On Wed, Jun 14, 2023 at 04:57:37PM +0200, David Hildenbrand wrote: > On 13.06.23 23:53, Peter Xu wrote: > > It's coming, not yet, but soon. Loose the restriction. > > > > Signed-off-by: Peter Xu <peterx@xxxxxxxxxx> > > --- > > mm/hugetlb.c | 7 ------- > > 1 file changed, 7 deletions(-) > > > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > > index f037eaf9d819..31d8f18bc2e4 100644 > > --- a/mm/hugetlb.c > > +++ b/mm/hugetlb.c > > @@ -6467,13 +6467,6 @@ struct page *hugetlb_follow_page_mask(struct vm_area_struct *vma, > > spinlock_t *ptl; > > pte_t *pte, entry; > > - /* > > - * FOLL_PIN is not supported for follow_page(). Ordinary GUP goes via > > - * follow_hugetlb_page(). > > - */ > > - if (WARN_ON_ONCE(flags & FOLL_PIN)) > > - return NULL; > > - > > hugetlb_vma_lock_read(vma); > > pte = hugetlb_walk(vma, haddr, huge_page_size(h)); > > if (!pte) > Did you fix why the warning was placed there in the first place? (IIRC, at > least unsharing support needs to be added, maybe more) Feel free to have a look at patch 2 - it should be done there, hopefully in the right way. And IIUC it could be a bug to not do that before (besides CoR there was also the pgtable permission checks that was missing). More details in patch 2's commit message. Thanks, -- Peter Xu
