Re: [PATCH 1/2] powerpc: drop dependency on <asm/machdep.h> in archrandom.h

From: Michael Ellerman <mpe@ellerman.id.au>
To: Yury Norov <yury.norov@gmail.com>,
	linux-kernel@vger.kernel.org,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Rasmus Villemoes <linux@rasmusvillemoes.dk>,
	linuxppc-dev@lists.ozlabs.org,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Paul Mackerras <paulus@samba.org>,
	Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Yury Norov <yury.norov@gmail.com>
Subject: Re: [PATCH 1/2] powerpc: drop dependency on <asm/machdep.h> in archrandom.h
Date: Mon, 25 Jul 2022 22:22:13 +1000	[thread overview]
Message-ID: <87wnc1bcwa.fsf@mpe.ellerman.id.au> (raw)
In-Reply-To: <8735epd204.fsf@mpe.ellerman.id.au>

Michael Ellerman <mpe@ellerman.id.au> writes:
> Yury Norov <yury.norov@gmail.com> writes:
>> archrandom.h includes <asm/machdep.h> to refer ppc_md. This causes
>> circular header dependency, if generic nodemask.h  includes random.h:
>>
>> In file included from include/linux/cred.h:16,
>>                  from include/linux/seq_file.h:13,
>>                  from arch/powerpc/include/asm/machdep.h:6,
>>                  from arch/powerpc/include/asm/archrandom.h:5,
>>                  from include/linux/random.h:109,
>>                  from include/linux/nodemask.h:97,
>>                  from include/linux/list_lru.h:12,
>>                  from include/linux/fs.h:13,
>>                  from include/linux/compat.h:17,
>>                  from arch/powerpc/kernel/asm-offsets.c:12:
>> include/linux/sched.h:1203:9: error: unknown type name 'nodemask_t'
>>  1203 |         nodemask_t                      mems_allowed;
>>       |         ^~~~~~~~~~
>>
>> Fix it by removing <asm/machdep.h> dependency from archrandom.h
>>
>> Signed-off-by: Yury Norov <yury.norov@gmail.com>
>> ---
>>  arch/powerpc/include/asm/archrandom.h |  9 +--------
>>  arch/powerpc/kernel/setup-common.c    | 11 +++++++++++
>>  2 files changed, 12 insertions(+), 8 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/archrandom.h b/arch/powerpc/include/asm/archrandom.h
>> index 9a53e29680f4..21def59ef1a6 100644
>> --- a/arch/powerpc/include/asm/archrandom.h
>> +++ b/arch/powerpc/include/asm/archrandom.h
>> @@ -4,7 +4,7 @@
>>  
>>  #ifdef CONFIG_ARCH_RANDOM
>>  
>> -#include <asm/machdep.h>
>> +bool __must_check arch_get_random_seed_long(unsigned long *v);
>>  
>>  static inline bool __must_check arch_get_random_long(unsigned long *v)
>>  {
>> @@ -16,13 +16,6 @@ static inline bool __must_check arch_get_random_int(unsigned int *v)
>>  	return false;
>>  }
>>  
>> -static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
>> -{
>> -	if (ppc_md.get_random_seed)
>> -		return ppc_md.get_random_seed(v);
>> -
>> -	return false;
>> -}
>
> I'd rather we didn't have to force this out of line.
>
> I think I see a different way to fix it, I'll just do some more build
> tests.

Of course my idea didn't work :}

So I'll just ack your patch for now, and maybe I can get the headers
cleaned up in future to allow it to be out-of-line again.

cheers