Since commit 2e1d2e65e7 ("ata: libata-scsi: terminate deferred commands
on time out"), atapi_qc_complete() sets SAM_STAT_CHECK_CONDITION for a
failed command only if cmd->result is zero, so that the DID_TIME_OUT or
DID_REQUEUE host byte of a terminated command is preserved.
However, cmd->result can also be non-zero for a regular failed ATAPI
command completed through libata EH: ata_eh_analyze_tf() calls
ata_eh_decide_disposition(), that is, scsi_check_sense(), on the sense
data obtained with REQUEST SENSE, and scsi_check_sense() sets the SCSI
midlayer internal byte of the result for some sense codes, e.g.
SCSIML_STAT_TGT_FAILURE for ILLEGAL REQUEST with ASC 0x20 (INVALID
COMMAND OPERATION CODE) or 0x24 (INVALID FIELD IN CDB), or
SCSIML_STAT_MED_ERROR for MEDIUM ERROR with ASC 0x11 (UNRECOVERED READ
ERROR). For such commands, atapi_qc_complete() keeps the result as is and
the command completes with a GOOD status byte, even though it failed and
valid sense data is available.
As a result, passthrough users see these failed ATAPI commands as
successful. For example, with the emulated IDE CD-ROM drive of QEMU and
no medium loaded, a PLAY AUDIO MSF command issued with SG_IO completes
with status 0x00 (and no DRIVER_SENSE) instead of 0x02 (CHECK CONDITION)
with sense key ILLEGAL REQUEST, ASC/ASCQ 0x20/0x00, and the CDROM ioctls
CDROMPLAYTRKIND, CDROMSUBCHNL, CDROMPAUSE, CDROMRESUME, CDROMPLAYMSF and
CDROM_GET_MCN return 0 instead of -ENOMEDIUM or -EOPNOTSUPP.
Fix this by setting the status byte to SAM_STAT_CHECK_CONDITION whenever
the host byte is not set. Use set_status_byte() rather than overwriting
the whole result, so that the SCSI midlayer internal byte set by
scsi_check_sense() is preserved, as ata_scsi_qc_complete() already does
for ATA commands.
Fixes: 2e1d2e65e7 ("ata: libata-scsi: terminate deferred commands on time out")
Cc: [email protected]
Suggested-by: Niklas Cassel <[email protected]>
Signed-off-by: Hengyu Liang <[email protected]>
Reviewed-by: Damien Le Moal <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Niklas Cassel <[email protected]>
Hengyu Liang
bc8ce2cea5