3 files changed, 21 insertions, 0 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 4164a344e72a..dd40d2320346 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -639,6 +639,16 @@ void tracing_reset_online_cpus(struct trace_array *tr)
                 tracing_reset(tr, cpu);
 }
 
+void tracing_reset_current(int cpu)
+{
+        tracing_reset(&global_trace, cpu);
+}
+
+void tracing_reset_current_online_cpus(void)
+{
+        tracing_reset_online_cpus(&global_trace);
+}
+
 #define SAVED_CMDLINES 128
 #define NO_CMDLINE_MAP UINT_MAX
 static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1];
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 777c6c3a0cde..ba25793ffe67 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -409,6 +409,8 @@ int tracing_is_enabled(void);
 void trace_wake_up(void);
 void tracing_reset(struct trace_array *tr, int cpu);
 void tracing_reset_online_cpus(struct trace_array *tr);
+void tracing_reset_current(int cpu);
+void tracing_reset_current_online_cpus(void);
 int tracing_open_generic(struct inode *inode, struct file *filp);
 struct dentry *trace_create_file(const char *name,
                                  mode_t mode,
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 8d579ff23610..6d2c842a0248 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -932,9 +932,11 @@ static void trace_module_remove_events(struct module *mod)
 {
         struct ftrace_module_file_ops *file_ops;
         struct ftrace_event_call *call, *p;
+        bool found = false;
 
         list_for_each_entry_safe(call, p, &ftrace_events, list) {
                 if (call->mod == mod) {
+                        found = true;
                         if (call->enabled) {
                                 call->enabled = 0;
                                 call->unregfunc();
@@ -957,6 +959,13 @@ static void trace_module_remove_events(struct module *mod)
                 list_del(&file_ops->list);
                 kfree(file_ops);
         }
+
+        /*
+         * It is safest to reset the ring buffer if the module being unloaded
+         * registered any events.
+         */
+        if (found)
+                tracing_reset_current_online_cpus();
 }
 
 static int trace_module_notify(struct notifier_block *self,