[PATCH 4.9 111/116] scsi: megaraid_sas: Do not initiate OCR if controller is not in ready state

From: Greg Kroah-Hartman
Date: Thu Feb 13 2020 - 11:03:09 EST


From: Anand Lodnoor <anand.lodnoor@xxxxxxxxxxxx>

commit 6d7537270e3283b92f9b327da9d58a4de40fe8d0 upstream.

Driver initiates OCR if a DCMD command times out. But there is a deadlock
if the driver attempts to invoke another OCR before the mutex lock
(reset_mutex) is released from the previous session of OCR.

This patch takes care of the above scenario using new flag
MEGASAS_FUSION_OCR_NOT_POSSIBLE to indicate if OCR is possible.

Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/1579000882-20246-9-git-send-email-anand.lodnoor@xxxxxxxxxxxx
Signed-off-by: Shivasharan S <shivasharan.srikanteshwara@xxxxxxxxxxxx>
Signed-off-by: Anand Lodnoor <anand.lodnoor@xxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>


---
drivers/scsi/megaraid/megaraid_sas_base.c | 3 ++-
drivers/scsi/megaraid/megaraid_sas_fusion.c | 3 ++-
drivers/scsi/megaraid/megaraid_sas_fusion.h | 1 +
3 files changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -3978,7 +3978,8 @@ dcmd_timeout_ocr_possible(struct megasas
if (!instance->ctrl_context)
return KILL_ADAPTER;
else if (instance->unload ||
- test_bit(MEGASAS_FUSION_IN_RESET, &instance->reset_flags))
+ test_bit(MEGASAS_FUSION_OCR_NOT_POSSIBLE,
+ &instance->reset_flags))
return IGNORE_TIMEOUT;
else
return INITIATE_OCR;
--- a/drivers/scsi/megaraid/megaraid_sas_fusion.c
+++ b/drivers/scsi/megaraid/megaraid_sas_fusion.c
@@ -3438,6 +3438,7 @@ int megasas_reset_fusion(struct Scsi_Hos
if (instance->requestorId && !instance->skip_heartbeat_timer_del)
del_timer_sync(&instance->sriov_heartbeat_timer);
set_bit(MEGASAS_FUSION_IN_RESET, &instance->reset_flags);
+ set_bit(MEGASAS_FUSION_OCR_NOT_POSSIBLE, &instance->reset_flags);
atomic_set(&instance->adprecovery, MEGASAS_ADPRESET_SM_POLLING);
instance->instancet->disable_intr(instance);
msleep(1000);
@@ -3594,7 +3595,7 @@ fail_kill_adapter:
atomic_set(&instance->adprecovery, MEGASAS_HBA_OPERATIONAL);
}
out:
- clear_bit(MEGASAS_FUSION_IN_RESET, &instance->reset_flags);
+ clear_bit(MEGASAS_FUSION_OCR_NOT_POSSIBLE, &instance->reset_flags);
mutex_unlock(&instance->reset_mutex);
return retval;
}
--- a/drivers/scsi/megaraid/megaraid_sas_fusion.h
+++ b/drivers/scsi/megaraid/megaraid_sas_fusion.h
@@ -93,6 +93,7 @@ enum MR_RAID_FLAGS_IO_SUB_TYPE {

#define MEGASAS_FP_CMD_LEN 16
#define MEGASAS_FUSION_IN_RESET 0
+#define MEGASAS_FUSION_OCR_NOT_POSSIBLE 1
#define THRESHOLD_REPLY_COUNT 50
#define JBOD_MAPS_COUNT 2