Re: [akpm-mm:mm-new 400/411] include/linux/compiler_types.h:572:38: error: call to '__compiletime_assert_486' declared with attribute error: BUILD_BUG failed

[Balbir Singh <balbirs@nvidia.com>]

On 9/11/25 09:47, kernel test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-new
> head:   3a0afa6640282ff559b6f4ff432cffc3ecc2bc77
> commit: 5e59d4de7ff923ce84158f3357c4e964d2ec46af [400/411] mm/migrate_device: implement THP migration of zone device pages
> config: powerpc64-randconfig-003-20250911 (https://download.01.org/0day-ci/archive/20250911/202509110742.wWjLDz1Q-lkp@intel.com/config)
> compiler: powerpc64-linux-gcc (GCC) 8.5.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250911/202509110742.wWjLDz1Q-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/oe-kbuild-all/202509110742.wWjLDz1Q-lkp@intel.com/
> 
> All errors (new ones prefixed by >>):
> 
>    In file included from <command-line>:
>    mm/migrate_device.c: In function '__migrate_device_pages':
>>> include/linux/compiler_types.h:572:38: error: call to '__compiletime_assert_486' declared with attribute error: BUILD_BUG failed
>      _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
>                                          ^
>    include/linux/compiler_types.h:553:4: note: in definition of macro '__compiletime_assert'
>        prefix ## suffix();    \
>        ^~~~~~
>    include/linux/compiler_types.h:572:2: note: in expansion of macro '_compiletime_assert'
>      _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
>      ^~~~~~~~~~~~~~~~~~~
>    include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert'
>     #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
>                                         ^~~~~~~~~~~~~~~~~~
>    include/linux/build_bug.h:59:21: note: in expansion of macro 'BUILD_BUG_ON_MSG'
>     #define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed")
>                         ^~~~~~~~~~~~~~~~
>    include/linux/huge_mm.h:113:28: note: in expansion of macro 'BUILD_BUG'
>     #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
>                                ^~~~~~~~~
>    include/linux/huge_mm.h:117:26: note: in expansion of macro 'HPAGE_PMD_SHIFT'
>     #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
>                              ^~~~~~~~~~~~~~~
>    include/linux/huge_mm.h:118:26: note: in expansion of macro 'HPAGE_PMD_ORDER'
>     #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER)
>                              ^~~~~~~~~~~~~~~
>    mm/migrate_device.c:1101:10: note: in expansion of macro 'HPAGE_PMD_NR'
>         nr = HPAGE_PMD_NR;
>              ^~~~~~~~~~~~

Thanks for the report, I'll fix the use of HPAGE_PMD_NR by protecting it with the right
conditional or using folio_nr_pages()

Balbir