[patch 05/26] tracing: correct module boundaries for ftrace_release

Greg KH
2009-10-09T23:17:17Z

[-- Attachment #1: tracing-correct-module-boundaries-for-ftrace_release.patch --]
[-- Type: text/plain, Size: 2334 bytes --]

2.6.31-stable review patch. If anyone has any objections, please let us know.

------------------
From: jolsa@redhat.com <jolsa@redhat.com>

commit e7247a15ff3bbdab0a8b402dffa1171e5c05a8e0 upstream.

When the module is about the unload we release its call records.
The ftrace_release function was given wrong values representing
the module core boundaries, thus not releasing its call records.

Plus making ftrace_release function module specific.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1254934835-363-3-git-send-email-jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
include/linux/ftrace.h | 2 +-
kernel/trace/ftrace.c | 12 ++++--------
2 files changed, 5 insertions(+), 9 deletions(-)

--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -241,7 +241,7 @@ extern void ftrace_enable_daemon(void);
# define ftrace_set_filter(buf, len, reset) do { } while (0)
# define ftrace_disable_daemon() do { } while (0)
# define ftrace_enable_daemon() do { } while (0)
-static inline void ftrace_release(void *start, unsigned long size) { }
+static inline void ftrace_release_mod(struct module *mod) {}
static inline int register_ftrace_command(struct ftrace_func_command *cmd)
{
return -EINVAL;
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2801,19 +2801,17 @@ static int ftrace_convert_nops(struct mo
}

#ifdef CONFIG_MODULES
-void ftrace_release(void *start, void *end)
+void ftrace_release_mod(struct module *mod)
{
struct dyn_ftrace *rec;
struct ftrace_page *pg;
- unsigned long s = (unsigned long)start;
- unsigned long e = (unsigned long)end;

- if (ftrace_disabled || !start || start == end)
+ if (ftrace_disabled)
return;

mutex_lock(&ftrace_lock);
do_for_each_ftrace_rec(pg, rec) {
- if ((rec->ip >= s) && (rec->ip < e)) {
+ if (within_module_core(rec->ip, mod)) {
/*
* rec->ip is changed in ftrace_free_rec()
* It should not between s and e if record was freed.
@@ -2845,9 +2843,7 @@ static int ftrace_module_notify(struct n
mod->num_ftrace_callsites);
break;
case MODULE_STATE_GOING:
- ftrace_release(mod->ftrace_callsites,
- mod->ftrace_callsites +
- mod->num_ftrace_callsites);
+ ftrace_release_mod(mod);
break;
}