3 files changed, 7 insertions, 2 deletions

diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index 2a4a40749911..07e0a6d64a24 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -16,13 +16,16 @@ struct dentry;
  *     bash-15816 [01]   235.197585: idle_cpu <- irq_enter
  */
 struct trace_entry {
-        int                     type;
+        unsigned short          type;
         unsigned char           flags;
         unsigned char           preempt_count;
         int                     pid;
         int                     tgid;
 };
 
+#define FTRACE_MAX_EVENT                                                \
+        ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
+
 /*
  * Trace iterator - used by printout routines who present trace
  * results to users and which routines might sleep, etc:
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 5d6e879cf875..9887131afa03 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -398,7 +398,7 @@ static int trace_write_header(struct trace_seq *s)
                                 "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
                                 "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
                                 "\n",
-                                FIELD(int, type),
+                                FIELD(unsigned short, type),
                                 FIELD(unsigned char, flags),
                                 FIELD(unsigned char, preempt_count),
                                 FIELD(int, pid),
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 83a8abb9640f..06997e75114b 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -537,6 +537,8 @@ int register_ftrace_event(struct trace_event *event)
  out:
         mutex_unlock(&trace_event_mutex);
 
+        WARN_ON_ONCE(next_event_type > FTRACE_MAX_EVENT);
+
         return ret;
 }
 EXPORT_SYMBOL_GPL(register_ftrace_event);