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Date:   Tue, 28 Jul 2020 16:02:43 -0400
From:   Alan Stern <stern@rowland.harvard.edu>
To:     Martin Kepplinger <martin.kepplinger@puri.sm>
Cc:     Bart Van Assche <bvanassche@acm.org>, jejb@linux.ibm.com,
        Can Guo <cang@codeaurora.org>, martin.petersen@oracle.com,
        linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
        kernel@puri.sm
Subject: Re: [PATCH] scsi: sd: add runtime pm to open / release
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On Tue, Jul 28, 2020 at 09:02:44AM +0200, Martin Kepplinger wrote:
> Hi Alan,
> 
> Any API cleanup is of course welcome. I just wanted to remind you that
> the underlying problem: broken block device runtime pm. Your initial
> proposed fix "almost" did it and mounting works but during file access,
> it still just looks like a runtime_resume is missing somewhere.

Well, I have tested that proposed fix several times, and on my system 
it's working perfectly.  When I stop accessing a drive it autosuspends, 
and when I access it again it gets resumed and works -- as you would 
expect.

> As we need to have that working at some point, I might look into it, but
> someone who has experience in the block layer can surely do it more
> efficiently.

I suspect that any problems you still face are caused by something else.

Alan Stern