	const u8 *cap;
> +	struct ieee80211_he_operation *he_oper = NULL;
>  	u32 changed = BSS_CHANGED_BEACON;
>  
>  	old = sdata_dereference(sdata->u.ap.beacon, sdata);
> @@ -1082,6 +1084,27 @@ static int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
>  		changed |= BSS_CHANGED_FTM_RESPONDER;
>  	}
>  
> +	if (sdata->vif.bss_conf.he_support) {
> +		cap = cfg80211_find_ext_ie(WLAN_EID_EXT_HE_OPERATION,
> +					   params->tail, params->tail_len);
> +		if (cap && cap[1] >= sizeof(*he_oper) + 1)
> +			he_oper = (void *)(cap + 3);
> 

I'm not sure I like this mechanism - in ieee80211_start_ap() we
explicitly take it from the parameters given via nl80211, so it feels
the same should be true here. Why isn't it done that way?

(And if we decide it should be this way then you should be using a new
"const struct element *cap" instead of "const u8 *cap", with the better
helpers functions etc.)

johannes