On Thu, Dec 5, 2024 at 11:04 PM Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> wrote:
>
> Commit ed48e87c7df3 ("thp: add thp_get_unmapped_area_vmflags()")
> changes thp_get_unmapped_area() to thp_get_unmapped_area_vmflags()
> in __get_unmapped_area(), which won't setup get_area for anonymous
> mappings, but it leads to always try THP align when file ops without
> '.get_unmapped_area' callback too as the get_area is NULL.
>
> Since commit efa7df3e3bb5 ("mm: align larger anonymous mappings on
> THP boundaries") only want to enable THP align for anonymous, adding
> !file check to fix it.
Good catch. Reviewed-by: Yang Shi <shy828301@xxxxxxxxx>
>
> Fixes: ed48e87c7df3 ("thp: add thp_get_unmapped_area_vmflags()")
> Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
> ---
> mm/mmap.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/mmap.c b/mm/mmap.c
> index 1c6bdffa13dd..b373486bd1c6 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -782,7 +782,7 @@ __get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
>
> if (get_area) {
> addr = get_area(file, addr, len, pgoff, flags);
> - } else if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)
> + } else if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && !file
> && !addr /* no hint */
> && IS_ALIGNED(len, PMD_SIZE)) {
> /* Ensures that larger anonymous mappings are THP aligned. */
> --
> 2.27.0
>
