Re: [PATCH v3 1/6] ata: libata-scsi: Fix offsets for the fixed format sense data

[Niklas Cassel <cassel@kernel.org>]

On Fri, Jun 28, 2024 at 05:49:22PM +0200, Niklas Cassel wrote:
> On Fri, Jun 28, 2024 at 08:47:03AM +0200, Hannes Reinecke wrote:
> > On 6/27/24 14:08, Niklas Cassel wrote:
> 
> In SAT-6 there is no mention of compliance with ANSI INCITS 431-2007 should
> ignore D_SENSE bit and unconditionally return sense data in descriptor format.
> 
> Anyway, considering that:
> 1) I'm not sure how a SAT would expose that it is compliant with ANSI INCITS
>    431-2007.
> 2) This text has been removed from SAT-6.
> 3) We currently honour the D_SENSE bit when creating the sense buffer with the
>    SK/ASC/ASCQ that we get from the device.
> 
> I think that it makes sense to honour the D_SENSE bit also when generating
> sense data for successful ATA PASS-THROUGH commands (from ATA registers).

Igor, I think you should add a new patch in your series that does:

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index d5874d4b9253..5b211551ac10 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -949,11 +949,8 @@ static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
                                   &sense_key, &asc, &ascq);
                ata_scsi_set_sense(qc->dev, cmd, sense_key, asc, ascq);
        } else {
-               /*
-                * ATA PASS-THROUGH INFORMATION AVAILABLE
-                * Always in descriptor format sense.
-                */
-               scsi_build_sense(cmd, 1, RECOVERED_ERROR, 0, 0x1D);
+               /* ATA PASS-THROUGH INFORMATION AVAILABLE */
+               ata_scsi_set_sense(qc->dev, cmd, RECOVERED_ERROR, 0, 0x1D);
        }
 }


Feel free to copy my arguments above.

I also checked VPD page 89h (ATA Information VPD page), and there are
no bits there either to claim certain SAT version compliance.

And since this text is not in SAT-6, I can only imagine that they decided
that is was not a good idea to not always honor D_SENSE...

(It does seem simpler to just always honor it...)


Kind regards,
Niklas