1 files changed, 28 insertions, 15 deletions

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 37f9e90d241c..92376aeac4a7 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1507,25 +1507,38 @@ static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec)
 static void ftrace_remove_tramp(struct ftrace_ops *ops,
                                 struct dyn_ftrace *rec)
 {
-        struct ftrace_func_entry *entry;
-
-        entry = ftrace_lookup_ip(ops->tramp_hash, rec->ip);
-        if (!entry)
+        /* If TRAMP is not set, no ops should have a trampoline for this */
+        if (!(rec->flags & FTRACE_FL_TRAMP))
                 return;
 
+        rec->flags &= ~FTRACE_FL_TRAMP;
+
+        if ((!ftrace_hash_empty(ops->func_hash->filter_hash) &&
+             !ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip)) ||
+            ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip))
+                return;
         /*
          * The tramp_hash entry will be removed at time
          * of update.
          */
         ops->nr_trampolines--;
-        rec->flags &= ~FTRACE_FL_TRAMP;
 }
 
-static void ftrace_clear_tramps(struct dyn_ftrace *rec)
+static void ftrace_clear_tramps(struct dyn_ftrace *rec, struct ftrace_ops *ops)
 {
         struct ftrace_ops *op;
 
+        /* If TRAMP is not set, no ops should have a trampoline for this */
+        if (!(rec->flags & FTRACE_FL_TRAMP))
+                return;
+
         do_for_each_ftrace_op(op, ftrace_ops_list) {
+                /*
+                 * This function is called to clear other tramps
+                 * not the one that is being updated.
+                 */
+                if (op == ops)
+                        continue;
                 if (op->nr_trampolines)
                         ftrace_remove_tramp(op, rec);
         } while_for_each_ftrace_op(op);
@@ -1626,13 +1639,10 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
                                 /*
                                  * If we are adding another function callback
                                  * to this function, and the previous had a
-                                 * trampoline used, then we need to go back to
-                                 * the default trampoline.
+                                 * custom trampoline in use, then we need to go
+                                 * back to the default trampoline.
                                  */
-                                rec->flags &= ~FTRACE_FL_TRAMP;
-
-                                /* remove trampolines from any ops for this rec */
-                                ftrace_clear_tramps(rec);
+                                ftrace_clear_tramps(rec, ops);
                         }
 
                         /*
@@ -1935,8 +1945,8 @@ unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec)
         if (rec->flags & FTRACE_FL_TRAMP) {
                 ops = ftrace_find_tramp_ops_new(rec);
                 if (FTRACE_WARN_ON(!ops || !ops->trampoline)) {
-                        pr_warning("Bad trampoline accounting at: %p (%pS)\n",
-                                    (void *)rec->ip, (void *)rec->ip);
+                        pr_warn("Bad trampoline accounting at: %p (%pS) (%lx)\n",
+                                (void *)rec->ip, (void *)rec->ip, rec->flags);
                         /* Ftrace is shutting down, return anything */
                         return (unsigned long)FTRACE_ADDR;
                 }
@@ -2266,7 +2276,10 @@ static int ftrace_save_ops_tramp_hash(struct ftrace_ops *ops)
         } while_for_each_ftrace_rec();
 
         /* The number of recs in the hash must match nr_trampolines */
-        FTRACE_WARN_ON(ops->tramp_hash->count != ops->nr_trampolines);
+        if (FTRACE_WARN_ON(ops->tramp_hash->count != ops->nr_trampolines))
+                pr_warn("count=%ld trampolines=%d\n",
+                        ops->tramp_hash->count,
+                        ops->nr_trampolines);
 
         return 0;
 }