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Message-ID: <86a49e1c-6ed3-f8f4-6f83-0bb90dbc99bb@nvidia.com>
Date:   Thu, 7 Jul 2022 11:12:26 +0100
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Subject: Re: [PATCH] net: stmmac: dwc-qos: Disable split header for Tegra194
Content-Language: en-US
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     Giuseppe Cavallaro <peppe.cavallaro@st.com>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Jose Abreu <joabreu@synopsys.com>,
        "David S . Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-tegra@vger.kernel.org
References: <20220706083913.13750-1-jonathanh@nvidia.com>
 <20220706191140.5a0f4337@kernel.org>
From:   Jon Hunter <jonathanh@nvidia.com>
In-Reply-To: <20220706191140.5a0f4337@kernel.org>
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On 07/07/2022 03:11, Jakub Kicinski wrote:
> On Wed, 6 Jul 2022 09:39:13 +0100 Jon Hunter wrote:
>> There is a long-standing issue with the Synopsys DWC Ethernet driver
>> for Tegra194 where random system crashes have been observed [0]. The
>> problem occurs when the split header feature is enabled in the stmmac
>> driver. In the bad case, a larger than expected buffer length is
>> received and causes the calculation of the total buffer length to
>> overflow. This results in a very large buffer length that causes the
>> kernel to crash. Why this larger buffer length is received is not clear,
>> however, the feedback from the NVIDIA design team is that the split
>> header feature is not supported for Tegra194. Therefore, disable split
>> header support for Tegra194 to prevent these random crashes from
>> occurring.
>>
>> [0] https://lore.kernel.org/linux-tegra/b0b17697-f23e-8fa5-3757-604a86f3a095@nvidia.com/
>>
>> Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
> 
> Fixes: 67afd6d1cfdf ("net: stmmac: Add Split Header support and enable it in XGMAC cores")
> 
> correct?


Yes that is correct. I forgot to add. Let me know if you want me to send 
a V2.

Thanks
Jon

-- 
nvpublic