Re: [PATCH v3 0/6] libsas and drivers: NCQ error handling

From: Damien Le Moal
Date: Tue Sep 20 2022 - 23:59:55 EST


On 9/7/22 00:08, 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, if necessary

Indeed for the hisi_sas driver we want to add similar handling for NCQ
errors.

This series add a new libsas API - sas_ata_device_link_abort() - to handle
host NCQ errors, and fixes up pm8001 and hisi_sas drivers to use it.

A difference in the pm8001 driver NCQ error handling is that we send
SATA_ABORT per-task prior to read log ext10, but I feel that this should
not make a difference to the error handling.

Damien kindly tested previous the series for pm8001, but any further pm8001
testing would be appreciated as I have since tweaked pm8001 handling again.
This is because the pm8001 driver hangs on my arm64 machine read log ext10
command.

I tested this series on top of the current Linus tree. All look good. As ususal, I hammered an SMR drive connected to a pm80xx adapter and generated lots of invalid commands to check EH. No issues that I can see.
E.g., an unaligned write error look like this:

[ 5384.194853] pm80xx0:: mpi_sata_event 2685: SATA EVENT 0x23
[ 5384.238720] sas: Enter sas_scsi_recover_host busy: 1 failed: 1
[ 5384.246171] sas: sas_scsi_find_task: aborting task 0x0000000050be2a4b
[ 5384.254654] pm80xx0:: mpi_sata_completion 2292: task null, freeing CCB tag 2
[ 5384.254676] sas: sas_scsi_find_task: task 0x0000000050be2a4b is aborted
[ 5384.294659] sas: sas_eh_handle_sas_errors: task 0x0000000050be2a4b is aborted
[ 5384.318691] ata22.00: exception Emask 0x0 SAct 0x200000 SErr 0x0 action 0x0
[ 5384.328425] ata22.00: failed command: WRITE FPDMA QUEUED
[ 5384.336277] ata22.00: cmd 61/01:00:01:00:ea/00:00:02:00:00/40 tag 21 ncq dma 4096 out
[ 5384.336277] res 43/04:01:01:00:ea/00:00:02:00:00/00 Emask 0x400 (NCQ error) <F>
[ 5384.357299] ata22.00: status: { DRDY SENSE ERR }
[ 5384.364459] ata22.00: error: { ABRT }
[ 5384.553177] ata22.00: configured for UDMA/133
[ 5384.560343] sd 19:0:3:0: [sdl] tag#80 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_OK cmd_age=0s
[ 5384.572175] sd 19:0:3:0: [sdl] tag#80 Sense Key : Illegal Request [current]
[ 5384.581765] sd 19:0:3:0: [sdl] tag#80 Add. Sense: Unaligned write command
[ 5384.591126] sd 19:0:3:0: [sdl] tag#80 CDB: Write(16) 8a 00 00 00 00 00 02 ea 00 01 00 00 00 01 00 00
[ 5384.602938] I/O error, dev sdl, sector 391118856 op 0x1:(WRITE) flags 0x8800 phys_seg 1 prio class 2
[ 5384.613854] ata22: EH complete
[ 5384.618570] sas: --- Exit sas_scsi_recover_host: busy: 0 failed: 1 tries: 1

So looks good to me.

Feel free to add:

Tested-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>


Finally with these changes we can make the libsas task alloc/free APIs
private, which they should always have been.

Based on v6.0-rc4

[0] https://lore.kernel.org/linux-scsi/8fb3b093-55f0-1fab-81f4-e8519810a978@xxxxxxxxxx/

Changes since v2:
- Stop sending SATA_ABORT all for pm8001 handling
- Make "reset" optional in sas_ata_device_link_abort()

Changes since v1:
- Rename sas_ata_link_abort() -> sas_ata_device_link_abort()
- Set EH RESET flag in sas_ata_device_link_abort()
- Add Jack's Ack tags
- Rebase

John Garry (5):
scsi: pm8001: Modify task abort handling for SATA task
scsi: libsas: Add sas_ata_device_link_abort()
scsi: pm8001: Use sas_ata_device_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 | 12 ++
drivers/scsi/libsas/sas_init.c | 3 -
drivers/scsi/libsas/sas_internal.h | 4 +
drivers/scsi/pm8001/pm8001_hwi.c | 186 ++++---------------------
drivers/scsi/pm8001/pm8001_sas.c | 8 ++
drivers/scsi/pm8001/pm8001_sas.h | 4 -
drivers/scsi/pm8001/pm80xx_hwi.c | 177 +++--------------------
include/scsi/libsas.h | 4 -
include/scsi/sas_ata.h | 6 +
11 files changed, 96 insertions(+), 335 deletions(-)


--
Damien Le Moal
Western Digital Research