From mboxrd@z Thu Jan  1 00:00:00 1970
From: Florian Fainelli <f.fainelli@gmail.com>
Subject: Re: pegged softirq and NAPI race (?)
Date: Tue, 18 Sep 2018 14:35:46 -0700
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Cc: songliubraving@fb.com, Alexei Starovoitov <ast@fb.com>,
        netdev <netdev@vger.kernel.org>,
        Jeff Kirsher <jeffrey.t.kirsher@intel.com>,
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To: Eric Dumazet <edumazet@google.com>
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On 09/18/2018 02:28 PM, Eric Dumazet wrote:
> On Tue, Sep 18, 2018 at 2:25 PM Florian Fainelli <f.fainelli@gmail.com> wrote:
>>
>>
>> This would not be the only driver doing this unfortunately... should we
>> add a __must_check annotation to help catch those (mis)uses? Though that
>> could cause false positives for drivers using NAPI to clean their TX ring.
>>
> 
> Well, before adding __must_check we would need to cook a (big) patch
> series to change all occurrences.
> 

Sounds good, I don't mind submitting something unless you beat me to it.

> 
> Not clear why netpoll is the trigger ?
> 

Me either, this should be observable during normal operation as well,
though most likely you just get a spurious interrupt and nothing to
clean in the RX ring, so things just get unnoticed?
-- 
Florian