Re: [REGRESSION] 28676d869bbb (scsi: sg: check for valid direction before starting the request) breaks mtx tape library control

Johannes Thumshirn
2017-07-18T07:37:51Z

On Mon, Jul 17, 2017 at 07:44:50PM -0500, Jason L Tibbitts III wrote:
> and confirmed that clean unpatched 4.12 shows the problem, while
> reverting just that patch fixes the issue. Unfortunately I don't know
> enough to actually fix this, but I can easily test patches.

This is fixed with:
commit 68c59fcea1f2c6a54c62aa896cc623c1b5bc9b47
Author: Johannes Thumshirn <jthumshirn@suse.de>
Date: Fri Jul 7 10:56:38 2017 +0200

scsi: sg: fix SG_DXFER_FROM_DEV transfers

SG_DXFER_FROM_DEV transfers do not necessarily have a dxferp as we set
it to NULL for the old sg_io read/write interface, but must have a
length bigger than 0. This fixes a regression introduced by commit
28676d869bbb ("scsi: sg: check for valid direction before starting the
request")

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Fixes: 28676d869bbb ("scsi: sg: check for valid direction before starting the request")
Reported-by: Chris Clayton <chris2553@googlemail.com>
Tested-by: Chris Clayton <chris2553@googlemail.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Chris Clayton <chris2553@googlemail.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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