Re: [PATCH 0/6] libsas and drivers: NCQ error handling

[Damien Le Moal <damien.lemoal@opensource.wdc.com>]

On 2022/07/22 4:24, John Garry wrote:
> As reported in [0], the pm8001 driver NCQ error handling more or less
> duplicates what libata does in link error handling, as follows:
> - abort all commands
> - do autopsy with read log ext 10 command
> - reset the target to recover
> 
> Indeed for the hisi_sas driver we want to add similar handling for NCQ
> errors.
> 
> This series add a new libsas API - sas_ata_link_abort() - to handle host
> NCQ errors, and fixes up pm8001 and hisi_sas drivers to use it. As
> mentioned in the pm8001 changeover patch, I would prefer a better place to
> locate the SATA ABORT command (rather that nexus reset callback).
> 
> I would appreciate some testing of the pm8001 change as the read log ext10
> command mostly hangs on my arm64 machine - these arm64 hangs are a known
> issue.

I applied this series on top of the current Linus tree and ran some tests: a
bunch of fio runs and also ran libzbc test suites on a SATA SMR drive as that
generates many command failures. No problems detected, the tests all pass.
FYI, messages for failed commands look like this:

pm80xx0:: mpi_sata_event 2685: SATA EVENT 0x23
sas: Enter sas_scsi_recover_host busy: 1 failed: 1
sas: sas_scsi_find_task: aborting task 0x00000000ba62a907
pm80xx0:: mpi_sata_completion 2292: task null, freeing CCB tag 2
sas: sas_scsi_find_task: task 0x00000000ba62a907 is aborted
sas: sas_eh_handle_sas_errors: task 0x00000000ba62a907 is aborted
ata21.00: exception Emask 0x0 SAct 0x20000000 SErr 0x0 action 0x0
ata21.00: failed command: WRITE FPDMA QUEUED
ata21.00: cmd 61/02:00:ff:ff:ea/00:00:02:00:00/40 tag 29 ncq dma 8192 out
res 43/04:02:ff:ff:ea/00:00:02:00:00/00 Emask 0x400 (NCQ error) <F>
ata21.00: status: { DRDY SENSE ERR }
ata21.00: error: { ABRT }
ata21.00: configured for UDMA/133
ata21: EH complete
sas: --- Exit sas_scsi_recover_host: busy: 0 failed: 1 tries: 1

Seems all good to me.

> 
> Finally with these changes we can make the libsas task alloc/free APIs
> private, which they should always have been.
> 
> Based on v5.19-rc6
> 
> [0] https://lore.kernel.org/linux-scsi/8fb3b093-55f0-1fab-81f4-e8519810a978@huawei.com/
> 
> John Garry (5):
>   scsi: pm8001: Modify task abort handling for SATA task
>   scsi: libsas: Add sas_ata_link_abort()
>   scsi: pm8001: Use sas_ata_link_abort() to handle NCQ errors
>   scsi: hisi_sas: Don't issue ATA softreset in hisi_sas_abort_task()
>   scsi: libsas: Make sas_{alloc, alloc_slow, free}_task() private
> 
> Xingui Yang (1):
>   scsi: hisi_sas: Add SATA_DISK_ERR bit handling for v3 hw
> 
>  drivers/scsi/hisi_sas/hisi_sas_main.c  |   5 +-
>  drivers/scsi/hisi_sas/hisi_sas_v3_hw.c |  22 ++-
>  drivers/scsi/libsas/sas_ata.c          |  10 ++
>  drivers/scsi/libsas/sas_init.c         |   3 -
>  drivers/scsi/libsas/sas_internal.h     |   4 +
>  drivers/scsi/pm8001/pm8001_hwi.c       | 194 +++++++------------------
>  drivers/scsi/pm8001/pm8001_sas.c       |  13 ++
>  drivers/scsi/pm8001/pm8001_sas.h       |   8 +-
>  drivers/scsi/pm8001/pm80xx_hwi.c       | 177 ++--------------------
>  include/scsi/libsas.h                  |   4 -
>  include/scsi/sas_ata.h                 |   5 +
>  11 files changed, 132 insertions(+), 313 deletions(-)
> 


-- 
Damien Le Moal
Western Digital Research