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From: Zhaolei <zhaolei@cn.fujitsu.com>
To: "Steven Rostedt ;" <rostedt@goodmis.org>, Ingo Molnar <mingo@elte.hu>
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH] ftrace: Avoid double-free of dyn_ftrace
Date: Fri, 13 Mar 2009 17:14:01 +0800	[thread overview]
Message-ID: <49BA23D9.1050900@cn.fujitsu.com> (raw)

If dyn_ftrace is free before ftrace_release(),
ftrace_release() will free it again and make ftrace_free_records wrong.

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
---
 kernel/trace/ftrace.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index d33d306..26c45aa 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -356,7 +356,8 @@ void ftrace_release(void *start, unsigned long size)
 
 	mutex_lock(&ftrace_lock);
 	do_for_each_ftrace_rec(pg, rec) {
-		if ((rec->ip >= s) && (rec->ip < e))
+		if ((rec->ip >= s) && (rec->ip < e) &&
+		    !(rec->flags & FTRACE_FL_FREE))
 			ftrace_free_rec(rec);
 	} while_for_each_ftrace_rec();
 	mutex_unlock(&ftrace_lock);
-- 
1.5.5.3



             reply	other threads:[~2009-03-13  9:15 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-03-13  9:14 Zhaolei [this message]
2009-03-13  9:25 ` [PATCH] ftrace: Avoid double-free of dyn_ftrace Ingo Molnar
2009-03-13  9:30   ` Zhaolei
2009-03-24 15:54     ` Steven Rostedt
2009-03-25  2:25       ` Zhaolei
2009-03-25  2:35         ` Steven Rostedt
2009-03-13  9:33 ` [tip:tracing/ftrace] ftrace: avoid " Zhaolei

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