1 files changed, 33 insertions, 16 deletions

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index df93392aad89..853f6f0a4b4a 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1170,8 +1170,14 @@ alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash)
         return NULL;
 }
 
+static void
+ftrace_hash_rec_disable(struct ftrace_ops *ops, int filter_hash);
+static void
+ftrace_hash_rec_enable(struct ftrace_ops *ops, int filter_hash);
+
 static int
-ftrace_hash_move(struct ftrace_hash **dst, struct ftrace_hash *src)
+ftrace_hash_move(struct ftrace_ops *ops, int enable,
+                 struct ftrace_hash **dst, struct ftrace_hash *src)
 {
         struct ftrace_func_entry *entry;
         struct hlist_node *tp, *tn;
@@ -1181,9 +1187,16 @@ ftrace_hash_move(struct ftrace_hash **dst, struct ftrace_hash *src)
         unsigned long key;
         int size = src->count;
         int bits = 0;
+        int ret;
         int i;
 
         /*
+         * Remove the current set, update the hash and add
+         * them back.
+         */
+        ftrace_hash_rec_disable(ops, enable);
+
+        /*
          * If the new source is empty, just free dst and assign it
          * the empty_hash.
          */
@@ -1203,9 +1216,10 @@ ftrace_hash_move(struct ftrace_hash **dst, struct ftrace_hash *src)
         if (bits > FTRACE_HASH_MAX_BITS)
                 bits = FTRACE_HASH_MAX_BITS;
 
+        ret = -ENOMEM;
         new_hash = alloc_ftrace_hash(bits);
         if (!new_hash)
-                return -ENOMEM;
+                goto out;
 
         size = 1 << src->size_bits;
         for (i = 0; i < size; i++) {
@@ -1224,7 +1238,16 @@ ftrace_hash_move(struct ftrace_hash **dst, struct ftrace_hash *src)
         rcu_assign_pointer(*dst, new_hash);
         free_ftrace_hash_rcu(old_hash);
 
-        return 0;
+        ret = 0;
+ out:
+        /*
+         * Enable regardless of ret:
+         *  On success, we enable the new hash.
+         *  On failure, we re-enable the original hash.
+         */
+        ftrace_hash_rec_enable(ops, enable);
+
+        return ret;
 }
 
 /*
@@ -2845,7 +2868,7 @@ ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
                 ftrace_match_records(hash, buf, len);
 
         mutex_lock(&ftrace_lock);
-        ret = ftrace_hash_move(orig_hash, hash);
+        ret = ftrace_hash_move(ops, enable, orig_hash, hash);
         mutex_unlock(&ftrace_lock);
 
         mutex_unlock(&ftrace_regex_lock);
@@ -3028,18 +3051,12 @@ ftrace_regex_release(struct inode *inode, struct file *file)
                         orig_hash = &iter->ops->notrace_hash;
 
                 mutex_lock(&ftrace_lock);
-                /*
-                 * Remove the current set, update the hash and add
-                 * them back.
-                 */
-                ftrace_hash_rec_disable(iter->ops, filter_hash);
-                ret = ftrace_hash_move(orig_hash, iter->hash);
-                if (!ret) {
-                        ftrace_hash_rec_enable(iter->ops, filter_hash);
-                        if (iter->ops->flags & FTRACE_OPS_FL_ENABLED
-                            && ftrace_enabled)
-                                ftrace_run_update_code(FTRACE_ENABLE_CALLS);
-                }
+                ret = ftrace_hash_move(iter->ops, filter_hash,
+                                       orig_hash, iter->hash);
+                if (!ret && (iter->ops->flags & FTRACE_OPS_FL_ENABLED)
+                    && ftrace_enabled)
+                        ftrace_run_update_code(FTRACE_ENABLE_CALLS);
+
                 mutex_unlock(&ftrace_lock);
         }
         free_ftrace_hash(iter->hash);