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Message-ID: <6c2b5e49-2cdc-b506-e3c8-0a51fccc294d@quicinc.com>
Date:   Tue, 10 Jan 2023 15:23:19 +0800
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Subject: Re: [PATCH v10 3/5] cfg80211/mac80211: move interface counting for
 combination check to mac80211
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To:     Johannes Berg <johannes@sipsolutions.net>,
        Luciano Coelho <luciano.coelho@intel.com>,
        <linux-wireless@vger.kernel.org>
CC:     <michal.kazior@tieto.com>, <sw@simonwunderlich.de>,
        <andrei.otcheretianski@intel.com>, <eliad@wizery.com>,
        <ath11k@lists.infradead.org>
References: <1394547394-3910-1-git-send-email-luciano.coelho@intel.com>
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 <4de1f964-b623-2b31-c044-60cc188fc134@quicinc.com>
 <6187b1566674ba2e0d7d5413af5475688d8421b3.camel@sipsolutions.net>
From:   Wen Gong <quic_wgong@quicinc.com>
In-Reply-To: <6187b1566674ba2e0d7d5413af5475688d8421b3.camel@sipsolutions.net>
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On 1/9/2023 6:05 PM, Johannes Berg wrote:
> On Mon, 2023-01-09 at 17:39 +0800, Wen Gong wrote:
>> On 3/11/2014 10:16 PM, Luciano Coelho wrote:
>>> ...
>>> +int ieee80211_check_combinations(struct ieee80211_sub_if_data *sdata,
>>> +				 const struct cfg80211_chan_def *chandef,
>>> +				 enum ieee80211_chanctx_mode chanmode,
>>> +				 u8 radar_detect)
...
>>> +
>>> +	if (total == 1 && !radar_detect)
>>> +		return 0;
>>> +
>> should also check with cfg80211_check_combinations() when total == 1 and
>> num_different_channels > 1 ?
>>
>> When MLO is enabled, it could have 2 channels for one ieee80211_sub_if_data.
>>
> Heh. You're commenting on a patch from 2014, well before MLO :-)
>
> Not sure what happens in the code now?
>
> johannes
Yes, it is 2014. Each interface only has one channel at 2014.
I did not hit issue for the code.

the story is like this:
When station interface and p2p device interface both running.
the station connect to MLO AP which has 2 links.
The ieee80211_link_use_channel()/ieee80211_check_combinations() call 
cfg80211_check_combinations()
for the channel1 and channel2 because total==2.
When only station interface is running, not called for channel1/channel2 
because total==1.
That is the little thing I hit.