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Date:   Thu, 22 Jun 2023 18:25:18 +0200
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To:     Johannes Berg <johannes@sipsolutions.net>,
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From:   Felix Fietkau <nbd@nbd.name>
Subject: Re: [PATCH] cfg80211: fix sband iftype data lookup for AP_VLAN
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On 22.06.23 18:07, Johannes Berg wrote:
> On Thu, 2023-06-22 at 18:05 +0200, Felix Fietkau wrote:
>> Since AP_VLAN interfaces are not pushed to the driver, 
>> 
> That's a mac80211 thing though.
> 
>> the driver should not
>> be expected to register iftype data for them.
>> Map them to the regular AP iftype on lookup.
> 
> And this is in cfg80211 - not sure that seems right?
> 
> OTOH I'd expect no callers with VLAN here, it doesn't really make sense
> since they're not a standalone mode that actually has HE/EHT, but still,
> seems odd this way?
> 
> What's actually calling it? I'm guessing somewhere in mac80211?

Yes, I guess only mac80211 is affected. I put in the cfg80211 prefix
because that's what the header file belongs to.

I made the patch in response to this:
https://patchwork.kernel.org/project/linux-wireless/patch/20230605152141.17434-4-shayne.chen@mediatek.com/

I found that there are several calls to ieee80211_get_he_iftype_cap and
ieee80211_get_eht_iftype_cap, which could be affected by this issue.
I thought dealing with this in a single place would be better than playing
whac-a-mole by fixing it at the call sites.

- Felix