[main-line]Build warnings on PowerPC system

[Christophe Leroy]

Le 27/03/2025 à 17:24, Venkat Rao Bagalkote a écrit :
> 
> On 27/03/25 8:36 pm, Madhavan Srinivasan wrote:
>>
>> On 3/27/25 7:31 PM, Venkat Rao Bagalkote wrote:
>>> On 27/03/25 7:22 pm, Madhavan Srinivasan wrote:
>>>> On 3/27/25 12:33 AM, Venkat Rao Bagalkote wrote:
>>>>> Greetings!!!
>>>>>
>>>>> I see below build warnings while compiling mainline kernel on IBM 
>>>>> Power9 system.
>>>>>
>>>>> Repo Link: https://eur01.safelinks.protection.outlook.com/? 
>>>>> url=https%3A%2F%2Fgit.kernel.org%2Fpub%2Fscm%2Flinux%2Fkernel%2Fgit%2Ftorvalds%2Flinux.git%2F&data=05%7C02%7Cchristophe.leroy2%40cs-soprasteria.com%7Cd6121f3814a7497bc5e608dd6d4be6c8%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C638786894952762400%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=3el3Uw9JR2vxDzjOIvF%2BVnienBrwtOsA%2Ftg0kGBqziE%3D&reserved=0
>>>>>
>>>>> Head Commit: f6e0150b2003fb2b9265028a618aa1732b3edc8f
>>>>>
>>>>> Attached is the .config.
>>>>>
>>>>> Machine: IBM Power9
>>>>>
>>>>> gcc version 11.5.0
>>>> What is the ld version in your system.
>>> Please find the ld version below.
>>>
>>> GNU ld version 2.35.2-59.el9
>>
>> ah ok that explains. Kindly can you try with this patch and let us 
>> know whether
>> this fixes the warning in your setup
>>
>>
>> diff --git a/arch/powerpc/boot/wrapper b/arch/powerpc/boot/wrapper
>> index 1db60fe13802..09ceb5a42d81 100755
>> --- a/arch/powerpc/boot/wrapper
>> +++ b/arch/powerpc/boot/wrapper
>> @@ -235,7 +235,7 @@ fi
>>   # suppress some warnings in recent ld versions
>>   nowarn="-z noexecstack"
>>   if ! ld_is_lld; then
>> -       if [ "$LD_VERSION" -ge "$(echo 2.39 | ld_version)" ]; then
>> +       if [ "$LD_VERSION" -ge "$(echo 2.35 | ld_version)" ]; then
>>                  nowarn="$nowarn --no-warn-rwx-segments"
>>          fi
>>   fi
> Above change fixes the issue. No warnings observed. Thank you!!

Take care, this must be a special version of binutils.

With regular 2.36.1 I get following error:

$ /opt/gcc/gcc-8.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version
GNU ld (GNU Binutils) 2.36.1
Copyright (C) 2021 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License version 3 or (at your option) a later 
version.
This program has absolutely no warranty.

$ /opt/gcc/gcc-8.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld 
--no-warn-rwx-segments test.o
/opt/gcc/gcc-8.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld: 
unrecognized option '--no-warn-rwx-segments'
/opt/gcc/gcc-8.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld: use 
the --help option for usage information