On Tue, Jun 25, 2024 at 08:26:59AM +0200, Hannes Reinecke wrote:
> On 6/25/24 00:12, 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.
> >
> > For ATA errors and ATA PASS-THROUGH commands the ATA_QCFLAG_RTF_FILLED
> > flag should be always set. Added WARN_ON_ONCE() checks to generate
> > a warning when ATA_QCFLAG_RTF_FILLED is not set and libata needs to
> > generate sense data.
> >
> > Signed-off-by: Igor Pylypiv <ipylypiv@xxxxxxxxxx>
> > ---
> > drivers/ata/libata-scsi.c | 10 ++++++++++
> > 1 file changed, 10 insertions(+)
> >
> > diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
> > index e5669a296d81..7a8a08692ce9 100644
> > --- a/drivers/ata/libata-scsi.c
> > +++ b/drivers/ata/libata-scsi.c
> > @@ -246,6 +246,9 @@ static void ata_scsi_set_passthru_sense_fields(struct ata_queued_cmd *qc)
> > struct ata_taskfile *tf = &qc->result_tf;
> > unsigned char *sb = cmd->sense_buffer;
> >
> > + if (WARN_ON_ONCE(!(qc->flags & ATA_QCFLAG_RTF_FILLED)))
> > + return;
> > +
> > if ((sb[0] & 0x7f) >= 0x72) {
> > unsigned char *desc;
> > u8 len;
> > @@ -928,6 +931,9 @@ static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
> > unsigned char *sb = cmd->sense_buffer;
> > u8 sense_key, asc, ascq;
> > + if (WARN_ON_ONCE(!(qc->flags & ATA_QCFLAG_RTF_FILLED)))
> > + return;
> > +
> > /*
> > * Use ata_to_sense_error() to map status register bits
> > * onto sense key, asc & ascq.
> > @@ -971,6 +977,10 @@ static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
> > ata_scsi_set_sense(dev, cmd, NOT_READY, 0x04, 0x21);
> > return;
> > }
> > +
> > + if (WARN_ON_ONCE(!(qc->flags & ATA_QCFLAG_RTF_FILLED)))
> > + return;
> > +
> > /* Use ata_to_sense_error() to map status register bits
> > * onto sense key, asc & ascq.
> > */
>
> Hmm. Not sure if we really need the WARN_ON() here or whether a simple
> logging message wouldn't be sufficient; after all, we continue fine here.
>
My worry about adding a simple log statement is that it might cause a log
spam if things go wrong for some reason.
This code is more like a "this should never happen" comment and we always
expect ATA_QCFLAG_RTF_FILLED to be present when generating sense data
based on ATA registers.
If WARN_ON_ONCE() is too much for this case I guess we can just remove it
and silently return?
Damien, Niklas, what are your thoughts on this?
Thanks,
Igor
> Cheers,
>
> Hannes
> --
> Dr. Hannes Reinecke Kernel Storage Architect
> hare@xxxxxxx +49 911 74053 688
> SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
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>
