Re: [PATCH 5.7 0/6] 5.7.14-rc1 review

From: Guenter Roeck
Date: Wed Aug 05 2020 - 15:13:44 EST


On 8/5/20 10:39 AM, Naresh Kamboju wrote:
> On Wed, 5 Aug 2020 at 21:22, Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>>
>> This is the start of the stable review cycle for the 5.7.14 release.
>> There are 6 patches in this series, all will be posted as a response
>> to this one. If anyone has any issues with these being applied, please
>> let me know.
>>
>> Responses should be made by Fri, 07 Aug 2020 15:34:53 +0000.
>> Anything received after that time might be too late.
>>
>> The whole patch series can be found in one patch at:
>> https://www.kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.7.14-rc1.gz
>> or in the git tree and branch at:
>> git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-5.7.y
>> and the diffstat can be found below.
>>
>> thanks,
>>
>> greg k-h
>>
>> -------------
>> Pseudo-Shortlog of commits:
>>
>> Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
>> Linux 5.7.14-rc1
>>
>> Marc Zyngier <maz@xxxxxxxxxx>
>> arm64: Workaround circular dependency in pointer_auth.h
>>
>> Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
>> random32: move the pseudo-random 32-bit definitions to prandom.h
>>
>> Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
>> random32: remove net_rand_state from the latent entropy gcc plugin
>>
>> Willy Tarreau <w@xxxxxx>
>> random: fix circular include dependency on arm64 after addition of percpu.h
>>
>> Grygorii Strashko <grygorii.strashko@xxxxxx>
>> ARM: percpu.h: fix build error
>>
>> Willy Tarreau <w@xxxxxx>
>> random32: update the net random state on interrupt and activity
>>
>
> [ sorry if it is not interesting ! ]
>
> While building with old gcc-7.3.0 the build breaks for arm64
> whereas build PASS on gcc-8, gcc-9 and gcc-10.
>
> with gcc 7.3.0 build breaks log,
>
Same with older versions of gcc. I don't see the problem with the
mainline kernel.

I think this is caused by more recursive includes.
arch/arm64/include/asm/archrandom.h includes include/linux/random.h
which includes arch/arm64/include/asm/archrandom.h to get the definition
of arch_get_random_seed_long_early (which it won't get because of
the recursion).

What I don't really understand is how this works with new versions
of gcc.

Guenter

> In file included from arch/arm64/include/asm/archrandom.h:9:0,
> from arch/arm64/kernel/kaslr.c:14:
> include/linux/random.h: In function 'arch_get_random_seed_long_early':
> include/linux/random.h:149:9: error: implicit declaration of function
> 'arch_get_random_seed_long'; did you mean
> 'arch_get_random_seed_long_early'?
> [-Werror=implicit-function-declaration]
> return arch_get_random_seed_long(v);
> ^~~~~~~~~~~~~~~~~~~~~~~~~
> arch_get_random_seed_long_early
> include/linux/random.h: In function 'arch_get_random_long_early':
> include/linux/random.h:157:9: error: implicit declaration of function
> 'arch_get_random_long'; did you mean 'get_random_long'?
> [-Werror=implicit-function-declaration]
> return arch_get_random_long(v);
> ^~~~~~~~~~~~~~~~~~~~
> get_random_long
> In file included from arch/arm64/kernel/kaslr.c:14:0:
> arch/arm64/include/asm/archrandom.h: At top level:
> arch/arm64/include/asm/archrandom.h:30:33: error: conflicting types
> for 'arch_get_random_long'
> static inline bool __must_check arch_get_random_long(unsigned long *v)
> ^~~~~~~~~~~~~~~~~~~~
> In file included from arch/arm64/include/asm/archrandom.h:9:0,
> from arch/arm64/kernel/kaslr.c:14:
> include/linux/random.h:157:9: note: previous implicit declaration of
> 'arch_get_random_long' was here
> return arch_get_random_long(v);
> ^~~~~~~~~~~~~~~~~~~~
> In file included from arch/arm64/kernel/kaslr.c:14:0:
> arch/arm64/include/asm/archrandom.h:40:33: error: conflicting types
> for 'arch_get_random_seed_long'
> static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
> ^~~~~~~~~~~~~~~~~~~~~~~~~
> In file included from arch/arm64/include/asm/archrandom.h:9:0,
> from arch/arm64/kernel/kaslr.c:14:
> include/linux/random.h:149:9: note: previous implicit declaration of
> 'arch_get_random_seed_long' was here
> return arch_get_random_seed_long(v);
> ^~~~~~~~~~~~~~~~~~~~~~~~~
> In file included from arch/arm64/kernel/kaslr.c:14:0:
> arch/arm64/include/asm/archrandom.h:72:1: error: redefinition of
> 'arch_get_random_seed_long_early'
> arch_get_random_seed_long_early(unsigned long *v)
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> In file included from arch/arm64/include/asm/archrandom.h:9:0,
> from arch/arm64/kernel/kaslr.c:14:
> include/linux/random.h:146:27: note: previous definition of
> 'arch_get_random_seed_long_early' was here
> static inline bool __init arch_get_random_seed_long_early(unsigned long *v)
>
>