Re: [dpdk-stable] [PATCH][v4.9.y] Fixes: 3c226c637b69 ("mm: numa: avoid waiting on freed migrated pages")

[Yongseok Koh <yskoh@mellanox.com>]

> On Sep 4, 2018, at 5:51 PM, Chas Williams <3chas3@gmail.com> wrote:
> 
> From: Chas Williams <chas3@att.com>
> 
> Commit 3c226c637b69 ("mm: numa: avoid waiting on freed migrated pages")
> was an incomplete backport of the upstream commit.  It is necessary to
> always reset page_nid before attempting any early exit.
> ---
> mm/huge_memory.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index 9efe88ef9702..e4c6c3edaf6a 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c

Looks like a kernel patch has been sent to DPDK community. ;-)

Thanks,
Yongseok

> @@ -1259,12 +1259,12 @@ int do_huge_pmd_numa_page(struct fault_env *fe, pmd_t pmd)
> 
> 	/* Migration could have started since the pmd_trans_migrating check */
> 	if (!page_locked) {
> +		page_nid = -1;
> 		if (!get_page_unless_zero(page))
> 			goto out_unlock;
> 		spin_unlock(fe->ptl);
> 		wait_on_page_locked(page);
> 		put_page(page);
> -		page_nid = -1;
> 		goto out;
> 	}
> 
> -- 
> 2.14.4
>