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From:   Nick Morrow <morrownr@gmail.com>
Date:   Mon, 26 Dec 2022 17:26:20 -0600
Message-ID: <CAFktD2fbpUv9X5MY1jozyXoxvNXW=4OfaJ3B1KcZtdrBfiG4NA@mail.gmail.com>
Subject: Re: [bug report} wifi: mt76: mt7612u/mt7610u - 6.1.x hard locking systems
To:     Lorenzo Bianconi <lorenzo@kernel.org>
Cc:     nbd@nbd.name, ryder.lee@mediatek.com, shayne.chen@mediatek.com,
        Sean Wang <sean.wang@mediatek.com>, deren.wu@mediatek.com,
        linux-wireless@vger.kernel.org, linux-mediatek@lists.infradead.org
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> > Starting with kernel 6.1 rc1, mt7612u and mt7610u are hard locking
> > systems when connection is established. From a report this morning:
> >
> > "So I'm using a MT7610U based adapter and updated to 6.1.1 in Arch
> > Linux and it's a complete lockup a few seconds after connecting as
> > other people have said, I'll use the LTS kernel (5.15) in the
> > meanwhile but this is probably going to get a lot of people that use
> > distros with newer kernels."
> >
> > Background: Problem first discovered with kernel 6.1 rc1. Bug report
> > was seen on linux-wireless around the rc5 timeframe. This is an
> > additional bug report.
> >
> > I don't think additional info is needed as I have tested on several
> > distros with various RC's of 6.1 and the problem is 100% reproducible
> > and unavoidable. This is a show stopper bug and will result in
> > widespread reports as distros upgrade to kernel 6.1.
> >
> > Regards,
>
> Hi Nick,
>
> Can you please try the patch below?
> https://patchwork.kernel.org/project/linux-wireless/patch/20221217085624.52077-1-nbd@nbd.name/
>
> Regards,
> Lorenzo

Lorenzo,

Today, I downloaded kernel 6.1.1, applied the above patch and
compiled. Once installed, I tested with an Alfa ACM mt7612u based
adapter. I no longer see the problem. No system lockups at all. iperf3
is showing a consistent performance of around 387 Mb/s. dmesg is
clean. The patch appears to have fixed the issue. I can also test with
a mt7610u based adapter if you think it is necessary but since that
patch was not to mt76, I decided testing only with the mt7612u adapter
was probably good enough. Let me know if there is anything else I can
do.

Nick
https://github.com/morrownr/USB-WiFi