On Thu, Jan 05, 2023 at 10:18:17AM +0000, James Houghton wrote:
> @@ -6731,22 +6746,22 @@ long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
> * and skip the same_page loop below.
> */
> if (!pages && !vmas && !pfn_offset &&
> - (vaddr + huge_page_size(h) < vma->vm_end) &&
> - (remainder >= pages_per_huge_page(h))) {
> - vaddr += huge_page_size(h);
> - remainder -= pages_per_huge_page(h);
> - i += pages_per_huge_page(h);
> + (vaddr + pages_per_hpte < vma->vm_end) &&
> + (remainder >= pages_per_hpte)) {
> + vaddr += pages_per_hpte;
This silently breaks hugetlb GUP.. should be
vaddr += hugetlb_pte_size(&hpte);
It caused misterious MISSING events when I'm playing with this tree, and
I'm surprised it rooted here. So far the most time consuming one. :)
> + remainder -= pages_per_hpte;
> + i += pages_per_hpte;
> spin_unlock(ptl);
> hugetlb_vma_unlock_read(vma);
> continue;
> }
--
Peter Xu
