trace-cmd: Don't SIGSEGV in trace-graph.c:load_handle

This 'fixes' another crash I encountered.  Don't try to dereference
NULL records.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
LKML-Reference: <1279586810-29859-3-git-send-email-ddaney@caviumnetworks.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/trace-graph.c b/trace-graph.c
index f940874..a53ab84 100644
--- a/trace-graph.c
+++ b/trace-graph.c
@@ -2413,6 +2413,8 @@ static int load_handle(struct graph_info *ginfo,
 
                 free_record(record);
                 record = tracecmd_read_cpu_last(handle, cpu);
+                if (!record)
+                        continue;
 
                 if (record->ts > ginfo->end_time)
                         ginfo->end_time = record->ts;