From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hans de Goede <j.w.r.degoede@hhs.nl>
Subject: Re: Linux scsi / usb-mass-storage and HP printer cardreader bug +
 fix
Date: Fri, 11 Jan 2008 13:48:31 +0100
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To: Boaz Harrosh <bharrosh@panasas.com>
Cc: USB Storage list <usb-storage@lists.one-eyed-alien.net>, fedora-kernel-list@redhat.com, USB development list <linux-usb-devel@lists.sourceforge.net>, David Brown <usb-storage2@davidb.org>, Guillaume Bedot <littletux@zarb.org>, linux-scsi@vger.kernel.org, linux-usb@vger.kernel.org

Boaz Harrosh wrote:
> On Thu, Jan 10 2008 at 12:52 +0200, Hans de Goede <j.w.r.degoede@hhs.nl> wrote:
>>> I'm not sure what the proper solution should be?
>>>
>> I guess the proper solution would be to add a special case to the scsi layer 
>> where the read10 / write10 command is issued, and split the request in 2 there 
>> when it involves the last sector.
>>
>> There was another reply in this thread stating that problems reading the last 
>> sector with sd / mmc cards happen quite often, and that this is most likely not 
>> an isolated case.
>>
>> Regards,
>>
>> Hans
> 
> Yes, you're right. in ULDs it is a much proper way to do this.
> 
> So I guess you'll have to do that special host flag or device
> flag, and add a check for it in sd.c. You'll see that sd.c is 
> already doing bufflen truncation at sd_prep_fn(), just add one
> more case.
> 

Yes,

That will work nicely, I'll write an updated patch this evening (when I have 
access to the printer to test again).

Regards,

Hans