1 files changed, 23 insertions, 7 deletions

diff --git a/drivers/xen/xen-scsiback.c b/drivers/xen/xen-scsiback.c
index e33f95c91b09..c7036e0e41bd 100644
--- a/drivers/xen/xen-scsiback.c
+++ b/drivers/xen/xen-scsiback.c
@@ -611,6 +611,25 @@ static void scsiback_disconnect(struct vscsibk_info *info)
 	xenbus_unmap_ring_vfree(info->dev, info->ring.sring);
 }
 
+/*
+ * Send the error response for a request that did not reach the target core
+ * and return its tag.  Free the tag before the response drops the v2p
+ * reference that keeps the session alive, and snapshot what the response
+ * needs since returning the tag can let the slot be reused.
+ */
+static void scsiback_resp_and_free(struct vscsibk_pend *pending_req,
+				   int32_t result)
+{
+	struct vscsibk_info *info = pending_req->info;
+	struct v2p_entry *v2p = pending_req->v2p;
+	struct se_session *se_sess = v2p->tpg->tpg_nexus->tvn_se_sess;
+	u16 rqid = pending_req->rqid;
+
+	target_free_tag(se_sess, &pending_req->se_cmd);
+	scsiback_send_response(info, NULL, result, 0, rqid);
+	kref_put(&v2p->kref, scsiback_free_translation_entry);
+}
+
 static void scsiback_device_action(struct vscsibk_pend *pending_req,
 	enum tcm_tmreq_table act, int tag)
 {
@@ -639,7 +658,7 @@ static void scsiback_device_action(struct vscsibk_pend *pending_req,
 	return;
 
 err:
-	scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
+	scsiback_resp_and_free(pending_req, err);
 }
 
 /*
@@ -792,9 +811,8 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info,
 		case VSCSIIF_ACT_SCSI_CDB:
 			if (scsiback_gnttab_data_map(&ring_req, pending_req)) {
 				scsiback_fast_flush_area(pending_req);
-				scsiback_do_resp_with_sense(NULL,
-						DID_ERROR << 16, 0, pending_req);
-				transport_generic_free_cmd(&pending_req->se_cmd, 0);
+				scsiback_resp_and_free(pending_req,
+						       DID_ERROR << 16);
 			} else {
 				scsiback_cmd_exec(pending_req);
 			}
@@ -808,9 +826,7 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info,
 			break;
 		default:
 			pr_err_ratelimited("invalid request\n");
-			scsiback_do_resp_with_sense(NULL, DID_ERROR << 16, 0,
-						    pending_req);
-			transport_generic_free_cmd(&pending_req->se_cmd, 0);
+			scsiback_resp_and_free(pending_req, DID_ERROR << 16);
 			break;
 		}