[akpm-mm:mm-new 117/130] ./include/asm-generic/fixmap.h:77:9: error: implicit declaration of function '__set_fixmap'; did you mean 'set_fixmap'?

[akpm-mm:mm-new 117/130] ./include/asm-generic/fixmap.h:77:9: error: implicit declaration of function '__set_fixmap'; did you mean 'set_fixmap'?

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-new
head:   4f7b2cc1ad8719d55a8de9675a0aca65cb17c364
commit: 93580c23bb3da5dd2926d6ae991ef04c2cdacaf2 [117/130] include/asm-generic/fixmap.h: reimplement nasty macros in C
config: powerpc64-allnoconfig-bpf (https://download.01.org/0day-ci/archive/20260427/202604271114.ebmzs1LE-lkp@intel.com/config)
compiler: powerpc64-linux-gnu-gcc (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260427/202604271114.ebmzs1LE-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/r/202604271114.ebmzs1LE-lkp@intel.com/

All error/warnings (new ones prefixed by >>):

   In file included from ./arch/powerpc/include/asm/fixmap.h:91,
                    from mm/early_ioremap.c:18:
   ./include/asm-generic/fixmap.h: In function '__set_fixmap_offset':
>> ./include/asm-generic/fixmap.h:77:9: error: implicit declaration of function '__set_fixmap'; did you mean 'set_fixmap'? [-Wimplicit-function-declaration]
      77 |         __set_fixmap(idx, phys, flags);
         |         ^~~~~~~~~~~~
         |         set_fixmap
   ./arch/powerpc/include/asm/fixmap.h: At top level:
>> ./arch/powerpc/include/asm/fixmap.h:93:20: warning: conflicting types for '__set_fixmap'; have 'void(enum fixed_addresses,  phys_addr_t,  pgprot_t)' {aka 'void(enum fixed_addresses,  long long unsigned int,  pgprot_t)'}
      93 | static inline void __set_fixmap(enum fixed_addresses idx,
         |                    ^~~~~~~~~~~~
>> ./arch/powerpc/include/asm/fixmap.h:93:20: error: static declaration of '__set_fixmap' follows non-static declaration
   ./include/asm-generic/fixmap.h:77:9: note: previous implicit declaration of '__set_fixmap' with type 'void(enum fixed_addresses,  phys_addr_t,  pgprot_t)' {aka 'void(enum fixed_addresses,  long long unsigned int,  pgprot_t)'}
      77 |         __set_fixmap(idx, phys, flags);
         |         ^~~~~~~~~~~~


vim +77 ./include/asm-generic/fixmap.h

d57c33c5daa4ef Mark Salter   2014-01-23  72  
d57c33c5daa4ef Mark Salter   2014-01-23  73  /* Return a pointer with offset calculated */
93580c23bb3da5 Andrew Morton 2026-04-25  74  static inline unsigned long
93580c23bb3da5 Andrew Morton 2026-04-25  75  __set_fixmap_offset(enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)
93580c23bb3da5 Andrew Morton 2026-04-25  76  {
93580c23bb3da5 Andrew Morton 2026-04-25 @77  	__set_fixmap(idx, phys, flags);
93580c23bb3da5 Andrew Morton 2026-04-25  78  	return fix_to_virt(idx) + (phys & (PAGE_SIZE - 1));
93580c23bb3da5 Andrew Morton 2026-04-25  79  }
d57c33c5daa4ef Mark Salter   2014-01-23  80  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [akpm-mm:mm-new 117/130] ./include/asm-generic/fixmap.h:77:9: error: implicit declaration of function '__set_fixmap'; did you mean 'set_fixmap'?

[Andrew Morton]

On Mon, 27 Apr 2026 22:45:39 +0800 kernel test robot <lkp@intel.com> wrote:

> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-new
> head:   4f7b2cc1ad8719d55a8de9675a0aca65cb17c364
> commit: 93580c23bb3da5dd2926d6ae991ef04c2cdacaf2 [117/130] include/asm-generic/fixmap.h: reimplement nasty macros in C
> config: powerpc64-allnoconfig-bpf (https://download.01.org/0day-ci/archive/20260427/202604271114.ebmzs1LE-lkp@intel.com/config)
> compiler: powerpc64-linux-gnu-gcc (Debian 14.2.0-19) 14.2.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260427/202604271114.ebmzs1LE-lkp@intel.com/reproduce)
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/r/202604271114.ebmzs1LE-lkp@intel.com/
> 
> All error/warnings (new ones prefixed by >>):
> 
>    In file included from ./arch/powerpc/include/asm/fixmap.h:91,
>                     from mm/early_ioremap.c:18:
>    ./include/asm-generic/fixmap.h: In function '__set_fixmap_offset':
> >> ./include/asm-generic/fixmap.h:77:9: error: implicit declaration of function '__set_fixmap'; did you mean 'set_fixmap'? [-Wimplicit-function-declaration]
>       77 |         __set_fixmap(idx, phys, flags);
>          |         ^~~~~~~~~~~~
>          |         set_fixmap
>    ./arch/powerpc/include/asm/fixmap.h: At top level:
> >> ./arch/powerpc/include/asm/fixmap.h:93:20: warning: conflicting types for '__set_fixmap'; have 'void(enum fixed_addresses,  phys_addr_t,  pgprot_t)' {aka 'void(enum fixed_addresses,  long long unsigned int,  pgprot_t)'}
>       93 | static inline void __set_fixmap(enum fixed_addresses idx,
>          |                    ^~~~~~~~~~~~

Sigh, thanks, of course one architecture had to go and be weird.

hacky fix:

--- a/arch/powerpc/include/asm/fixmap.h~include-asm-generic-fixmaph-reimplement-nasty-macros-in-c-fix-fix
+++ a/arch/powerpc/include/asm/fixmap.h
@@ -88,6 +88,9 @@ enum fixed_addresses {
 #define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_NCG
 #define FIXMAP_PAGE_IO	PAGE_KERNEL_NCG
 
+static inline void __set_fixmap(enum fixed_addresses idx,
+				phys_addr_t phys, pgprot_t flags);
+
 #include <asm-generic/fixmap.h>
 
 static inline void __set_fixmap(enum fixed_addresses idx,
_