lkml.org 
[lkml]   [2010]   [Sep]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: ftrace/perf_event leak
>> Subject: perf, trace: Fix module leak
>> From: Li Zefan <lizf@cn.fujitsu.com>
>> Date: Wed Sep 01 12:58:43 CEST 2010
>>
>> Commit 1c024eca (perf, trace: Optimize tracepoints by using
>> per-tracepoint-per-cpu hlist to track events) caused a module refcount
>> leak.
>>
>> Tested-by: Avi Kivity <avi@redhat.com>
>> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
>> LKML-Reference: <4C7E1F12.8030304@cn.fujitsu.com>
>> ---
>> kernel/trace/trace_event_perf.c | 3 +++
>> 1 file changed, 3 insertions(+)
>>
>> Index: linux-2.6/kernel/trace/trace_event_perf.c
>> ===================================================================
>> --- linux-2.6.orig/kernel/trace/trace_event_perf.c
>> +++ linux-2.6/kernel/trace/trace_event_perf.c
>> @@ -91,6 +91,8 @@ int perf_trace_init(struct perf_event *p
>> tp_event->class && tp_event->class->reg &&
>> try_module_get(tp_event->mod)) {
>> ret = perf_trace_event_init(tp_event, p_event);
>> + if (ret)
>> + module_put(tp_event->mod);
>> break;
>> }
>> }
>> @@ -147,6 +149,7 @@ void perf_trace_destroy(struct perf_even
>> }
>> }
>> out:
>> + module_put(tp_event->mod);
>> mutex_unlock(&event_mutex);
>> }
>>
>>
>
> Thanks for fixing this.
>
> However, can we split this in two patches to ease the backport?
>
> The lack of a module_put() after perf_trace_init() failure is there for a while
> (the backport needs to start in 2.6.32).

The failure should be a rare case, I don't think this has to be backported?

>
> But the lack of a module_put in the destroy path needs a .35 backport only.
>



\
 
 \ /
  Last update: 2010-09-02 03:19    [W:0.081 / U:0.960 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site