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From:   Adrian Chadd <adrian@freebsd.org>
Date:   Tue, 19 Jul 2022 08:03:21 -0700
Message-ID: <CAJ-VmomaQ-ai7n5i8-8sXsgaih4vjjHXyw+JQESGMERgC8Qqdw@mail.gmail.com>
Subject: Re: [PATCH] mac80211: Fix wrong channel bandwidths reported for aggregates
To:     =?UTF-8?Q?Linus_L=C3=BCssing?= <linus.luessing@c0d3.blue>
Cc:     Johannes Berg <johannes.berg@intel.com>,
        "David S . Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        =?UTF-8?B?VG9rZSBIw7hpbGFuZC1Kw7hyZ2Vuc2Vu?= <toke@toke.dk>,
        Kalle Valo <kvalo@kernel.org>, Felix Fietkau <nbd@nbd.name>,
        Simon Wunderlich <sw@simonwunderlich.de>,
        Sven Eckelmann <sven@narfation.org>,
        ath10k <ath10k@lists.infradead.org>,
        linux-wireless <linux-wireless@vger.kernel.org>,
        netdev <netdev@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        =?UTF-8?Q?Linus_L=C3=BCssing?= <ll@simonwunderlich.de>
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On Mon, 18 Jul 2022 at 15:28, Linus Lüssing <linus.luessing@c0d3.blue> wrote:
>
> From: Linus Lüssing <ll@simonwunderlich.de>
>
> AR9003 based wifi chips have a hardware bug, they always report a
> channel bandwidth of HT40 for any sub-frame of an aggregate which is
> not the last one. Only the last sub-frame has correct channel bandwidth
> information.

Hi!

It's not a hardware bug. Dating back to the original AR5416 11n chip,
most flags aren't valid for subframes in an aggregate. Only the final
frame has valid flags. This was explicitly covered internally way back
when.


-adrian