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Date:   Fri, 26 Aug 2022 15:05:51 -0700
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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:     Michael Wu <michael@allwinnertech.com>, jejb@linux.ibm.com,
        martin.petersen@oracle.com
Cc:     linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org
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From:   Bart Van Assche <bvanassche@acm.org>
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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.