trace-view: Handle unknown events more gracefully

Kernel 2.6.35.7 generates invalid trace files due to
/sys/kernel/debug/tracing/events/scsi/scsi_dispatch_cmd_timeout/format
returning "FORMAT TOO BIG" (seems to be fixed in 2.6.36). This makes
pevent_data_event_from_type return NULL, and dereferencing of event
crashes the viewer.

Catch and report the error properly.

Signed-off-by: Jan Kiszka <jan.kiszka@web.de>
LKML-Reference: <4CB758C1.8090906@web.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 6 insertions, 1 deletions

diff --git a/trace-view-store.c b/trace-view-store.c
index 0834df7..34f8155 100644
--- a/trace-view-store.c
+++ b/trace-view-store.c
@@ -507,12 +507,17 @@ trace_view_store_get_value (GtkTreeModel *tree_model,
                 case TRACE_VIEW_STORE_COL_INFO:
                         val = pevent_data_type(pevent, data);
                         event = pevent_data_event_from_type(pevent, val);
+                        if (!event) {
+                                if (column == TRACE_VIEW_STORE_COL_EVENT)
+                                        g_value_set_string(value, "[UNKNOWN EVENT]");
+                                break;
+                        }
+
                         if (column == TRACE_VIEW_STORE_COL_EVENT) {
                                 g_value_set_string(value, event->name);
                                 break;
                         }
 
-                        
                         trace_seq_init(&s);
                         pevent_event_info(&s, event, data);
                         g_value_set_string(value, s.buffer);