[PATCH] mm/hugetlb: Fix build failure with HUGETLB_PAGE but not HUGEBTLBFS

[Andrew Morton]

On Tue, 17 Mar 2020 08:04:14 +0000 (UTC) Christophe Leroy <christophe.leroy at c-s.fr> wrote:

> When CONFIG_HUGETLB_PAGE is set but not CONFIG_HUGETLBFS, the
> following build failure is encoutered:
> 
> In file included from arch/powerpc/mm/fault.c:33:0:
> ./include/linux/hugetlb.h: In function 'hstate_inode':
> ./include/linux/hugetlb.h:477:9: error: implicit declaration of function 'HUGETLBFS_SB' [-Werror=implicit-function-declaration]
>   return HUGETLBFS_SB(i->i_sb)->hstate;
>          ^
> ./include/linux/hugetlb.h:477:30: error: invalid type argument of '->' (have 'int')
>   return HUGETLBFS_SB(i->i_sb)->hstate;
>                               ^
> 
> Gate hstate_inode() with CONFIG_HUGETLBFS instead of CONFIG_HUGETLB_PAGE.
> 
> Reported-by: kbuild test robot <lkp at intel.com>
> Link: https://patchwork.ozlabs.org/patch/1255548/#2386036
> Fixes: a137e1cc6d6e ("hugetlbfs: per mount huge page sizes")

A 12 year old build error?  If accurate, that has to be a world record.

> Cc: stable at vger.kernel.org

I think I'll remove this.  Obviously nobody is suffering from this problem!