Re: [PATCH 1/3] ftrace: prevent freeing of all failed updates

[Abhishek Sagar <sagar.abhishek@gmail.com>]

Steven Rostedt wrote:
> If we unload a module and reload it, will it ever get converted again?

The intent was always to filter core kernel functions to prevent their freeing.
Here's a fix which should allow re-recording of module call-sites.

---
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index ec54cb7..77c9392 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -437,7 +437,7 @@ static void ftrace_replace_code(int enable)
 			if (failed && (rec->flags & FTRACE_FL_CONVERTED)) {
 				rec->flags |= FTRACE_FL_FAILED;
 				if ((system_state == SYSTEM_BOOTING) ||
-				    !kernel_text_address(rec->ip)) {
+				    !core_kernel_text(rec->ip)) {
 					ftrace_del_hash(rec);
 					ftrace_free_rec(rec);
 				}
@@ -658,10 +658,9 @@ static int __ftrace_update_code(void *ignore)
 				ftrace_update_cnt++;
 			} else {
 				if ((system_state == SYSTEM_BOOTING) ||
-				    !kernel_text_address(p->ip)) {
+				    !core_kernel_text(p->ip)) {
 					ftrace_del_hash(p);
 					ftrace_free_rec(p);
-
 				}
 			}
 		}