2 files changed, 11 insertions, 7 deletions

diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c
index 59e662df5774..78d52a4c55f5 100644
--- a/drivers/s390/scsi/zfcp_erp.c
+++ b/drivers/s390/scsi/zfcp_erp.c
@@ -1607,7 +1607,6 @@ check_target:
 static int zfcp_erp_thread(void *data)
 {
 	struct zfcp_adapter *adapter = (struct zfcp_adapter *) data;
-	struct list_head *next;
 	struct zfcp_erp_action *act;
 	unsigned long flags;
 
@@ -1620,12 +1619,11 @@ static int zfcp_erp_thread(void *data)
 			break;
 
 		write_lock_irqsave(&adapter->erp_lock, flags);
-		next = adapter->erp_ready_head.next;
+		act = list_first_entry_or_null(&adapter->erp_ready_head,
+					       struct zfcp_erp_action, list);
 		write_unlock_irqrestore(&adapter->erp_lock, flags);
 
-		if (next != &adapter->erp_ready_head) {
-			act = list_entry(next, struct zfcp_erp_action, list);
-
+		if (act) {
 			/* there is more to come after dismission, no notify */
 			if (zfcp_erp_strategy(act) != ZFCP_ERP_DISMISSED)
 				zfcp_erp_wakeup(adapter);
diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c
index 140186fe1d1e..6cb963a06777 100644
--- a/drivers/s390/scsi/zfcp_fsf.c
+++ b/drivers/s390/scsi/zfcp_fsf.c
@@ -426,9 +426,14 @@ static void zfcp_fsf_protstatus_eval(struct zfcp_fsf_req *req)
  * or it has been dismissed due to a queue shutdown, this function
  * is called to process the completion status and trigger further
  * events related to the FSF request.
+ * Caller must ensure that the request has been removed from
+ * adapter->req_list, to protect against concurrent modification
+ * by zfcp_erp_strategy_check_fsfreq().
  */
 static void zfcp_fsf_req_complete(struct zfcp_fsf_req *req)
 {
+	struct zfcp_erp_action *erp_action;
+
 	if (unlikely(zfcp_fsf_req_is_status_read_buffer(req))) {
 		zfcp_fsf_status_read_handler(req);
 		return;
@@ -439,8 +444,9 @@ static void zfcp_fsf_req_complete(struct zfcp_fsf_req *req)
 	zfcp_fsf_fsfstatus_eval(req);
 	req->handler(req);
 
-	if (req->erp_action)
-		zfcp_erp_notify(req->erp_action, 0);
+	erp_action = req->erp_action;
+	if (erp_action)
+		zfcp_erp_notify(erp_action, 0);
 
 	if (likely(req->status & ZFCP_STATUS_FSFREQ_CLEANUP))
 		zfcp_fsf_req_free(req);