During system resume, sd_start_stop_device() submits a START STOP UNIT
command to the SCSI device that is being resumed. That command is not
retried in case of a unit attention and hence may fail. An example:
[16575.983359] sd 0:0:0:3: [sdd] Starting disk
[16575.983693] sd 0:0:0:3: [sdd] Start/Stop Unit failed: Result: hostbyte=0x00 driverbyte=DRIVER_OK
[16575.983712] sd 0:0:0:3: [sdd] Sense Key : 0x6
[16575.983730] sd 0:0:0:3: [sdd] ASC=0x29 ASCQ=0x0
[16575.983738] sd 0:0:0:3: PM: dpm_run_callback(): scsi_bus_resume+0x0/0xa0 returns -5
[16575.983783] sd 0:0:0:3: PM: failed to resume async: error -5
Make the SCSI core retry the START STOP UNIT command if the device
reports that it has been powered on or that it has been reset.
Cc: Damien Le Moal <dlemoal@xxxxxxxxxx>
Cc: Mike Christie <michael.christie@xxxxxxxxxx>
Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
---
Changes compared to v2:
- Dropped the SCMD_RETRY_PASSTHROUGH flag and use the SCSI failure mechanism
instead.
Changes compared to v1:
- Renamed SCMD_RETRY_PASST_ON_UA into SCMD_RETRY_PASSTHROUGH.
drivers/scsi/sd.c | 29 +++++++++++++++++++++++++++++
1 file changed, 29 insertions(+)
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 9db86943d04c..9f09060ab401 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -4093,9 +4093,38 @@ static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
{
unsigned char cmd[6] = { START_STOP }; /* START_VALID */
struct scsi_sense_hdr sshdr;
+ struct scsi_failure failure_defs[] = {
+ {
+ /* Power on, reset, or bus device reset occurred */
+ .sense = UNIT_ATTENTION,
+ .asc = 0x29,
+ .ascq = 0,
+ .result = SAM_STAT_CHECK_CONDITION,
+ },
+ {
+ /* Power on occurred */
+ .sense = UNIT_ATTENTION,
+ .asc = 0x29,
+ .ascq = 1,
+ .result = SAM_STAT_CHECK_CONDITION,
+ },
+ {
+ /* SCSI bus reset */
+ .sense = UNIT_ATTENTION,
+ .asc = 0x29,
+ .ascq = 2,
+ .result = SAM_STAT_CHECK_CONDITION,
+ },
+ {}
+ };
+ struct scsi_failures failures = {
+ .total_allowed = 3,
+ .failure_definitions = failure_defs,
+ };
const struct scsi_exec_args exec_args = {
.sshdr = &sshdr,
.req_flags = BLK_MQ_REQ_PM,
+ .failures = &failures,
};
struct scsi_device *sdp = sdkp->device;
int res;
