5 files changed, 17 insertions, 14 deletions

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 5c8d8eea9e7c..cbae7fb1be15 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -4102,7 +4102,7 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
         return count;
 }
 
-void
+int
 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops)
 {
         struct ftrace_ops_hash old_hash_ops;
@@ -4131,7 +4131,7 @@ unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops)
 
                 /* we do not support '!' for function probes */
                 if (WARN_ON(not))
-                        return;
+                        return -EINVAL;
         }
 
         mutex_lock(&trace_probe_ops.func_hash->regex_lock);
@@ -4140,9 +4140,9 @@ unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops)
         /* Probes only have filters */
         old_hash_ops.notrace_hash = NULL;
 
+        ret = -ENOMEM;
         hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
         if (!hash)
-                /* Hmm, should report this somehow */
                 goto out_unlock;
 
         INIT_LIST_HEAD(&free_list);
@@ -4173,6 +4173,13 @@ unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops)
                         list_add(&entry->free_list, &free_list);
                 }
         }
+
+        /* Nothing found? */
+        if (list_empty(&free_list)) {
+                ret = -EINVAL;
+                goto out_unlock;
+        }
+
         mutex_lock(&ftrace_lock);
         disabled = __disable_ftrace_function_probe();
         /*
@@ -4198,6 +4205,7 @@ unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops)
  out_unlock:
         mutex_unlock(&trace_probe_ops.func_hash->regex_lock);
         free_ftrace_hash(hash);
+        return ret;
 }
 
 static LIST_HEAD(ftrace_commands);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 7a4d578d8887..64a4418a5106 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -6829,10 +6829,8 @@ ftrace_trace_snapshot_callback(struct ftrace_hash *hash,
 
         ops = param ? &snapshot_count_probe_ops :  &snapshot_probe_ops;
 
-        if (glob[0] == '!') {
-                unregister_ftrace_function_probe_func(glob+1, ops);
-                return 0;
-        }
+        if (glob[0] == '!')
+                return unregister_ftrace_function_probe_func(glob+1, ops);
 
         if (!param)
                 goto out_reg;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 86aa5a2222ba..31d80bff9ee6 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -963,7 +963,7 @@ void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
 extern int
 register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
                               void *data);
-extern void
+extern int
 unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
 
 int register_ftrace_command(struct ftrace_func_command *cmd);
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 37902107c44f..9e07a5b3869b 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2652,8 +2652,7 @@ event_enable_func(struct ftrace_hash *hash,
                 ops = param ? &event_disable_count_probe_ops : &event_disable_probe_ops;
 
         if (glob[0] == '!') {
-                unregister_ftrace_function_probe_func(glob+1, ops);
-                ret = 0;
+                ret = unregister_ftrace_function_probe_func(glob+1, ops);
                 goto out;
         }
 
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 56d0fe1e4ea1..dcb4d37ed4bd 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -586,10 +586,8 @@ ftrace_trace_probe_callback(struct ftrace_probe_ops *ops,
         if (!enable)
                 return -EINVAL;
 
-        if (glob[0] == '!') {
-                unregister_ftrace_function_probe_func(glob+1, ops);
-                return 0;
-        }
+        if (glob[0] == '!')
+                return unregister_ftrace_function_probe_func(glob+1, ops);
 
         if (!param)
                 goto out_reg;