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Date:   Mon, 13 Apr 2020 16:11:41 +0530
From:   Sathishkumar Muruganandam <murugana@codeaurora.org>
To:     Johannes Berg <johannes@sipsolutions.net>, shaul.triebitz@intel.com
Cc:     'Luca Coelho' <luciano.coelho@intel.com>,
        linux-wireless@vger.kernel.org
Subject: Re: 4addr NDP in HE mode
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On 2020-03-20 18:28, Johannes Berg wrote:
> On Tue, 2020-02-18 at 11:39 +0530, Sathishkumar Muruganandam wrote:
> 
>> Since ieee80211_send_4addr_nullfunc() is only called for successful
>> association of 4addr STA, shall we allow below case alone for HE ?
>> 
>> static bool ieee80211_assoc_success(struct ieee80211_sub_if_data 
>> *sdata,
>>                                     struct cfg80211_bss *cbss,
>>                                     struct ieee80211_mgmt *mgmt, 
>> size_t len,
>>                                     struct ieee802_11_elems *elems)
>> {
>> ..
>>   /*
>>          * If we're using 4-addr mode, let the AP know that we're
>>          * doing so, so that it can create the STA VLAN on its side
>>          */
>>         if (ifmgd->use_4addr)
>>                 ieee80211_send_4addr_nullfunc(local, sdata);
>> ..
>> 
>> Whether this 4addr NDP in HE mode will affect any UL-MIMO from the 
>> 4addr STA
>> ? Please comment.
> 
> Off the top of my head, I don't know. Adding Shaul who might have an
> idea.
> 
> Shaul, basically the NDP is used here to initialize the 4-addr
> connection as such, and if the connection is HE capable we drop it. Can
> you remind me what exactly the issue with NDP in HE was, and do you 
> know
> how that'd be affected by 4-addr NDPs?
> 

Shaul, awaiting your response !

Thanks,
Sathishkumar