Re: [PATCH] perf tools: Fix perf_env__find_bpf_prog_info rb tree lookup

From: Song Liu
Date: Tue Apr 16 2019 - 16:25:30 EST




> On Apr 16, 2019, at 7:37 AM, Arnaldo Carvalho de Melo <arnaldo.melo@xxxxxxxxx> wrote:
>
> Em Tue, Apr 16, 2019 at 11:35:54AM -0300, Arnaldo Carvalho de Melo escreveu:
>> Em Tue, Apr 16, 2019 at 04:34:52PM +0200, Jiri Olsa escreveu:
>>> On Tue, Apr 16, 2019 at 11:20:28AM -0300, Arnaldo Carvalho de Melo wrote:
>>>> Em Tue, Apr 16, 2019 at 03:41:51PM +0200, Jiri Olsa escreveu:
>>>>> We currently don't return NULL in case we don't find
>>>>> the bpf_prog_info_node, fixing that.
>>>>
>>>> Can you please try to figure out what was the changeset that introduced
>>>> this problem so that we can have a Fixes: tag that helps me determine if
>>>> this should go to perf/urgent (likely) or (perf/core) and to help the
>>>> stable guys as well?
>>>
>>> sry, I keep forgetting this..
>>>
>>> Fixes: e4378f0cb90b ("perf bpf: Save bpf_prog_info in a rbtree in perf_env")
>>
>> I had just added:
>>
>> Fixes: e4378f0cb90b ("perf bpf: Save bpf_prog_info in a rbtree in perf_env")
>>
>> matches, good :-)
>>
>> At firts I thought hey the look checks for NULL, then, hey, different
>> variable... good catch!
>
> Ah, I also changed the summary from:
>
> "perf tools: Fix perf_env__find_bpf_prog_info rb tree"
>
> to:
>
> perf bpf: Return NULL when RB tree lookup fails in perf_env__find_bpf_prog_info()
>
> Thanks,
>
> - Arnaldo

Thanks Jiri and Arnaldo!

I think we will need similar fix for perf_env__find_btf().

Song