[S390] monwriter find header logic.

Fix logic for finding matching buffers.
Signed-off-by: Melissa Howland <melissah@us.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/char/monwriter.c

@@ -73,12 +73,15 @@ static inline struct mon_buf *monwrite_find_hdr(struct mon_private *monpriv,
 	struct mon_buf *entry, *next;
 
 	list_for_each_entry_safe(entry, next, &monpriv->list, list)
-		if (entry->hdr.applid == monhdr->applid &&
+		if ((entry->hdr.mon_function == monhdr->mon_function ||
+		     monhdr->mon_function == MONWRITE_STOP_INTERVAL) &&
+		    entry->hdr.applid == monhdr->applid &&
 		    entry->hdr.record_num == monhdr->record_num &&
 		    entry->hdr.version == monhdr->version &&
 		    entry->hdr.release == monhdr->release &&
 		    entry->hdr.mod_level == monhdr->mod_level)
 			return entry;
+
 	return NULL;
 }
 
@@ -92,6 +95,8 @@ static int monwrite_new_hdr(struct mon_private *monpriv)
 	    monhdr->mon_function > MONWRITE_START_CONFIG ||
 	    monhdr->hdrlen != sizeof(struct monwrite_hdr))
 		return -EINVAL;
+	monbuf = NULL;
+	if (monhdr->mon_function != MONWRITE_GEN_EVENT)
 		monbuf = monwrite_find_hdr(monpriv, monhdr);
 	if (monbuf) {
 		if (monhdr->mon_function == MONWRITE_STOP_INTERVAL) {
@@ -104,7 +109,7 @@ static int monwrite_new_hdr(struct mon_private *monpriv)
 			kfree(monbuf);
 			monbuf = NULL;
 		}
-	} else {
+	} else if (monhdr->mon_function != MONWRITE_STOP_INTERVAL) {
 		if (mon_buf_count >= mon_max_bufs)
 			return -ENOSPC;
 		monbuf = kzalloc(sizeof(struct mon_buf), GFP_KERNEL);
@@ -118,6 +123,7 @@ static int monwrite_new_hdr(struct mon_private *monpriv)
 		}
 		monbuf->hdr = *monhdr;
 		list_add_tail(&monbuf->list, &monpriv->list);
+		if (monhdr->mon_function != MONWRITE_GEN_EVENT)
 			mon_buf_count++;
 	}
 	monpriv->current_buf = monbuf;