Index: linux-2.6.22/drivers/md/dm-mpath-rdac.c
===================================================================
--- linux-2.6.22.orig/drivers/md/dm-mpath-rdac.c
+++ linux-2.6.22/drivers/md/dm-mpath-rdac.c
@@ -229,6 +229,13 @@ static void mode_select_endio(struct req
 	struct scsi_sense_hdr sense_hdr;
 	int sense = 0, fail = 0;
 
+	DMINFO("MODE_SELECT of %s returned error %d; host_byte 0x%x, "
+		"msg_byte 0x%x, status_byte 0x%x\n",
+		h->path->dev->name, error,
+		host_byte(req->errors),
+		msg_byte(req->errors),
+		status_byte(req->errors));
+
 	if (had_failures(req, error)) {
 		fail = 1;
 		goto failed;