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Date:   Thu, 18 Jan 2018 09:50:22 -0500 (EST)
Message-Id: <20180118.095022.1121845945987753430.davem@davemloft.net>
To:     hayeswang@realtek.com
Cc:     kai.heng.feng@canonical.com, gregkh@linuxfoundation.org,
        linux-usb@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, mario.limonciello@dell.com,
        nic_swsd@realtek.com
Subject: Re: [PATCH v2] r8152: disable RX aggregation on Dell TB16 dock
From:   David Miller <davem@davemloft.net>
In-Reply-To: <0835B3720019904CB8F7AA43166CEEB2D2E16D63@RTITMBSV06.realtek.com.tw>
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        <20180117.153930.330864749049561139.davem@davemloft.net>
        <0835B3720019904CB8F7AA43166CEEB2D2E16D63@RTITMBSV06.realtek.com.tw>
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From: Hayes Wang <hayeswang@realtek.com>
Date: Thu, 18 Jan 2018 03:04:08 +0000

> [...]
>> > r8153 on Dell TB15/16 dock corrupts rx packets.
>> >
>> > This change is suggested by Realtek. They guess that the XHCI
>> > controller doesn't have enough buffer, and their guesswork is correct,
>> > once the RX aggregation gets disabled, the issue is gone.
>> >
>> > ASMedia is currently working on a real sulotion for this issue.
>> >
>> > Dell and ODM confirm the bcdDevice and iSerialNumber is unique for TB16.
>> >
>> > Note that TB15 has different bcdDevice and iSerialNumber, which are
>> > not unique values. If you still have TB15, please contact Dell to
>> > replace it with TB16.
> 
> Excuse me. I don't understand why this patch is for specific USB nic rather than xHCI.
> It seems to make the specific USB nic working and the other ones keeping error.

Well, are we sure that the device being in the TB16 dock doesn't
contribute to the issue as well?

If the problem only shows up with XHCI and this dock, then this patch
was the appropriate way to deal with the problem for now.