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David Alan Gilbert" , "Matthew Wilcox (Oracle)" , Vlastimil Babka , Baolin Wang , Miaohe Lin , Yang Shi , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: qrozrqaxzc3hxdmm7ointcu6j36dnymn X-Rspam-User: X-Rspamd-Queue-Id: 0081612000A X-Rspamd-Server: rspam06 X-HE-Tag: 1673546779-371299 X-HE-Meta: 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 +JcMPYxT qYBw5x/9MuWCvU2VnPT3/6e2SYxiaEqKvKurzvWCQ1FloN6JlL7wOhcNTyQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Jan 12, 2023 at 1:02 PM Peter Xu wrote: > > 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. :) Thanks Peter!! And the `vaddr + pages_per_hpte < vma->vm_end` should be `vaddr + hugetlb_pte_size(&hpte) < vma->vm_end` too.