RE: [PATCH 1/1] mm/hugetlb: Set PTE as huge in hugetlb_change_protection

[Tony Lu <zlu@tilera.com>]

>-----Original Message-----
>From: Michal Hocko [mailto:mhocko@suse.cz]
>Sent: Monday, January 21, 2013 6:04 PM
>To: Tony Lu
>Cc: linux-kernel@vger.kernel.org; linux-mm@kvack.org; Andrew Morton; Aneesh
>Kumar K.V; Hillf Danton; KAMEZAWA Hiroyuki; Chris Metcalf
>Subject: Re: [PATCH 1/1] mm/hugetlb: Set PTE as huge in
>hugetlb_change_protection
>
>On Mon 21-01-13 04:13:07, Tony Lu wrote:
>> From da8432aafd231e7cdcda9d15484829def4663cb0 Mon Sep 17 00:00:00 2001
>> From: Zhigang Lu <zlu@tilera.com>
>> Date: Mon, 21 Jan 2013 11:23:26 +0800
>> Subject: [PATCH 1/1] mm/hugetlb: Set PTE as huge in hugetlb_change_protection
>>
>> When setting a huge PTE, besides calling pte_mkhuge(), we also need
>> to call arch_make_huge_pte(), which we indeed do in make_huge_pte(),
>> but we forget to do in hugetlb_change_protection().
>
>I guess you also need it in remove_migration_pte. This calls for a
>helper which would do both pte_mkhuge() and arch_make_huge_pte.
>
>Besides that, tile seem to be the only arch which implements this arch
>hook (introduced by 621b1955 in 3.5) so this should be considered for
>stable.

Thank you. Yes, remove_migration_pte also needs it. Here is the updated patch.