[RFC PATCH 2/4] objtool: Enable objtool to run only on files with ftrace enabled

[Christophe Leroy]

Hi Sathvika

Le 24/05/2022 à 12:53, Sathvika Vasireddy a écrit :
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> 
> Hi Christophe,
> 
> On 24/05/22 14:27, Christophe Leroy wrote:
>>
>> Le 23/05/2022 à 19:55, Sathvika Vasireddy a écrit :
>>> This patch makes sure objtool runs only on the object files
>>> that have ftrace enabled, instead of running on all the object
>>> files.
>> Why do that ?
> This was done to address the issue discussed here:
> https://lore.kernel.org/all/b06bb9bc-22d1-acce-fe68-c7c4cb7c15b5@csgroup.eu/ 

Ah ? Ok.

But how does x86 do it at the moment ? Shouldn't we use 
OBJECT_FILES_NON_STANDARD instead ?


> 
> 
>>
>> What about static_calls ? There may be files without ftrace but with
>> static calls.
> Yes, this prevents objtool from running on those files. We can
> restrict this change to FTRACE_MCOUNT_USE_OBJTOOL
>>
>> By the way, it would be nice if we could use it only on C files.
>> I get the following errors for ASM files:
>>
>> arch/powerpc/kernel/entry_32.o: warning: objtool: .text+0x1b4:
>> unannotated intra-function call
> 
> I'm looking into ways to address this.
> 

Nice.

Christophe