Re: [PATCH] powerpc/vdso: Fix build of VDSO32 with pcrel

[Madhavan Srinivasan <maddy@linux.ibm.com>]

On 6/10/25 11:33 AM, Christophe Leroy wrote:
> Hi Maddy,
> 
> ping ?

Yes, its not lost :) . Will add it for the next fixes PR.

Maddy

> 
> Christophe
> 
> Le 12/05/2025 à 20:14, Christophe Leroy a écrit :
>> Building vdso32 on power10 with pcrel leads to following errors:
>>
>>       VDSO32A arch/powerpc/kernel/vdso/gettimeofday-32.o
>>     arch/powerpc/kernel/vdso/gettimeofday.S: Assembler messages:
>>     arch/powerpc/kernel/vdso/gettimeofday.S:40: Error: syntax error; found `@', expected `,'
>>     arch/powerpc/kernel/vdso/gettimeofday.S:71:  Info: macro invoked from here
>>     arch/powerpc/kernel/vdso/gettimeofday.S:40: Error: junk at end of line: `@notoc'
>>     arch/powerpc/kernel/vdso/gettimeofday.S:71:  Info: macro invoked from here
>>      ...
>>     make[2]: *** [arch/powerpc/kernel/vdso/Makefile:85: arch/powerpc/kernel/vdso/gettimeofday-32.o] Error 1
>>     make[1]: *** [arch/powerpc/Makefile:388: vdso_prepare] Error 2
>>
>> Once the above is fixed, the following happens:
>>
>>       VDSO32C arch/powerpc/kernel/vdso/vgettimeofday-32.o
>>     cc1: error: '-mpcrel' requires '-mcmodel=medium'
>>     make[2]: *** [arch/powerpc/kernel/vdso/Makefile:89: arch/powerpc/kernel/vdso/vgettimeofday-32.o] Error 1
>>     make[1]: *** [arch/powerpc/Makefile:388: vdso_prepare] Error 2
>>     make: *** [Makefile:251: __sub-make] Error 2
>>
>> Make sure pcrel version of CFUNC() macro is used only for powerpc64
>> builds and remove -mpcrel for powerpc32 builds.
>>
>> Fixes: 7e3a68be42e1 ("powerpc/64: vmlinux support building with PCREL addresing")
>> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
>> ---
>>   arch/powerpc/include/asm/ppc_asm.h | 2 +-
>>   arch/powerpc/kernel/vdso/Makefile  | 2 +-
>>   2 files changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h
>> index 02897f4b0dbf..b891910fce8a 100644
>> --- a/arch/powerpc/include/asm/ppc_asm.h
>> +++ b/arch/powerpc/include/asm/ppc_asm.h
>> @@ -183,7 +183,7 @@
>>   /*
>>    * Used to name C functions called from asm
>>    */
>> -#ifdef CONFIG_PPC_KERNEL_PCREL
>> +#if defined(__powerpc64__) && defined(CONFIG_PPC_KERNEL_PCREL)
>>   #define CFUNC(name) name@notoc
>>   #else
>>   #define CFUNC(name) name
>> diff --git a/arch/powerpc/kernel/vdso/Makefile b/arch/powerpc/kernel/vdso/Makefile
>> index e8824f933326..8834dfe9d727 100644
>> --- a/arch/powerpc/kernel/vdso/Makefile
>> +++ b/arch/powerpc/kernel/vdso/Makefile
>> @@ -53,7 +53,7 @@ ldflags-$(CONFIG_LD_ORPHAN_WARN) += -Wl,--orphan-handling=$(CONFIG_LD_ORPHAN_WAR
>>   ldflags-y += $(filter-out $(CC_AUTO_VAR_INIT_ZERO_ENABLER) $(CC_FLAGS_FTRACE) -Wa$(comma)%, $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
>>     CC32FLAGS := -m32
>> -CC32FLAGSREMOVE := -mcmodel=medium -mabi=elfv1 -mabi=elfv2 -mcall-aixdesc
>> +CC32FLAGSREMOVE := -mcmodel=medium -mabi=elfv1 -mabi=elfv2 -mcall-aixdesc -mpcrel
>>   ifdef CONFIG_CC_IS_CLANG
>>   # This flag is supported by clang for 64-bit but not 32-bit so it will cause
>>   # an unused command line flag warning for this file.
>