From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jon Hunter <jonathanh@nvidia.com>
Subject: Re: [PATCH net-next 3/3] net: stmmac: Convert to phylink and remove
 phylib logic
Date: Tue, 18 Jun 2019 20:44:10 +0100
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 <26cfaeff-a310-3b79-5b57-fd9c93bd8929@nvidia.com>
 <78EB27739596EE489E55E81C33FEC33A0B9C8DD9@DE02WEMBXB.internal.synopsys.com>
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To: Jose Abreu <Jose.Abreu@synopsys.com>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, "netdev@vger.kernel.org" <netdev@vger.kernel.org>
Cc: Joao Pinto <Joao.Pinto@synopsys.com>, "David S . Miller" <davem@davemloft.net>, Giuseppe Cavallaro <peppe.cavallaro@st.com>, Alexandre Torgue <alexandre.torgue@st.com>, Russell King <linux@armlinux.org.uk>, Andrew Lunn <andrew@lunn.ch>, Florian Fainelli <f.fainelli@gmail.com>, Heiner Kallweit <hkallweit1@gmail.com>, linux-tegra <linux-tegra@vger.kernel.org>
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On 18/06/2019 16:20, Jon Hunter wrote:
> 
> On 18/06/2019 11:18, Jon Hunter wrote:
>>
>> On 18/06/2019 10:46, Jose Abreu wrote:
>>> From: Jon Hunter <jonathanh@nvidia.com>
>>>
>>>> I am not certain but I don't believe so. We are using a static IP address
>>>> and mounting the root file-system via NFS when we see this ...
>>>
>>> Can you please add a call to napi_synchronize() before every 
>>> napi_disable() calls, like this:
>>>
>>> if (queue < rx_queues_cnt) {
>>> 	napi_synchronize(&ch->rx_napi);
>>> 	napi_disable(&ch->rx_napi);
>>> }
>>>
>>> if (queue < tx_queues_cnt) {
>>> 	napi_synchronize(&ch->tx_napi);
>>> 	napi_disable(&ch->tx_napi);
>>> }
>>>
>>> [ I can send you a patch if you prefer ]
>>
>> Yes I can try this and for completeness you mean ...
>>
>> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>> index 4ca46289a742..d4a12cb64d8e 100644
>> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>> @@ -146,10 +146,15 @@ static void stmmac_disable_all_queues(struct stmmac_priv *priv)
>>         for (queue = 0; queue < maxq; queue++) {
>>                 struct stmmac_channel *ch = &priv->channel[queue];
>>  
>> -               if (queue < rx_queues_cnt)
>> +               if (queue < rx_queues_cnt) {
>> +                       napi_synchronize(&ch->rx_napi);
>>                         napi_disable(&ch->rx_napi);
>> -               if (queue < tx_queues_cnt)
>> +               }
>> +
>> +               if (queue < tx_queues_cnt) {
>> +                       napi_synchronize(&ch->tx_napi);
>>                         napi_disable(&ch->tx_napi);
>> +               }
>>         }
>>  }
> 
> So good news and bad news ...
> 
> The good news is that the above change does fix the initial crash
> I am seeing. However, even with this change applied on top of
> -next, it is still dying somewhere else and so there appears to
> be a second issue. 

Further testing has shown that actually this does NOT resolve the issue
and I am still seeing the crash. Sorry for the false-positive.

Jon

-- 
nvpublic