Re: [PATCH v3 3/6] powerpc/fsl_booke/64: implement KASLR for fsl_booke64

From: Christophe Leroy <christophe.leroy@c-s.fr>
To: Jason Yan <yanaijie@huawei.com>,
	mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org,
	diana.craciun@nxp.com, benh@kernel.crashing.org,
	paulus@samba.org, npiggin@gmail.com, keescook@chromium.org,
	kernel-hardening@lists.openwall.com, oss@buserror.net
Cc: linux-kernel@vger.kernel.org, zhaohongjiang@huawei.com
Subject: Re: [PATCH v3 3/6] powerpc/fsl_booke/64: implement KASLR for fsl_booke64
Date: Wed, 26 Feb 2020 06:10:22 +0100	[thread overview]
Message-ID: <ceeced29-c6b9-60c9-41b0-3cf537bbf62c@c-s.fr> (raw)
In-Reply-To: <d3647cce-ece3-d302-f541-b02b1f2b5e9e@huawei.com>

Le 26/02/2020 à 04:33, Jason Yan a écrit :
> 
> 
> 在 2020/2/26 10:40, Jason Yan 写道:
>>
>>
>> 在 2020/2/20 21:48, Christophe Leroy 写道:
>>>
>>>
>>> Le 06/02/2020 à 03:58, Jason Yan a écrit :
> Hi Christophe,
> 
> When using a standard C if/else, all code compiled for PPC32 and PPC64, 
> but this will bring some build error because not all variables both 
> defined for PPC32 and PPC64.
> 
> [yanaijie@138 linux]$ sh ppc64build.sh
>    CALL    scripts/atomic/check-atomics.sh
>    CALL    scripts/checksyscalls.sh
>    CHK     include/generated/compile.h
>    CC      arch/powerpc/mm/nohash/kaslr_booke.o
> arch/powerpc/mm/nohash/kaslr_booke.c: In function 'kaslr_choose_location':
> arch/powerpc/mm/nohash/kaslr_booke.c:341:30: error: 
> 'CONFIG_LOWMEM_CAM_NUM' undeclared (first use in this function); did you 
> mean 'CONFIG_FLATMEM_MANUAL'?
>     ram = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM, true);
>                                ^~~~~~~~~~~~~~~~~~~~~
>                                CONFIG_FLATMEM_MANUAL

This one has to remain inside an #ifdef. That's the only one that has to 
remain.

> arch/powerpc/mm/nohash/kaslr_booke.c:341:30: note: each undeclared 
> identifier is reported only once for each function it appears in
> arch/powerpc/mm/nohash/kaslr_booke.c: In function 'kaslr_early_init':
> arch/powerpc/mm/nohash/kaslr_booke.c:404:3: error: 'is_second_reloc' 

In mmu_decl.h, put the declaration outside the #ifdef CONFIG_PPC32

> undeclared (first use in this function); did you mean '__cond_lock'?
>     is_second_reloc = 1;
>     ^~~~~~~~~~~~~~~
>     __cond_lock
> arch/powerpc/mm/nohash/kaslr_booke.c:411:4: error: implicit declaration 
> of function 'create_kaslr_tlb_entry'; did you mean 'reloc_kernel_entry'? 

Same, put the declaration outside of the #ifdef

> [-Werror=implicit-function-declaration]
>      create_kaslr_tlb_entry(1, tlb_virt, tlb_phys);
>      ^~~~~~~~~~~~~~~~~~~~~~
>      reloc_kernel_entry
> cc1: all warnings being treated as errors
> make[3]: *** [scripts/Makefile.build:268: 
> arch/powerpc/mm/nohash/kaslr_booke.o] Error 1
> make[2]: *** [scripts/Makefile.build:505: arch/powerpc/mm/nohash] Error 2
> make[1]: *** [scripts/Makefile.build:505: arch/powerpc/mm] Error 2
> make: *** [Makefile:1681: arch/powerpc] Error 2

See the patch I sent you. It builds ok for me.

Christophe