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Date:   Thu, 28 Apr 2022 06:06:28 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     Lin Ma <linma@zju.edu.cn>, Duoming Zhou <duoming@zju.edu.cn>,
        krzysztof.kozlowski@linaro.org, pabeni@redhat.com,
        linux-kernel@vger.kernel.org, davem@davemloft.net,
        alexander.deucher@amd.com, akpm@linux-foundation.org,
        broonie@kernel.org, netdev@vger.kernel.org
Subject: Re: [PATCH net v4] nfc: ... device_is_registered() is data
 race-able
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On Thu, 28 Apr 2022 11:20:16 +0200 Greg KH wrote:
> > The added dev_register variable can function like the original
> > device_is_registered and does not race-able because of the
> > protection of device_lock.  
> 
> Yes, that looks better, but what is the root problem here that you are
> trying to solve?  Why does NFC need this when no other subsystem does?

Yeah :( The NFC and NCI locking is shaky at best, grounds-up redesign
with clear rules would be great... but then again I'm not sure if anyone
is actually using this code IRL, so the motivation to invest time is
rather weak.