Re: [PATCH v3] mm/page_owner: fix for deferred struct page init

From: William Kucharski
Date: Thu Dec 20 2018 - 16:00:41 EST




> On Dec 20, 2018, at 1:31 PM, Qian Cai <cai@xxxxxx> wrote:
>
> diff --git a/mm/page_ext.c b/mm/page_ext.c
> index ae44f7adbe07..d76fd51e312a 100644
> --- a/mm/page_ext.c
> +++ b/mm/page_ext.c
> @@ -399,9 +399,8 @@ void __init page_ext_init(void)
> * -------------pfn-------------->
> * N0 | N1 | N2 | N0 | N1 | N2|....
> *
> - * Take into account DEFERRED_STRUCT_PAGE_INIT.
> */
> - if (early_pfn_to_nid(pfn) != nid)
> + if (pfn_to_nid(pfn) != nid)
> continue;
> if (init_section_page_ext(pfn, nid))
> goto oom;
> --
> 2.17.2 (Apple Git-113)
>

Is there any danger in the fact that in the CONFIG_NUMA case in mmzone.h (around line 1261), pfn_to_nid() calls page_to_nid(), possibly causing the same issue seen in v2?