On Tue 22-01-13 02:37:15, Tony Lu wrote: > >-----Original Message----- > >From: Michal Hocko [mailto:[email protected]] > >Sent: Monday, January 21, 2013 6:04 PM > >To: Tony Lu > >Cc: [email protected]; [email protected]; 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 <[email protected]> > >> 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. > > From 44045d672aa72eb2e76be89f95ab720952b4b09c Mon Sep 17 00:00:00 2001 > From: Zhigang Lu <[email protected]> > Date: Tue, 22 Jan 2013 09:58:58 +0800 > Subject: [PATCH 1/1] mm/hugetlb: Set PTE as huge in hugetlb_change_protection > and remove_migration_pte > > 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() and > remove_migration_pte(). > > Signed-off-by: Zhigang Lu <[email protected]> > Signed-off-by: Chris Metcalf <[email protected]>
Reviewed-by: Michal Hocko <[email protected]> > --- > mm/hugetlb.c | 1 + > mm/migrate.c | 4 +++- > 2 files changed, 4 insertions(+), 1 deletion(-) > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index 4f3ea0b..546db81 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -3033,6 +3033,7 @@ unsigned long hugetlb_change_protection(struct > vm_area_struct *vma, > if (!huge_pte_none(huge_ptep_get(ptep))) { > pte = huge_ptep_get_and_clear(mm, address, ptep); > pte = pte_mkhuge(pte_modify(pte, newprot)); > + pte = arch_make_huge_pte(pte, vma, NULL, 0); > set_huge_pte_at(mm, address, ptep, pte); > pages++; > } > diff --git a/mm/migrate.c b/mm/migrate.c > index c387786..2fd8b4a 100644 > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -160,8 +160,10 @@ static int remove_migration_pte(struct page *new, struct > vm_area_struct *vma, > if (is_write_migration_entry(entry)) > pte = pte_mkwrite(pte); > #ifdef CONFIG_HUGETLB_PAGE > - if (PageHuge(new)) > + if (PageHuge(new)) { > pte = pte_mkhuge(pte); > + pte = arch_make_huge_pte(pte, vma, new, 0); > + } > #endif > flush_cache_page(vma, addr, pte_pfn(pte)); > set_pte_at(mm, addr, ptep, pte); > -- > 1.7.10.3 -- Michal Hocko SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
