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Subject: Re: [PATCH] mac80211: fix possible deadlock in TX path
To:     =?UTF-8?Q?Toke_H=c3=b8iland-J=c3=b8rgensen?= <toke@redhat.com>,
        johannes@sipsolutions.net, davem@davemloft.net,
        linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20190427204155.14211-1-erik.stromdahl@gmail.com>
 <87k1fcnd9y.fsf@toke.dk>
From:   Erik Stromdahl <erik.stromdahl@gmail.com>
Message-ID: <656f3938-ef82-c1ce-753c-cb6b9d3c424b@gmail.com>
Date:   Wed, 1 May 2019 13:06:47 +0200
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On 4/30/19 9:49 AM, Toke Høiland-Jørgensen wrote:
> Erik Stromdahl <erik.stromdahl@gmail.com> writes:
> 
>> This patch fixes a possible deadlock when updating the TX statistics
>> (when calling into ieee80211_tx_stats()) from ieee80211_tx_dequeue().
> 
> So is this the fix for the issue with TX scheduling you reported
> earlier? :)
> 

Actually not. I thought so initially, but then, after a few more test runs,
I was able to run into the issue again.

But it does seem to fix the other issue with the RCU stall since I haven't
seen it with this patch applied (could be just a coincidence though).

--
Erik