tree: git://github.com/davidhildenbrand/linux reuse_swap_page head: 09189ec334fe531619f81fa068bea808d80ad2cc commit: a872bc92d703c5048a66505acae4480615a0d634 [6/10] mm/khugepaged: remove reuse_swap_page() usage config: s390-buildonly-randconfig-r004-20220124 (https://download.01.org/0day-ci/archive/20220125/202201252354.dFsFKZi4-lk...) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 997e128e2a78f5a5434fc75997441ae1ee76f8a4) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install s390 cross compiling tool for clang build # apt-get install binutils-s390x-linux-gnu # https://github.com/davidhildenbrand/linux/commit/a872bc92d703c5048a66505a... git remote add davidhildenbrand git://github.com/davidhildenbrand/linux git fetch --no-tags davidhildenbrand reuse_swap_page git checkout a872bc92d703c5048a66505acae4480615a0d634 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): (PageKSM(page) || !try_to_free_swap(page))) { ^ mm/khugepaged.c:686:8: note: did you mean 'PageKsm'? include/linux/page-flags.h:609:29: note: 'PageKsm' declared here static __always_inline bool PageKsm(struct page *page) ^ 1 error generated. vim +/PageKSM +686 mm/khugepaged.c 600 601 static int __collapse_huge_page_isolate(struct vm_area_struct *vma, 602 unsigned long address, 603 pte_t *pte, 604 struct list_head *compound_pagelist) 605 { 606 struct page *page = NULL; 607 pte_t *_pte; 608 int none_or_zero = 0, shared = 0, result = 0, referenced = 0; 609 bool writable = false; 610 611 for (_pte = pte; _pte < pte+HPAGE_PMD_NR; 612 _pte++, address += PAGE_SIZE) { 613 pte_t pteval = *_pte; 614 if (pte_none(pteval) || (pte_present(pteval) && 615 is_zero_pfn(pte_pfn(pteval)))) { 616 if (!userfaultfd_armed(vma) && 617 ++none_or_zero <= khugepaged_max_ptes_none) { 618 continue; 619 } else { 620 result = SCAN_EXCEED_NONE_PTE; 621 count_vm_event(THP_SCAN_EXCEED_NONE_PTE); 622 goto out; 623 } 624 } 625 if (!pte_present(pteval)) { 626 result = SCAN_PTE_NON_PRESENT; 627 goto out; 628 } 629 page = vm_normal_page(vma, address, pteval); 630 if (unlikely(!page)) { 631 result = SCAN_PAGE_NULL; 632 goto out; 633 } 634 635 VM_BUG_ON_PAGE(!PageAnon(page), page); 636 637 if (page_mapcount(page) > 1 && 638 ++shared > khugepaged_max_ptes_shared) { 639 result = SCAN_EXCEED_SHARED_PTE; 640 count_vm_event(THP_SCAN_EXCEED_SHARED_PTE); 641 goto out; 642 } 643 644 if (PageCompound(page)) { 645 struct page *p; 646 page = compound_head(page); 647 648 /* 649 * Check if we have dealt with the compound page 650 * already 651 */ 652 list_for_each_entry(p, compound_pagelist, lru) { 653 if (page == p) 654 goto next; 655 } 656 } 657 658 /* 659 * We can do it before isolate_lru_page because the 660 * page can't be freed from under us. NOTE: PG_lock 661 * is needed to serialize against split_huge_page 662 * when invoked from the VM. 663 */ 664 if (!trylock_page(page)) { 665 result = SCAN_PAGE_LOCK; 666 goto out; 667 } 668 669 /* 670 * Check if the page has any GUP (or other external) pins. 671 * 672 * The page table that maps the page has been already unlinked 673 * from the page table tree and this process cannot get 674 * an additional pin on the page. 675 * 676 * New pins can come later if the page is shared across fork, 677 * but not from this process. The other process cannot write to 678 * the page, only trigger CoW. 679 */ 680 if (!is_refcount_suitable(page)) { 681 unlock_page(page); 682 result = SCAN_PAGE_COUNT; 683 goto out; 684 } 685 if (!pte_write(pteval) && PageSwapCache(page) && 687 /* 688 * Page cannot be removed from the swapache. 689 * It cannot be collapsed into a THP. 690 */ 691 unlock_page(page); 692 result = SCAN_SWAP_CACHE_PAGE; 693 goto out; 694 } 695 696 /* 697 * Isolate the page to avoid collapsing an hugepage 698 * currently in use by the VM. 699 */ 700 if (isolate_lru_page(page)) { 701 unlock_page(page); 702 result = SCAN_DEL_PAGE_LRU; 703 goto out; 704 } 705 706 /* 707 * We're holding the page lock and removed the page from the 708 * LRU. Once done copying, we'll unlock and readd to the 709 * LRU via release_pte_page(). The page cannot get added 710 * to the swapcache in the meantime. 711 */ 712 mod_node_page_state(page_pgdat(page), 713 NR_ISOLATED_ANON + page_is_file_lru(page), 714 compound_nr(page)); 715 VM_BUG_ON_PAGE(!PageLocked(page), page); 716 VM_BUG_ON_PAGE(PageLRU(page), page); 717 718 if (PageCompound(page)) 719 list_add_tail(&page->lru, compound_pagelist); 720 next: 721 /* There should be enough young pte to collapse the page */ 722 if (pte_young(pteval) || 723 page_is_young(page) || PageReferenced(page) || 724 mmu_notifier_test_young(vma->vm_mm, address)) 725 referenced++; 726 727 if (pte_write(pteval)) 728 writable = true; 729 } 730 731 if (unlikely(!writable)) { 732 result = SCAN_PAGE_RO; 733 } else if (unlikely(!referenced)) { 734 result = SCAN_LACK_REFERENCED_PAGE; 735 } else { 736 result = SCAN_SUCCEED; 737 trace_mm_collapse_huge_page_isolate(page, none_or_zero, 738 referenced, writable, result); 739 return 1; 740 } 741 out: 742 release_pte_pages(pte, _pte, compound_pagelist); 743 trace_mm_collapse_huge_page_isolate(page, none_or_zero, 744 referenced, writable, result); 745 return 0; 746 } 747 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org