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Date:   Mon, 29 Aug 2022 17:06:44 +0800
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Subject: Re: [PATCH] scsi: core: Fix block I/O error of USB card reader during
 resume
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To:     Bart Van Assche <bvanassche@acm.org>, jejb@linux.ibm.com,
        martin.petersen@oracle.com
Cc:     linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20220817083438.118293-1-michael@allwinnertech.com>
 <ceba3c96-5f32-9b5a-bacc-0eb942b9b90b@acm.org>
 <6412c518-426a-69a4-e419-83dc97bebe27@allwinnertech.com>
 <5ba28a61-0aa2-14d7-61f0-0e9316844f70@acm.org>
From:   Michael Wu <michael@allwinnertech.com>
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On 8/27/2022 6:05 AM, Bart Van Assche wrote:
> On 8/23/22 03:16, Michael Wu wrote:
>> Yes... My patch did seem suspicious. Here's the scene about the block 
>> I/O error: Some card reader does not respond the command 'MEDIUM 
>> REMOVAL PREVENT' correctly, as a result, the host does not send 
>> subsequent cmd 'MEDIUM REMOVAL ALLOW'/'MEDIUM REMOVAL PREVENT' 
>> before/after sleep, which leads to a enumeration failure after system 
>> resume.
>> I wonder, without changing the behavior of the device, is there's a 
>> better way to solve this? -- Modifying the scsi core should not be a 
>> good idea though :(
> 
> The above is not clear to me. My understanding is that "MEDIUM REMOVAL 
> PREVENT" is a sense code instead of a SCSI command?
> 
>> Thanks for your kindly notice. I looked around in the latest linux 
>> mainline repo, but could not find this code. Where can I get this 2002 
>> version of scsi_lib.c? Thank you.
> 
> Please take a look at 
> https://stackoverflow.com/questions/3264283/linux-kernel-historical-git-repository-with-full-history. 
> That web page has instructions for how to configure a git repository 
> such that history goes back before the time when Linus started using git.
> 
> Bart.
> 
Dear Bart,
Thank you. I'll try to figure it out and sync to you later.

-- 
Regards,
Michael Wu