Re: [PATCH v3 6/6] ata: libata-scsi: Check ATA_QCFLAG_RTF_FILLED before using result_tf

[Igor Pylypiv <ipylypiv@google.com>]

On Thu, Jun 27, 2024 at 09:19:17AM +0900, Damien Le Moal wrote:
> On 6/27/24 08:04, Igor Pylypiv wrote:
> > qc->result_tf contents are only valid when the ATA_QCFLAG_RTF_FILLED flag
> > is set. The ATA_QCFLAG_RTF_FILLED flag should be always set for commands
> > that failed or for commands that have the ATA_QCFLAG_RESULT_TF flag set.
> > 
> > Signed-off-by: Igor Pylypiv <ipylypiv@google.com>
> 
> Please change "RTF" to "result TF" in the messages below, to be clear (RTF is
> not). Feel free to split the ata_dev_dbg() lines after "dev," to avoid long lines.

Thanks Damien! I wrote "result taskfile" first, then changed it to "result TF",
and then to "RTF" to shorten the lines :)

I'll change it to "result TF" with the line split in v3.

> 
> With that:
> 
> Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
> 
> > ---
> >  drivers/ata/libata-scsi.c | 18 ++++++++++++++++++
> >  1 file changed, 18 insertions(+)
> > 
> > diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
> > index 02af4d5d5799..d5874d4b9253 100644
> > --- a/drivers/ata/libata-scsi.c
> > +++ b/drivers/ata/libata-scsi.c
> > @@ -242,10 +242,16 @@ void ata_scsi_set_sense_information(struct ata_device *dev,
> >   */
> >  static void ata_scsi_set_passthru_sense_fields(struct ata_queued_cmd *qc)
> >  {
> > +	struct ata_device *dev = qc->dev;
> >  	struct scsi_cmnd *cmd = qc->scsicmd;
> >  	struct ata_taskfile *tf = &qc->result_tf;
> >  	unsigned char *sb = cmd->sense_buffer;
> >  
> > +	if (!(qc->flags & ATA_QCFLAG_RTF_FILLED)) {
> > +		ata_dev_dbg(dev, "Missing RTF: cannot set ATA PT sense fields.\n");
> > +		return;
> > +	}
> > +
> >  	if ((sb[0] & 0x7f) >= 0x72) {
> >  		unsigned char *desc;
> >  		u8 len;
> > @@ -923,10 +929,16 @@ static void ata_to_sense_error(u8 drv_stat, u8 drv_err, u8 *sk, u8 *asc,
> >   */
> >  static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
> >  {
> > +	struct ata_device *dev = qc->dev;
> >  	struct scsi_cmnd *cmd = qc->scsicmd;
> >  	struct ata_taskfile *tf = &qc->result_tf;
> >  	u8 sense_key, asc, ascq;
> >  
> > +	if (!(qc->flags & ATA_QCFLAG_RTF_FILLED)) {
> > +		ata_dev_dbg(dev, "Missing RTF: cannot generate ATA PT sense data.\n");
> > +		return;
> > +	}
> > +
> >  	/*
> >  	 * Use ata_to_sense_error() to map status register bits
> >  	 * onto sense key, asc & ascq.
> > @@ -970,6 +982,12 @@ static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
> >  		ata_scsi_set_sense(dev, cmd, NOT_READY, 0x04, 0x21);
> >  		return;
> >  	}
> > +
> > +	if (!(qc->flags & ATA_QCFLAG_RTF_FILLED)) {
> > +		ata_dev_dbg(dev, "Missing RTF: cannot generate sense data.\n");
> > +		return;
> > +	}
> > +
> >  	/* Use ata_to_sense_error() to map status register bits
> >  	 * onto sense key, asc & ascq.
> >  	 */
> 
> -- 
> Damien Le Moal
> Western Digital Research
> 
Thanks,
Igor