Re: [PATCH v3 2/2] powerpc/64: add stack protector support

From: Michael Ellerman
Date: Wed Sep 26 2018 - 07:51:05 EST


Christophe LEROY <christophe.leroy@xxxxxx> writes:
> Le 26/09/2018 Ã 11:28, Segher Boessenkool a ÃcritÂ:
>> On Wed, Sep 26, 2018 at 09:58:30AM +0200, Christophe LEROY wrote:
>>> Segher, any idea about this problem ?
>>
>>>>> arch/powerpc/platforms/powermac/bootx_init.o: In function `bootx_printf':
>>>>> /var/lib/jenkins-slave/workspace/snowpatch/snowpatch-linux-
>>>>> sparse/linux/arch/powerpc/platforms/powermac/bootx_init.c:88:
>>>>> undefined reference to `__stack_chk_fail_local'
>>
>> Are you building as PIC? Are you linking libssp_nonshared.a? Why not?
>
> Spotted, thanks.
>
> arch/powerpc/platforms/powermac/Makefile contains:
>
> CFLAGS_bootx_init.o += -fPIC
...
>
> Or maybe stack protection on bootx_init doesn't make much sense and we
> could just do the following ?
>
> CFLAGS_bootx_init.o += -fPIC $(call cc-option, -fno-stack-protector)

That would be fine by me.

cheers