1. Patchew
  2. linux
  3. [PATCH v2 0/6] ATA PASS-THROUGH sense data fixes
  4. View patch

[PATCH v2 6/6] ata: libata-scsi: Check ATA_QCFLAG_RTF_FILLED before using result_tf

Igor Pylypiv posted 6 patches 1 year, 5 months ago
There is a newer version of this series
[PATCH v2 6/6] ata: libata-scsi: Check ATA_QCFLAG_RTF_FILLED before using result_tf
Posted by Igor Pylypiv 1 year, 5 months ago 
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@google.com>
---
 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.
 	 */
-- 
2.45.2.741.gdbec12cfda-goog
Re: [PATCH v2 6/6] ata: libata-scsi: Check ATA_QCFLAG_RTF_FILLED before using result_tf
Posted by Hannes Reinecke 1 year, 5 months ago 
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@google.com>
> ---
>   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.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich
Re: [PATCH v2 6/6] ata: libata-scsi: Check ATA_QCFLAG_RTF_FILLED before using result_tf
Posted by Igor Pylypiv 1 year, 5 months ago 
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@google.com>
> > ---
> >   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@suse.de                                +49 911 74053 688
> SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
> HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich
>
Re: [PATCH v2 6/6] ata: libata-scsi: Check ATA_QCFLAG_RTF_FILLED before using result_tf
Posted by Damien Le Moal 1 year, 5 months ago 
On 6/26/24 09:30, Igor Pylypiv wrote:
> 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@google.com>
>>> ---
>>>   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?

what about ata_dev_dbg() or ata_port_dbg() ?
No message spamming by default and if problems are detected, they can be turned
on to figure out what is going on.

> 
> Damien, Niklas, what are your thoughts on this?
> 
> Thanks,
> Igor
> 
>> Cheers,
>>
>> Hannes
>> -- 
>> Dr. Hannes Reinecke                  Kernel Storage Architect
>> hare@suse.de                                +49 911 74053 688
>> SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
>> HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich
>>

-- 
Damien Le Moal
Western Digital Research
Re: [PATCH v2 6/6] ata: libata-scsi: Check ATA_QCFLAG_RTF_FILLED before using result_tf
Posted by Igor Pylypiv 1 year, 5 months ago 
On Wed, Jun 26, 2024 at 03:21:58PM +0900, Damien Le Moal wrote:
> On 6/26/24 09:30, Igor Pylypiv wrote:
> > 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@google.com>
> >>> ---
> >>>   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?
> 
> what about ata_dev_dbg() or ata_port_dbg() ?
> No message spamming by default and if problems are detected, they can be turned
> on to figure out what is going on.

ata_dev_dbg() should work. Updated the patch in v3.

Thank you!
Igor
> 
> > 
> > Damien, Niklas, what are your thoughts on this?
> > 
> > Thanks,
> > Igor
> > 
> >> Cheers,
> >>
> >> Hannes
> >> -- 
> >> Dr. Hannes Reinecke                  Kernel Storage Architect
> >> hare@suse.de                                +49 911 74053 688
> >> SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
> >> HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich
> >>
> 
> -- 
> Damien Le Moal
> Western Digital Research
>

Patchew 2.1-devel-b67e4c2

© 2016 - 2025 Red Hat, Inc.