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Message-ID: <4c2ad5e4a9747c59a55d92a8fa0c95df5821188f.camel@mediatek.com>
Subject: Re: [PATCH] r8152: stop submitting rx for -EPROTO
From:   Jason-ch Chen <jason-ch.chen@mediatek.com>
To:     Hayes Wang <hayeswang@realtek.com>,
        "matthias.bgg@gmail.com" <matthias.bgg@gmail.com>
CC:     "linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-arm-kernel@lists.infradead.org" 
        <linux-arm-kernel@lists.infradead.org>,
        "linux-mediatek@lists.infradead.org" 
        <linux-mediatek@lists.infradead.org>,
        "Project_Global_Chrome_Upstream_Group@mediatek.com" 
        <Project_Global_Chrome_Upstream_Group@mediatek.com>,
        "hsinyi@google.com" <hsinyi@google.com>,
        nic_swsd <nic_swsd@realtek.com>
Date:   Wed, 29 Sep 2021 17:52:37 +0800
In-Reply-To: <cbd1591fc03f480c9f08cc55585e2e35@realtek.com>
References: <20210929051812.3107-1-jason-ch.chen@mediatek.com>
         <cbd1591fc03f480c9f08cc55585e2e35@realtek.com>
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On Wed, 2021-09-29 at 08:14 +0000, Hayes Wang wrote:
> Jason-ch Chen <jason-ch.chen@mediatek.com>
> > Sent: Wednesday, September 29, 2021 1:18 PM
> 
> [...]
> > When unplugging RTL8152 Fast Ethernet Adapter which is plugged
> > into an USB HUB, the driver would get -EPROTO for bulk transfer.
> > There is a high probability to get the soft/hard lockup
> > information if the driver continues to submit Rx before the HUB
> > completes the detection of all hub ports and issue the
> > disconnect event.
> 
> I don't think it is a good idea.
> For the other situations which return the same error code, you would
> stop the rx, too.
> However, the rx may re-work after being resubmitted for the other
> cases.
> 
> Best Regards,
> Hayes
> 
Hi Hayes,

Sometimes Rx submits rapidly and the USB kernel driver of opensource
cannot receive any disconnect event due to CPU heavy loading, which
finally causes a system crash.
Do you have any suggestions to modify the r8152 driver to prevent this
situation happened?

Regards,
Jason