linux-kernel - Re: [RFC PATCH v2 5/7] objtool: Enable objtool to run only on files with ftrace enabled

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <5cb959a2-7e88-5aff-2f8e-be8fdecd002c@csgroup.eu>
Date:   Tue, 24 May 2022 18:59:50 +0000
From:   Christophe Leroy <christophe.leroy@...roup.eu>
To:     Peter Zijlstra <peterz@...radead.org>
CC:     Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        Michael Ellerman <mpe@...erman.id.au>,
        "aik@...abs.ru" <aik@...abs.ru>,
        "sv@...ux.ibm.com" <sv@...ux.ibm.com>,
        "rostedt@...dmis.org" <rostedt@...dmis.org>,
        "jpoimboe@...hat.com" <jpoimboe@...hat.com>,
        "naveen.n.rao@...ux.vnet.ibm.com" <naveen.n.rao@...ux.vnet.ibm.com>,
        "mbenes@...e.cz" <mbenes@...e.cz>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linuxppc-dev@...ts.ozlabs.org" <linuxppc-dev@...ts.ozlabs.org>
Subject: Re: [RFC PATCH v2 5/7] objtool: Enable objtool to run only on files
 with ftrace enabled



Le 24/05/2022 à 20:02, Peter Zijlstra a écrit :
> On Tue, May 24, 2022 at 08:01:39PM +0200, Peter Zijlstra wrote:
>> On Tue, May 24, 2022 at 03:17:45PM +0200, Christophe Leroy wrote:
>>> From: Sathvika Vasireddy <sv@...ux.ibm.com>
>>>
>>> This patch makes sure objtool runs only on the object files
>>> that have ftrace enabled, instead of running on all the object
>>> files.
>>>
>>> Signed-off-by: Naveen N. Rao <naveen.n.rao@...ux.vnet.ibm.com>
>>> Signed-off-by: Sathvika Vasireddy <sv@...ux.ibm.com>
>>> Signed-off-by: Christophe Leroy <christophe.leroy@...roup.eu>
>>> ---
>>>   scripts/Makefile.build | 4 ++--
>>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/scripts/Makefile.build b/scripts/Makefile.build
>>> index 2e0c3f9c1459..06ceffd92921 100644
>>> --- a/scripts/Makefile.build
>>> +++ b/scripts/Makefile.build
>>> @@ -258,8 +258,8 @@ else
>>>   # 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file
>>>   # 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file
>>>   
>>> -$(obj)/%.o: objtool-enabled = $(if $(filter-out y%, \
>>> -	$(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n),y)
>>> +$(obj)/%.o: objtool-enabled = $(and $(if $(filter-out y%, $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n),y),        \
>>> +        $(if $(findstring $(strip $(CC_FLAGS_FTRACE)),$(_c_flags)),y),y)
>>
>> I think this breaks x86, quite a bit of files have ftrace disabled but
>> very much must run objtool anyway.
> 
> Also; since the Changelog gives 0 clue as to what problem it's trying to
> solve, I can't suggest anything.

I asked Sathvika on the previous series, see 
https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20220523175548.922671-3-sv@linux.ibm.com/

He says it is to solve the problem I reported at 
https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20220318105140.43914-4-sv@linux.ibm.com/#2861128

Christophe