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Date:   Thu, 29 Sep 2022 19:11:37 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Kevin Mitchell <kevmitch@arista.com>
Cc:     Antoine Tenart <atenart@kernel.org>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: new warning caused by ("net-sysfs: update the queue counts in
 the unregistration path")
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On Wed, 28 Sep 2022 16:20:33 -0700 Kevin Mitchell wrote:
> > As you said and looking around queue 0 is somewhat special and used as a
> > fallback. My suggestion would be to 1) check if the above race is
> > expected 2) if yes, a possible solution would be not to warn when
> > real_num_tx_queues == 0 as in such cases selecting queue 0 would be the
> > expected fallback (and you might want to check places like [1]).  
> 
> Yes this is exactly where this is happening and that sounds like a good idea to
> me. As far as I can tell, the message is completely innocuous. If there really
> are no cases where it is useful to have this warning for real_num_tx_queues ==
> 0, I could submit a patch to not emit it in that case.

SGTM, FWIW.